SUNDAY, Jan. 18 (HealthDay News) -- The antiretroviral drug nevirapine may help prevent babies of HIV-positive mothers from getting the virus through breast-feeding, but it also greatly increases the odds of developing drug-resistant HIV if they are infected during the first year of life, a new study finds.

Still, the researchers consider the six-week course of the drug the best alternative available.

Given the higher chance of a baby on nevirapine acquiring treatment-resistant HIV, the authors call for the infants to also receive protease inhibitors (PIs), which can combat nevirapine-resistant HIV strains.

"Until other interventions become available, the extended nevirapine regimen remains a reasonable way to prevent infections through breast-feeding," senior investigator Dr. Deborah Persaud, a pediatric HIV expert at John Hopkins Children's Center, said in a news release issued by the school.

The study, published in the Jan. 1 issue of the Public Library of Science One, noted the treatment is best for HIV-positive mothers in developing countries where bottle feeding is not an alternative because of cost, safety or availability.

HIV infection is estimated to occur in one out of 10 breast-fed infants, most of the time happening in the first 14 weeks of life, according to estimates by the World Health Organization (WHO), which recommends breast-feeding for at least six months despite the known risk of HIV transmission.

Two reports published in 2008 found that a six-week treatment of nevirapine cut the risk of HIV infection from breast-feeding nearly in half, while a 14-week regimen cut it by 66 percent.

Related MedlinePlus Pages:

• AIDS and Pregnancy
• AIDS Medicines