Placental infection by Zika virus in French Guiana.

OBJECTIVES: To describe placental findings on prenatal ultrasound and anatomopathological examination in women with Zika virus (ZIKV) infection, and to assess their association with congenital ZIKV infection and severe adverse outcome, defined as fetal loss or congenital Zika syndrome (CZS). METHODS: This was a prospective study of pregnancies undergoing testing for maternal ZIKV infection at a center in French Guiana during the ZIKV epidemic. In ZIKV-positive women, congenital infection was defined as either a positive reverse transcription polymerase chain reaction result or identification of ZIKV-specific immunoglobulin-M in at least one placental, fetal or neonatal sample. Placental ZIKV-infection status was classified as non-exposed (placentae from non-infected women), exposed (placentae from ZIKV-infected women without congenital infection) or infected (placentae from ZIKV-infected women with proven congenital infection). Placentae were assessed by monthly prenatal ultrasound examinations, measuring placental thickness and umbilical artery Doppler parameters, and by anatomopathological examination after live birth or intrauterine death in women with ZIKV infection. The association of placental thickness during pregnancy and anatomopathological findings with the ZIKV status of the placenta was assessed. The association between placental findings and severe adverse outcome (CZS or fetal loss) in the infected group was also assessed. RESULTS: Among 291 fetuses/neonates/placentae from women with proven ZIKV infection, congenital infection was confirmed in 76 cases, of which 16 resulted in CZS and 11 resulted in fetal loss. The 215 remaining placentae from ZIKV-positive women without evidence of congenital ZIKV infection represented the exposed group. A total of 334 placentae from ZIKV-negative pregnant women represented the non-exposed control group. Placentomegaly (placental thickness > 40 mm) was observed more frequently in infected placentae (39.5%) than in exposed placentae (17.2%) or controls (7.2%), even when adjusting for gestational age at diagnosis and comorbidities (adjusted hazard ratio (aHR), 2.02 (95% CI, 1.22-3.36) and aHR, 3.23 (95% CI, 1.86-5.61), respectively), and appeared earlier in infected placentae. In the infected group, placentomegaly was observed more frequently in cases of CZS (62.5%) or fetal loss (45.5%) than in those with asymptomatic congenital infection (30.6%) (aHR, 5.43 (95% CI, 2.17-13.56) and aHR, 4.95 (95% CI, 1.65-14.83), respectively). Abnormal umbilical artery Doppler was observed more frequently in cases of congenital infection resulting in fetal loss than in those with asymptomatic congenital infection (30.0% vs 6.1%; adjusted relative risk (aRR), 4.83 (95% CI, 1.09-20.64)). Infected placentae also exhibited a higher risk for any pathological anomaly than did exposed placentae (62.8% vs 21.6%; aRR, 2.60 (95% CI, 1.40-4.83)). CONCLUSIONS: Early placentomegaly may represent the first sign of congenital infection in ZIKV-infected women, and should prompt enhanced follow-up of these pregnancies. Copyright © 2019 ISUOG. Published by John Wiley & Sons Ltd.

The burden of hepatitis C virus in Cameroon: Spatial epidemiology and historical perspective.

Cameroon is thought to have one of the highest prevalences of hepatitis C virus (HCV) infection in the world (4.9% among adults). A marked cohort effect exists in several communities where ≈50% of the elderly are infected. Better assessment of HCV distribution is needed for planning treatment programmes. We tested for HCV antibodies 14 150 capillary blood samples collected during the 2011 Demographic and Health Survey, whose participants were representative of the Cameroonian population aged 15-49 (both genders) and 50-59 years (men only). Historical data on exposure to medical care were collected and factors associated with HCV assessed through logistic regression and geospatial analyses. To estimate prevalence in all persons aged ≥15 years, we used data from the survey for the 15-59 years fraction and modelled a cohort effect for older individuals. The nationwide HCV prevalence was 0.81% for the 15-49 years group, and 2.51% for all individuals aged ≥15 years. Only 0.2% of individuals aged 15-19 were seropositive. Among participants aged 15-44 years, HCV was associated with age, rural residence and, for males, with ritual circumcision. For those aged 45-59 years, HCV was associated with age and access to medical care in the late 1950s. Prevalence of HCV seropositivity in Cameroon is half of previous estimates. Nationwide surveys are essential to rationalize resources allocation. The high prevalence among older cohorts, a colonial legacy, has had little spillover into younger cohorts. HCV-free generations might be attainable in countries not plagued with intravenous drug abuse.

