pup joint or upper nipple extensiom made in china

Pipe system involves various components, including pup joint nipple and are made from different materials. We offer wholesale pup joint nipple to create a smooth channel for the pipe systems in both commercial and residential areas.

The materials used depend on the type of fluids it will convey. One of the more commonly used types is PVC fittings. Features of the PVC pipe fittings that make an appropriate is the allowance for a smoother wall surface which decreases resistance to the flow. It is also lightweight and cost-effective.

On the other hand, copper fittings are corrosion-resistant. As such, they have a higher tolerance to external factors. That makes copper pipe fittings a good option to adopt for underground plumbing.

Apart from materials, there are also other components of the pipe fittings to note. P-traps prevent odor by retaining a small pool of water to stop sewer gases from entering the bathroom. Pipe caps cover the end of pipes to stop the fluid flow and protect pipe threads.

The usage of the pipes plays a crucial role in the materials suitable. For manufacturing, pipes will need to be able to withstand the fluids conveyed. We provide solutions from pipe bends to copper pipe compression fittings for any piping system required.

Pipe system involves various components, including joint nipple and are made from different materials. We offer wholesale joint nipple to create a smooth channel for the pipe systems in both commercial and residential areas.

The materials used depend on the type of fluids it will convey. One of the more commonly used types is PVC fittings. Features of the PVC pipe fittings that make an appropriate is the allowance for a smoother wall surface which decreases resistance to the flow. It is also lightweight and cost-effective.

On the other hand, copper fittings are corrosion-resistant. As such, they have a higher tolerance to external factors. That makes copper pipe fittings a good option to adopt for underground plumbing.

Apart from materials, there are also other components of the pipe fittings to note. P-traps prevent odor by retaining a small pool of water to stop sewer gases from entering the bathroom. Pipe caps cover the end of pipes to stop the fluid flow and protect pipe threads.

The usage of the pipes plays a crucial role in the materials suitable. For manufacturing, pipes will need to be able to withstand the fluids conveyed. We provide solutions from pipe bends to copper pipe compression fittings for any piping system required.

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This website is using a security service to protect itself from online attacks. The action you just performed triggered the security solution. There are several actions that could trigger this block including submitting a certain word or phrase, a SQL command or malformed data.

OCTG Pup Joints is one kind of common accessories for connection with casing and tubing. Threaded pup joints are divided into male threaded ends, single male threaded and Female threaded. The size and material is the same as the casing or tubing.

China N80 Pup Joint Manufacturer Derbo Supplies N80 Pup Joint, Hot Rolled, 1.66 Inch, EUE 2.40lb/ft, Oiled, Painting Finish, for Oil & Gas Industries.

If a polished bore receptacle completion is desired then there is no need for a tailpipe unless it is considered necessary to have a means of obtaining pressure isolation beneath the polished bore receptacle in the event of a workover or to allow retrievable downhole pressure and temperature gauges to be installed.

The height of the tailpipe above the perforated interval depends upon whether it is intended to run wireline surveys across the perforated interval. If downhole surveys are required the base of the tailpipe should be set 150 ft above the top perforations or alternatively 30 ft if no surveys are intended.

Normally if wireline work is envisaged a wireline entry guide (WEG) is installed at the base of the tailpipe. If a landing nipple for gauges is to be installed then a 30 ft pump joint is located above the WEG and above this the landing nipple and the perforated flow tube to allow fluid entry into the production string.

If required the nipple will be installed above the perforated joint. If a selective nipple system is used and the well depth exceeds 7000 ft, a 30 ft pup joint would be located beneath this nipple. In addition, if a permanent packer is installed, a millout extension would be fitted. Finally if a locator seal assembly is to be used and an extended length seal bore is required, the sealbore extension would be fitted above the millout extension, beneath the packer.

Packer plug, pump-out and push-out plugs are used to temporarily isolate the tubing. Both the pump-out and push-out plugs are run with the packer, while the packer plug can be set when the packer has been previously set and retrieved with a work string.

The most commonly used circulation devices are the ported nipple, SPM and SSD. Difficulties experienced with well deviations and seal failure has led in considered cases to their elimination from completion strings, with dependence being placed on tubing punching or coiled tubing.

The majority of wells will include at least one landing nipple in the completion string. This is usually a "no-go" nipple at the bottom of the well conduit (string), where it may be used for:

Landing nipples may incorporate ports to provide tubing/annulus communication. Flow through the ports is governed by wireline run tools (separation sleeves, side door chokes), which are landed and locked in the nipple profile.

Slip, packer and collar type lock mandrels may be used where no landing nipples are available, however, the permissible differential pressure needs to be carefully analysed.

The basic choice between nipple systems is whether a no-go or selective nipple design is chosen. If a no-go nipple system is used then its use is checked by reference to a production performance optimisation package to calculate the effect on pressure loss of the reduced bore of the no-go shoulder. If it represents a major restriction to flow, the installation of flow couplings around the nipple is recommended. The bore of the nipple selected must be smaller than the smallest nipple bore used higher up the string, e.g. there must be sequential nipple bore reduction.

If a selective nipple is considered, then it will offer the capability to set the nipple size equal to the minimum nipple bore used higher up the string. The major problems identified with selective nipples are:

In deep wells, e.g. greater than 7000 ft, cable stretch may pose a problem in identifying exact nipple locations. For such cases, a minimum nipple spacing of 30 ft is recommended.

landing nipple requirements for flowing surveys vs. packer/collar/slip mandrels (Production Operations Well Services Guide, Well intervention activities - Document 2: Wireline operations);

SPMs are fitted in the well conduit where it is necessary to install a valve that will provide communication between the tubing and the annulus. The valves may be installed/retrieved by wireline or coiled tubing techniques.

A V-shaped locator with a grooved extension provides for continued orientation while moving the kick-over tool with side-pocket equipment. Equipment entry into the side-pocket before the orienting finger leaves the groove provides optimum installation conditions.

Sliding sleeves (also referred to as Sliding Side Doors, SSDs) are part of the tubing string and provide communication between the well production conduit and various annulus Various applications include: fluid displacement; selective testing, treating or producing multiple zones; commingled production; well killing (by fluid circulation); kicking off wells (gas lift); pressure equalisation; ·chemical injection.

Jar up to open sleeves, as opposed to jar down to open, have the advantage that a greater force can usually be exerted by upward jarring especially using hydraulic or spring jars. Downward jarring force, especially in deviated wells, is somewhat limited. Where a large differential pressure, annulus to tubing, is expected, down to open sleeves may be preferable, which place the tool below the communication port preventing tools being blown up the tubing.

