- NEW YORK (Reuters
Health)- The risk of an HIV-positive mother passing the virus to her infant
via breast milk is highest in the first few months of life, according to
a study conducted in the African nation of Malawi.
- The researchers also found evidence that inexperienced
mothers may be at higher risk for transmitting the virus through breastfeeding
than mothers who have other children.
- In the new study, published in the August 25th issue
of The Journal of the American Medical Association, researchers led by
Dr. Paolo Miotti (affiliated with Johns Hopkins University, Baltimore,
at the time of the study) examined the HIV status of nearly 700 infants
born to HIV-positive women living in Malawi, a developing nation in southern
Africa. All of the infants were HIV-negative at time of birth.
- While they observed that the cumulative infection rate
increased over time, incidence of HIV infection was higher during the first
5 months of life. "Incidence per month was 0.7% during age 1 to 5
months, 0.6% during age 6 to 11 months, and 0.3% during age 12 to 17 months,''
- According to the investigators, their study suggests
that ''(the average) uninfected infant breastfed by an HIV-positive mother
for 23 months had at least a 10.3% risk of becoming infected.'' Risks appeared
to be highest "in the first half-year of life, when breastfeeding
is particularly important,'' they add.
- "Early weaning has been proposed as one possible
strategy to limit HIV transmission through breast milk,'' Miotti commented
in a press release. "Although discontinuing breastfeeding after 6
months would have prevented half of the HIV infections seen in our study,
such an approach would increase the risk for illness and death from the
respiratory and diarrheal diseases that antibodies and other factors in
breast milk help protect against.''
- In their report, Miotti's team also notes that women
who had four or more previous children and those who were older were less
likely to transmit HIV via breastfeeding than younger mothers or those
with fewer children. The finding supports a theory that "mothers who
are less experienced with breastfeeding are more likely to have (symptomless)
mastitis and thereby a higher HIV transmission rate,'' they write.
- The study findings "indicate that the incidence
of transmissibility is clearly greater during the early months of breastfeeding
than the later months,'' Dr. Anthony Fauci, director of the National Institute
of Allergy and Infectious Diseases (NIAID) in Bethesda, Maryland, told
- "The contribution of this study is that it gives
us a better handle on the timing of breastfeeding-transmitted HIV,'' Fauci
added. However, the findings do not "lead to an easy strategy.''
- For example, some people have suggested that weaning
babies as quickly as possible may reduce the risk, he explained. However,
this strategy was proposed with the assumption that the transmissibility
of HIV is constant throughout the breastfeeding period, Fauci explained.
Therefore, the new findings do not provide any easy prevention strategies
for HIV transmission through breastfeeding.
- Fauci added that the NIAID is now sponsoring trials to
investigate whether affordable, inexpensive drugs, or a single-dose of
a drug, such as nevirapine, administered to infants during the early phase
of breastfeeding, can decrease the incidence of this type of HIV transmission.
- The Joint United Nations Programme on HIV/AIDS currently
recommends that all HIV-positive mothers be informed of the pros and cons
of breastfeeding, and then be "supported in their choice'' by medical
- SOURCE: The Journal of the American Medical Association