Monitoring HIV Drug Resistance: Early Warning Indicators to Assess Performance of Thailand's Antiretroviral Treatment Program

OBJECTIVE

To describe trends in Thailand's antiretroviral treatment (ART) program performance assessed by HIV drug resistance early warning indicators (EWIs), as recommended by WHO, between 2009 and 2013.

MATERIAL AND METHOD

Seven EWIs were monitored, viral load (VL) testing coverage, VL suppression, retention in ART, lost to follow-up (LTFU), antiretrovirals (ARVs) dispensing practices, on-time pill pick-up, and pharmacy stock-outs. Data from ART adult patients in National Health Security Office Scheme were analyzed except for pharmacy stock-outs, which were reported from hospitals. Aggregated averages were calculated for each EWI. Chi-square for trend was applied to measure significant changes.

RESULTS

By September 2013, 174,284 adults were receiving ART at 929 hospitals. Over time, improvement in VL testing coverage (53.8% in 2009 to 79.8% in 2013) was observed. VL suppression and on-time pill pick up rates were well above 90%. Rates of retention in ART declined from 84.0 to 82.9%, whereas LTFU rates increased from 8.3 to 9.2% (p<0.001). Prescriptions with inappropriate ARVs decreased from 0.32 to 0.10% (p<0.001). Of reporting hospitals, 96.1%, 96.3%, and 96.2% observed no ARVs stock-out between 2011 and 2013.

CONCLUSION

EWI is a useful tool to monitor ART program performance and to identify area where improvement is needed.

Risk factors early in the 2010 cholera epidemic, Haiti

During the early weeks of the cholera outbreak that began in Haiti in October 2010, we conducted a case-control study to identify risk factors. Drinking treated water was strongly protective against illness. Our results highlight the effectiveness of safe water in cholera control.

Considerations for oral cholera vaccine use during outbreak after earthquake in Haiti, 2010-2011

Oral cholera vaccines (OCVs) have been recommended in cholera-endemic settings and preemptively during outbreaks and complex emergencies. However, experience and guidelines for reactive use after an outbreak has started are limited. In 2010, after over a century without epidemic cholera, an outbreak was reported in Haiti after an earthquake. As intensive nonvaccine cholera control measures were initiated, the feasibility of OCV use was considered. We reviewed OCV characteristics and recommendations for their use and assessed global vaccine availability and capacity to implement a vaccination campaign. Real-time modeling was conducted to estimate vaccine impact. Ultimately, cholera vaccination was not implemented because of limited vaccine availability, complex logistical and operational challenges of a multidose regimen, and obstacles to conducting a campaign in a setting with population displacement and civil unrest. Use of OCVs is an option for cholera control; guidelines for their appropriate use in epidemic and emergency settings are urgently needed.

Rapid assessment of cholera-related deaths, Artibonite Department, Haiti, 2010

We evaluated a high (6%) cholera case-fatality rate in Haiti. Of 39 community decedents, only 23% consumed oral rehydration salts at home, and 59% did not seek care, whereas 54% of 48 health facility decedents died after overnight admission. Early in the cholera epidemic, care was inadequate or nonexistent.

Prevalence of transmitted HIV drug resistance in Botswana: lessons learned from the HIVDR-Threshold Survey conducted among women presenting for routine antenatal care as part of the 2007 national sentinel survey

The emergence and spread of transmitted drug resistance (TDR) poses a major threat to the success of the rapidly expanding antiretroviral treatment (ART) programs in resource-limited countries. The World Health Organization recommends the use of the HIV Drug Resistance Threshold Survey (HIVDR-TS) as an affordable means to monitor the presence of TDR in these settings. We report our experiences and results of the 2007 HIVDR-TS in Botswana, a country with one of the longest-existing national public ART programs in Africa. The HIVDR-TS and HIV-1 incidence testing were performed in the two largest national sites as part of the 2007 antenatal Botswana Sentinel Survey. The HIVDR-TS showed no significant drug resistance mutations (TDR less than 5%) in one site. TDR prevalence, however, could not be ascertained at the second site due to low sample size. The agreement between HIVDR-TS eligibility criteria and laboratory-based methodologies (i.e., BED-CEIA and LS-EIA) in identifying recently HIV-1 infected adults was poor. Five years following the establishment of Botswana's public ART program, the prevalence of TDR remains low. The HIVDR-TS methodology has limitations for low-density populations as in Botswana, where the majority of antenatal sites are too small to recruit sufficient numbers of patients. In addition, the eligibility criteria (age <25 years and parity (first pregnancy)) of the HIVDR-TS performed poorly in identifying recent HIV-1 infections in Botswana. An alternative sampling strategy should be considered for the surveillance of HIVDR in Botswana and similar geographic settings.