Most sliding sleeves incorporate landing profiles, enabling a selection of control devices, including straddle tools to isolate a leaking sleeve, to be locked in.

The sliding side door is preferable to a ported nipple or a SPM if high circulation rates are required, e.g. well killing. However, the SSD should not be considered for use without careful analysis when:

Do not install sliding sleeves opposite perforations unless it is unavoidable. Ensure there is at least 6 ft between blast joints and sliding sleeves.

There are usually wireline run/retrieved calibrated orifices to restrict fluid flow in the tubing. During the design stage appropriate landing nipples have to be selected and located for the installation of chokes and regulators to:

These can be of two types; one that is manually adjusted to help in spacing out, usually below packers in dual or triple completions, and one that allows limited tubing movement to facilitate making-up below multiple string packers and to allow for setting tandem hydrostatic packers.

These are used between packers in dual and triple completions and in selective completions using hydrostatic single-string packers. The shear pin safety joint is a device that enables stuck tubing to be sheared off, but because it introduces a weak point, its use should be restricted wherever possible.

Tubing cutters can be used to cut the tubing at any desired depth in most wells, but where sand production is a problem, possibly preventing the cutter reaching the desired depth, a safety joint could be considered.

These are important aspects of life-of-the-well completion planning. They are designed to inhibit the effects of corrosion/erosion caused by flow turbulence and jetting actions.

Blast joints are used in the tubing string opposite the perforations in producing zones where the jetting action of fluid can erode the outside of the tubing.

Flow couplings should be considered in high rate gas wells above and below completion accessories which restrict the tubing or induce turbulence, such as SSSVs and side pocket mandrels (SPMs).

They are used to centralise blast joints in the casing, particularly in deviated wells. They should be installed at least every 40 ft (12 m) (or part of 40 ft) of the blast joints.

Tubing shoes (or "mule" shoes) are short, cut-away lengths of tubing fitted to the bottom end of a tubing string to facilitate stabbing into a packer or packers. The outside should be barrel shaped to aid entry into the packer bore and to prevent hold-ups when running, and the inside bottom edge should be chamfered to aid wireline re-entry. When the tubing string is stepped down in diameter below the packer, some form of centraliser(s) should be fitted to, or near the shoe, especially in deviated wells.

This tool is designed specifically to eliminate or reduce paraffin (wax) and scale. The magnetic flux created by the tool, located within the well conduit near the reservoir, conditions the produced fluids such that scale and wax do not form within the tubing.

A number of manufacturers/supplies can now offer PDG systems. The systems vary depending on the application (e.g. fibre optic system, retrievable sensors, etc.) and overall requirements (e.g. reservoir management, ESP control, flow control, etc.). Reliability of PDG systems is a concern (75% probability of surviving for five years after installation, most failure occuring immediately after installation).

The distance between the closest perforations of adjacent zones should preferably be more than 30 ft, to allow for packer, packer accessories and blast joint positioning.

Experienced and competent wireline operators should be capable of locating a landing nipple within 0.1 to 0.2% of its actual depth. The minimum recommended distance between landing nipples, therefore is:

7" tubing, utilised to minimise pressure drop, reduces the number of wells required and defers compression. Low fluid velocities minimise potential erosion/corrosion problems at high flow rates.

The lower sliding sleeve provides an alternative flow path if the plug becomes stuck in the "R" nipple. The upper sliding sleeve gives a large port area for routine well killing. It is positioned above the chemical injection side-pocket mandrel to avoid corrosion and inhibitor deposits in the annulus.

The packer is set in 95/8" casing as it backs-up liner lap. A contingency completion with the addition of a 7" "SAB" packer and anchor latch permits the liner lap to be straddled.

The tubing collapse resistance exceeds the worst design case by factor of 1.1 (tubing pressure zero, annulus liquid filled, plus maximum surface casing head pressure).

Note that this design could be challenged, for example, why not a monobore completion, why not 13 Cr tubulars to surface, what type of VAM connection, etc.

Casing pup joint is mainly used to adjust the height of the casing strings. It is also used to adjust the depth of down-hole tools. Our pup joints are manufactured in accordance with the API Spec5CT specification. The steel grades of the products of this kind are J55, K55, N80 and L80 P110. These products feature high corrosion resistance and long running life. As a pup joints supplier, we also produce the API 5CT tubing pup joint which is the fitting of the tubing strings. And we promise that all our ...

It is produced according to API 5CT Specification. Our precision-engineered pup Joints are ideal for spacing out down-hole assemblies and handling the production of tubing accessories. As a tubing pup joints manufacturer in China, we also provide API 5CT casing pup joint which is the accessory of the casing strings ...

Pup joint is a common fitting used in industry pipeline connection. It is a section of pipe of non-standard length used for making up a string of tubular to an exact total length. This product is a one-piece construction made from alloy steel. It features wing union end connections which eliminate the need for welds and threads. This pipe fitting is capable of bearing diverse fluids and working pressures. Our products in this category include tubing pup joints and the ones for casing pipe.

3.This product has undergone phosphating and copper coating treatment. It has superior anti-abrasion properties and its thread has good anti-adhesion performance.

1.Pup joint is mainly used to correct the overall length of a drill string to land at a specific depth while staying within the working area of the valve.

2.This pipe fitting is used to achieve precise depth readings in a well for various purposes, such as setting valves, nipples, packers circulating sleeves, etc.

As a pup joints supplier in China, Hebei Xinlian (Beijing) Petroleum Pipe Co., Ltd. possesses an advanced process line of pipes for petroleum which consists of first-rate CNC thread cutting machine, automatic screw machine, hydraulic press, jet printing equipment, etc. Our products have been exported to many countries, such as Germany, Japan, Rumania, Czech, Italy, UK, Austria, Switzerland, the US, Argentina and Singapore.