Increased recurrence rates of hepatocellular carcinoma after DAA therapy in a hepatitis C-infected Egyptian cohort: A comparative analysis.

In Egypt, hepatocellular carcinoma (HCC) is the most common form of cancer and direct-acting antivirals (DAA) are administered on a large scale to patients with chronic HCV infection to reduce the risk. In this unique setting, we aimed to determine the association of DAA exposure with early-phase HCC recurrence in patients with a history of HCV-related liver cancer. This was a prospective cohort study of an HCV-infected population from one Egyptian specialized HCC management centre starting from the time of successful HCC intervention. The incidence rates of HCC recurrence between DAA-exposed and nonexposed patients were compared, starting from date of HCC complete radiological response and censoring after 2 years. DAA exposure was treated as time varying. Two Poisson regressions models were used to control for potential differences in the exposed and nonexposed group; multivariable adjustment and balancing using inverse probability of treatment weighting (IPTW). We included 116 patients: 53 treated with DAAs and 63 not treated with DAAs. There was 37.7% and 25.4% recurrence in each group after a median of 16.0 and 23.0 months of follow-up, respectively. Poisson regression using IPTW demonstrated an association between DAAs and HCC recurrence with an incidence rate ratio of 3.83 (95% CI: 2.02-7.25), which was similar in the multivariable-adjusted model and various sensitivity analyses. These results add important evidence towards the possible role of DAAs in HCC recurrence and stress the need for further mechanistic studies and clinical trials to accurately confirm this role and to identify patient characteristics that may be associated with this event.

Hepatitis C virus seroprevalence in adults in Africa: a systematic review and meta-analysis.

With the introduction of more efficient treatments for hepatitis C virus (HCV), improved epidemiological information is required at the country level to allow evidence-based policymaking for elaboration of national strategies and HCV resources planning. We present a systematic review with meta-analysis of HCV seroprevalence data in adults in African countries. We conducted a systematic review of all HCV seroprevalence estimates reported in African countries from 2000 to 2014 in MEDLINE, AJOL and grey literature. We assessed studies performed in the general population and among blood donors, pregnant women and HIV-positive patients. A meta-regression analysis was used to provide adjusted estimates of HCV seroprevalence in the general adult population in each country, accounting for the heterogeneity in sample age structure and population types in the included studies. We identified 775 national-level estimations, among which 184 were included. Estimates of HCV seroprevalence were produced for 38 countries, in addition to the results from nationwide representative surveys available in Egypt and Libya. Next to Egypt, which clearly stands out, the highest levels of seroprevalence were found in Middle Africa (e.g. Cameroon, Gabon and Angola) and some West African countries (e.g. Burkina Faso, Benin), and the largest absolute numbers of infected adults were found in Nigeria, Ethiopia and Democratic Republic of Congo. This study exposes the diversity of HCV epidemiology among African countries. Egypt and several countries of West and Middle Africa present a HCV burden that will require strong governmental commitment to promote efficient preventive and curative interventions.

Comparison of liver biopsy and noninvasive techniques for liver fibrosis assessment in patients infected with HCV-genotype 4 in Egypt.

