Initial suboptimal CD4 reconstitution with antiretroviral therapy despite full viral suppression in a cohort of HIV-infected patients in Senegal

OBJECTIVE

We determined the risk factors and incidence of clinical events associated with suboptimal immune reconstitution (SIR) defined by an increase in CD4 inferior to 50 cells/μL, from inclusion up to six months of antiretroviral treatment (ARVT), in patients with an undetectable viral load (<50 copies/mL).

METHODS

Logistic regression and Cox's proportional hazards model were used to examine risk factors for SIR and the association between SIR and the risk of new clinical events or death, respectively after six months of ARVT.

RESULTS

One hundred and two (15.5%) of the 657 patients presented with SIR. Age > 40 years (aOR = 1.74, 95% CI = 1.10-2.75), baseline CD4 ≥ 100 cells/μL (aOR = 2.06, 95% CI = 1.24-3.42), ARVT including AZT (aOR = 4.57, 95% CI=1.06-19.76), and the occurrence of a severe opportunistic infection during the first semester of ARVT (aOR = 2.38 95% CI= 1.49-3.80) were associated with SIR. After six months of ARVT and up to seven years of follow-up, 39 patients with SIR had presented with an opportunistic infection or death (rate= 9.78/100 person-years) compared to 168 with a normal recovery (rate = 7.75/100 person-years) but the difference was not statistically significant (aHR = 1.22, 95% CI = 0.85 to 1.74).

CONCLUSION

SIR is less common in our country and is not associated with increased mortality or a greater incidence of opportunistic infections after six months of ARVT.

A national cohort of HIV-infected patients in Belgium: design and main characteristics

In Belgium, individual laboratory and treatment data of all HIV-infected patients seen in the 9 AIDS Reference Centres and 7 AIDS Reference Laboratories are collected prospectively since 2006. We present here an analysis of patients recorded in the cohort database between 1st of January 2006 and 31st of December 2008. During that period, 11982 patients were under medical follow-up in Belgium. Sixty-one percent of the patients were male and the median age was 39.8 at the time of first recorded viral load. Among the patients whose nationality or probable mode of transmission was recorded, nearly half (48.0%) were Belgian and 38.3% originated from Sub-Saharan Africa; heterosexual contacts were reported in the majority of cases (56.0%) followed by homosexual contacts (35.3%). A total of 145 deaths were reported. Around three quarters of the patients were on ART. The median CD4 cell count rose from 470 cells/mm3 in 2006 to 501 cells/mm3 in 2008. This cohort enabled us to obtain comprehensive information on the numbers and characteristics of HIV-infected patients currently being followed up in Belgium, and on trends in antiretroviral therapy and biological results. This will serve for planning purposes, evaluation of access to care and as a source of information for further studies.

A venue-based HIV prevalence and behavioural study among men who have sex with men in Antwerp and Ghent, Flanders, Belgium, October 2009 to March 2010

Binary file ES_Abstracts_Final_ECDC.txt matches

A venue-based HIV prevalence and behavioural study among men who have sex with men in Antwerp and Ghent, Flanders, Belgium, October 2009 to March 2010

This venue-based, cross-sectional study reports on human immunodeficiency virus (HIV) prevalence and behaviour of 649 men who have sex with men (MSM) in Antwerp and Ghent, Flanders, Belgium, from October 2009 to March 2010. Using time-location sampling, we found that HIV prevalence in MSM who attended different types of venue ranged from a high of 14.5% (95% CI: 8.9–20.1; n=22 in cruising venues to 4.9% (95% CI: 1.9–7.9; n=10) in more general gay venues to 1.4% (95% CI: 0.0–3.6; n=3) at younger MSM venues. Of those who tested HIV positive (n=35, five were unaware of their HIV status or self-reported as being HIV negative. One in five respondents were of non-Belgian nationality. The results showed relatively high rates of testing for HIV (52.2%; 95 % CI: 47.8–56.2; n=288) and other sexually transmitted infections (STIs) (57.4%; 95% CI: 52.6–62.0; n=248) in the last 12 months. A majority of the men (n=233) used condoms consistently during their last anal sexual contact with a casual partner; however, HIV-positive men who were aware of their serostatus (n=30) reported less condom use with casual partners. This is the first such study in Belgium and the results constitute the evidence base for local, targeted interventions. Furthermore, our findings underscore the need for European cross-border cooperation to prevent HIV infection and other STIs among MSM.

Molecular typing of the actin gene of Trichomonas vaginalis isolates by PCR-restriction fragment length polymorphism

Human trichomoniasis, caused by the protozoan Trichomonas vaginalis, is a highly prevalent sexually transmitted infection. However, little is known about the degree of strain variability of T. vaginalis. A reliable classification method for T. vaginalis strains would be a useful tool in the study of the epidemiology, pathogenesis and transmission of T. vaginalis. A PCR-restriction fragment length polymorphism typing method was designed and evaluated using T. vaginalis isolates obtained after culture of vaginal specimens collected in the Democratic Republic of Congo and in Zambia. The variation of the actin gene of T. vaginalis was determined for three ATCC reference strains and 151 T. vaginalis isolates. Eight different types were identified, on the basis of the digestion patterns of the amplified actin gene, with each of the restriction enzymes HindII, MseI and RsaI. It was determined that the ATCC reference strains 30001, 30240 and 50141 were of actin genotypes G, H and E, respectively. The actin genotype type E was more common in the Democratic Republic of Congo, whereas type G was the commonest type in Zambia. Translation of the nucleotide sequence showed up to three amino acid substitutions. We developed a reproducible, sensitive and specific typing method for T. vaginalis, and were able to distinguish at least eight T. vaginalis actin genotypes. Further studies are needed to evaluate the method using clinical specimens and to determine the utility of the typing method for the genotypic characterization of T. vaginalis.

Population-level effect of HSV-2 therapy on the incidence of HIV in sub-Saharan Africa

BACKGROUND

Herpes simplex virus type 2 (HSV-2) infection increases acquisition and transmission of HIV, but the results of trials measuring the impact of HSV-2 therapy on HIV genital shedding and HIV acquisition are mixed, and the potential impact of HSV-2 therapy on the incidence of HIV at the population level is unknown.

METHODS

The effects of episodic and suppressive HSV-2 therapy were simulated using the individual-level model STDSIM fitted to data from Cotonou, Benin (relatively low HIV prevalence) and Kisumu, Kenya (high HIV prevalence). Clinician- and patient-initiated episodic therapy, started when symptomatic, were assumed to reduce ulcer duration. Suppressive therapy, given regardless of symptoms, was also assumed to reduce ulcer frequency and HSV-2 infectiousness.