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The occurrence of human T-cell leukemia virus type I (HTLV-I) is endemic in parts of southwestern Japan,66., 105., 207., 450. the Caribbean, South America,156 and sub-Saharan Africa. HTLV-I is associated with adult T-cell leukemia/lymphoma and a chronic condition with progressive neuropathy. The progressive neuropathy is called HTLV-I associated myelopathy or tropical spastic paraparesis.136 Other illnesses have been reported in association with HTLV-I infection including dermatitis, uveitis, arthritis, Sjögren syndrome in adults, and infective dermatitis and persistent lymphadenitis in children. Transmission of HTLV-I occurs most often through sexual contact, via blood or blood products, and via breast milk. Infrequent transmission does occur in utero or at delivery and with casual or household contact.291

Seroprevalence generally increases with age and varies widely in different regions and in populations of different backgrounds. In some areas of Japan, seropositivity can be as high as 12% to 16%, but in South America, Africa, and some Caribbean countries the rates are 2% to 6%. In Latin America seropositive rates can be as high as 10% to 25% among female sex workers or attendees to STD clinics.156 In blood donors in Europe, the seroprevalence of HTLV-I has been reported at 0.001% to 0.03%. The seroprevalence in pregnant women in endemic areas of Japan is as high as 4% to 5% and in nonendemic areas as low as 0.1% to 1.0%. HTLV-1 is not a major disease in the United States. In studies from Europe the seroprevalence in pregnant women has been noted to be up to 0.6%. These pregnant women were primarily of African or Caribbean descent.138

HTLV-I antigen has been identified in breast milk of HTLV-I positive mothers.220 Another report shows that basal mammary epithelial cells can be infected with HTLV-I and can transfer infection to peripheral blood monocytes.254 Human milk from HTLV-I positive mothers caused infection in marmosets.221., 453. HTLV-I infection clearly occurs via breastfeeding and a number of reports document an increased rate of transmission of HTLV-I to breastfed infants compared with formula-fed infants.12., 13. in two separate reports demonstrated a parallel decline in antibodies against HTLV-I in both formula-fed and breastfed infants to a nadir at approximately 1 year of age and a subsequent increase in antibodies from 1 to 2 years of age. The percentage of children seropositive at 1 year of age in the breastfed and formula-fed groups, respectively, was 3.0% and 0.6%, at 1.5 years of age it was 15.2% and 3.9%, and at 2 years of age it was 41.9% and 4.6%. A smaller group of children followed through 11 to 12 years of age demonstrated no newly infected children after 2 years of age and no loss of antibody in any child who was seropositive at 2 years of age.12., 13.

Other factors relating to HTLV-I transmission via breast milk have been proposed. Yoshinaga et al460 presented data on the HTLV-I antigen producing capacity of peripheral blood and breast milk cells and showed an increased mother-to-child transmission rate when the mother’s blood and breast milk produced large numbers of antigen-producing cells in culture.460 Hisada et al183 reported on 150 mothers and infants in Jamaica, demonstrating that a higher maternal provirus level and a higher HTLV-I antibody titer were independently associated with HTLV-I transmission to the infant. Ureta-Vidal et al421 reported an increased seropositivity rate in children of mothers with a high proviral load and elevated maternal HTLV-I antibody titers.

Various interventions have been proposed to decrease HTLV-I transmission via breastfeeding. Complete avoidance of breastfeeding was shown to be an effective intervention by Hino et al180., 181. in large population of Japanese in Nagasaki. Avoiding breastfeeding led to an 80% decrease in transmission. Breastfeeding for a shorter duration is another effective alternative. Ando et al11 showed that freezing and thawing breast milk decreased the infectivity of HTLV-I. Sawada et al363 demonstrated in a rabbit model that HTLV-I immunoglobulin protected against HTLV-I transmission via milk. It is reasonable to postulate that any measure that would decrease the maternal provirus load or increase the anti-HTLV-I antibodies available to infants might decrease the risk for transmission. The overall prevalence of HTLV-I infection during childhood is unknown because the majority of individuals do not manifest illness until much later in life. The timing of HTLV-I infection in a breastfeeding population has been difficult to assess because of passively acquired antibodies from the mother and issues related to testing. Furnia et al139 estimated the time of infection for a cohort of 16 breastfed infants in Jamaica. The estimated median time of infection was 11.9 months as determined by PCR compared with the estimated time of infection, based on whole virus Western blot, of 12.4 months.

In areas where the prevalence of HTLV-I infection (in the United States, Canada, or Europe) is rare, the likelihood that a single test for antibody against HTLV-I would be a false positive test is high compared with the number of true positive tests. Repeat testing is warranted in many situations.66 Quantification of the antibody titer and the proviral load is appropriate in a situation when mother-to-child transmission is a concern. A greater risk for progression to disease in later life has not been shown for HTLV-I infection through breast milk, but early-life infections are associated with the greatest risk for adult T-cell leukemia.402 The mother and family should be informed about all these issues. If the risk for lack of breast milk is not too great and formula is readily available and culturally acceptable, then the proscription of breastfeeding, or at least a recommendation to limit the duration of breastfeeding to 6 months or less, is appropriate to limit the risk for HTLV-I transmission to the infant. Freezing and thawing breast milk before giving it to an infant might be another reasonable intervention to decrease the risk for transmission, although no controlled trials document the efficacy of such an intervention. Neither Ig nor antiviral agents against HTLV-I are available at this time.

Human T-cell leukemia virus type II (HTLV-II) is endemic in specific geographic locations, including Africa, the Americas, the Caribbean, and Japan. Transmission is primarily through intravenous drug use, contaminated blood products, and breastfeeding. Sexual transmission occurs but its overall contribution to the prevalence of HTLV-II in different populations remains uncertain. Many studies have examined the presence of HTLV-I and II in blood products. PCR testing and selective antibody tests suggest that about half of the HTLV seropositivity in blood donors is caused by HTLV-II.

HTLV-II has been associated with two chronic neurologic disorders similar to those caused by HTLV-I, tropical or spastic ataxia.258 A connection between HTLV-II and glomerulonephritis, myelopathy, arthritis, T-hairy cell leukemia, and large granulocytic leukemia has been reported.

Mother-to-child transmission has been demonstrated in both breastfed and formula-fed infants. It appears that the rate of transmission is greater in breastfed infants.174 Nyambi et al304 reported that HTLV-II transmission did correlate with the duration of breastfeeding. The estimated rate of transmission was 20%. The time to seroconversion (after the initial loss of passively acquired maternal antibodies) for infected infants seemed to range between 1 and 3 years of age.304 At this time avoidance of breastfeeding and limiting the duration of breastfeeding are the only two possible interventions with evidence of effectiveness for preventing HTLV-II mother-to-child transmission.207

With the current understanding of retroviruses, it is appropriate in cases of documented HTLV-II maternal infection to recommend avoiding or limiting the duration of breastfeeding and provide alternative nutrition when financially practical and culturally acceptable. Mothers should have confirmatory testing for HTLV-II and measurement of the proviral load. Infants should be serially tested for antibodies to HTLV-II and have confirmatory testing if seropositive after 12 to 18 months of age. Further investigation into the mechanisms of transmission via breast milk and possible interventions to prevent transmission should occur as they have for HIV-1 and HTLV-I.

