improve the situation. We have instituted a system of laboratory reporting directly to the consultant in communicable disease control and have not encountered any problems recognising duplicate reports. In the meantime there needs to be greater awareness among doctors of the need and legal requirement for notification of infectious diseases. RUTH WHITE JOHN CHEESBROUGH DILIP ZALA Department of Medical Microbiology and Genitourinary Medicine, Royal Liverpool University Hospital, Liverpool L69 3BX 1 Tilzey AJ, Banatvala JE. Hepatitis A. BMJ 1991;302:1552-3. (29 June.) 2 Regan CM, Syed Q, Corkery A. Hepatitis A vaccine. BMJ 1991;303:414. (17 August.) 3 Harvey IM, Peters TJ, Palmer SR. Meningitis: can we trust the statistics? Health Trends 1989;21:73-6. 4 Department of Health. Review of law on infectious disease control-consultation document. London: DoH, 1989.
Hepatitis C virus
CRESIO PEREIRA CHRISTINE A LEE GEOFFREY DUSHEIKO
Haemophilia Centre and Haemostasis Unit, Royal Free Hospital and School of Medicine, London NW3 2QG 1 Fagan EA. Testing for hepatitis C virus. BMJ 1991;303:535-6.
(7 September.)
Sexual transmission of hepatitis C virus SIR,-Epidemiological evidence shows that sexual contact is a risk factor for acute non-A non-B hepatitis. ' Dr R S Tedder and colleagues found some evidence for the sexual transmission of hepatitis C virus infections among British patients attending a genitourinary clinic.2 The findings were confirmed by Riestra and Carcaba with data from Spain, who also showed a significant relation between the presence of antibody to hepatitis C virus in homosexual men and a history of intravenous drug addiction.3 Riestra and Carcaba concluded that in some populations a raised prevalence of antibody to hepatitis C virus may be explained by parenteral mechanisms. We determined the prevalence of antibody to 303
Prevalence of antibody to hepatitis C virus in patients with sexually transmitted diseases
Age
SIR,-Dr Elizabeth Ann Fagan suggests that the reluctance in the United Kingdom to begin widespread testing of blood donors for hepatitis C virus before the introduction of second generation antibody tests seems justified.' This may be the view from the perspective of a calculated loss of 10000 blood units a year. This has to be balanced, however, against the threat of transmission of hepatitis C virus, and the attendant risk of chronic hepatitis, to around 1500 recipients a year who received unscreened blood. This includes patients with bleeding disorders. Our only haemophiliac child who is positive for antibody to hepatitis C virus (first and second generation tests) received whole blood at presentation at the age of 10 months in February 1990. This child has never received clotting factor concentrate and now has a consistently abnormal aspartate transaminase activity. In contrast, all 20 children aged 10 years and under (median 4 years 6 months, range 1 year 9 months to 10 years) who have received only heat sterilised factor VIII or IX concentrate manufactured by either Bio-Products Laboratory or Alpha (UK) Ltd (total 1113575 units (range per child 1730-214105 units) over 49- S patient years (range six months to five years)) are negative for antibody to hepatitis C virus.
BMJ
hepatitis C virus in 487 Belgian patients attending a clinic for sexually transmitted diseases. The overall prevalence was 0-82%, which is considerably higher than that of 0-33% found in 301 blood donors from the same region.4 Because of the small number of patients positive for antibody in both groups the results were not significantly different (p>005). It should be noted here that Desmyter et al found the prevalence of antibody to hepatitis C virus in blood donors in Belgium to be 0 55%, but these data resulted from a study using the first commercial screening test for these antibodies (Ortho) without any confirmatory test.s We used the second generation test from Abbott and confirmed all positive results with a neutralisation test (Abbott). The table summarises the prevalence of hepatitis C virus antibody as a function of age and sex.