RESULTS

Clinician-initiated episodic therapy in the general population had almost no effect on the incidence of HIV. The impact of patient-initiated therapy was higher because of earlier treatment initiation, but still low (<5%) unless symptom recognition and treatment-seeking behaviour were very high. Suppressive therapy given to female sex workers (FSW) in Kisumu had little effect on population HIV incidence. In Cotonou, suppressive therapy in FSW with high coverage and long duration reduced population HIV incidence by >20% in the long term. Impact was increased in both cities by also treating a proportion of their clients. Long-term suppressive therapy with high coverage in the general population could reduce HIV incidence by more than 30%.

CONCLUSIONS

These results show that HSV-2 therapy could potentially have a population-level impact on the incidence of HIV, especially in more concentrated epidemics. However, a substantial impact requires high coverage and long duration therapy, or very high symptom recognition and treatment-seeking behaviour.

Estimates of the number of female sex workers in different regions of the world

OBJECTIVES

To collect estimated numbers of female sex workers (FSW) and present proportions of FSW in the female population (FSW prevalence) in different regions of the world.

METHODS

Subnational and national estimated numbers of FSW reported in published and unpublished literature, as well as from field investigators involved in research or interventions targeted at FSW, were collected. The proportion of FSW in the adult female population was calculated. Subnational estimates were extrapolated to national estimates if appropriate. Population surveys were scanned for proportions of adult women having sex in exchange for money or goods.

RESULTS

In sub-Saharan Africa, the FSW prevalence in the capitals ranged between 0.7% and 4.3% and in other urban areas between 0.4% and 4.3%. Population surveys from this same region yielded even higher proportions of women involved in transactional sex. The national FSW prevalence in Asia ranged between 0.2% and 2.6%; in the ex-Russian Federation between 0.1% and 1.5%; in East Europe between 0.4% and 1.4%; in West Europe between 0.1% and 1.4%; and in Latin America between 0.2% and 7.4%. Estimates from rural areas were only available from one country.

CONCLUSIONS

Although it is well known and accepted that FSW are a highly vulnerable group in the scope of the HIV epidemic, most countries in the world do not know the size of this population group. The estimates of the prevalence of FSW presented in this paper show how important this hard-to-reach population group is in all parts of the world.

Role of core and bridging groups in the transmission dynamics of HIV and STIs in Cotonou, Benin, West Africa

The potential for exposure of low and high risk women to HIV and sexually transmitted infections (STI) through unprotected sex with male clients of female sex workers in Cotonou could account for most if not all of the estimated yearly numbers of HIV infections in Cotonou women (approximately 1000). As ongoing transmission of HIV, and also of the most predominant STIs such as gonorrhoea and HSV-2, appears to be largely fuelled by transmission within core and bridging groups in Cotonou, interventions targeted at both female sex workers and their male clients remain of the utmost importance and could have a significant effect on the evolution of HIV/STI epidemics in Benin.

How many patients with a sexually transmitted infection are cured by health services? A study from Mwanza region, Tanzania

OBJECTIVES

To estimate the proportion of symptomatic patients with a bacterial sexually transmitted infection (STI) cured by primary health care services in Mwanza Region, Tanzania, and to compare the cure rate achieved by health centres before and after the introduction of improved STI treatment services.

METHODS

A model was used that describes the different hurdles patients with an STI take before they can be considered cured by the health services. The values for the input parameters for the model were taken from different studies. Data from an intervention trial as well as from a population-based study on male urethritis were used to estimate the proportion of symptomatic patients with an STI who seek care from a health centre. An observational study in four health centres where improved STI treatment services had been introduced provided estimates of the proportions of patients with an STI correctly diagnosed and treated. Patients who returned to the health centres after 1 week were interviewed about compliance. An estimate of the efficacy of treatments prescribed for STIs in health centres before the introduction of improved STI services was obtained from a study on prescription patterns for genital discharge syndrome (GDS) and genital ulcer disease (GUD).

RESULTS

It was estimated that in the catchment area of health centres offering improved STI services, 51-72% of patients with STI symptoms sought care from those health centres. About 76-85% of cases were correctly diagnosed, and of these 69-80% received efficacious treatment. Compliance with full treatment was estimated at 84%. The estimated overall cure rate achieved by the health centres offering improved STI services ranged between 23 and 41%. The proportion of symptomatic STI patients who attended a health centre before improved STI services were introduced was estimated at 39%. The estimated efficacy of the treatments prescribed was 28%. The overall cure rate achieved by these health centres was less than 10%.

CONCLUSIONS

When assessing the performance of STI case detection and management all steps have to be taken into account that are taken by patients with an STI before they can be considered cured by the health services. The intervention to improve STI services in Mwanza Region has resulted in an improvement of the cure rate of STIs achieved by primary health care centres.

Factors influencing the difference in HIV prevalence between antenatal clinic and general population in sub-Saharan Africa

OBJECTIVE

To compare HIV prevalence in antenatal clinics (ANC) and the general population, and to identify factors determining the differences that were found.

DESIGN

Cross-sectional surveys in the general population and in ANC in three cities.

METHODS

HIV prevalence measured in adults in the community was compared with that measured by sentinel surveillance in ANC in Yaoundé, Cameroon, Kisumu, Kenya, and Ndola, Zambia.

RESULTS

In Yaoundé and Ndola, the HIV prevalence in ANC attenders was lower than that in women in the population overall, and for age groups over 20 years. In Kisumu, the HIV prevalence in ANC attenders was similar to that in women in the population at all ages. The only factors identified that influenced the results were age, marital status, parity, schooling, and contraceptive use. The HIV prevalence in women in ANC was similar to that in the combined male and female population aged 15-40 years in Yaoundé and Ndola, but overestimated it in Kisumu. In Yaoundé and Ndola, the overall HIV prevalence in men was approximated by using the age of the father of the child reported by ANC attenders, but this method overestimated the HIV prevalence in Kisumu, and did not give good age-specific estimates.

CONCLUSION

Few factors influenced the difference in HIV prevalence between ANC and the population, which could aid the development of adjustment procedures to estimate population HIV prevalence. However, the differences between cities were considerable, making standard adjustments difficult. The method of estimating male HIV prevalence should be tested in other sites.

HIV-1 subtypes and the HIV epidemics in four cities in sub-Saharan Africa

OBJECTIVE

To describe the distribution of HIV-1 subtypes in two cities with high HIV prevalence (Kisumu, Kenya and Ndola, Zambia) and two with relatively low prevalence (Cotonou, Benin and Yaoundé, Cameroon), and to examine whether the differences in prevalence of HIV infection could be due to the predominance within the infected populations of subtypes with differing efficiency of heterosexual transmission.

METHODS

For around 100 randomly selected HIV-positive sera from the general population and 60 from sex workers in each city, the HIV-1 subtype was determined in the envfragment. For between 19 and 52 of the sera from the general population and 20-32 sera from sex workers, the subtype was also determined in the gag fragment.