In Egypt, as elsewhere, liver biopsy (LB) remains the gold standard to assess liver fibrosis in chronic hepatitis C (CHC) and is required to decide whether a treatment should be proposed. Many of its disadvantages have led to develop noninvasive methods to replace LB. These new methods should be evaluated in Egypt, where circulating virus genotype 4 (G4), increased body mass index and co-infection with schistosomiasis may interfere with liver fibrosis assessment. Egyptian CHC-infected patients with G4 underwent a LB, an elastometry measurement (Fibroscan(©)), and serum markers (APRI, Fib4 and Fibrotest(©)). Patients had to have a LB ≥15 mm length or ≥10 portal tracts with two pathologists blinded readings to be included in the analysis. Patients with hepatitis B virus co-infection were excluded. Three hundred and twelve patients are reported. The performance of each technique for distinguishing F0F1 vs F2F3F4 was compared. The area under receiver operating characteristic curves was 0.70, 0.76, 0.71 and 0.75 for APRI, Fib-4, Fibrotest© and Fibroscan©, respectively (no influence of schistosomiasis was noticed). An algorithm using the Fib4 for identifying patients with F2 stage or more reduced by nearly 90% the number of liver biopsies. Our results demonstrated that noninvasive techniques were feasible in Egypt, for CHC G4-infected patients. Because of its validity and its easiness to perform, we believe that Fib4 may be used to assess the F2 threshold, which decides whether treatment should be proposed or delayed.

Hepatitis C virus infection and risk factors in health-care workers at Ain Shams University Hospitals, Cairo, Egypt.

The objectives of this study were to document the background prevalence and incidence of HCV infection among HCWs in Ain Shams University Hospitals in Cairo and analyse the risk factors for HCV infection. A cross-sectional survey was conducted in 2008 among 1770 HCWs. Anti-HCV prevalence was age-standardized using the Cairo population. A prospective cohort was followed for a period of 18 months to estimate HCV incidence. The crude anti-HCV prevalence was 8.0% and the age-standardized seroprevalence was 8.1%. Risk factors independently associated with HCV seropositivity were: age, manual worker, history of blood transfusions and history of parenteral anti-schistosomiasis treatment. The estimated incidence of HCV infection was 7.3 per 1000 person-years. HCWs in this setting had a similar high HCV seroprevalence as the general population of greater Cairo.

Towards realistic estimates of HCV incidence in Egypt.

Accurate incidence estimates are essential for quantifying hepatitis C virus (HCV) epidemic dynamics and monitoring the effectiveness of public health programmes, as well as for predicting future burden of disease and planning patient care. In Egypt, the country with the largest HCV epidemic worldwide, two modelling studies have estimated age-specific incidence rates that, applied to the age pyramid, would correspond to more than 500 000 Egyptians getting infected annually. This is in contrast to figures of the Egyptian Ministry of Health and Population that estimates new infections to be approximately 100 000 per year. We performed new analyses of nationwide data to examine the modelling assumptions that led to these estimates. Thus, we found that the key assumption of these models of a stationary epidemic is invalid. We propose an alternate approach to estimating incidence based on analysing cohort data; we find that the number of annual new infections is <150 000.

Investigation of a mpox outbreak in Central African Republic, 2021-2022.

Human monkeypox virus is spreading globally, and more information is required about its epidemiological and clinical disease characteristics in endemic countries. We report the investigation of an outbreak in November 2021 in Central African Republic (CAR). The primary case, a hunter, fell ill after contact with a non-human primate at the frontier between forest and savannah. The ensuing investigation in a small nearby town concerned two families and four waves of inter-human transmission, with 14 confirmed cases, 11 suspected cases and 17 non-infected contacts, and a secondary attack rate of 59.5% (25/42). Complications were observed in 12 of the 19 (63.2%) confirmed and suspected cases with available clinical follow-up data: eight cases of bronchopneumonia, two of severe dehydration, one corneal ulcer, one abscess, two cutaneous superinfections, and six cutaneous sequelae (cheloid scars, or depigmentation). There was one death, giving a case fatality ratio of 1/25 (4.0%) for confirmed and suspected cases. This outbreak, with the largest number of confirmed cases ever described in CAR, confirms the potential severity of the disease associated with clade I monkeypox viruses, and highlights the need for rapid control over virus circulation to prevent the further national and international spread of infection.

HCV burden of infection in Egypt: results from a nationwide survey.