28
SEPTEMBER
1991
Men (mean age 34)
(mean age 31)
Women
Total (mean age 33)
No of No (%)
No of No (%)
No of No (%)
(years) patients positive patients positive patients positive 11 130 97 77
1(9 09) 2 (1-54)
12 88 39 33
1(1-14)
23 218 136 110
1(4-35) 3 (1-38)
30-40 >40 Total
315
3 (0-95)
172
1 (058)
487
4 (0-82)
620 20-30
The prevalence of antibody to HIV and hepatitis B virus markers were also determined in these patients. The prevalence of HIV antibody was 4-17% (5-23% in men and 2 26% in women), significantly higher (p0-001) than the 1-0% found in Belgian blood donors.7 Of the four patients positive for hepatitis C virus antibody, two were also positive for hepatitis B c antibody; the other two tested negative for hepatitis B virus markers. These data lead us to conclude that in Belgium hepatitis C virus infections are far less important as sexually transmitted diseases than HIV and hepatitis B virus infections. ROBERT VRANCKX
Institute of Hygiene and Epideniiology, 1050 Brussels,
Belgium 1 Alter MJ, Coleman PJ, Alexander WJ, Kramer E, Miller JK, Mandel E, et al. Importance of heterosexual activity in the transmission of hepatitis B and non-A, non-B hepatitis. JAMA 1989;262: 1202-5. 2 Tedder RS, Gilson RJC, Briggs M, Loveday C, Cameron CH, Garson JA, et al. Hepatitis C virus: evidence for sexual transenision. BMJ 1991;302:1299-302. (1 June.) 3 Riestra S, Carcaba V. Hepatitis C virus: evidence for sexual transmission. BMJ 1991;303:310-1. (27 July.) 4 Vranckx R, Muylle L. HAV infections in Belgium. Proceedings of the second international conference on travel medicine, Atlanta 1991 (in press). 5 Desmyter J, Goubau P, Vermylen C, Sondag-Thull D. Ortho anti-HCV clinical trial in Belgium: selected results. Viral hepatitis C, D and E. In: Shikata T, Purcell RH, Uchida T, eds. Proceedings of the international meeting on non-A, non-B hepatitis, Tokyo, 27-30 September 1989. Amsterdam: Excerpta Medica, 1991. 6 Haemophilia Study Group. Haemophilia, HIV infection, and blood transfusion in Belgium. Acta Clin Belgica 1988;43: 95-100. 7 Vranckx R, Cole J, Peetermans M. The prevalence of ay and ad subtypes of the hepatitis B surface antigen in Belgium. Infection 1978;6:2-4.
Sexual behaviour in Scottish prisons SIR,-Two letters' 2 were recently published referring to the article by our research group that dealt with high risk sexual behaviour in Scottish prisons.3
A number of issues in these letters require a response. Dr K Mair notes that during the past year three male inmates admitted to her that they "participate in sex." She does not state the size of the sample from which these three inmates were drawn, and therefore readers are unable to judge the prevalence of such behaviour. Dr Mair's address is given as HM Prison Invernettie, Peterhead. No such prison exists. If her data relate to HM Prison Peterhead then it seems pertinent to point out that during the period in which she collected her data the population of the prison comprised 100 sex offenders, 18 non-sex offenders, and 14 disruptive or difficult prisoners. This sample is not representative of the Scottish prison population. We were specifically concerned with high risk penetrative sexual behaviour. Unfortunately, many of the anecdotal reports of sexual behaviour among inmates fail to make the crucial distinction between high and low risk sexual behaviour. Dr Mair fails to describe the particular sexual behaviour with regard to the relative risk of HIV transmission. Dr Mair claims that it is unlikely that inmates would disclose information about their sexual behaviour during incarceration at first interview but would be more likely to do so at subsequent interviews. Since she does not provide more information to substantiate this claim, her point
remains speculative. Dr Mair suggests that male inmates are unlikely to admit to homosexuality because it is "strongly disapproved of." This of course is the most obvious criticism of any research based on interviews, but evidence is needed to corroborate such a suggestion. Dr A Bartlett also raised several points that need to be addressed. Dr Bartlett quotes widely from American reports concerning sexual activity in prisons, but we do not consider it scientifically sound to make generalisations from data collected in a country with a different culture and prison regime from those operating in Scotland. As Dr Bartlett emphasises the benefits of an anthropological approach in research she will surely appreciate this particular point. Dr Bartlett claims that our results are unreliable, but she fails to substantiate this claim. Finally, she suggests that "systematic participation and observation over time" would be a better method of study. We find it difficult to imagine how this could be put into practice, or that it would be accepted by inmates, in an investigation of high risk anal intercourse in prison settings. K G POWER I MARKOVA A ROWLANDS
Department of Psychology, University of Stirling, Stirling FK9 4LA 1 Mair KJ. Sexual behaviour in Scottish prisons. BMJ 1991;303: 364. (10 August.) 2 Bartlett A. Sexual behaviour in Scottish prisons. BMJ 1991;303: 364. (10 August.)
3 Power KG, Markovi I, Rowlands A, McKee KJ, Anslow PJ, Kilfedder C. Sexual behaviour in Scottish prisons. BMJ 1991;302:1507-8. (22 June.)