RESULTS

Over 70% of infections in Cotonou, Yaoundé and Kisumu were with subtype A (by env). However, around one-half of subtype A infections in Cotonou and Yaoundé were found to be the circulating recombinant form CRF02_AG when the gag fragment was also examined. A large number of different HIV strains were found in Yaoundé, including some belonging to group O. Over 20% of infections in Kisumu and around 10% in Yaoundé were with isolated intersubtype recombinant forms. All but a few infections in Ndola were with subtype C and no recombinants were found.

CONCLUSIONS

The pattern of distribution of subtypes that we found does not suggest that differences in circulating subtypes play a major role in explaining the differences in prevalence of HIV-1 infection between the four cities. The emergence and spread of recombinants requires close surveillance to adapt testing strategies if needed, to inform vaccine development and to ascertain their role in the future spread of HIV.

Condom use and its association with HIV/sexually transmitted diseases in four urban communities of sub-Saharan Africa

OBJECTIVES

To estimate rates of condom use in four urban populations in sub-Saharan Africa and to assess their association with levels of HIV infection and other sexually transmitted diseases (STDs).

METHODS

Data were obtained from a multicentre study of factors that determine the differences in rate of spread of HIV in four African cities. Consenting participants were interviewed on sexual behaviour, and also provided blood and urine samples for testing for HIV infection and other STDs. Data on sexual behaviour included information on condom use during all reported spousal and non-spousal partnerships in the past 12 months.

RESULTS

A total of 2116 adults aged 15-49 years were interviewed in Cotonou (Benin), 2089 in Yaoundé (Cameroon), 1889 in Kisumu (Kenya) and 1730 in Ndola (Zambia). Prevalence rates of HIV infection were 3.4% in Cotonou, 5.9% in Yaoundé, 25.9% in Kisumu and 28.4% in Ndola. Reported condom use was low, with the proportions of men and women who reported frequent condom use with all non-spousal partners being 21-25%, for men and 11-24% for women. A higher level of condom use by city was not associated with lower aggregate level of HIV infection. The proportions of men reporting genital pain or discharge during the past 12 months were significantly lower among those reporting frequent condom use in all sites except Yaoundé: in Cotonou, adjusted odds ratio (OR) = 0.28, 95% confidence interval (CI) = 0.09-0.94; in Kisumu, adjusted OR = 0.34, 95% CI = 0.14-0.83; and in Ndola, adjusted OR = 0.33, 95% CI = 0.12-0.90. The same association was found for reported genital ulcers in two sites only: in Cotonou, adjusted OR = 0.14, 95% CI = 0.02-1.02; and in Kisumu, adjusted OR = 0.18, 95% CI = 0.04-0.75. There were few statistically significant associations between condom use and biological indicators of HIV infection or other STDs in any of the cities.

CONCLUSION

Similar levels of condom use were found in all four populations, and aggregate levels of condom use by city could not discriminate between cities with high and low level of HIV infection. It seems that rates of condom use may not have been high enough to have a strong impact on HIV/STD levels in the four cities. At an individual level, only a male history of reported STD symptoms was found to be consistently associated with lower rates of reported condom use.

Commercial sex and the spread of HIV in four cities in sub-Saharan Africa

OBJECTIVE

To examine whether commercial sex transactions were more common and/or transmission between sex workers and clients more efficient in two African cities with high HIV prevalence (Kisumu, Kenya and Ndola, Zambia) compared with two with relatively low HIV prevalence (Cotonou, Benin and Yaoundé, Cameroon).

METHODS

Data on sexual behaviour, HIV and sexually transmitted infections were collected from representative samples of around 300 female sex workers in each city. Sexual behaviour data from a population-based study of around 1000 men aged 15-49 in each city were used to estimate the extent of contact with sex workers.

RESULTS

The number of sex workers per 1000 males was highest in Kisumu and Ndola, but other estimates of the extent or characteristics of sex work contact showed no consistent differences between high or low prevalence cities. HIV prevalence among sex workers was 75% in Kisumu, 69% in Ndola, 55% in Cotonou and 34% in Yaoundé. The prevalence of genital ulceration and trichomoniasis was higher among sex workers in Kisumu and Ndola but no clear pattern was seen for the other sexually transmitted infections. Around 70% of sex workers in Cotonou reported use of a condom with the last client, markedly higher than in the other cities.

CONCLUSIONS

Although sex work is likely to have played an important role in the spread of HIV in all four cities, differences in present patterns of sex work do not appear to explain the differential spread of HIV. However, high levels of condom use among sex workers may have slowed the spread from sex workers to the general population in Cotonou, highlighting the importance of interventions among sex workers and their clients.

Ecological and individual level analysis of risk factors for HIV infection in four urban populations in sub-Saharan Africa with different levels of HIV infection

OBJECTIVE

To identify factors that could explain differences in rate of spread of HIV between different regions in sub-Saharan Africa.

DESIGN

Cross-sectional study.

METHODS

The study took place in two cities with a relatively low HIV prevalence (Cotonou, Benin and Yaoundé, Cameroon), and two cities with a high HIV prevalence (Kisumu, Kenya and Ndola, Zambia). In each of these cities, a representative sample was taken of about 1000 men and 1000 women aged 15-49 years. Consenting men and women were interviewed about their socio-demographic background and sexual behaviour; and were tested for HIV, herpes simplex virus type 2 (HSV-2), syphilis, Chlamydia trachomatis and Neisseria gonorrhoea infection, and (women only) Trichomonas vaginalis. Analysis of risk factors for HIV infection was carried out for each city and each sex separately. Adjusted odds ratios (aOR) were obtained by multivariate logistic regression.

RESULTS

The prevalence of HIV infection in sexually active men was 3.9% in Cotonou, 4.4% in Yaoundé, 21.1% in Kisumu, and 25.4% in Ndola. For women, the corresponding figures were 4.0, 8.4, 31.6 and 35.1%. High-risk sexual behaviour was not more common in the high HIV prevalence cities than in the low HIV prevalence cities, but HSV-2 infection and lack of circumcision were consistently more prevalent in the high HIV prevalence cities than in the low HIV prevalence cities. In multivariate analysis, the association between HIV infection and sexual behavioural factors was variable across the four cities. Syphilis was associated with HIV infection in Ndola in men [aOR = 2.7, 95% confidence interval (CI) = 1.5-4.91 and in women (aOR = 1.7, 95% CI = 1.1-2.6). HSV-2 infection was strongly associated with HIV infection in all four cities and in both sexes (aOR ranging between 4.4 and 8.0). Circumcision had a strong protective effect against the acquisition of HIV by men in Kisumu (aOR = 0.25, 95% CI = 0.12-0.52). In Ndola, no association was found between circumcision and HIV infection but sample sizes were too small to fully adjust for confounding.