Human immunodeficiency virus type 1 (HIV-1) is transmitted through human milk. Refraining from breastfeeding is a crucial aspect of preventing perinatal HIV infection in the United States and many other countries. The dilemma is the use of replacement feeding versus breastfeeding in countries where breastfeeding provides infants with significant protection from illness and death due to malnutrition or other infections.

More than 90% of children younger than 13 years old infected with HIV-1 have been infected by mother-to-child transmission. The number of children estimated to be living with HIV increased to 2 million in 2007 (estimate range 1.9 to 2.3 million).419

The WHO estimates that 2.7 million people were newly infected with HIV-1 in 2007, with children younger than 14 years old making up 370,000 of that 2.7 million. (This number has declined due to increasing access to interventions to prevent mother-to-infant transmission. Availability of antiretroviral therapy for prevention of mother-to-child HIV transmission in developing countries in 2007 was estimated to reach 33% of the mothers who needed it.)419

The evidence of HIV transmission via breastfeeding is irrefutable. Multiple publications summarize the current evidence for HIV transmission via breastfeeding in the literature.232., 341., 420. Since 1985, case reports have documented HIV transmission via breast milk to children around the world.182., 198., 249., 465. Primary HIV infection in breastfeeding mothers, with the concomitant high viral load, is associated with a particularly high rate of HIV transmission via breast milk. Palasanthiran et al322 estimated that risk at 27%.Large observational studies have demonstrated higher rates of HIV transmission in breastfed infants of mothers with chronic HIV infection compared with formula-fed infants.43., 108., 124. A systematic analysis of published reports estimated the additional risk for perinatal HIV transmission due to breastfeeding to be 14% (95% confidence interval 7% to 22%).117 More recently published cohort studies similarly attributed additional risk for HIV transmission due to breastfeeding at 4% to 22% over and above the risk from prenatal and intrapartum transmission.38., 104., 121. Laboratory reports demonstrate the presence of cell-free virus and cell-associated virus in breast milk as well as various immunologic factors that could block or limit infection.335., 345., 351., 373.

Many of the potential risk factors associated with human milk transmission of HIV have been described. The cumulative risk for HIV transmission is higher the longer the duration of breastfeeding.108., 251., 282., 290., 424. Maternal characteristics related to transmission of HIV via human milk include younger maternal age, higher parity, lower CD4+ counts, higher plasma viral loads, and breast abnormalities (mastitis, abscess, or nipple lesions). Characteristics of human milk that relate to a higher risk for transmission include higher viral load in the milk, lower concentrations of antiviral substances (lactoferrin, lysozyme), and lower concentrations of virus-specific cytotoxic T-lymphocytes, levels of various interleukins (IL-7, IL-15),434., 435. secretory IgA, and IgM. Mixed breastfeeding is also associated with a higher risk for HIV transmission compared with exclusive breastfeeding.99., 100., 410. The measurable benefits of breast milk versus the relative risk for HIV transmission to the infant due to exclusive breastfeeding (with optimization of other factors to decrease HIV transmission) have been reported in a couple of studies.97., 229. The measurable benefits of receiving breast milk versus the relative increased risk for HIV transmission will need to be determined in a prospective fashion in different locales.247

). The simplest and most effective is the compete avoidance of human milk. This is a practical solution in places like the United States and other countries where replacement feeding as well as other strictly medical interventions are feasible and reasonable, and the risk for not providing breast milk to the infant is negligible. In resource-poor situations, where the risk for other infections is high without the benefits of breast milk, exclusive breastfeeding is appropriate, with any other reasonable and culturally acceptable interventions to decrease HIV transmission via breast milk.

Women and their health care providers need to be aware of the potential risk for transmission of HIV infection to infants during pregnancy and in the peripartum period and through breast milk.

At delivery, education about HIV and testing with the consent of women whose HIV status during pregnancy is unknown are strongly recommended. Knowledge of a woman’s HIV status assists in counseling on breastfeeding and helps each woman understand the benefits to herself and her infant of knowing her serostatus and the behaviors that would decrease the likelihood of acquisition and transmission of HIV.

Women who are known to have HIV infections must be counseled not to breastfeed or provide their milk for the nutrition of their own or other’s infants.

In general, women who are known to be HIV seronegative should be encouraged to breastfeed. However, women who are HIV seronegative but at particularly high risk for seroconversion (e.g., injection drug users and sexual partners of known HIV-positive persons or active drug users) should be educated about HIV with an individualized recommendation concerning the appropriateness of breastfeeding. In addition, during the perinatal period, information should be provided on the potential risk for transmitting HIV through breast milk and about methods to reduce the risk for acquiring HIV infection.

Each woman whose HIV status is unknown should be informed of the potential for HIV-infected women to transmit HIV during the peripartum period and through breast milk and the potential benefits to her and her infant of knowing her HIV status and how HIV is acquired and transmitted. The health care provider needs to make an individualized recommendation to assist the woman in deciding whether to breastfeed.

Neonatal intensive care units should develop policies that are consistent with these recommendations for the use of expressed breast milk for neonates. Current standards of the U.S. Occupational Safety and Health Administration (OSHA) do not require gloves for the routine handling of expressed human milk. However, health care workers should wear gloves in situations in which exposure to breast milk might be frequent or prolonged, such as in milk banking.

Human milk banks should follow the guidelines developed by the U.S. Public Health Service, which include screening all donors for HIV infection, assessing risk factors that predispose to infection, pasteurizing all milk specimens.

From Lawrence RA: A review of the medical benefits and contraindications to breastfeeding in the United States. In Maternal and Child Health Technical Information Bulletin, Washington, DC, 1997, U.S. Health Resources and Services Administration.

Potentially effective interventions include exclusive breastfeeding, early weaning versus breastfeeding for longer durations, education, and support to decrease the likelihood of mastitis or nipple lesions.191 Other possible interventions include treating a mother with antiretroviral therapy for her own health (CD4 counts less than 350) or prophylactically to decrease the human milk viral load, treating an infant prophylactically for a prolonged period of time (6 weeks to 6 months) to protect against transmission via breastfeeding, treating the milk itself to decrease the viral load (by pasteurization or other methods),316., 318. treating acute conditions in mothers and infants (e.g., mastitis, breast lesions, infant candidiasis), and enhancing an infant’s own defenses via vitamins, immunization, or antiretroviral therapy. Some of these may not be feasible in certain settings such as pasteurization or maternal antiretroviral therapy. Others may not be culturally acceptable, such as treating expressed breast milk before giving it to an infant or even exclusive breastfeeding.

