Aids vaccine hope as HIV children 'tolerate' infection

LIZ HUNT

Health Editor

Almost three per cent of babies born HIV-positive will subsequently "clear" or "tolerate" the virus in later childhood and may be declared virus free, according to a study which will help vaccine development against Aids.

The study follows several reports from around the world of children born to HIV-positive mothers, who were found to be infected at birth, but who then appeared to rid their bodies of the virus in childhood.

Nine children out of 264 in the on-going European Collaborative Study of mothers and children, tested positive at or around birth and then negative for HIV at a later date. There was no HIV in the blood of seven of the children and they remained healthy.

Two other children tested antibody negative but the virus could still be detected in their blood using more sophisticated tests. However, they too remained well and doctors believe their immune systems could have "contained" the virus, and developed a tolerance to it so they no longer produced antibodies.

Writing in tomorrow's issue of The Lancet, Dr Marie-Louise Newall and her team from the Institute of Child Health in London, say: "If we could understand how virus-positive children subsequently become uninfected, we might gain insight into the mechanism of virus clearance. These mechanisms may have implications for vaccine development . . . it is important to continue the clinical and virological monitoring of these children. Current paediatric opinion is to inform parents of these children that their child is not infected with HIV."

The British Medical Journal also reports that British doctors have further strong evidence for HIV as a cause of Aids, refuting claims by a handful of scientists that it is a harmless passenger virus in the human body.

They found that a group of HIV-infected haemophiliac men developed Aids- related illnesses and had extensive damage to their immune systems while HIV-negative haemophiliacs did not.

The findings reject the view of some scientists, lead by Dr Peter Duesberg, an eminent American researcher, who argue that factors other than HIV, such as long-term illegal drug use or promiscuity, are responsible for Aids.

Dr Duesberg's explanation for the high incidence of Aids among haemophiliacs, which received worldwide attention after extensive publicity in the Sunday Times, is not that they received blood products contaminated with HIV, but that factor 8, the essential clotting agent needed by these patients, is itself a cause of the disease.

But a team from the Royal Free Hospital in north-west London which studied 17 HIV-positive and 17-HIV negative male haemophiliacs, who had all received similar, large quantities of factor 8 over time, found that the infected group suffered from Aids-related illnesses, such as pneumonia, thrush infections, cytomegalovirus, while the uninfected group failed to develop any of these. The HIV-positive group also had substantially lower white blood cell counts.