CONCLUSION

The strong association between HIV and HSV-2 and male circumcision, and the distribution of the risk factors, led us to conclude that differences in efficiency of HIV transmission as mediated by biological factors outweigh differences in sexual behaviour in explaining the variation in rate of spread of HIV between the four cities.

The epidemiology of gonorrhoea, chlamydial infection and syphilis in four African cities

OBJECTIVES

To compare the epidemiology of gonorrhoea, chlamydial infection and syphilis in four cities in sub-Saharan Africa; two with a high prevalence of HIV infection (Kisumu, Kenya and Ndola, Zambia), and two with a relatively low HIV prevalence (Cotonou, Benin and Yaoundé, Cameroon).

DESIGN

Cross-sectional study, using standardized methods, including a standardized questionnaire and standardized laboratory tests, in four cities in sub-Saharan Africa.

METHODS

In each city, a random sample of about 2000 adults aged 15-49 years was taken. Consenting men and women were interviewed about their socio-demographic characteristics and their sexual behaviour, and were tested for HIV, syphilis, herpes simplex virus type 2 (HSV-2), gonorrhoea, chlamydial infection, and (women only) Trichomonas vaginalis infection. Risk factor analyses were carried out for chlamydial infection and syphilis seroreactivity.

RESULTS

The prevalence of gonorrhoea ranged between 0% in men in Kisumu and 2.7% in women in Yaoundé. Men and women in Yaoundé had the highest prevalence of chlamydial infection (5.9 and 9.4%, respectively). In the other cities, the prevalence of chlamydial infection ranged between 1.3% in women in Cotonou and 4.5% in women in Kisumu. In Ndola, the prevalence of syphilis seroreactivity was over 10% in both men and women; it was around 6% in Yaoundé, 3-4% in Kisumu, and 1-2% in Cotonou. Chlamydial infection was associated with rate of partner change for both men and women, and with young age for women. At the population level, the prevalence of chlamydial infection correlated well with reported rates of partner change. Positive syphilis serology was associated with rate of partner change and with HSV-2 infection. The latter association could be due to biological interaction between syphilis and HSV-2 or to residual confounding by sexual behaviour. At the population level, there was no correlation between prevalence of syphilis seroreactivity and reported rates of partner change.

CONCLUSION

Differences in prevalence of chlamydial infection could be explained by differences in reported sexual behaviour, but the variations in prevalence of syphilis seroreactivity remained unexplained. More research is needed to better understand the epidemiology of sexually transmitted infections in Africa.

Comparison of key parameters of sexual behaviour in four African urban populations with different levels of HIV infection

OBJECTIVE

To explore whether differences in sexual behaviour could explain differences in the rate of spread of HIV in four urban populations in Africa.

METHODS

A cross-sectional, population-based study was conducted in two cities where the prevalence of HIV among adults exceeded 20% (Kisumu, Kenya and Ndola, Zambia) and two cities with a much lower HIV prevalence among adults (Cotonou, Benin and Yaoundé, Cameroon). In each of these cities, approximately 1000 men and 1000 women, aged 15-49 years, were randomly selected from the general population. Consenting men and women were interviewed about their sociodemographic characteristics and sexual behaviour, including characteristics of spouses and of non-spousal partners. Key parameters of sexual behaviour were compared between the four cities.

RESULTS

On average, women in the high HIV prevalence cities had their sexual debut earlier than in the other cities. Men and women in Kisumu and Ndola got married earlier than men and women in Cotonou and Yaoundé. High rates of partner change, contacts with sex workers, concurrent partnerships and large age differences between partners were no more common in the two high HIV prevalence cities than in the two low HIV prevalence cities.

CONCLUSIONS

In these four African populations, differences in reported sexual behaviour could not explain the differences in rate of spread of HIV. In all four cities, high-risk sexual behaviour patterns were identified.

Multicentre study on factors determining differences in rate of spread of HIV in sub-Saharan Africa: methods and prevalence of HIV infection

OBJECTIVE

The objective of this study was to explore whether the differences in rate of spread of HIV in different regions in sub-Saharan Africa could be explained by differences in sexual behaviour and/or factors influencing the probability of HIV transmission during sexual intercourse.

METHODS

A cross-sectional, population-based study was conducted in two cities with a high HIV prevalence (Kisumu in Kenya and Ndola in Zambia) and two cities with a relatively low HIV prevalence (Cotonou in Benin and Yaoundé in Cameroon). In each of these cities, approximately 1000 men and 1000 women, aged 15-49 years, were randomly selected from the general population. Consenting men and women were interviewed and were tested for HIV, syphilis, herpes simplex virus type 2 (HSV-2), gonorrhoea, chlamydial infection and trichomoniasis (the latter for women only). In addition, a survey was conducted on a random sample of 300 sex workers in each city. The research instruments, including the questionnaires and the laboratory procedures, were standardized to permit comparison of results.

RESULTS

The numbers of men interviewed were 1021 in Cotonou, 973 in Yaoundé, 829 in Kisumu, and 720 in Ndola. The corresponding figures for women were 1095, 1116, 1060 and 1130. In Yaoundé, Kisumu and Ndola, the response rates for men were lower than for women due to failure to make contact with eligible men. The proportion of eligible women who were interviewed was 86% in Yaoundé, and 89% in Kisumu and Ndola. In Yaoundé, 76% of eligible men were interviewed, along with 82% in Kisumu and 75% in Ndola. The prevalence of HIV infection in men was 3.3% in Cotonou, 4.1% in Yaoundé, 19.8% in Kisumu and 23.2% in Ndola. For women, the respective figures were 3.4, 7.8, 30.1 and 31.9%. The prevalence of HIV infection among women aged 15-19 years was 23.0% in Kisumu and 15.4% in Ndola. Among women in Kisumu who had their sexual debut 5 years before the interview, the prevalence of HIV infection was 46%; in Ndola, it was 59%. Among sex workers, the prevalence of HIV infection was 57.5% in Cotonou, 34.4% in Yaoundé, 74.7% in Kisumu and 68.7% in Ndola.

CONCLUSIONS

The HIV prevalence rates in the general population confirmed our preliminary assessment of the level of HIV infection in the four cities, which was based on estimates of HIV prevalence from sentinel surveillance among pregnant women. The very high prevalence of HIV infection among young women in Kisumu and Ndola calls for urgent intervention.

Male circumcision and HIV infection in four cities in sub-Saharan Africa

OBJECTIVES

To explore the role of male circumcision in the spread of HIV infection in four urban populations in sub-Saharan Africa.

DESIGN AND METHODS

A cross-sectional population based study was conducted in four cities in sub-Saharan Africa with different levels of HIV infection. HIV prevalence among adults was relatively low in Cotonou (Benin) and in Yaoundé (Cameroon), and exceeded 25% in Kisumu (Kenya) and in Ndola (Zambia). In each city, a random sample was taken of men and women aged 15-49 years from the general population. Consenting study participants were interviewed about their sociodemographic characteristics and their sexual behaviour, and were tested for HIV, herpes simplex virus type 2, syphilis, gonorrhoea and chlamydial infection. Men underwent a genital examination.