Egypt is the country with the largest hepatitis C virus (HCV) epidemic in the world. In 2008, a Demographic Health Survey (DHS) was carried out in Egypt, providing for the first time a unique opportunity for HCV antibody testing on a nationwide representative sample of individuals. Consenting individuals answered a questionnaire on socio-demographic characteristics and iatrogenic exposures, before providing a blood sample for HCV antibody testing by enzyme-linked immunosorbent assay. Factors independently associated with HCV infection were examined through multivariate logistic regression models. Of 12 780 eligible subjects aged 15-59 years, 11 126 (87.1%) agreed to participate and provided a blood sample. HCV antibody prevalence nationwide was 14.7% (95% CI 13.9-15.5%) in this age group. HCV antibody prevalence gradually increased with age, reaching, in the 50-59 years age group, 46.3% and 30.8% in males and females, respectively. It was higher in males compared to females (17.4% versus 12.2%, respectively, P < 0.001), and in rural compared to urban areas (18.3% versus 10.3%, respectively, P < 0.001). In multivariate analysis, age, male sex, poverty, past history of intravenous anti-schistosomiasis treatment, blood transfusion, and living outside of the Frontier Governorates were all significantly associated with an increased risk of HCV infection. In addition, in urban areas, lack of education and being circumcised for females were associated with an increased risk of HCV infection. This study confirmed on a nationwide representative sample the very high HCV antibody prevalence in Egypt. It stresses the urgent need for strengthening prevention efforts, and bringing down the costs of antiviral drugs for countries like Egypt, where the people in the most precarious situations are also those most likely to be infected by the virus.

Reproducibility of liver stiffness measurements in hepatitis C virus (HCV)-infected patients in Egypt.

Elastometry has demonstrated good accuracy, but little is known about its reproducibility. The aim of this study was to assess the intra- and inter-operator reproducibility of liver stiffness measurement among hepatitis C virus (HCV)-infected patients in Egypt. The study was conducted among HCV-infected patients referred for treatment evaluation in two hepatitis treatment centres of Cairo. Two operators took liver stiffness measurement two times per patient the same day. Intra- and inter-reproducibility were estimated by different methods: Bland and Altman graphics, variation coefficient, intraclass correlation coefficient and Kappa coefficient; 7.1 kPa was used as the threshold of significant (≥F2) fibrosis whenever needed. Fifty-eight patients were included in the study, and 216 measurements were taken. Failure rate was 7% and associated with overweight. For a value of 7.1 kPa, the inter-operator 95% limits of agreement were estimated at ±2.88 kPa. Intra- and inter-operator coefficients of variation ranged between 11% and 15%, intraclass correlation coefficients [95% confidence interval] between 0.94 [0.86-0.97] and 0.97 [0.95-0.99], and Kappa coefficients between 0.65 [0.44-0.88] and 0.92 [0.81-1.00]. The reliability of liver stiffness measurement is questionable when considering the decision to initiate antiviral therapy because of the percentage of discordance between measurements is notable, especially in the intermediate fibrosis stages.

Predictive factors of severe disease secondary to falciparum malaria among travelers.

OBJECTIVES: To identify independent risk factors of severe falciparum malaria among travelers to endemic regions. MATERIALS AND METHODS: A retrospective study on imported malaria into metropolitan France. The World's Health Organization severity criteria were used to classify malarial episodes. RESULTS: Nine hundred and twenty-one malarial cases were studied; 81 were severe. Independent risk factors of severe malaria were aged above 40 years, high level of parasitized erythrocytes (more than 4%), parasite acquisition in the south-eastern asian region, infection with a chloroquine resistant Plasmodium falciparum (P. falciparum) phenotype and a self administered antimalarial treatment. CONCLUSION: This study points out two particularly interesting results: severe malaria is significantly associated with the infection by a chloroquine resistant P. falciparum phenotype and with the parasite's acquisition in the south-eastern asian region.

HCV iatrogenic and intrafamilial transmission in Greater Cairo, Egypt.

