Prevalence of HIV-1 infection among heterosexual men and women attending genitourinary clinics in Scotland: unlinked anonymous testingBMJ 1997; 315 doi: https://doi.org/10.1136/bmj.315.7118.1281 (Published 15 November 1997) Cite this as: BMJ 1997;315:1281
- G Scott, consultant physiciana,
- D Goldberg (), deputy directorb,
- M Weir, consultant physicianc,
- S Cameron, top grade scientistd,
- J Peutherer, senior lecturere,
- D Carrington, consultant virologistf,
- E Follett, consultant virologistd,
- G Leadbetter, chief medical laboratory scientific officere,
- A Scoular, consultant physiciang
- a Department of Genitourinary Medicine, Royal Infirmary, Edinburgh EH3 9YW
- b Scottish Centre for Infection and Environmental Health, Ruchill Hospital, Glasgow G20 9NB
- c Department of Genitourinary Medicine, Royal Free Hospital, London NW3 2QG
- d Regional Virus Laboratory, Ruchill Hospital, Glasgow G20 9NB
- e Department of Microbiology, University of Edinburgh, Edinburgh EH8 9AG
- f Department of Virology, St George's Hospital Medical School, London SW17 0RE
- g Department of Genitourinary Medicine, Royal Infirmary, Glasgow G4 0SF
- Correspondence to: Dr Goldberg
- Accepted 28 May 1997
In late 1990 a survey of unlinked anonymous HIV testing of patients attending genitourinary clinics in Glasgow and Edinburgh was implemented to monitor the prevalence of HIV-1 infection among sentinel populations at high risk of infection. These clinics served 90% and 100% of their respective city populations. We report on the prevalence of HIV infection among heterosexual men and women who were not known to have injected drugs and who attended clinics in Edinburgh and Glasgow from 1991 to 1995.
Subjects, methods, and results
Each clinic routinely performed serology testing for syphilis on patients who might have acquired a sexually transmitted disease. Patients eligible for study included those who presented for the first time in a calendar quarter and who did not object to their blood undergoing unlinked anonymous testing for HIV. Epidemiological data were recorded and included clinic of attendance, sexual orientation, sex, whether the patient had ever injected drugs, and limited geographical characteristics which applied to lifetime HIV risk; information was collected on location of risk, nationality of sexual contact, and nationality of patient according to the categories United Kingdom, Europe, Africa, Asia, Americas, and Oceania. The process of anonymising specimens, testing them for HIV, and ascribing limited risk factor information to the results has been described previously.1 Specimens were also categorised by their geographical characteristics into three groups of increasing risk—United Kingdom, other, and Africa—specimens from people declaring any nationality or location associations with Africa being classed as Africa.
Between January 1991 and December 1995, 40 146 specimens from heterosexual attenders were tested anonymously for HIV. In addition, 46 (0.11%) attenders objected to their blood being tested for HIV and 7392 (15.5%) were not tested for other reasons, including difficulties in gaining venous access. Of the 99 seropositive specimens from patients recorded as heterosexual, 57 were classed geographically as the United Kingdom alone, 22 as Africa, and 20 as other. The overall infection hazard between 1991 and 1995 was similar for men in both cities but greater for women in Edinburgh (1). When cases were grouped by geographical connection, highly significant differences in risk were apparent in both men and women; among people with British connections alone, those in Glasgow had a lower risk than those in Edinburgh, while all those with an African connection had the greatest risk. In Glasgow alone, those with other geographical associations had a slightly greater risk than those with only a British connection.
The prevalence of HIV infection in men and women with only a British connection was about 0.3% in Edinburgh compared with less than 0.1% in Glasgow. These observations probably reflected the impact of HIV epidemics among injecting drug users on the spread of infection to non-injecting heterosexual men and women; prevalence among injecting drug users in Glasgow never exceeded 2% while in Edinburgh it varied between 20% and 51%.2
In central Scotland, however, heterosexual men and women with an African connection had the greatest risk of being HIV positive. Similar or even more pronounced observations might be expected elsewhere in the United Kingdom. Indirect evidence suggests that most pregnant women who are HIV positive in London originate from Africa, but zidovudine, which can reduce the risk of vertical transmission, cannot be given to many of them because their infections remain undetected.3 Recent investigations suggested that HIV subtype E, prevalent in Asia and Africa, may have greater transmissibility than subtype B, which predominates in Europe.4
As recommended by the health departments of the United Kingdom, measures should be taken to improve awareness of HIV and its prevention among travellers, especially people travelling to countries where HIV transmission is common.5
We thank the following for their help: J D Dickson and N Scott (Department of Medical Microbiology, University Medical School, Edinburgh); S Sommerville (Department of Genitourinary Medicine, Royal Infirmary, Edinburgh); E McEwan, L McWhirter, M Miller, M Knox, J Roberts, and S Wyper (Department of Genitourinary Medicine, Royal Infirmary, Glasgow); J Winning (Department of Bacteriology, Southern General Hospital, Glasgow); G Allardice, E Carragher, G Codere, S Donald, J Emslie (retired), L Linden, D Reynolds, W Smyth, and J Tolland (Scottish Centre for Infection and Environmental Health); E Campbell, G Clements, R McHugh, L McDonald, and K Wilson (Regional Virus Laboratory, Ruchill Hospital, Glasgow). We also thank Dr Angus Nicoll at the Communicable Disease Surveillance Centre for his helpful comments.
Conflict of interest: None.
Funding: Medical Research Council's Committee on the Epidemiological Study of AIDS, and Scottish Department of Health.