RESULTS

In Cotonou and in Yaoundé, the two low HIV prevalence cities, 99% of men were circumcised. In Kisumu 27.5% of men were circumcised, and in Ndola this proportion was 9%. In Kisumu, the prevalence of HIV infection was 9.9% among circumcised men and 26.6% among uncircumcised men. After controlling for socio-demographic characteristics, sexual behaviour and other sexually transmitted infections, the protective effect of male circumcision remained with an adjusted odds ratio of 0.26 (95% confidence interval = 0.12-0.56). In Ndola, the prevalence of HIV infection was 25.0% in circumcised men and 26.0% in uncircumcised men. The power was insufficient to adjust for any differences in sexual behaviour.

CONCLUSIONS

The differences in epidemic spread of HIV are likely to be due to differences in the probability of transmission of HIV during sexual exposure as well as differences in sexual behaviour. Male circumcision is one of the factors influencing the transmission of HIV during sexual intercourse, and this study confirms the population level association between HIV and lack of male circumcision, as well as a strong individual level association in Kisumu, the only city with sufficient power to analyze this association.

Interpreting sexual behaviour data: validity issues in the multicentre study on factors determining the differential spread of HIV in four African cities

BACKGROUND

The main conclusion of the multicentre study on factors determining the differential spread of HIV in four African cities was that differences in sexual behaviour could not, by themselves, explain the differences in HIV prevalence between the four cities. The present paper examines three potential sources of bias that could invalidate this conclusion: (1) changes in sexual behaviour since the start of the HIV epidemics; (2) bias due to the low response rates of men; and (3) bias in reported sexual behaviour.

METHODS

To assess whether there have been any changes in sexual behaviour over time, selected parameters of sexual behaviour were compared between different age groups in the four cities. The maximum likely extent of bias due to non-participation of men in Yaoundé, Kisumu and Ndola was assessed with a simulation exercise, in which records of non-participants were replaced with records of 'low activity men' in Yaoundé and 'high activity men' in Kisumu and Ndola. To assess the validity of the sexual behaviour data, internal validity checks were carried out: comparing biological data on sexually transmitted infections with reports; comparing reports of spouses; and comparing numbers of sex partners reported by men and women. A fourth method consisted of comparing the findings of the multicentre study with an external source, Demographic and Health Surveys (DHS).

RESULTS

There were differences in sexual behaviour between the younger and the older age groups in all four cities but there was no evidence of a shift towards safer sexual behaviour in the high HIV prevalence cities. After simulating results for male non-participants in Yaoundé, Kisumu and Ndola, the median lifetime number of sex partners was similar in Yaoundé, Kisumu and Ndola. By testing for various sexually transmitted infections among men and women aged 15-24 years who reported that they had never had sexual intercourse, we could establish that, in all four cities, at least 1-9% of men and 6-18% of women had misreported their sexual activity. The number of non-spousal partners in the past 12 months reported by men was two to three times higher than the number reported by women, as has been found in other studies. The most consistent differences between our survey and the DHS were found in the numbers of non-spousal partners in the past 12 months reported by never-married men and women. In all four cities, participants reported more non-spousal partners in the DHS than in our survey.

CONCLUSIONS

In all four cities, we found evidence that men as well as women misreported their sexual behaviour, but overall it seems that under-reporting of sexual activity was not more common or more serious in the two high HIV prevalence cities than in the two low HIV prevalence cities. We believe that the main conclusions of the multicentre study still hold.

The epidemiology of HSV-2 infection and its association with HIV infection in four urban African populations

OBJECTIVES

To estimate age- and sex-specific herpes simplex virus type-2 (HSV-2) prevalence in urban African adult populations and to identify factors associated with infection.

DESIGN AND METHODS

Cross-sectional, population-based samples of about 2000 adults interviewed in each of the following cities: Cotonou, Benin; Yaoundé, Cameroon; Kisumu, Kenya and Ndola, Zambia. Consenting study participants were tested for HIV, HSV-2 and other sexually transmitted infections.

RESULTS

HSV-2 prevalence was over 50% among women and over 25% among men in Yaoundé, Kisumu and Ndola, with notably high rates of infection among young women in Kisumu and Ndola (39% and 23%, respectively, among women aged 15-19 years). The prevalence in Cotonou was lower (30% in women and 12% in men). Multivariate analysis showed that HSV-2 prevalence was significantly associated with older age, ever being married, and number of lifetime sexual partners, in almost all cities and both sexes. There was also a strong, consistent association with HIV infection. Among women, the adjusted odds ratios for the association between HSV-2 and HIV infections ranged from 4.0 [95% confidence interval (CI) = 2.0-8.0] in Kisumu to 5.5 (95% CI = 1.7-18) in Yaoundé, and those among men ranged from 4.6 (95% CI = 2.7-7.7) in Ndola to 7.9 (95% CI = 4.1-15) in Kisumu.

CONCLUSIONS

HSV-2 infection is highly prevalent in these populations, even at young ages, and is strongly associated with HIV at an individual level. At a population level, HSV-2 prevalence was highest in Kisumu and Ndola, the cities with the highest HIV rates, although rates were also high among women in Yaoundé, where there are high rates of partner change but relatively little HIV infection. The high prevalence of both infections among young people underlines the need for education and counselling among adolescents.

The epidemiology of trichomoniasis in women in four African cities

OBJECTIVES

To describe the epidemiology of Trichomonas vaginalis infection and its association with HIV infection, in women in four African cities with different levels of HIV infection.

DESIGN

Cross-sectional study, using standardized methods, including a standardized questionnaire and standardized laboratory tests, in four cities in sub-Saharan Africa: two with a high prevalence of HIV infection (Kisumu, Kenya and Ndola, Zambia), and two with a relatively low prevalence of HIV (Cotonou, Benin and Yaoundé, Cameroon).

METHODS

In each city, a random sample of about 2000 adults aged 15-49 years was taken. Consenting men and women were interviewed about their socio-demographic characteristics and their sexual behaviour, and were tested for HIV, syphilis, herpes simplex virus type 2 (HSV-2), gonorrhoea, chlamydial infection, and (women only) T. vaginalis infection. Risk factor analyses were carried out for trichomoniasis for each city separately. Multivariate analysis, however, was only possible for Yaoundé, Kisumu and Ndola.

RESULTS

The prevalence of trichomoniasis was significantly higher in the high HIV prevalence cities (29.3% in Kisumu and 34.3% in Ndola) than in Cotonou (3.2%) and Yaoundé (17.6%). Risk of trichomoniasis was increased in women who reported more lifetime sex partners. HIV infection was an independent risk factor for trichomonas infection in Yaoundé [adjusted odds ratio (OR) = 1.8, 95% confidence interval (CI) = 0.9-3.7] and Kisumu (adjusted OR = 1.7, 95% CI = 1.1-2.7), but not in Ndola. A striking finding was the high prevalence (40%) of trichomonas infection in women in Ndola who denied that they had ever had sex.