OBJECTIVES: To document hepatitis C virus (HCV) intrafamilial transmission and assess its relative importance in comparison to other current modes of transmission in the country with the largest HCV epidemic in the world. HCV intrafamilial transmission was defined as HCV transmission among relatives living in the same household. DESIGN: Case-control study. Cases were adult patients with acute hepatitis C diagnosed in two 'fever hospitals' of Cairo. Controls were adult patients with acute hepatitis A diagnosed in the same two hospitals, and family members of cases. All consenting household members of cases provided blood for HCV serological and RNA testing. Homology of viral sequences (NS5b region) within households was used to ascertain HCV intrafamilial transmission. Exposures at risk for HCV during the 1-6 months previous to onset of symptoms were assessed in all cases and controls. RESULTS: From April 2002 to June 2007, 100 cases with acute hepatitis C, and 678 controls (416 household members and 262 patients with acute hepatitis A) were recruited in the study. Factors independently associated with HCV infection and their attributable fractions (AFs) were the following: having had a catheter (OR=5.0, 95% CI=1.4 to 17.8; AF=6.7%), an intravenous perfusion (OR=5.8, 95% CI=2.5 to 13.3; AF=20.1%), stitches (OR=2.0, 95% CI=1.3 to 6.6; AF=10.7%), gum treatment (OR=3.7, 95% CI=1.1 to 11.9; AF=3.8%) and being illiterate (OR=2.4, 95% CI=1.4 to 4.4). Of the 100 cases, 18 had viraemic HCV-infected household members. Three long-married (>15 years) couples were infected with virtually identical sequences and none of the three index patients reported any exposure at risk, suggesting HCV intra-familial transmission. CONCLUSION: While three new HCV infections out of 100 could be linked to intra-familial transmission, parenteral iatrogenic transmission (dental care included) was accountable for 34.6% of these new infections. Thus, the relative contribution of intrafamilial transmission to HCV spread seems to be limited.

Dissection of familial correlations in hepatitis C virus (HCV) seroprevalence suggests intrafamilial viral transmission and genetic predisposition to infection.

OBJECTIVE: Unsafe injections and transfusions used during treatments are considered to be responsible for many cases of transmission of hepatitis C virus (HCV) in developing countries, but cannot account for a substantial proportion of present infections. The aim of the present work was to investigate familial clustering of HCV infection in a population living in a highly endemic area. DESIGN, SETTING AND PARTICIPANTS: A large seroepidemiological survey was conducted on 3994 subjects (age range, 2-88 years) from 475 familial clusters in an Egyptian rural area. Epidemiological methods appropriate for the analysis of correlated data were used to estimate risk factors and familial dependences for HCV infection. A phylogenetic analysis was conducted to investigate HCV strain similarities within and among families. MAIN OUTCOME MEASURES: HCV familial correlations adjusted for known risk factors, similarities between viral strains. RESULTS: Overall HCV seroprevalence was 12.3%, increasing with age. After adjustment for relevant risk factors, highly significant intrafamilial resemblances in HCV seroprevalence were obtained between father-offspring (odds ratio (OR) = 3.4 (95% confidence interval (CI), 1.8 to 6.2)), mother-offspring (OR = 3.8 (95% CI, 2.5 to 5.8)), and sibling-sibling (OR = 9.3 (95% CI, 4.9 to 17.6)), while a weaker dependence between spouses (OR = 2.2 (95% CI, 1.3 to 3.7)) was observed. Phylogenetic analysis showed greater HCV strain similarity between family members than between unrelated subjects, indicating that correlations can be explained, in part, by familial sources of virus transmission. In addition, refined dissection of correlations between first-degree relatives supported the role of host genes predisposing to HCV infection. CONCLUSIONS: Current HCV infection in endemic countries has a strong familial component explained, at least partly, by specific modes of intrafamilial viral transmission and by genetic predisposition to infection.

Efficacy of chloroquine-proguanil malaria prophylaxis in a non-immune population in Bangui, Central African Republic: a case-control study.

A case-control study was conducted to evaluate the efficacy of the combination of chloroquine plus proguanil as malaria prophylaxis in a non-immune population living in the Central African Republic. Cases were patients presenting with a malaria attack confirmed by a positive blood film and/or an HRP2 positive antigen test at the Pasteur Institute of Bangui. Two control subjects were included per case: one was a relative or close friend and the other was matched to the patient with respect to the length of stay. A questionnaire assessing malaria prophylaxis habits and malarial risk factors over the 2-month period prior to inclusion in the study was given to 48 cases and 96 controls. A conditional logistic regression was used to identify risk factors. The efficacy of the chloroquine plus proguanil regimen was found to be high (95.5%, 95% CI 74.0-99.2%) in this country known for high chloroquine resistance. Our data lend some support to the use of chloroquine plus proguanil in Bangui, and the protective efficacy of chloroquine plus proguanil should now be studied prospectively as part of a randomised controlled trial of various prophylactic drugs.

