SUMMARY: Only about half of babies born to HIV positive mothers in 4 African countries received at least a minimum preventive dose of nevirapine (Viramune) immediately after birth to reduce the risk of mother-to-child transmission, according to a study in the July 21, 2010 Journal of the American Medical Association, a special HIV/AIDS issue coinciding with the XVIII International AIDS Conference (AIDS 2010) last month in Vienna. The World Health Organization (WHO) has released new guidelines recommending that all women with HIV should receive antiretroviral drugs to protect against HIV transmission during pregnancy, delivery, or breastfeeding, and that diagnostic testing should be expanded for infants to enable those infected to receive prompt treatment.

Maternal use of antiretroviral drugs during pregnancy, delivery, and breast-feeding, and treatment of infants soon after birth, is proven effective in preventing mother-to-child HIV transmission. Nevertheless, according to WHO, approximately 400,000 infants each year still acquire HIV via vertical transmission.

Elizabeth Stringer from the Centre for Infectious Disease Research in Zambia and colleagues with the PEARL study team estimated the extent of coverage of existing services to prevent mother-to-child HIV transmission in Cameroon, Cote d'Ivoire, South Africa, and Zambia.

Between June 2007 and October 2008, they collected umbilical cord blood samples from 43 randomly selected facilities providing childbirth services. All sites used at least single-dose nevirapine to prevent mother-to-child transmission; some sites also used additional antiretroviral drugs for prophylaxis.

The researchers determined whether women took nevirapine by measuring drug levels in cord blood at the time of delivery, and directly observed whether infants received the recommended dose after birth.

Results

	Out of 27,893 tested cord blood specimens, 3324 (12%) were found to be HIV seropositive.
	Looking at 3196 seropositive mother-infant pairs who underwent cord blood nevirapine measurement:
	1845 mothers took nevirapine; 1725 HIV-exposed infants received total coverage (that is, both mother and baby received the drug).
	Total coverage rates varied substantially by country and by site within a country, however, ranging from 0% to 82%.
	In an adjusted analysis, the overall average level of coverage for the 4 countries was estimated to be 51%.
	Maternal non-adherence -- assumed based on absence of nevirapine in the cord blood from women who had the drug dispensed to them before delivery -- was common.
	Factors significantly associated with failure to achieve total nevirapine coverage included:
	Maternal age less than 20 years: adjusted odds ratio (aOR) 1.44 vs > 30 years; Maternal age between 20 and 25 years: aOR 1.28 vs > 30 years; None or only 1 prenatal care visit: aOR 2.91 vs > 6 visits; 2 or 3 prenatal care visits: aOR 1.93 vs > 6; 4 or 5 prenatal visits: aOR 1.56 vs > 6; Vaginal (as opposed to Cesarean) delivery: aOR 1.22; Low infant birth weight (< 2500 g): aOR 1.34 vs > 3500 g.

These findings led the study authors to conclude, "In this random sampling of sites with services to prevent mother-to-child HIV transmission, only 51% of HIV-exposed infants received the minimal regimen of single-dose nevirapine."

The study also analyzed the path or "cascade" that mothers and infants must negotiate to prevent vertical HIV transmission, from being offered an HIV test during pregnancy, to dispensing nevirapine, to ensuring that both mother and baby take the drug as directed.

"Our findings indicate that programmatic failures are common along this path, and that each clinic faces its own mix of challenges in maximizing service coverage," the researchers wrote.

WHO Guidelines

In November 2009, WHO issued revised international guidelines recommending earlier antiretroviral therapy (ART) for HIV positive adults (starting at 350 rather than 200 cells/mm3), more extensive therapy during pregnancy, and continuation of treatment for mothers and/or babies during breast-feeding to prevent vertical HIV transmission.

The new guidelines released last month recommend that all women with HIV should receive antiretroviral drugs to protect against HIV transmission during pregnancy, delivery, or breast-feeding. WHO indicated that mothers may safely breast-feed provided that they or their infants receive antiretroviral drugs during the breast-feeding period.

"We know what to do," said Jimmy Kolker, UNICEF's Chief of HIV and AIDS. "Ending transmission of HIV from mothers to children is entirely achievable and must be a priority."

"Virtual elimination of mother to child transmission of HIV by 2015 is possible," UNAIDS Deputy Executive Director Paul De Lay added in a WHO press release. "Relatively small investments can go a long way in saving mothers and babies."

Turning to children that do become HIV-infected, WHO noted that 355,000 children were receiving life-saving ART at the end of 2009, compared with 276,000 at the end of 2008.

Until now, few babies under 1 year of age have started treatment, in part because the type of HIV testing needed for this group has not been available in many settings. WHO called for greater access to infant diagnosis starting at 4-6 weeks after birth.

Without diagnosis followed by prompt initiation of treatment, an estimated one-third of HIV-infected infants will die before their first birthday, and about half will die before reaching 2 years of age, according to the organization.

"With early diagnosis and prompt treatment, children have far better chances of surviving," said WHO Director of HIV/AIDS Gottfried Hirnschall.

Investigator Affiliations: Centre for Infectious Disease Research in Zambia, Lusaka, Zambia; Programme PAC-CI, Abidjan, Côte d'Ivoire; Infectious Diseases and Epidemiology Unit, School of Public Health and Community Medicine, University of Cape Town, Cape Town, South Africa; Cameroon Baptist Health Convention Health Board, Bamenda; Centers for Disease Control and Prevention, National Center for HIV/AIDS, Viral Hepatitis, STD, and TB Prevention, Global AIDS Program, Atlanta, GA; Elizabeth Glaser Pediatric AIDS Foundation, Santa Monica, CA; Department of HIV/AIDS, World Health Organization, Geneva, Switzerland; Institut de Santé Publique, Epidémiologie et Développement, Université Victor Segalen Bordeaux 2, Bordeaux, France.

8/6/10

Reference

EM Stringer, DK Ekouevi, D Coetzee, and others (PEARL Study Team). Coverage of nevirapine-based services to prevent mother-to-child HIV transmission in 4 African countries. Journal of the American Medical Association 304(3): 293-302 (Abstract). July 21, 2010.

Other sources

World Health Organization. WHO announces new approaches to HIV prevention and treatment among children. Press release. July 20, 2010.

JAMA and Archives Journals. Many HIV-exposed infants in African countries not receiving medication to help prevent HIV. Media advisory. July 18, 2010.