CONCLUSION

Trichomoniasis may have played a role in the spread of HIV in sub-Saharan Africa and may be one of the factors explaining the differences in levels of HIV infection between different regions in Africa. The differences in prevalence of trichomoniasis between the four cities remain unexplained, but we lack data on the epidemiology of trichomoniasis in men. More research is required on the interaction between trichomoniasis and HIV infection, the epidemiology of trichomoniasis in men, and trichomonas infections in women who deny sexual activity.

Why do young women have a much higher prevalence of HIV than young men? A study in Kisumu, Kenya and Ndola, Zambia

OBJECTIVE

To examine the factors responsible for the disparity in HIV prevalence between young men and women in two urban populations in Africa with high HIV prevalence.

DESIGN

Cross-sectional survey, aiming to include 1000 men and 1000 women aged 15-49 years in Kisumu, Kenya and Ndola, Zambia.

METHODS

Participants were interviewed and tested for HIV and other sexually transmitted infections. Analyses compared the marital and non-marital partnership patterns in young men and women, and estimated the likelihood of having an HIV-infected partner.

RESULTS

Overall, 26% of individuals in Kisumu and 28% in Ndola were HIV-positive. In both sites, HIV prevalence in women was six times that in men among sexually active 1 5-19 year olds, three times that in men among 20-24 year olds, and equal to that in men among 25-49 year olds. Age at sexual debut was similar in men and women, and men had more partners than women. Women married younger than men and marriage was a risk factor for HIV, but the disparity in HIV prevalence was present in both married and unmarried individuals. Women often had older partners, and men rarely had partners much older than themselves. Nevertheless, the estimated prevalence of HIV in the partners of unmarried men aged under 20 was as high as that for unmarried women. HIV prevalence was very high even among women reporting one lifetime partner and few episodes of sexual intercourse.

CONCLUSIONS

Behavioural factors could not fully explain the discrepancy in HIV prevalence between men and women. Despite the tendency for women to have older partners, young men were at least as likely to encounter an HIV-infected partner as young women. It is likely that the greater susceptibility of women to HIV infection is an important factor both in explaining the male-female discrepancy in HIV prevalence and in driving the epidemic. Herpes simplex virus type 2 infection, which is more prevalent in young women than in young men, is probably one of the factors that increases women's susceptibility to HIV infection.

Educational level is associated with condom use within non-spousal partnerships in four cities of sub-Saharan Africa

BACKGROUND

Rates of condom use in sub-Saharan Africa have remained too low to curb HIV/sexually transmitted disease (STD) epidemics. A better understanding of the main determinants of condom use would aid promotion.

METHODS

Cross-sectional population surveys were conducted in four cities in sub-Saharan Africa: Yaoundé, Cameroon; Cotonou, Benin; Ndola, Zambia; and Kisumu, Kenya. In each city, the aim was to interview a random sample of 1000 men and 1000 women aged 15--49 years, including questions on characteristics of non-spousal partnerships in the past 12 months.

RESULTS

Data on condom use were available for 4624 non-spousal partnerships. In the four cities, the proportion of partnerships in which condoms were used always or most of the time ranged from 23.8 to 33.5% when reported by men and from 10.7 to 25.9% when reported by women. Based on the reports from men, condom use was associated with higher educational level of the male partner in Yaoundé [adjusted odds ratio (aOR) = 1.76] and Ndola (aOR = 2.94) and with higher educational level of the female partner in Cotonou (aOR = 2.36) and Kisumu (aOR = 2.76). Based on the reports from women, condom use was associated with higher educational level of the female partner in Kisumu (aOR = 2.60) and Ndola (aOR = 4.50) and with higher educational level of the male partner in Yaoundé (aOR = 3.32). Associations with other determinants varied across cities and for men and women.

CONCLUSIONS

Education was found to be a key determinant of condom use in all four cities. This suggests that educational level increases response to condom promotion and highlights the need for special efforts to reach men and women with low educational attainment.

Concurrent sexual partnerships and HIV prevalence in five urban communities of sub-Saharan Africa

OBJECTIVE

To estimate parameters of concurrent sexual partnerships in five urban populations in sub-Saharan Africa and to assess their association with levels of HIV infection and other sexually transmitted infections (STI).

METHODS

Data were obtained from a multicentre study of factors which determine the differences in rate of spread of HIV in five African cities. Consenting participants were interviewed on sexual behaviour and at four of the five sites also provided a blood and a urine sample for testing for HIV and other STI. Data on sexual behaviour included the number of partnerships in the 12 months preceding the interview as well as the dates of the start and end of each partnership. Summary indices of concurrent sexual partnerships -- some of which were taken from the literature, while others were newly developed -- were computed for each city and compared to HIV and STI prevalence rates.

RESULTS

A total of 1819 adults aged 15--49 years were interviewed in Dakar (Senegal), 2116 in Cotonou (Benin), 2089 in Yaoundé (Cameroon), 1889 in Kisumu (Kenya) and 1730 in Ndola (Zambia). Prevalence rates of HIV infection were 3.4% for Cotonou, 5.9% for Yaoundé, 25.9% for Kisumu and 28.4% for Ndola, and around 1% for Dakar. The estimated fraction of sexual partnerships that were concurrent at the time of interview (index k) was relatively high in Yaoundé (0.98), intermediate in Kisumu (0.44) and Cotonou (0.33) and low in Ndola (0.26) and in Dakar (0.18). An individual indicator of concurrency (iic) was developed which depends neither on the number of partners nor on the length of the partnerships and estimates the individual propensity to keep (positive values) or to dissolve (negative values) on-going partnership before engaging in another one. This measure iic did not discriminate between cities with high HIV infection levels and cities with low HIV infection levels. In addition, iic did not differ significantly between HIV-infected and uninfected people in the four cities where data on HIV status were collected.

CONCLUSION

We could not find evidence that concurrent sexual partnerships were a major determinant of the rate of spread of HIV in five cities in sub-Saharan Africa. HIV epidemics are the result of many factors, behavioural as well as biological, of which concurrent sexual partnerships are only one.