Significant data demonstrate the advantage of breastfeeding, even for HIV-infected or HIV-exposed infants. The complete avoidance of breastfeeding in certain situations may lead to increased risk for illness and death due to other reasons besides HIV transmission.106 A study from Kenya showed improved HIV-1-free survival rates in a formula-fed group of children born to HIV-positive mothers, but the breastfed and formula groups had similar mortality rates (24.4% versus 20.0%, respectively) and similar incidences of diarrhea and pneumonia in the first 2 years of life.272 No difference in the two groups was seen in the prevalence of malnutrition, but the breastfed infants had better nutritional status in the first 6 months of life. Arpadi et al20 recommend additional nutritional interventions to complement breastfeeding in this population after 6 months of age. Two reports from Zambia document the benefit of exclusive breastfeeding for decreasing late HIV transmission and the lower mortality at 12 months in infants who had continued breastfeeding rather than had discontinued breastfeeding at 4 months of age.229., 385. In Malawi, HIV-infected and HIV-exposed infants who were breastfed (exclusive breastfeeding for 2 months and mixed feeding after that) had lower mortality at 24 months than those who were not breastfed.405 A report from Botswana examined breastfeeding plus infant zidovudine prophylaxis for 6 months versus formula feeding plus infant zidovudine for 1 month; this study showed a decreased risk for vertical transmission with formula feeding, but also increased cumulative mortality for the HIV-infected infants at 7 months of age who were in the formula-fed group.411 A study from South Africa examining the use of vitamin A also demonstrated less morbidity in HIV-infected children who were breastfed than not breastfed.102 Other abstract reports have shown increased morbidity in HIV-infected children due to diarrhea, gastroenteritis, and hospitalization after weaning from breastfeeding.205., 226., 315., 413.

Exclusive breastfeeding in most areas of the world is essential to infant health and survival, even in the situation of maternal HIV infection.97., 99., 100., 229. The duration of exclusive breastfeeding is crucial to decreasing the risk for HIV infection in infants versus the risk for malnutrition and other infections with early weaning. In the Mashi Study in Botswana, Thior et al411 evaluated infants randomized to breastfeeding plus infant zidovudine for 6 months or formula feeding plus 1 month of infant zidovudine. The cumulative infant mortality was significantly higher at 7 months for the formula-fed group but at 18 months it was similar between the two groups. The breastfed infants were more likely to become HIV infected despite the 6 months of zidovudine prophylaxis.411 Becquet et al33 analyzed data from Cote d’Ivoire for 2001 to 2005; 47% of the HIV-exposed infants were breastfed for a median of 4 months, and 53% were formula fed and observed for 2 years. No significant difference in the rate of HIV infection was seen in the two groups, and no significant difference between the two groups was seen for morbid events (diarrhea, acute respiratory infections or malnutrition) or hospitalization or death. The authors attributed these good outcomes to effective nutritional counseling and care, access to clean water, and the provision of a safe and continuous supply of breast milk substitute.33 Coovadia et al97 studied exclusive breastfeeding in the first 6 months of life as an intervention in South Africa. Of the exclusively breastfed infants, 14.1% at 6 weeks of age and 19.5% at 6 months of age were HIV infected. Breastfed infants who also were fed solids or formula milk were more likely to acquire infection than exclusively breastfed infants. The cumulative mortality at 3 months of age was markedly lower for exclusively breastfed infants (6.1%) versus 15.1% in the infants receiving mixed feedings.

Kuhn et al230 examined the effects of early, abrupt weaning on HIV-free survival of 958 children in Zambia. Infants were randomly assigned to two different counseling programs that advised either abrupt weaning at 4 months or prolonged breastfeeding. In the weaning intervention group, 69% of mothers stopped breastfeeding by 5 months compared with a median duration of breastfeeding of 16 months in the control group. The study found no significant difference in HIV-free survival at 24 months in the two groups (83.9% versus 80.7%). Children already infected by 4 months of age had a higher mortality if they were assigned to the early weaning group (73.6% versus 54.8%). Additional analysis showed that in mothers with less severe HIV disease early weaning was clearly harmful to the infant.231 Arpadi et al20 studied the growth of HIV-exposed, uninfected children who were exclusively breastfed for 4 months with rapid weaning to replacement foods or exclusively breastfed until 6 months and then continued breastfeeding with complementary foods. Weight-for-age z scores dropped markedly in both groups from 4 to 15 months of age but less so in the continued breastfeeding group. Length-for-age z score also dropped dramatically, but was not influenced by continued breastfeeding. Even in this HIV-exposed, uninfected group of children, additional nutritional interventions are essential to complement breastfeeding beyond 6 months of age.20

In recent years the discussion around preventing HIV transmission via breastfeeding and in the number of studies examining the important issues have increased.98., 233., 283. The fact that intrapartum and perinatal transmission of HIV from mothers to infants has decreased markedly due to the increased utilization of antiretroviral therapy during pregnancy, delivery, and postnatally for prevention emphasizes the importance of now working harder to decrease breast milk transmission of HIV. In considering different possible interventions to decrease mother-infant HIV transmission, it is crucial to reemphasize the goals of optimizing maternal health and survival and optimizing infant health and survival at the same time.

A laboratory report shows that mothers receiving highly active antiretroviral therapy (HAART) while breastfeeding do have decreased whole breast milk HIV-1 viral loads (23/26 mothers had less than 50 copies/mL) compared with mothers who did not receive HAART (9/25 with less than 50 copies/mL). However, the whole milk HIV-1 DNA load (measured as “undetectable” at less than 10 copies/106 cells) was not significantly different in the HAART (13 of 26 mothers)] and non-HAART (15 of 23) groups.378 HIV-1 DNA is incorporated into cells found in breast milk. Another group showed significantly lower HIV RNA levels in the breast milk of women treated with nevirapine, zidovudine, and lamivudine compared with women not receiving antiretroviral therapy.152