Validation of AIDS-related mortality in Botswana

BACKGROUND

Mortality data are used to conduct disease surveillance, describe health status and inform planning processes for health service provision and resource allocation. In many countries, HIV- and AIDS-related deaths are believed to be under-reported in government statistics.

METHODS

To estimate the extent of under-reporting of HIV- and AIDS-related deaths in Botswana, we conducted a retrospective study of a sample of deaths reported in the government vital registration database from eight hospitals, where more than 40% of deaths in the country in 2005 occurred. We used the consensus of three physicians conducting independent reviews of medical records as the gold standard comparison. We examined the sensitivity, specificity and other validity statistics.

RESULTS

Of the 5276 deaths registered in the eight hospitals, 29% were HIV- and AIDS-related. The percentage of HIV- and AIDS-related deaths confirmed by physician consensus (positive predictive value) was 95.4%; however, the percentage of non-HIV- and non-AIDS-related deaths confirmed (negative predictive value) was only 69.1%. The sensitivity and specificity of the vital registration system was 55.7% and 97.3%, respectively. After correcting for misclassification, the percentage of HIV- and AIDS--related deaths was estimated to be in the range of 48.8% to 54.4%, depending on the definition.

CONCLUSION

Improvements in hospitals and within government offices are necessary to strengthen the vital registration system. These should include such strategies as training physicians and coders in accurate reporting and recording of death statistics, implementing continuous quality assurance methods, and working with the government to underscore the importance of using mortality statistics in future evidence-based planning.

Entertainment-education radio serial drama and outcomes related to HIV testing in Botswana

Makgabaneng is an entertainment-education radio serial drama written and produced in Botswana to promote prevention of HIV. This effort is part of the national response to HIV/AIDS. Broadcast of the serial drama began in August 2001, and two new 15-minute episodes air each week. We examined associations between exposure to Makgabaneng and outcomes related to HIV testing, including stigmatizing attitudes, intention to be tested, talking with a partner about testing, and testing for HIV, among 555 sexually active respondents. The four measures of exposure to Makgabaneng were frequency of listening, duration of listening, talking about the program, and attentiveness to and identification with relevant characters. Data were collected approximately 18 months after the drama began airing. We found positive associations between exposure to the program and intermediate outcomes, including lower level of stigmatizing attitudes, stronger intention to have HIV testing, and talking to a partner about testing. Although associations were identified with all four measures of exposure, increased duration of listening was associated with more positive outcomes than the other measures. This finding suggests that longer term exposure to entertainment-education programming may be important for behavior change.

Baseline evaluation of routine HIV testing among tuberculosis patients in Botswana

In January 2004, the government of Botswana introduced a policy of routine, non-compulsory human immunodeficiency virus (HIV) testing to increase testing and access to antiretroviral treatment (ART) for individuals presenting for medical treatment. Before a systematic implementation of the policy, we conducted a cross-sectional survey of tuberculosis (TB) record data from 46 clinics in 10 districts to assess baseline HIV testing rates among TB patients. Recorded HIV results from the facility TB register and TB treatment card were reviewed. Of the 1242 TB patients entered in the register, 47% had a recorded HIV result and 84% of these were co-infected with HIV. TB treatment cards were available for 862 (69%) registered patients. Among the 411 (47%) with test results recorded on the treatment card, 341 (83%) were HIV-infected; of these, 12% were reported to be receiving ART.

"A bull cannot be contained in a single kraal": concurrent sexual partnerships in Botswana

To inform efforts to curb HIV in Botswana, we describe sexual concurrency and related norms and behaviors among a sample of 807 Batswana age 15-49 years who participated in a 2003 population-based survey. Of 546 sexually active respondents, 23% reported ever having a concurrent sexual partnership with any of the last three partners from the last 12 months. Multivariate analysis found that men and youth (age <25 years), and non-religious people were more likely than their respective counterparts to report concurrency. Respondents reporting concurrency were more likely than those not, to have norms that support multiple partnerships and report low self-efficacy to be faithful to one partner. However, a majority of both groups reported believing that fidelity is important and that they would be looked down upon by family and friends if discovered to have multiple partnerships. The findings suggest that concurrency in Botswana is not uncommon, and yet may not be generally acceptable.