Decreased fertility among HIV-1-infected women attending antenatal clinics in three African cities

Population HIV prevalence estimates rely heavily on sentinel surveillance in antenatal clinics (ANCs), but because HIV reduces fertility, these estimates are biased. To aid interpretation of such data, we estimated HIV-associated fertility reduction among pregnant women in ANCs in Yaoundé (Cameroon), Kisumu (Kenya), and Ndola (Zambia). Data collection followed existing HIV sentinel surveillance procedures as far as possible. HIV prevalence among the women was 5.5% in Yaoundé, 30.6% in Kisumu, and 27.3% in Ndola. The birth interval was prolonged in HIV-positive multiparous women compared with HIV-negative multiparous women in all three sites: adjusted hazard ratios of pregnancy were 0.84 (95% confidence interval [CI]: 0.62-1.1) in Yaoundé, 0.82 (95% CI: 0.70-0.96) in Kisumu, and 0.74 (95% CI: 0.61-0.90) in Ndola, implying estimated reductions in the risk of pregnancy in HIV-positive women of between 16% and 26%. For primiparous women, the interval between sexual debut and birth was longer in HIV-positive women than in HIV-negative women in all sites, although the association was lost in Ndola after adjusting for age and other factors. Consistent results in different study sites help in the development of standard methods for improving ANC-based surveillance estimates of HIV prevalence. These may be easier to devise for multiparous women than for primiparous women.

Operational performance of an STD control programme in Mwanza Region, Tanzania

OBJECTIVES

To describe important details of the design and operational features of the Mwanza sexually transmitted diseases (STD) control programme. To assess the feasibility of the intervention, the distribution of STD syndromes observed, the clinical effectiveness of syndromic STD case management, the utilisation of STD services by the population, and the quality of syndromic STD services delivered at rural health units.

METHODS

The intervention was integrated into rural primary healthcare (PHC) units. It comprised improved STD case management using the syndromic approach, facilitated by a regional programme office which ensured the training of health workers, a reliable supply of effective drugs, and regular support supervision. Five studies were performed to evaluate operational performance: (i) a survey of register books to collect data on patients presenting with STDs and reproductive tract infections (RTIs) to rural health units with improved STD services, (ii) a survey of register books from health units in communities without improved services, (iii) a survey of register books from referral clinics, (iv) a home based cross sectional study of STD patients who did not return to the intervention health units for follow up, (v) a cross sectional survey of reported STD treatment seeking behaviour in a random cohort of 8845 adults served by rural health units.

RESULTS

During the 2 years of the Mwanza trial, 12,895 STD syndromes were treated at the 25 intervention health units. The most common syndromes were urethral discharge (67%) and genital ulcers (26%) in men and vaginal discharge (50%), lower abdominal tenderness (33%), and genital ulcers (13%) in women. Clinical treatment effectiveness was high in patients from whom complete follow up data were available, reaching between 81% and 98% after first line treatment and 97%-99% after first, second, and third line treatment. Only 26% of patients referred to higher levels of health care had presented to their referral institutions. During the trial period, data from the cohort showed that 12.8% of men and 8.6% of women in the intervention communities experienced at least one STD syndrome. Based on various approaches, utilisation of the improved health units by symptomatic STD patients in these communities was estimated at between 50% and 75%. During the first 6 months of intervention attendance at intervention units increased by 53%. Thereafter, the average attendance rate was about 25% higher than in comparison communities. Home visits to 367 non-returners revealed that 89% had been free of symptoms after treatment, but 28% became symptomatic again within 3 months of treatment. 100% of these patients reported that they had received treatment, but only 74% had been examined, only 57% had been given health education, and only 30% were offered condoms. Patients did not fully recall which treatment they had been given, but possibly only 63% had been treated exactly according to guidelines.

CONCLUSIONS

This study demonstrated that it is feasible to integrate effective STD services into the existing PHC structure of a developing country. Improved services attract more patients, but additional educational efforts are needed to further improve treatment seeking behaviour. Furthermore, clear treatment guidelines, a reliable drug supply system, and regular supervision are critical. All efforts should be made to treat patients on the spot, without delay, as referral to higher levels of care led to a high number of dropouts. The syndromic approach to STD control should be supported by at least one reference clinic and laboratory per country to ensure monitoring of prevalent aetiologies, of the development of bacterial resistance, and of the effectiveness of the syndromic algorithms in use.

High prevalence of trichomoniasis in rural men in Mwanza, Tanzania: results from a population based study

OBJECTIVES

To measure the prevalence of urethral infections including trichomoniasis in rural Tanzanian men, to assess the prevalence of symptoms and signs among men with Trichomonas vaginalis, and to analyse the risk factors for trichomoniasis.

DESIGN

A cross sectional study of 1004 men aged 15-54 years in a rural community in north west Tanzania.

METHODS

Participants were interviewed about sexual behaviour and symptoms of sexually transmitted diseases. First fraction urine samples and urethral swabs were collected and used to test for T vaginalis by wet preparation and culture, Neisseria gonorrhoeae by culture, Chlamydia trachomatis by ligase chain reaction and non-specific urethritis by Gram stain. Urine was also tested for the presence of leucocytes using a leucocyte esterase dipstick. Men were re-interviewed 2 weeks later to document new symptoms and signs of urethritis.

RESULTS

Complete laboratory results were available on 980 men. One in four men had laboratory evidence of urethritis. T vaginalis was found in 109 individuals (11%), gonorrhoea in eight (0.8%), and chlamydial infection in 15 (1.5%). Over 50% of men with urethritis were asymptomatic. The prevalence of signs and symptoms was similar among men with T vaginalis alone compared with men with other urethral infections. The sensitivity and specificity of the leucocyte esterase dipstick (LED) test for detecting T vaginalis were 80% and 48% respectively in symptomatic men and 60% and 68% in asymptomatic men. Factors associated with trichomoniasis included religion, type of employment, and marital status.

CONCLUSIONS

A high prevalence of urethritis was found in men in this community based study. More than half of the urethral infections detected were asymptomatic. The most prevalent pathogen was T vaginalis. Studies are needed on the prevalence of trichomoniasis in men presenting to health services with complaints suggestive of urethritis since treatment for T vaginalis is not included in the syndromic management of urethritis in most countries. The performance of the LED test as a screening test for trichomoniasis was unsatisfactory in both symptomatic and asymptomatic men. Improved screening tests are urgently needed to identify urethral infections that are asymptomatic and which are not covered by current syndromic management algorithms.

Simplified strategy for detection of recombinant human immunodeficiency virus type 1 group M isolates by gag/env heteroduplex mobility assay. Study Group on Heterogeneity of HIV Epidemics in African Cities

We developed a heteroduplex mobility assay in the gag gene (gag HMA) for the identification of group M subtypes A to H. The assay covers the region coding for amino acid 132 of p24 to amino acid 20 of p7 (according to human immunodeficiency virus type 1 [HIV-1] ELI, 460 bp). The gag HMA was compared with sequencing and phylogenetic analysis of an evaluation panel of 79 HIV-1 group M isolates isolated from infected individuals from different geographic regions. Application of gag HMA in combination with env HMA on 252 HIV-1- positive plasma samples from Bénin, Cameroon, Kenya, and Zambia revealed a high prevalence of a variety of intersubtype recombinants in Yaoundé, Cameroon (53.8%); Kisumu, Kenya (26.8%); and Cotonou, Bénin (41%); no recombinants were identified among the samples from Ndola, Zambia. The AG(IbNG) circulating recombinant form, as determined by gag HMA, was found to be the most common intersubtype recombinant in Yaoundé (39.4%) and Cotonou (38.5%). Using a one-tube reverse transcriptase PCR protocol, this gag HMA in combination with env HMA is a useful tool for rapidly monitoring the prevalence of the various genetic subtypes as well as of recombinants of HIV-1. Moreover, this technology can easily be applied in laboratories in developing countries.