Sexual behaviours, perception of risk of HIV infection, and factors associated with attending HIV post-test counselling in Ethiopia.

OBJECTIVES: To describe sexual behaviours, perception of risk of HIV infection, and factors associated with attending HIV post-test counselling (PTC) among Ethiopian adults. METHODS: Data on socio-demographic characteristics, knowledge of HIV infection, sexual history, medical examination, and HIV and syphilis serological status were compared, through uni- and multivariate analysis, in relation to attending PTC within 60 days of HIV testing. RESULTS: Between February 1997 and June 1998, 751 factory workers were enrolled in a cohort study of HIV infection progression. Despite reporting high-risk sexual behaviours, mainly for males (64% of males and 6% of females had more than five sexual partners in their lifetime, 16% of males and 2% of females reported having had recent casual partners), and knowing that HIV is commonly transmitted heterosexually in Ethiopia (97% of answers being correct, both genders combined), only 17% of males and 2% of females acknowledged having had activities which had put them at risk of HIV infection. HIV prevalence was 12%, and did not differ by gender. Of all study participants, 327 (43.5%) returned for PTC within 60 days of HIV testing. PTC attendance did not differ by age, gender, or HIV serological status. Factors independently associated with PTC attendance in males were: good knowledge of HIV infection, [odds ratio (OR) = 1.661, belief that medical follow-up improves the course of HIV infection (OR = 2.02), history of genital symptoms (OR = 2.83), positive syphilis serology (OR = 2.62), recent weight loss (OR = 1.89), and, with a negative association, being a manual worker (OR = 0.40), and history of recent casual sexual relationships (OR = 0.35). In women, belief that HIV/AIDS can be cured (OR = 3.16), never having been married (OR = 5.02), having five or less children (OR = 2.16), having been raped (OR = 3.42), and having used health facilities in the past year (OR = 1.73) were all positively and independently associated with PTC attendance. CONCLUSION: Study participants reported high-risk sexual behaviours, yet had a low perception of individual risk. Men attended for PTC because of their knowledge of HIV infection, their past sexual history or their current health status. Women attended for PTC because of their plans for the future, marriage and/or children, rather than their past sexual exposure. Only in cases of rape were they willing to learn of their HIV status.

Protection against sexually transmitted diseases by granting sex workers in Thailand the choice of using the male or female condom: results from a randomized controlled trial.

BACKGROUND: The male condom is the most effective barrier method available for protection against sexually transmitted diseases (STDs), including HIV infection. There is an urgent need to develop and evaluate other prevention methods, such as the female condom. This study estimated the additional protection against STDs offered to sex workers by giving them the option of using the female condom when clients refused to use a male condom. METHODS: Sex establishments in four cities in Thailand were randomized into two study groups: one in which sex workers were instructed to use male condoms consistently (male condom group); and one in which sex workers had the option of using the female condom if clients refused or were not able to use male condoms (male/female condom group). Randomization was done by sex establishments, and not by individuals, to minimize sharing of female condoms across study groups. The proportion of unprotected sexual acts (defined as sexual acts in which condoms were not used, tore, or slipped in or out) and incidence rate of STDs (gonorrhoea, chlamydial infection, trichomoniasis and genital ulcer disease) were measured over a 24-week period and compared between the two study groups. FINDINGS: Results are available from 34 sex establishments (249 women) in the male/female condom group, and 37 sex establishments (255 women) in the male condom group. Condom use was very high in both groups (97.9 and 97.3 % of all sexual acts, respectively, P > 0.05). Male condom use was lower in the male/female condom group when compared with the male condom group (88.2 and 97.5%, respectively, P < 0.001). However, this reduction in male condom use was counterbalanced by the use of female condoms in 12.0% of all sexual acts in the male/female condom group, contributing to a 17% reduction in the proportion of unprotected sexual acts in this group when compared to the male condom group (5.9 versus 7.1%, respectively, P = 0.16). Female condom use was sustained over the entire study period. There was also a 24% reduction in the weighted geometric mean incidence rate of STDs in the sex establishments of the male/female condom group compared to the male condom group (2.81 versus 3.69 per 100 person-weeks, P = 0.18).