Botswana's Tebelopele voluntary HIV counseling and testing network: use and client risk factors for HIV infection, 2000-2004

BACKGROUND

: HIV services, including voluntary counseling and testing (VCT) and antiretroviral (ARV) therapy, expanded rapidly in Botswana from 2000 through 2004.

METHODS

: Client data from Botswana's Tebelopele VCT network were analyzed to describe clients, factors associated with HIV infection, and trends in VCT use.

RESULTS

: Tebelopele provided free, anonymous, same-day HIV tests for 117,234 clients from 2000 through 2004. Before ARV therapy was available, 8.3% of clients sought a test because of illness, and 26.3% were HIV-positive. After ARV therapy became available, 20.1% of clients sought a test because of illness, and 38.8% were HIV-positive. Most VCT clients (82.7%) were unmarried; 89.8% reported no or 1 sexual partner in the last 3 months; and 50.2% of unmarried clients reported always using condoms in the last 3 months. In multivariate analysis, higher educational level, marriage, and always using condoms were associated with a lower risk of HIV. Having only 1 recent sexual partner was associated with less condom use and a higher risk of being HIV-positive for men.

CONCLUSIONS

: VCT has been well accepted in Botswana. Analysis of this data set supports efforts to promote 100% condom use and to emphasize that partner reduction must be combined with condom use and HIV testing to protect against HIV.

Sociodemographic factors associated with participation by HIV-1-positive pregnant women in an intervention to prevent mother-to-child transmission of HIV in Cote d'Ivoire

Many HIV-1-seropositive women in Africa who are offered antiretroviral prophylaxis to prevent mother-to-child transmission (MTCT) of HIV do not begin interventions. Research on barriers to participation has not addressed the possible effects of women's sociocultural and economic circumstances. We examined these factors at an MTCT prevention programme in Abidjan, Cote d'Ivoire. We interviewed two groups of women after they had received HIV-positive test results and had been invited by the programme staff to return for monthly follow-up visits before beginning short-course zidovudine prophylaxis. Participants (n = 30) completed follow-up visits and prophylaxis. Non-participants (n = 27) refused or discontinued follow-up visits and did not begin zidovudine. Fewer non-participants had been born in Cote d'Ivoire (67% vs. 97%) or were Ivorian nationals (48% vs. 77%); they had lived in the country for less time (21 vs. 26 median years). They were less likely to be French-literate (37% vs. 77%), and more of them reported having had Koranic education only (18% vs. 0). They more often reported miscarriages, stillbirths, or infant deaths (69% vs. 33%), and had partners with low-ranked jobs (63% vs. 30%). Our findings suggest that the non-participants were more marginal socioculturally and economically in Ivorian society than participants. Greater attention to mitigating the effects of broader structural factors on women's participation in interventions may increase the effectiveness of MTCT prevention in Africa.

Women's reasons for not participating in follow up visits before starting short course antiretroviral prophylaxis for prevention of mother to child transmission of HIV: qualitative interview study

OBJECTIVE

To find out why pregnant women who receive HIV-1 positive test results and are offered short course antiretroviral prophylaxis to prevent transmission of HIV from mother to child do not participate in necessary follow up visits before starting prophylaxis.

DESIGN

Qualitative interview study.

SETTING

A programme aiming to prevent transmission of HIV from mother to child at a public antenatal clinic in Abidjan, Côte d'Ivoire.

PARTICIPANTS

Purposive sample of 27 women who had received HIV-1 positive test results and were invited to return for monthly follow up visits before starting prophylaxis with zidovudine at 36 weeks' gestation, but who had either refused or discontinued the visits. None of the women started prophylaxis.

RESULTS

Most of the women explained their non-participation in follow up visits by referring to negative experiences that they had had while interacting with programme staff or to their views about the programme. Additional reasons concerned their disbelief of HIV positive test results and personal factors.

CONCLUSIONS

Difficulties experienced by women during their contacts with staff working on the prevention programme and negative views that they have about the programme can contribute to their non-participation in prophylaxis. Training and supervision of programme staff may increase the likelihood of positive interactions between staff and clients, thereby facilitating women's participation in preventing transmission of HIV from mother to child. Outreach and mobilisation in communities that are served by prevention programmes may complement these measures at programme level by contributing to increased social support for women's efforts to prevent transmission of HIV from mother to child.

