New research suggests that babies whose mothers have HIV, but are not HIV-infected themselves, are born with lower levels of specific proteins in their blood called antibodies, which fight infection, compared with babies not exposed to HIV.
This study comes from scientists from Imperial College London and Stellenbosch University in South Africa and explains in part why uninfected babies born to women with HIV have a higher risk of illness and death early in life.
These babies are born with less resistance to a range of bacterial infections (including Hib or meningitis – brain fever, pertussis or whooping cough, pneumococcus – pneumonia and ear infections and tetanus). On the good note these babies responded well to vaccination: they produced similar levels of antibody to some vaccines and higher levels to other vaccines.
The study included 109 HIV-infected and uninfected mothers in a community health centre in Khayelitsha, a rapidly-growing township in Cape Town, South Africa. Results showed that 17 percent had antibody levels thought to protect against Haemophilus influenza type B, or HiB, compared with 52 percent of infants without exposure. Twenty-one percent of those exposed had antibodies against hepatitis B compared with 54 percent of unexposed babies. The results were reported today in the Journal of the American Medical Association and the study was led by Christine Jones a clinical research fellow in pediatrics at Imperial College London.
“Once the HIV-exposed, uninfected babies received their routine vaccinations, they had antibody levels similar to, or higher than, HIV unexposed infants, meaning that they were likely to be well protected by vaccination,” Jones said.
According to Michael Brady, chairman of the Department of Pediatrics at National Children’s Hospital in Columbus, Ohio, an independent observer, the study confirms what doctors had already thought. He said, “Maybe we should start developing a vaccine program for HIV-infected women to make sure that infants have the best opportunities to get mom’s antibodies at high levels.”
Researchers suggest that more studies are necessary to establish whether babies exposed prenatally to HIV could be better protected against infections through earlier vaccination, or through vaccine shots given to mothers before the children are born.
Makers of vaccines include New York-based Pfizer Inc., Paris-based Sanofi-Aventis SA, London-based GlaxoSmithKline Plc and Punjab, India-based Panacea Biotec Ltd.
Bruce Hirsch, an attending physician at North Shore University Hospital in Manhasset, New York, said while vaccinations may help, the priority should be getting women’s HIV under control. “They need to get their HIV under control as much as possible to decrease the frequency of transmitting HIV to their babies and to improve their own health and improve their own immune power,” Hirsch said.
The study was funded by the European Society for Pediatric Infectious Diseases, the Thrasher Research Foundation, the Wellcome Trust,the National Institute for Health Research, England, and the Elizabeth Glaser Pediatric AIDS Foundation.