Letter: Tuberculosis and the spread of Aids

Sir: It is timely that William Rees- Mogg ('A tragedy far beyond human understanding', 10 August) has highlighted the plight of Africa and, in particular, drawn attention to the tragic consequences of the interaction between one of the oldest plagues of mankind, tuberculosis, and the most recent, HIV infection.

Worldwide, at least four million people are dually infected with HIV and the tubercle bacillus, and three-quarters of these live in Africa. Indeed, in some areas of Africa up to 80 per cent of patients with tuberculosis are HIV positive. There are three very serious consequences of this dual

infection.

First, dually infected people are 10 times more likely to develop overt tuberculosis than those infected with the tubercle bacillus alone. As a consequence, the incidence of tuberculosis has doubled in many African countries over the past 10 years, swamping the already heavily stretched health services.

Second, tuberculosis is one of the few HIV-related diseases that can be transmitted to other members of the community, both HIV positive and negative.

Third, and perhaps most worrying, there is strong evidence that both infections lead to a destruction of those cells (the T cells) that induce protective responses and that tuberculosis occurring in HIV-positive persons may plunge them into full-blown Aids.

Is the answer to the tragedy of HIV-related tuberculosis beyond human understanding? In an article entitled 'Is Africa Lost?' published in the Lancet (31 August), we made the optimistic assertion that it is not.

Our studies on the use of immunotherapy lead us to conclude that we can combat the ability of the HIV and the tubercle bacillus to force the human immune system into submission.

Your cartoon of 11 August depicts the obscenity of the unnecessary deaths in Africa. The true obscenity is the failure of health services to utilise the potent therapeutic armaments now available to prolong and save life.

Yours faithfully,

JOHN GRANGE

Royal Brompton Hospital

JOHN STANFORD

Middlesex Hospital

ANTON POZNIAK

King's Hospital

London, SW3

12 August