The use of maternal HAART seems to decrease HIV-1 transmission via breastfeeding. One group working in Mozambique, Malawi, and Tanzania working with mother-infants pairs receiving HAART as prevention during pregnancy compared one cohort (809 mother-infant pairs) who received supplementary formula and water filters for the first 6 months of life with a second cohort (251 mother-infant pairs) breastfeeding exclusively and the mothers receiving HAART for the first 6 months. The cumulative incidence rate of HIV infection at 6 months of age was 2.7% for the formula-fed infants and 2.2% for breastfed infants. Through 6 months of age no apparent additional risk for late postnatal transmission of HIV was observed.323 The Petra study team working in Tanzania, South Africa, and Uganda examined the efficacy of three short-course regimens of zidovudine and lamivudine in preventing early and late HIV transmission in this predominantly breastfeeding population.332 There were four regimens: A, zidovudine and lamivudine starting at 36 weeks’ gestation plus intrapartum medication and 7–days’ postpartum treatment; B, same as A without the prepartum component; C, intrapartum zidovudine and lamivudine only; D, placebo. At week 6 the HIV transmission rates were 5.7% in group A, 8.9% in group B, 14.2% in group C, and 15.3% in group D. At 18 months the HIV infection rates were 15% in group A, 18% in group B, 20% in group C, and 22% in group D. Although a measurable decrease in transmission at 6 weeks of age was observed, limited protection was seen at 18 months of age. An observational study from Tanzania compared maternal HAART for 6 months with exclusive breastfeeding and abrupt weaning at 5 to 6 months of age with a historical control of the same feeding schedule without the postnatal maternal HAART. In the treatment group the cumulative HIV transmission was 4.1% at 6 weeks, 5.0% at 6 months, and 6.0% at 18 months of age. The cumulative HIV infection or death rate was 8.6% at 6 months and 13.6% at 18 months of age. The cumulative risk for HIV transmission was 1.1% between 6 and 18 months. The HIV transmission in this treatment group was half the transmission rate in the historical control group.218 Another study in sub-Saharan Africa with 6 months of maternal HAART and exclusive breastfeeding for 6 months demonstrated 94% HIV-free survival at 12 months of age; the maternal and infant mortality rates for the treated mother-infant pairs were significantly lower than the country’s maternal and infant mortality rates.264

Antiretroviral therapy prophylaxis for infants is another investigated intervention to decrease HIV transmission via breastfeeding. In a study from Cote d’Ivoire comparing different groups over time, infants received zidovudine (ZDV) alone as ZDV prophylaxis, a single dose of nevirapine (NVP) and 7 days of zidovudine (ZDV) as NVP/ZDV prophylaxis, or a single dose of nevirapine plus zidovudine and lamivudine (3TC) for 7 days as NVP/ZDV/3TC prophylaxis. Formula feeding (FF) was compared with exclusive shortened breastfeeding (ESB) upto 4 months of age and prolonged breastfeeding (PB). The cumulative transmission rates at 18 months were 22.3% in 238 infants in the ZDV + PB group, 15.9% in 169 infants in the NVP/ZDV + ESB group, 9.4%, in the 195 infants in the NVP/ZDV +FF group, 6.8% in the 198 infants in the NVP/ZDV/3TC + ESB group, and 5.6% in the 126 infants in the NVP/ZDV/3TC + FF group.252 Kumwenda et al235 working in Malawi demonstrated decreased HIV transmission with breastfeeding and two different infant prophylaxis regimens. At 9 months of age, they observed a 10.6% occurrence of HIV transmission for infants receiving a single dose of nevirapine plus 1 week of zidovudine compared with 5.2% in the group receiving a single dose of nevirapine plus 1 week of zidovudine plus 14 weeks of daily nevirapine, and 6.4% in the group receiving a single dose of nevirapine plus 1 week of zidovudine plus 14 weeks of nevirapine and zidovudine.235 In the Mitra Study in Tanzania in which the median time of breastfeeding was 18 weeks, the HIV transmission rate at 6 months in the infants who received zidovudine plus 3TC for 1 week plus 3TC alone for breastfeeding through 6 months of age was less than 50% of the transmission rate for those infants receiving only 1 week of zidovudine plus 3TC.217 A summary of three trials in Ethiopa, India, and Uganda compared a single dose of nevirapine at birth for infants with 6 weeks of daily nevirapine in predominantly breastfed infants whose mothers were counselled regarding feeding per the WHO/UNICEF guidelines. At 6 months 87 of 986 infants in the single-dose group and 62 of 901 in the extended-dose group were HIV infected, which was not statistically significant. The authors suggested that a longer course of infant antiretroviral prophylaxis might be more effective.388

The potential effect of breastfeeding on the HIV-positive mother needs to be adequately assessed in relation to the mother’s health status. From Uganda and Zimbabwe Mbizvo et al271 reported no difference in the number of hospital admissions or mortality between HIV-positive and HIV-negative women during pregnancy. In the 2 years after delivery the HIV-positive women had higher hospital admission (approximately two times increased risk) and death rates (relative risk greater than 10) than HIV-negative women.271 Chilongozi et al90 reported on 2292 HIV-positive mothers from four sub-Saharan sites followed for 112 months. Serious adverse events occurred in 166 women (7.2%); 42 deaths occurred in the HIV-positive women, and no deaths occurred in 331 HIV-negative women.90

Several studies have examined breastfeeding relative to mothers’ health and reported conflicting results. The first study from Kenya demonstrated a significantly higher mortality rate in breastfeeding mothers compared with a formula-feeding group in the 2 years after delivery. The hypothesized explanation offered by the authors for this difference was increased metabolic demands, greater weight loss, and nutritional depletion.294 A second study from South Africa showed an overall lower mortality rate in the two groups with no significant difference in mortality rate in the 10 months of observation.101 Kuhn et al227 reported no difference in mortality at 12 months after delivery between 653 women randomly assigned to a short breastfeeding group (326 women, median breastfeeding duration 4 months, 21% still breastfeeding at 12 months) and a long breastfeeding group (327 women, 90% breastfeeding at 5 months, 72% breastfeeding at 12 months, median 15 months). The HIV-related mortality rates were high (4.9%), but not associated with prolonged lactation.227 Walson et al433 followed 535 HIV-positive women for 1 to 2 years in Kenya. The mortality risk was 1.9% at 1 year and 4.8% at 2 years of follow-up. Although less than 10% of women reported a hospitalization during the 2 years, they experienced various common infections (pneumonia, diarrhea, TB, malaria, STDs, urinary tract infections, mastitis). Breastfeeding was a significant cofactor for diarrhea and mastitis but not for pneumonia, TB, or hospitalization.433

In summary, breastfeeding of infants by HIV-positive mothers does lead to an increased risk for HIV infection in the infants. Much remains to be understood about the mechanisms of HIV transmission via breast milk and the action and efficacy of different interventions to prevent such transmission. The complete avoidance of breastfeeding is a crucial component for the prevention of perinatal HIV infection in the United States and many other countries.