Differences in HIV-2 plasma viral load and immune activation in HIV-1 and HIV-2 dually infected persons and those infected with HIV-2 only in Abidjan, Côte D'Ivoire

OBJECTIVE

To determine whether blood plasma levels of HIV-2 RNA viral loads and immune activation markers differ between persons infected with HIV-2 only and those dually infected with HIV-1 and HIV-2.

METHODS

Between September 1996 and February 2000, we collected, analyzed and compared levels of HIV-2 RNA in plasma and immune activation markers among 52 persons infected with HIV-2 alone and 75 with confirmed dual infection. We also compared viral load and immune activation in patients who were infected with HIV-1 only and those who were dually infected.

RESULTS

When we conducted a CD4 T-cell count-stratified multivariate analysis of HIV-2 viral load, controlling for difference in CD4 T-cell counts, age and sex: at < 200 x 10 CD4 T cells/l, HIV-2 viral load was 2.0 log10 copies/ml lower in dually infected patients than in HIV-2 only patients (P < 0.0001). At CD4 T-cell counts between 200 x 10 and 500 x 10/l, HIV-2 viral load was 0.3 log10 copies/ml lower in dually infected patients (P = 0.45). However, at CD4 T-cells counts > 500 x 10/l, HIV-2 viral load was 0.9 log10 copies/ml higher in dually infected patients (P < 0.0001). Dually infected persons with undetectable HIV-2 viral loads had significantly higher median levels of CD8 T cells expressing CD38 (P < 0.001) and HLA-DR (P = 0.01) than HIV-2 only infected patients.

CONCLUSION

These results suggest that in dual infection, the level of HIV-2 replication depends on the immune status of the patients, with HIV-1 out-replicating HIV-2 as disease progress.

HIV-1 viral load and other risk factors for mother-to-child transmission of HIV-1 in a breast-feeding population in Cote d'Ivoire

Short-course antiretroviral regimens have been evaluated to reduce mother-to-child transmission of HIV in resource-limited settings. This report from Abidjan, Cote d'Ivoire, examines the risk factors for HIV transmission by 1 and 24 months among breast-feeding women. Eligible HIV-1-seropositive pregnant women enrolled in this randomized double-blind clinical trial were randomly assigned to receive either oral zidovudine (ZDV) (n = 126) prophylaxis or placebo (n = 124). Maternal prophylaxis began at 36 weeks of gestation (300 mg ZDV twice daily antepartum and 300 mg every 3 hours intrapartum); there was no neonatal prophylaxis component. The cumulative risk of transmission in the treatment group was 11.9% and 22.1% by 1 and 24 months, respectively. In adjusted analyses, viral load at enrollment was the strongest predictor of transmission (per log increment: odds ratio [OR] = 4.8, 95% confidence interval [CI]: 2.5-9.5 at 1 month; OR = 5.7; 95% CI: 3.1-10.8 at 24 months). Overall, ZDV prophylaxis was not significantly protective for infection at 1 or 24 months. Comparing ZDV with placebo following dichotomization of viral load (<50,000 vs. > or =50,000 copies/mL) at enrollment, however, there was a significant effect of ZDV seen only among those women with a low viral load at enrollment. The substantial risk of transmission despite ZDV prophylaxis, particularly among those with higher viral loads, underscores the need to find more effective regimens appropriate for use in resource-limited settings.

HIV prevalence and risk behavior among clients of female sex workers in Abidjan, Côte d'Ivoire

OBJECTIVE

To assess socio-demographic and behavioural characteristics of clients of female sex workers in Abidjan, and to determine their HIV prevalence and related risk factors.

DESIGN

A cross-sectional study among clients of female sex workers in Abidjan, Côte d'Ivoire.

METHODS

A trained interviewer approached clients leaving the room of a female sex worker and invited them for an interview using a structured questionnaire, and to provide a saliva sample. Saliva was tested for HIV antibodies by the GACELISA assay (Murex, Dartford, UK).

RESULTS

A total of 526 clients agreed to participate, and 423 (80.4%) provided a saliva sample. Reported condom use was very high, 92.7% said they always use condoms and 95.4% reported condom use during the visit preceding the interview. The overall HIV prevalence among the clients who provided a saliva sample was 13.4%. Older age and being married or cohabitating was significantly associated with HIV infection in multivariate analysis.

