21 MARCH 1987, Page 20


Michael Trend describes the

risks which homosexuals and heterosexuals share

`LIFE itself is dangerous.' But how much more so since the advent of Aids? On 9 March the Health Department announced the latest in its series of monthly figures. Of a total of 731 people who have so far devleoped the disease in the United King- dom 640 are homosexual. Of the others, those who contracted Aids through in- fected blood transfusions are the next highest category, then there are 25 cases of heterosexuals with the disease, of whom ony five are believed to have contracted it through heterosexual activity in the United Kingdom. Drug abusers and babies born to infected mothers (seven so far) make up the rest of the total.

The Government's response to the spread of this virus has been cautious; after much consideration it sent out to every household in the land a pamphlet, which, if its distribution has been as successful as hoped, everyone will have had an oppor- tunity to read. There has also been an unprecedented public health campaign, which included the slogan 'Aids is not prejudiced'. But on learning the figures quoted above, this slogan seems nonsensic- al to many people. How can a disease that is supposedly unprejudiced pick out so many homosexuals?

The answer comes from the study of the transmission of viral diseases; and in the understanding of the transmission of Aids lies the key to a greater public understand- ing of the disease. Anyone who partakes in sexual activity with a number of partners obviously has a greater chance, statistically speaking, of contracting a sexually trans- mitted disease, but over and above this, male homosexuals have, in a sense, parti- cularly selected themselves due to the nature of their sexual activity. The trans- mission of blood-borne viruses requires above all a 'portal', an entry point for the virus to get into the bloodstream of the person who is to contract the disease. Male homosexual anal intercourse, which often involves internal lesions, and therefore opens up such a portal into the recipient, is an especially effective way of transmitting viruses of this kind. Such was the case with Hepatitis B, another blood-borne virus which in recent years has been a major killer. This also has been especially preva- lent amongst homosexuals.

But what of the other groups in the Government's figures? Those who have contracted Aids through infected blood haemophiliacs and those who have re- ceived infected blood transfusions — have been monstrously unlucky: the portal through which it entered their blood- streams was not of their own choice 'or making. Steps have now been taken to protect these groups of people as far as possible, although many feel that these were far too slow. There is, too, the possibility of contracting the disease through infected blood abroad. Eight of the 12 reported cases in this category are believed to have been contracted overseas. One is lost for words when thinking of the seven babies in the womb who have contracted the disease (four of which have so far died).

Drug abusers, like homosexuals, may well have in some very restricted sense `chosen' to make a portal into themselves through which the disease might be trans- mitted. This has been a particularly severe problem in Scotland where the virus spread rapidly among drug-takers in Glasgow and Edinburgh who shared needles and syring- es. It was suggested that the Scottish police could help the situation by not confiscating drug abusers' equipment when they arrested them. This is difficult ground.

The main area of contention, however, is about the cases of Aids — the vast majority — that have been contracted sexually. As we have seen, of the 731 cases reported only five are believed to have contracted it through heterosexual sexual activity in the United Kingdom. The ways in which the virus might have been trans- mitted in these cases include those where the virus passes from the blood of an infected person into the other body fluids and from these, through a portal — say, a scratch in the vaginal wall or on the penis — into a heterosexual partner. But one must also consider the possibility of infec- tion through contact with partners already in high-risk groups. The virus can also be found in minuscule amounts of saliva and tears, but there are no reported cases from anywhere in the world of it having been transmitted in this way. So are heterosexuals at any serious risk in a statistical sense? Here there are divided opinions although all agree that the risk to heterosexuals is far, far less than that to homosexual males. The figures that we are reading now — like the stars we see in the heavens — reflect an historical picture. People reported as having Aids today will have contracted the virus about five years ago. It may well prove to be the case that five years ago the virus was almost entirely transmitted by homosex- uals to each other. But at some stage it will have passed to heterosexuals — via bisex- uals, drug abusers and transfusions — and, once established, can be transmitted in the ways described. The incidence of transmis- sion will depend on the same factor as affected homosexual activity — the pre- sence of a portal. This is much less likely to be the case in heterosexual activity. Fi- gures in the United States, which is histor- ically in advance of the United Kingdom, do show a modest increase in the number of heterosexual cases in recent years.

How many of these cases were the result of conventional heterosexual intercourse is a question about which considerable doubt still exists. Recently collated figures below, from the Department of Genito-urinary Medicine at St Thomas's Hospital in Lon- don, show the number of tests on walk-in patients who described themselves as not belonging to any of the recognised risk groups — ie partners of homosexuals, bisexuals and drug abusers. There is also a separate figure for those categorised as `promiscuous heterosexuals' — people with more than two sexual contacts in the preceding two months.

Quarter patients tested Jan-March 1986 20 April-June 40 July-Sept 48 Oct-Dec 180 Jan-20 Feb 1987 308 Promiscuous Heterosexuals 83


679 There were no positive results in any of these tests.

But researchers stress that this does not mean that Aids has not passed through heterosexual contact and will not continue to do so. As a virus, it has no inbuilt predisposition to any particular group of individuals. Its 'choices' depend on how far individuals facilitate its transmission. The Government's public health campaign spreading knowledge and fear of the dis- ease as widely as possible — may well be seen in the future as having been the most sensible starting point. We cannot yet judge its success in medical terms; the results will only begin to show in the next five years. As to the wider political issues raised by Aids, that is another question. Number of