In resource-poor settings, where breastfeeding is the norm and where it provides vital nutritional and infection protective benefits, the WHO, UNICEF, and the Joint United Nations Programme on HIV/AIDS (UNAIDS) recommend education, counseling, and support for HIV-infected mothers so they can make an informed choice concerning infant feeding. Mothers choosing to breastfeed should receive additional education, support, and medical care to minimize the risk for HIV transmission and to optimize their own health status during and after breastfeeding. Mothers choosing to use replacement feedings should receive parallel education, support, and medical care for themselves and their infants to minimize the effect of the lack of breastfeeding.

Good evidence now shows that antiretroviral prophylactic regimens for mothers or infants while continuing breastfeeding does decrease postnatal HIV transmission. Early weaning is associated with increased morbidity and mortality. Further carefully controlled research is indicated to adequately assess the risks and benefits to infants and mothers of prolonged breastfeeding with antiretroviral prophylaxis for either or both mothers and infants. Along with this, HIV testing rates must be improved at the same time as increased availability and access to antenatal care, HIV prevention services, and HIV medical care for everyone must be increased. The availability and free access to antiretroviral medications must also improve.

The decision about infant feeding for HIV-positive mothers remains a difficult one, but this is slowly changing with increasing options. The goals remain 100% HIV transmission prevention, optimal maternal health and survival, and long-term infant health and survival.

HIV-2 is endemic in western Africa and parts of the Caribbean and found infrequently in Europe and North and South America.190., 305. It is transmitted via sexual contact, blood, or blood products and from mother to child.

Routine testing for HIV-2 is recommended in blood banks. Antibody tests used for HIV-1 are only 50% to 90% sensitive for detecting HIV-2.65 Specific testing for HIV-2 is appropriate whenever clinically or epidemiologically indicated.

Vertical transmission occurs infrequently. Ekpini et al121 followed a large cohort of west African mothers and infants: 138 HIV-1 positive women, 132 HIV-2 positive women, 69 women seropositive for both HIV-1 and 2, and 274 HIV seronegative women. A few cases of perinatal HIV-2 transmission occurred, but no case of late postnatal transmission was observed.121

It is probable that HIV-2 transmission via breast milk is less common than with HIV-1, but insufficient data support that the risk for transmission is zero. Mothers who test positive for HIV-2 should be tested for HIV-1, and guidelines for breastfeeding should follow those for HIV-1 until additional information is available.

Rabies virus produces a severe infection with progressive CNS symptoms (anxiety, seizures, altered mental status) that ultimately proceeds to death; few reports of survival exist. Rabies occurs worldwide except in Australia, Antarctica, and several island groups. In 1992 more than 36,000 cases of rabies were reported to the WHO, a number that is probably a marked underestimate of the actual cases.67 Between 1990 and 2003, 37 cases of human rabies were reported in the United States.70., 78. Postexposure prophylaxis is given to thousands of patients each year.

Rabies virus is endemic in various animal populations, including raccoons, skunks, foxes, and bats. Because of aggressive immunization programs, rabies in domesticated dogs and cats in the United States is uncommon. The virus is found in the saliva and tears and nervous tissue of infected animals. Transmission occurs by bites, licking, or simply contact of oral secretions with mucous membranes or nonintact skin. Many cases of rabies in humans now lack a history of some obvious contact with a rabid animal. This may be a result of the long incubation period (generally 4 to 6 weeks, but can be up to 1 year, with reports of incubation periods of several years), a lack of symptoms early in an infectious animal, or airborne transmission from bats in enclosed environments (caves, laboratories, houses).

Person-to-person transmission via bites has not been documented, although it has occurred in corneal transplants.44 Rabies viremia has not been observed in the spread of the virus. No evidence exists indicating transmission through breast milk.

In the case of maternal infection with rabies, many scenarios can occur before the onset of progressive, severe CNS symptoms. The progression and severity of maternal illness can preclude breastfeeding, but separation of an infant from the mother is appropriate regardless of the mother’s status and method of infant feeding (especially to avoid contact with saliva and tears). Breastfeeding should not continue when the mother has symptoms of rabies, and the infant should receive postexposure immunization and close observation. An infant may received expressed breast milk, but the expression must occur without possible contamination with saliva or tears from the mother.

A more common scenario is a mother’s apparent exposure to rabies (without exposure for the infant), necessitating postexposure immunization of the mother with rabies vaccine. In the majority of cases, in the absence of maternal illness, breastfeeding can reasonably continue during the mother’s five-dose immunization series in 28 days. In a rare situation in which apparent exposure of mother and infant to rabies occurs together, postexposure treatment of both mother and infant should be instituted, and breastfeeding can continue.

Respiratory syncytial virus (RSV) is a common cause of respiratory illness in children and is relatively common in adults, usually producing milder upper respiratory tract infection in adults. No evidence indicates that RSV causes intrauterine infection, adversely affects the fetus, or causes abortion or prematurity. RSV does produce infection in neonates, causing asymptomatic infection, afebrile upper respiratory tract infection, bronchiolitis, pneumonia, and apnea. Mortality rate can be high in neonates, especially in premature infants and ill full-term infants, particularly those with preexisting respiratory disease (hyaline membrane disease, bronchopulmonary dysplasia) or cardiac disease associated with pulmonary hypertension.

RSV is believed to be transmitted via droplets or direct contact of the conjunctiva, nasal mucosa, or oropharynx with infected respiratory secretions. Documentation of RSV infection is rarely made in adults, and spread from a mother or other household contacts probably occurs before a diagnosis can be made. Therefore risk for RSV transmission from breast milk is probably insignificant compared with transmission via direct or droplet contact in families. In nurseries, however, it is appropriate to make a timely diagnosis of RSV infection in neonates to isolate infants from the others and prevent spread in the nursery. Ribavirin is not recommended for routine use. It is infrequently used in patients with potentially life-threatening RSV infection.

RSV infection should be suspected in any infant with rhinorrhea, nasal congestion, or unexplained apnea, especially in October through March in temperate climates. Prophylaxis against RSV with RSV-specific immunoglobulin IV (RSV-IGIV) during this season for infants at highest risk for severe disease is appropriate.