CONCLUSIONS

HIV prevalence appears to be relatively low, and condom use is high among clients of female sex workers in Abidjan. Existing HIV prevention efforts among female sex workers and among the general population should be sustained and reinforced.

Prevalence of genotypic and phenotypic HIV-1 drug-resistant strains among patients who have rebound in viral load while receiving antiretroviral therapy in the UNAIDS-Drug Access Initiative in Abidjan, Côte d'Ivoire

OBJECTIVE

To determine the prevalence of genotypic and phenotypic antiretroviral (ARV) drug-resistant HIV-1 strains among patients with viral load rebound while receiving ARV therapy in Abidjan, Côte d'Ivoire.

METHODS

Between August 1998 and April 2000, we selected all patients (n = 241) who had received ARV drug therapy for at least 6 months in the UNAIDS-Drug Access Initiative (DAI), in Abidjan. We analyzed for genotypic and phenotypic drug resistance among 97 (40%) of the 241 patients who had a rebound in plasma viral load, defined as an initial decrease of > 0.5 log10 copies/ml followed by a subsequent increase of > 0.25 log10 copies/ml.

RESULTS

Of the viruses isolated from the 97 patients, 86 (88.7%) had usable sequences and 68 (79%) of the 86 patients had genotypic resistance to at least one reverse transcriptase inhibitor (RTI) or protease inhibitor (PI). Resistant mutations were found for zidovudine in 50 (78%) of 64 patients who had received the drug, 11 (68.7%) of 16 patients on lamivudine, for nevirapine in two (2%), for indinavir in one (1%), and for ritonavir in one (1%). Phenotypic resistance to at least one nucleoside RTI was seen in 45 (56%) of the 80 patients tested, to non-nucleoside RTIs in eight (10%), and to PIs in one (1.3%). Multivariate regression analysis showed factors associated with resistance to be initial treatment with dual therapy (P = 0.04) compared with highly active antiretroviral therapy, and maximal initial viral load response (P = 0.006).

CONCLUSION

Our results demonstrate a high prevalence of ARV drug resistance associated with dual ARV therapy. These results indicate the limited role for dual ARV therapy.

Changes in levels of immune activation and reconstitution markers among HIV-1-infected Africans receiving antiretroviral therapy

OBJECTIVE

To describe changes in immune activation and reconstitution markers among HIV-1-infected patients receiving antiretroviral therapy (ART) in Abidjan, Côte d'Ivoire.

METHODS

Between November 1998 and February 2001, we analyzed changes in immune activation and reconstitution markers among 52 patients. Good virologic responders (n = 26) were defined as those who had suppressed and maintained plasma viral load (VL) below the detection limit of the assay for at least 12 months. Poor virologic responders (n = 26) were defined as those with a detectable VL at 6 and 12 months after beginning ART.

RESULTS

Of the 26 good virologic responders, 20 (77%) were on highly active antiretroviral therapy (HAART) compared with one (4%) of the poor responders. Among the 26 good responders, baseline median levels of CD38+CD8+ T cells were elevated, but had decreased significantly at 6 months (P < 0.001) and at 12 months of therapy (P < 0.001). Median levels of HLA-DR+CD8+ T cells also decreased from baseline at 6 months (P < 0.001) and at 12 months of therapy (P < 0.001). Levels of CD62L+CD4+ T cells increased steadily during the 6 and 12 months of therapy and reached levels observed among HIV-negative blood donors (P = 0.07). Among the 26 poor responders, median levels of CD38+CD8+ T cells decreased significantly at 12 months of therapy (P = 0.006), but were higher than levels in blood donors (P = 0.005). Levels of HLA-DR+CD8+ T cells decreased significantly at 12 months of therapy (P < 0.001). Levels of CD62L+CD4+ decreased over time.

CONCLUSION

Our results suggest that HAART can be successfully used in African populations with elevated baseline immune activation markers.