Zidovudine after exposure to HIV SIR,-While the medical profession agonises over the use of zidovudine after occupational exposure to HIV'2 a more important issue perhaps is the use of the drug after sexual exposure. Those working with HIV positive people emphasise that many such people continue to have active sex lives and practise safe sex regularly and happily. If under these circumstances a condom breaks should the uninfected, recipient partner be offered zidovudine? Published reports offer no help in this 783
Hepatitis C virus
CRESIO PEREIRA CHRISTINE A LEE GEOFFREY DUSHEIKO
Haemophilia Centre and Haemostasis Unit, Royal Free Hospital and School of Medicine, London NW3 2QG 1 Fagan EA. Testing for hepatitis C virus. BMJ 1991;303:535-6.
(7 September.)
Sexual transmission of hepatitis C virus SIR,-Epidemiological evidence shows that sexual contact is a risk factor for acute non-A non-B hepatitis. ' Dr R S Tedder and colleagues found some evidence for the sexual transmission of hepatitis C virus infections among British patients attending a genitourinary clinic.2 The findings were confirmed by Riestra and Carcaba with data from Spain, who also showed a significant relation between the presence of antibody to hepatitis C virus in homosexual men and a history of intravenous drug addiction.3 Riestra and Carcaba concluded that in some populations a raised prevalence of antibody to hepatitis C virus may be explained by parenteral mechanisms. We determined the prevalence of antibody to 303
Prevalence of antibody to hepatitis C virus in patients with sexually transmitted diseases
Age
SIR,-Dr Elizabeth Ann Fagan suggests that the reluctance in the United Kingdom to begin widespread testing of blood donors for hepatitis C virus before the introduction of second generation antibody tests seems justified.' This may be the view from the perspective of a calculated loss of 10000 blood units a year. This has to be balanced, however, against the threat of transmission of hepatitis C virus, and the attendant risk of chronic hepatitis, to around 1500 recipients a year who received unscreened blood. This includes patients with bleeding disorders. Our only haemophiliac child who is positive for antibody to hepatitis C virus (first and second generation tests) received whole blood at presentation at the age of 10 months in February 1990. This child has never received clotting factor concentrate and now has a consistently abnormal aspartate transaminase activity. In contrast, all 20 children aged 10 years and under (median 4 years 6 months, range 1 year 9 months to 10 years) who have received only heat sterilised factor VIII or IX concentrate manufactured by either Bio-Products Laboratory or Alpha (UK) Ltd (total 1113575 units (range per child 1730-214105 units) over 49- S patient years (range six months to five years)) are negative for antibody to hepatitis C virus.
BMJ
hepatitis C virus in 487 Belgian patients attending a clinic for sexually transmitted diseases. The overall prevalence was 0-82%, which is considerably higher than that of 0-33% found in 301 blood donors from the same region.4 Because of the small number of patients positive for antibody in both groups the results were not significantly different (p>005). It should be noted here that Desmyter et al found the prevalence of antibody to hepatitis C virus in blood donors in Belgium to be 0 55%, but these data resulted from a study using the first commercial screening test for these antibodies (Ortho) without any confirmatory test.s We used the second generation test from Abbott and confirmed all positive results with a neutralisation test (Abbott). The table summarises the prevalence of hepatitis C virus antibody as a function of age and sex.