Debate surrounds the effect of passively acquired antibodies (in infants from mothers before birth) against RSV on the occurrence and severity of illness in neonates and infants. It appears that a higher level of neutralizing antibody against RSV in neonates decreases the risk for severe RSV disease.153., 239. Some controversy remains concerning the measurable benefit of breastfeeding for preventing serious RSV disease.3., 54., 115. Some studies have shown benefit and others no effect. Controlling for possible confounding factors (e.g., smoking, crowded living conditions) in these studies has been difficult. At this point, no reason exists to stop breastfeeding with maternal RSV infection; a potential exists for benefit from nonspecific factors in breast milk against the RSV. Infants with RSV infection should breastfeed unless their respiratory status precludes it.

Rotavirus infections usually result in diarrhea, accompanied by emesis and low-grade fever. In severe infections the clinical course can include dehydration, electrolyte abnormalities, and acidosis and can contribute to malnutrition in developing countries. Generally, every child will have at least one episode of rotavirus infection by 5 years of age.157 In developed countries, rotavirus is often associated with diarrhea requiring hospitalization in children younger than 2 years of age, but rarely associated with death. Worldwide rotavirus is the leading cause of diarrhea-related deaths in children younger than 5 years old. Estimates suggest that in children younger than 5 years old rotavirus infection leads to more than 100 million occurrences of diarrhea, 2 million hospital admissions, and 500,000 deaths each year.157 Fecal-oral transmission is the most common route, but fomites and respiratory spread may also occur. Spread of infection occurs most often in homes with young children or in daycare centers and institutions. In hospitalized infants or mothers with rotavirus infection, contact precautions are indicated for the duration of the illness. No evidence indicates prenatal infection from rotavirus, but perinatal or postnatal infection from contact with the mother or others can occur.

No case of transmission of rotavirus via breast milk has been documented. Breast milk does contain antibodies to rotavirus for up to 2 years. Human milk mucin has been demonstrated to inhibit rotavirus replication and prevent experimental gastroenteritis.457 The mechanisms of rotavirus immunity are not well understood. They are thought to be multifactorial with cell-mediated immunity limiting severity and the course of infection, while humoral immunity protects against subsequent infections. Innate and adaptive responses at the level of the mucosa are probably the most important.134

Exclusive breastfeeding may decrease the likelihood of severe rotavirus-related diarrhea by as much as 90%.93., 377. Although breastfeeding does not prevent infection with rotavirus, it seems to decrease the severity of rotavirus-induced illness in children younger than 2 years old.93., 123., 184. At least one study suggested that this may represent simply the postponement of severe rotavirus infection until an older age.93 One study suggested that protection against rotavirus rapidly declines upon discontinuation of breastfeeding.356 This delay in rotavirus infection until the child is older may be beneficial in that the older child may be able to tolerate the infection or illness with a lower likelihood of becoming dehydrated or malnourished. Continuing breastfeeding during an episode of rotavirus illness with or without vomiting is appropriate and often helpful to the infant. No reason to suspend breastfeeding by a mother infected with rotavirus is apparent.

Two rotavirus vaccines (RotaTeq and Rotarix) have been licensed for use in more than 90 countries, but less than 20 countries have routine immunization programs. Additional types of rotavirus vaccines are undergoing study in various countries, specifically examining the efficacy of the vaccines in low and medium income countries.444 Some of the explanations for the slow implementation of an effective vaccine globally include differences in protection with specific vaccines in high income countries compared with low or medium income countries, the unfortunate association with intussusception in the United States, the delayed recognition of the significant rotavirus-related morbidity and mortality, and the cost of the new vaccines. The question of variable efficacy of the specific rotavirus vaccines in developed and developing countries remains an important one. Several trials are examining this issue and attempting to address factors such as maternal transplacentally transferred antibodies, breastfeeding practices (especially immediately before immunization with a live oral rotavirus vaccine), stomach acid, micronutrient malnutrition, interfering gut flora, and differences in the epidemiology of rotavirus in different locations.327 Evidence indicates that maternal immunization with rotavirus vaccine can increase both transplacental acquisition of antibodies and secretory IgA in breast milk.334 Additionally, oral rotavirus vaccines have been able to stimulate a good serologic response in both formula-fed and breastfed infants, although the antigen titers may need to be modified to create an optimal response in all infants.86 The actual protective effect of these vaccines in different situations and strategies will require measurement in ongoing prospective studies.

Congenital rubella infection has been well described, and the contributing variables to infection and severe disease have been elucidated. The primary intervention to prevent congenital rubella has been to establish the existence of maternal immunity to rubella before conception, including immunization with rubella vaccine and reimmunization if indicated. Perinatal infection is not clinically significant. Postnatal infection occurs infrequently in children younger than 1 year of age because of passively acquired maternal antibodies. The predominant age of infection is 5 to 14 years old, and more than half of those with infections are asymptomatic. Postnatal rubella is a self-limited, mild viral infection associated with an evanescent rash, shotty adenopathy, and low-grade transient fever. It most often occurs in the late winter and spring. Infants with congenital infection shed the virus for prolonged periods from various sites and may serve as a source of infection throughout the year. Contact isolation is appropriate for suspected and proved congenital infection for at least 1 year, including exclusion from day care and avoidance of pregnant women, whereas postnatal rubella infection requires droplet precautions for 7 days after the onset of rash.

Rubella virus has been isolated from breast milk after natural infection (congenital or postnatal) and after immunization with live attenuated vaccine virus. Both IgA antibodies and immunoreactive cells against rubella have been identified in breast milk. Breastfed infants can acquire vaccine virus infection via milk but are asymptomatic. Because postpartum infection with this virus (natural or vaccine) is not associated with clinically significant illness, no reason exists to prevent breastfeeding after congenital infection, postpartum infection with this virus, or maternal immunization with rubella vaccine.

Severe acute respiratory syndrome (SARS) is a term that could be applied to any acute serious respiratory illness caused by or associated with a variety of infections agents; since 2003, however, it has been linked with SARS-associated coronavirus (SARS-CoV). In the global outbreak of 2002 to 2003, more than 8400 probable cases of SARS and more than 800 deaths occurred. More than the actual number of affected individuals or its associated mortality rate (approximately 10% overall, and closer to 50% in persons older than 65 years of age), it was what we did not know about this new unusual illness, and the tremendous publicity surrounding it, that made SARS such a sensation. We now know the cause of this illness, known as the SARS-CoV. SARS-CoV was shown not to be closely related to the previously characterized coronavirus groups.265., 350. Despite intense international