Cellular human immunodeficiency virus (HIV)-protective factors: a comparison of HIV-exposed seronegative female sex workers and female blood donors in Abidjan, Côte d'Ivoire

Cellular factors that may protect against human immunodeficiency virus (HIV) infection were investigated in 27 HIV-exposed seronegative (ESN) female sex workers (FSWs) and 27 HIV-seronegative female blood donors. Compared with blood donors, ESN FSWs had significantly decreased expression levels of C-X-C chemokine receptor 4 (CXCR4), but not of C-C chemokine receptor 5, on both memory (P<.001) and naive (P=.041) CD4(+) T cells. CXCR4 down-regulation was associated with prolonged duration of commercial sex work by ESN FSWs. CD38 expression on CD8(+) T cells was significantly increased among ESN FSWs, compared with that among blood donors (P=.017). There were no differences in HLA-DR and CD62L expression between blood donors and ESN FSWs. Proportions of T cells producing the beta-chemokines RANTES (regulated on activation, normally T cell-expressed and -secreted), macrophage inflammatory protein (MIP)-1alpha, and MIP-1beta or the cytokines interleukin (IL)-2, IL-4, interferon-gamma, and tumor necrosis factor-alpha, were similar in the 2 groups. These data indicate that ESN FSWs differ from HIV-seronegative female blood donors with respect to immunological factors that have no clear protective potential against HIV transmission.

Foodborne disease in our global village: a multinational investigation of an outbreak of Salmonella serotype Enteritidis phage type 4 infection in Puerto Vallarta, Mexico

OBJECTIVES

In late 1996, a multinational investigation was launched following an outbreak of diarrheal illness that caused the disruption of an international scientific conference at a first-class hotel in Puerto Vallarta, Mexico.

METHODS

A questionnaire was mailed to all American and to selected international attendees. Additional copies of the questionnaire were provided for any family members who may have attended the conference. A case was defined as an illness with three or more loose stools during a 24-h period in a conference attendee or accompanying family member, with illness lasting 2 or more days and onset between 6 and 9 November 1996.

RESULTS

Questionnaires were returned by 81% (232/288) of American attendees, 47% (18/38) of selected international attendees, and 25 family members; 30% (83/275) of respondents met the case definition. Ill persons resided in at least seven countries. Salmonella serotype Enteritidis phage type 4 was isolated from stool specimens from patients residing in Canada, the UK, and the USA. Attending a hotel banquet on 6 November was associated with illness; 42% (82/194) of banquet attendees became ill versus 3% (1/37) of non-attendees (relative risk (RR)515.6, 95% confidence interval (CI)52.3-108.9). The only banquet food item associated with illness was chili rellenos; 53% (58/109) of persons who ate chili rellenos were ill versus 22% (12/55) of those who did not (RR52.4, 95% CI51.4-4.1). Chili rellenos ingredients included shelled eggs and cheese; Salmonella was isolated from the leftover cheese but the isolate was not serotyped.

CONCLUSIONS

Salmonella may be a cause of traveler's diarrhea and can result in outbreaks even among travelers who follow routine precautions (i.e. staying in a first-class hotel and eating hot foods). International collaboration in investigating similar outbreaks, including sharing subtyping results, will be necessary for long-term prevention. Global Salm-Surv, an international network of Salmonella reference laboratories coordinated by the World Health Organization, may facilitate such collaboration.

Assessing eosinophil count as a marker of immune activation among human immunodeficiency virus-infected persons in sub-Saharan Africa

In 611 human immunodeficiency virus-infected persons who had not yet begun to receive antiretroviral therapy, we evaluated the linear association between absolute eosinophil count (as a surrogate for immune response to helminthic infection) and CD4+ T cell count, and between absolute eosinophil count and log virus load. Overall, no significant correlations were observed between eosinophil count and CD4+ T cell count, or between eosinophil count and log virus load.

Changes in plasma HIV-1-RNA viral load and CD4 cell counts, and lack of zidovudine resistance among pregnant women receiving short-course zidovudine

OBJECTIVE

To describe changes in HIV-1 plasma viral load (VL) and CD4 cell counts and to assess zidovudine resistance associated with a short course of oral zidovudine during late pregnancy.

METHODS

From April 1996 to February 1998 in Abidjan, Côte d'Ivoire, 280 HIV-1-seropositive women were randomly assigned at 36 weeks' gestation to receive zidovudine (300 mg) or placebo twice a day, and then one tablet every 3 h from the onset of labor until delivery. Blood samples obtained every 2 weeks until delivery, then at 2 and 4 weeks, and 3 or 6 months after delivery were tested from selected women based on duration of therapy for plasma VL and CD4 cell counts, and samples from 20 women in the zidovudine group were tested by DNA sequencing for the presence of zidovudine resistance mutations.