HIV-1 subtype C syncytium- and non-syncytium-inducing phenotypes and coreceptor usage among Ethiopian patients with AIDS.

OBJECTIVE: To assess syncytium-inducing (SI) and non-syncytium-inducing (NSI) frequencies, coreceptor usage and gp120 V3 sequences of HIV-1 isolates from Ethiopian AIDS patients. PATIENTS: Cross-sectional study on 48 hospitalized AIDS patients (CD4 T cells < 200 x 10(6) cell/l) with stage III or IV of the WHO staging system for HIV-1 infection and disease. METHODS: Peripheral blood mononuclear cells (PBMC) from all 48 patients were tested by MT-2 assay to determine SI/NSI phenotypes. Lymphocyte subsets were enumerated using Coulter counting and FACScan analysis. Viral load determination used a nucleic acid sequence-based amplification assay (NASBA). Coreceptor usage of HIV-1 biological clones was measured using U87 CD4/chemokine receptor transfectants and phytohemagglutinin-stimulated PBMC of healthy donors with wild-type CCR5 and homozygous mutation CCR5delta32 (a 32 base-pair deletion in CCR5). Reverse transcriptase polymerase chain reaction sequencing was performed on the third variable region (V3) of the HIV-1 gene gp120. Sequence alignments were done manually; phylogenetic analyses used PHYLIP software packages. RESULTS: SI viruses were detected for 3/48 (6%) AIDS patients only. Lower mean absolute CD4 counts were determined in patients with SI virus compared with NSI (P = 0.04), but no differences in viral load were observed. All patients were found to be infected with HIV-1 subtype C, based on V3 sequencing. NSI biological clones used CCR5 as coreceptor; SI biological clones used CXCR4 and/or CCR5 and/or CCR3. CONCLUSIONS: Ethiopian patients with HIV-1 C-subtype AIDS harbour a remarkably low frequency of SI phenotype viruses. Coreceptor usage of these viruses correlates with their biological phenotypes.

Factors associated with HIV-1 infection among sex workers of Addis Ababa, Ethiopia.

OBJECTIVE: To study the prevalence and risk factors for HIV infection among sex workers of Addis Ababa, Ethiopia. DESIGN AND METHODS: Cross-sectional survey on socio-demographic characteristics, behaviours, and HIV serological status of sex workers attending two health centres of Addis Ababa. RESULTS: HIV prevalence among sex workers was 274 of 372 (73.7%). Several factors were significantly associated with an increased risk of being HIV-infected [among others, working in 'shared rooms', high number of clients, use of injectable hormones, and positive Treponema pallidum particle agglutination (TPPA) serology], and others with a decreased risk (being born in Addis Ababa, high level of education, peer education on sex work, condom use, use of oral pill, and use of condoms for contraception). Of interest, sex workers who were using condoms for contraception were, compared with others, more likely to use condoms consistently (65 versus 24%, respectively; P < 0.001), and less likely to be HIV-infected (55 versus 86%, respectively; P < 0.001). In multivariate analysis [log-binomial model, giving estimates of the prevalence ratio (PR)], being born in Addis Ababa (PR = 0.74; 95% confidence interval (CI), 0.61-0.91), using condoms for contraception (PR = 0.73; 95% CI, 0.64-0.85), and a positive TPPA serology (PR = 1.21; 95% CI, 1.09-1.36), remained significantly associated with HIV infection. CONCLUSIONS: HIV prevalence was remarkably high among sex workers of Addis Ababa. Condom use was higher, and HIV prevalence lower, in sex workers using condoms not only for prevention of HIV and sexually transmitted diseases, but also for contraceptive purpose. This finding is of particular interest for its implications for prevention strategies among sex workers in the developing world.