AIDS and hospital bed occupancy: an overview

In several countries of sub-Saharan Africa more than 10% of the adult population are infected with HIV, while in large towns such as Kampala, Lusaka, Blantyre, Kigali and Harare this proportion exceeds 25%. One of the most obvious consequences is the increased occupancy of hospital beds by patients with HIV infection, perhaps to the exclusion of patients with other ailments. This paper gives an overview of several hospital occupancy studies.

Epidemiological and molecular characteristics of HIV infection in Gabon, 1986-1994

OBJECTIVE

To describe trends in the prevalence of HIV-1 infection in different populations in Gabon, and the molecular characteristics of circulating HIV strains.

METHODS

Data were collected on HIV prevalence through sentinel surveillance surveys in different populations in Libreville (the capital) and in Franceville. In Libreville, a total of 7082 individuals (hospitalized patients, tuberculosis patients, pregnant women, asymptomatic adults, prisoners) were recruited between 1986 and 1994. In Franceville, we tested 771 pregnant women and 886 healthy asymptomatic adults (1986-1988). Sera were screened for HIV antibodies by enzyme-linked immunosorbent assay (ELISA) and confirmed by Western blot or line immunoassay (LIA). Reactive samples in ELISA were tested for the presence of antibodies to HIV-1 group O viruses by ELISA using V3 peptides from HIV-1 ANT-70 and HIV-1 MVP-5180 followed by confirmation by LIA and a specific Western blot. Seventeen HIV-1 strains were isolated (1988-1993) and a 900 base-pair fragment encoding the env region containing V3, V4, V5 and beginning of gp41 was sequenced and a phylogenetic tree was constructed.

RESULTS

HIV prevalence was relatively low and remained stable (0.7-1.6% in pregnant women, 2.1-2.2% in the general population). The prevalence was also stable among prisoners (2.1-2.6%). Among hospitalized and tuberculosis patients prevalence was higher and increased (1.8-12.7% and 1.5-16.2%, respectively). Only three sera had antibodies to HIV-1 group O. The 17 HIV-1 strains represent six different genetic subtypes including type O.

CONCLUSION

Our data from 1986 to 1994 show a stable and low HIV prevalence in Gabon, and a high genetic diversity of HIV-1 strains. This, also observed in Cameroon, is in contrast to that found elsewhere in Africa. Differences in rate of spread of HIV infection are probably explained by interplay between numerous factors. The role of different HIV subtypes in the dynamics of the HIV epidemic should be examined further.

Why do men with urethritis in Cameroon prefer to seek care in the informal health sector?

OBJECTIVE

To study the impact of cost of treatment for sexually transmitted diseases (STDs) on the preference of men with urethritis to seek care in the informal sector.

SUBJECTS AND METHODS

A random sample of young men from the general population of Yaoundé and Douala, Cameroon, and of employees of a Yaoundé factory underwent a structured interview on the occurrence of STD-related complaints and health seeking behaviour. Men who consulted in the formal sector were compared with men consulting in the informal sector, with regards to cost of medication and level of education.

RESULTS

Sixteen percent of men in the general population and 20% of factory employees reported a history of urethritis in the 12 months preceding the interview. Of the men in the general population 53% had sought care in the formal sector; among the factory employees this proportion was 56%. Men who did not consult in the formal sector spent significantly less on drugs than men who did consult in the formal sector: median cost $14.4 versus $24.0 (p = 0.02) for drugs purchased in pharmacies; median cost $8 versus $32 for drugs purchased in small stores or from acquaintances. Preference for formal health services was associated with higher educational attainment.

CONCLUSION

In large towns in Cameroon the utilisation of formal health services for STD related complaints is low and the high cost of treatment in the formal sector may play an important role in the choice of care option.

Benefits of HIV screening of blood transfusions in Zambia

Blood transfusion continues to be an important route of transmission of HIV in developing countries, especially for young children following the perinatal period. Testing for HIV is costly and reliable donor support for the purchase of test kits is often essential, yet difficult to secure. The costs of screening transfusions for HIV and the financial benefits in terms of savings on treatment costs averted were calculated for a district hospital in Zambia where seroprevalence among donors was 15.9%. Financial benefits exceed costs by a factor of 2.7-3.5. In 1991, 1073 transfusions were given and an estimated 150 cases of transfusion-related AIDS were prevented by screening, of which 59% were in children aged 5 years or under and 31% were in women. The total cost of HIV screening was 3061 pounds ($4745), and the cost per case of HIV infection prevented was 20.40 pounds ($31.62); the cost of this protection for the population served by the hospital was 0.02 pounds ($0.03) per person. An estimated 3625 undiscounted healthy years of life were saved, of which nearly 69% were in children under 6, at a cost of 0.85 pounds ($1.32) per year of life saved. It is essential that financial and political support for HIV screening of blood for transfusion is maintained.

HTLV-I infection among prostitutes and pregnant women in Kinshasa, Zaïre: how important is high-risk sexual behavior?

High-risk sexual behavior as risk factor for human T-cell lymphotropic virus type I (HTLV-I) infection was assessed in cross-sectional studies with 1,183 prostitutes and 1,166 pregnant women in Kinshasa, Zaire. Eighty six (7.3%) prostitutes were positive for HTLV-I. The seroprevalence among prostitutes from the regions along the equator was 12.7%, whereas among prostitutes from the other regions it ranged between 0 and 4.3%. In the prostitutes from the high-prevalence regions, but not in the prostitutes from the low-prevalence regions, HTLV-I infection was associated with increasing age [odds ratio (OR) = 1.1 per year increment], active syphilis (OR = 2.3), and human immunodeficiency virus (HIV) infection (OR = 2.0). Forty three (3.7%) pregnant women were HTLV-I seropositive. Among the women from low-prevalence regions, there was no significant difference in HTLV-I seroprevalence between prostitutes (4.3%) and pregnant women (3.5%). In a group of 409 prostitutes who were observed for a mean duration of 23 months, the incidence of HTLV-I infection was 0.7 per 100 women-years, whereas the incidence of HIV infection was 9.8 per 100 women-years. We conclude that in Kinshasa prostitution per se was not associated with an increased risk of HTLV-I infection.