RESULTS

In the zidovudine group, the median reduction in plasma VL (log(10) copies/ml) was -0.48 after 2 weeks (P = 0.02 versus placebo), -0.48 after 4 weeks (P = 0.06), -0.80 after 6 weeks (P = 0.29) of treatment, -0.12 at delivery (P = 0.11), +0.21 at 2 weeks (P = 0.83), +0.17 at 4 weeks (P = 0.69), and +0.21 at 3 months (P = 0.56) postpartum. Median CD4 cell counts were higher in the zidovudine than in the placebo group after 2, 4, and 6 weeks of treatment (P < 0.05). No mutations associated with zidovudine resistance were identified in any of the samples tested.

CONCLUSION

These findings suggest that a short course of zidovudine has no adverse HIV-1 virological consequences for the mother.

Positive association between beta-chemokine-producing T cells and HIV type 1 viral load in HIV-infected subjects in Abidjan, Côte d'Ivoire

The role of beta-chemokines in controlling HIV replication in vivo is still controversial. Therefore, the association between HIV-1 plasma viral load and the capacity of CD4(+) and CD8(+) T cells to produce beta-chemokines was studied in 28 antiretroviral drug-naïve HIV-1-infected female sex workers in Abidjan, Côte d'Ivoire. Percentages of beta-chemokine-positive T cells were measured in peripheral blood mononuclear cells by flow cytometry after intracellular staining for RANTES (regulated on activation, normal T expressed and secreted), macrophage inflammatory protein (MIP)-1alpha, and MIP-1beta. HIV-1-infected subjects had higher percentages of MIP-1alpha- and MIP-1beta-positive CD4(+) and CD8(+) T cells (p < 0.02) and of RANTES-positive CD8(+) T cells (p = 0.054) than uninfected controls. Percentages of RANTES- and MIP-1beta-positive CD8(+) T cells correlated directly with HIV-1 plasma viral load (p < 0.02). Percentages of beta-chemokine-positive CD4(+) and CD8(+) T cells correlated directly with percentages of HLA-DR-positive T cells (p < 0.02) and inversely (except RANTES in CD4(+) T cells) with absolute numbers of CD4(+) T cells (p < 0.05) in peripheral blood. These data indicate that increased percentages of beta-chemokine-producing T cells in HIV-1-infected subjects correlate with disease progression and are a sign of viremia-driven chronic T cell activation.

Is drinking water in Abidjan, Côte d'Ivoire, safe for infant formula?

OBJECTIVE

To survey knowledge, attitudes, and practices regarding water use and infant feeding in the Koumassi District of Abidjan, Côte d'Ivoire, and to evaluate the microbiologic quality of source and stored drinking water.

DESIGN

Random-cluster household survey.

METHODS

We randomly selected 20 clusters, each comprising six households with at least 1 child aged < or =3 years. In each household, we administered a questionnaire and collected source and stored drinking water samples and tested these for chlorine levels and for total coliform and fecal bacteria count ( Escherichia coli ).

RESULTS

Municipal water was used for drinking in 112 (93%) of 120 households, and in 99 (83%), it was stored for later use. By 1 month of age, 97 (90%) of 108 infants given drinking water were given stored water for drinking. In 8 (66%) of 12 households where children were receiving artificial feeding, formula was prepared from municipal water without additional treatment. Stored water had lower levels of free chlorine than source water (median of 0.05 versus 0.2 mg/dl; p <.001), and E. coli was detected in 36 (41%) of 87 stored water samples and 1 (1%) of 108 source water samples ( p <.001).

CONCLUSIONS

In the Koumassi District of Abidjan, where municipal water is widely available and of good quality, drinking water is stored in most households, is often contaminated with E. coli, and is given to children at a young age. If replacement feeding is to be more widely used to prevent postnatal transmission of HIV-1, communities using stored water need interventions to make stored water safer.