28
SEPTEMBER
1991
Men (mean age 34)
(mean age 31)
Women
Total (mean age 33)
No of No (%)
No of No (%)
No of No (%)
(years) patients positive patients positive patients positive 11 130 97 77
1(9 09) 2 (1-54)
12 88 39 33
1(1-14)
23 218 136 110
1(4-35) 3 (1-38)
30-40 >40 Total
315
3 (0-95)
172
1 (058)
487
4 (0-82)
620 20-30
The prevalence of antibody to HIV and hepatitis B virus markers were also determined in these patients. The prevalence of HIV antibody was 4-17% (5-23% in men and 2 26% in women), significantly higher (p0-001) than the 1-0% found in Belgian blood donors.7 Of the four patients positive for hepatitis C virus antibody, two were also positive for hepatitis B c antibody; the other two tested negative for hepatitis B virus markers. These data lead us to conclude that in Belgium hepatitis C virus infections are far less important as sexually transmitted diseases than HIV and hepatitis B virus infections. ROBERT VRANCKX
Institute of Hygiene and Epideniiology, 1050 Brussels,
Belgium 1 Alter MJ, Coleman PJ, Alexander WJ, Kramer E, Miller JK, Mandel E, et al. Importance of heterosexual activity in the transmission of hepatitis B and non-A, non-B hepatitis. JAMA 1989;262: 1202-5. 2 Tedder RS, Gilson RJC, Briggs M, Loveday C, Cameron CH, Garson JA, et al. Hepatitis C virus: evidence for sexual transenision. BMJ 1991;302:1299-302. (1 June.) 3 Riestra S, Carcaba V. Hepatitis C virus: evidence for sexual transmission. BMJ 1991;303:310-1. (27 July.) 4 Vranckx R, Muylle L. HAV infections in Belgium. Proceedings of the second international conference on travel medicine, Atlanta 1991 (in press). 5 Desmyter J, Goubau P, Vermylen C, Sondag-Thull D. Ortho anti-HCV clinical trial in Belgium: selected results. Viral hepatitis C, D and E. In: Shikata T, Purcell RH, Uchida T, eds. Proceedings of the international meeting on non-A, non-B hepatitis, Tokyo, 27-30 September 1989. Amsterdam: Excerpta Medica, 1991. 6 Haemophilia Study Group. Haemophilia, HIV infection, and blood transfusion in Belgium. Acta Clin Belgica 1988;43: 95-100. 7 Vranckx R, Cole J, Peetermans M. The prevalence of ay and ad subtypes of the hepatitis B surface antigen in Belgium. Infection 1978;6:2-4.
Sexual behaviour in Scottish prisons SIR,-Two letters' 2 were recently published referring to the article by our research group that dealt with high risk sexual behaviour in Scottish prisons.3
A number of issues in these letters require a response. Dr K Mair notes that during the past year three male inmates admitted to her that they "participate in sex." She does not state the size of the sample from which these three inmates were drawn, and therefore readers are unable to judge the prevalence of such behaviour. Dr Mair's address is given as HM Prison Invernettie, Peterhead. No such prison exists. If her data relate to HM Prison Peterhead then it seems pertinent to point out that during the period in which she collected her data the population of the prison comprised 100 sex offenders, 18 non-sex offenders, and 14 disruptive or difficult prisoners. This sample is not representative of the Scottish prison population. We were specifically concerned with high risk penetrative sexual behaviour. Unfortunately, many of the anecdotal reports of sexual behaviour among inmates fail to make the crucial distinction between high and low risk sexual behaviour. Dr Mair fails to describe the particular sexual behaviour with regard to the relative risk of HIV transmission. Dr Mair claims that it is unlikely that inmates would disclose information about their sexual behaviour during incarceration at first interview but would be more likely to do so at subsequent interviews. Since she does not provide more information to substantiate this claim, her point
remains speculative. Dr Mair suggests that male inmates are unlikely to admit to homosexuality because it is "strongly disapproved of." This of course is the most obvious criticism of any research based on interviews, but evidence is needed to corroborate such a suggestion. Dr A Bartlett also raised several points that need to be addressed. Dr Bartlett quotes widely from American reports concerning sexual activity in prisons, but we do not consider it scientifically sound to make generalisations from data collected in a country with a different culture and prison regime from those operating in Scotland. As Dr Bartlett emphasises the benefits of an anthropological approach in research she will surely appreciate this particular point. Dr Bartlett claims that our results are unreliable, but she fails to substantiate this claim. Finally, she suggests that "systematic participation and observation over time" would be a better method of study. We find it difficult to imagine how this could be put into practice, or that it would be accepted by inmates, in an investigation of high risk anal intercourse in prison settings. K G POWER I MARKOVA A ROWLANDS
Department of Psychology, University of Stirling, Stirling FK9 4LA 1 Mair KJ. Sexual behaviour in Scottish prisons. BMJ 1991;303: 364. (10 August.) 2 Bartlett A. Sexual behaviour in Scottish prisons. BMJ 1991;303: 364. (10 August.)
3 Power KG, Markovi I, Rowlands A, McKee KJ, Anslow PJ, Kilfedder C. Sexual behaviour in Scottish prisons. BMJ 1991;302:1507-8. (22 June.)
Zidovudine after exposure to HIV SIR,-While the medical profession agonises over the use of zidovudine after occupational exposure to HIV'2 a more important issue perhaps is the use of the drug after sexual exposure. Those working with HIV positive people emphasise that many such people continue to have active sex lives and practise safe sex regularly and happily. If under these circumstances a condom breaks should the uninfected, recipient partner be offered zidovudine? Published reports offer no help in this 783