Lack of effect of chemokine receptor CCR2b gene polymorphism (64I) on HIV-1 plasma RNA viral load and immune activation among HIV-1 seropositive female workers in Abidjan, Côte d'Ivoire

The prevalence of the CCR2b-V64I mutation among human immunodeficiency virus (HIV)-seropositive and -seronegative female workers and the potential effect of heterozygosity of this mutation on HIV-1 plasma RNA viral load and markers of immune activation were assessed. CCR2b-V64I was detected by polymerase chain reaction, followed by restriction enzymes analysis; plasma viral load was measured by the Amplicor HIV-1 monitor assay and CD4(+) T-cell counts and markers of immune activation by standard three-color FACscan flow cytometry. Of the 260 female workers, 56 (21.5%) were heterozygous for CCR2b-V64I, and 8 (3%) were homozygous. Of the 99 HIV-seronegative female workers, 19 (19.2%) were heterozygous for the CCR2b-V64I mutation compared with 37 (23%) of the 161 HIV-seropositive FSW (P = 0.47). In a univariate analysis of viral load among HIV-seropositive FSW, no difference was noted between those heterozygous for or without the mutation; both groups had plasma viral loads of 5.0 log(10) copies/ml. After controlling for the effects of CD4(+) T-cell counts in a multivariate analysis, no significant difference was observed between the groups in viral load or in markers of immune activation. The data suggest that the presence of the CCR2b mutation has no effect on HIV-1 plasma viral load and markers of immune activation in our study population. The finding that the frequency of this mutation is similar in HIV-seropositive and -seronegative female workers suggests that its presence is not associated with increased risk of HIV infection.

Sensitivity and specificity of human immunodeficiency virus rapid serologic assays and testing algorithms in an antenatal clinic in Abidjan, Ivory Coast

To evaluate serologic testing algorithms for human immunodeficiency virus (HIV) based on a combination of rapid assays among persons with HIV-1 (non-B subtypes) infection, HIV-2 infection, and HIV-1-HIV-2 dual infections in Abidjan, Ivory Coast, a total of 1,216 sera with known HIV serologic status were used to evaluate the sensitivity and specificity of four rapid assays: Determine HIV-1/2, Capillus HIV-1/HIV-2, HIV-SPOT, and Genie II HIV-1/HIV-2. Two serum panels obtained from patients recently infected with HIV-1 subtypes B and non-B were also included. Based on sensitivity and specificity, three of the four rapid assays were evaluated prospectively in parallel (serum samples tested by two simultaneous rapid assays) and serial (serum samples tested by two consecutive rapid assays) testing algorithms. All assays were 100% sensitive, and specificities ranged from 99.4 to 100%. In the prospective evaluation, both the parallel and serial algorithms were 100% sensitive and specific. Our results suggest that rapid assays have high sensitivity and specificity and, when used in parallel or serial testing algorithms, yield results similar to those of enzyme-linked immunosorbent assay-based testing strategies. HIV serodiagnosis based on rapid assays may be a valuable alternative in implementing HIV prevention and surveillance programs in areas where sophisticated laboratories are difficult to establish.

High prevalence of genotypic and phenotypic HIV-1 drug-resistant strains among patients receiving antiretroviral therapy in Abidjan, Côte d'Ivoire

To describe prevalence of antiretroviral (ARV) drug-resistant HIV-1 strains among patients with a history of earlier treatment with ARV drugs in Abidjan, Côte d'Ivoire, we determined mutations that confer HIV-1 ARV drug resistance by sequencing the viral reverse-transcriptase and protease genes derived from plasma viral RNA of 68 individuals consecutively enrolled in the Joint United Nations Program on AIDS Drug Access Initiative (UNAIDS-DAI) with a history of earlier ARV drug treatment in Abidjan between August 1998 and April 1999. Phenotypic ARV drug resistance was assessed using a recombinant virus assay. Primary mutations associated with ARV drug resistance to at least one of the reverse-transcriptase inhibitors or protease inhibitors were detected in 39 (57.4%) of the 68 patients. The prevalence of mutations associated with resistance to ARV drugs was: 29 (42.6%) to zidovudine, 10 (14.7%) to lamivudine, one (1.5%) to didanosine, one K103N mutation (associated with resistance to delavirdine, nevirapine, and efavirenz), one Y181C mutation (associated with resistance to delavirdine and nevirapine), two to both indinavir (M46I/L and V82A) and saquinavir (G48V and L90M), and one each to ritonavir (V82A) and nelfinavir (D30N). Phenotypic resistance to at least one nucleoside reverse transcriptase inhibitor (RTI) was seen in 25 (39.7%) patients, to nonnucleoside RTIs in 5 (8%) patients, and to protease inhibitors in 4 (6%) patients. The high prevalence we observed in this study may limit in future the effectiveness of ARV programs in the Côte d'Ivoire.

The changing epidemiology of salmonella: trends in serotypes isolated from humans in the United States, 1987-1997

Salmonellosis is a major cause of illness in the United States. To highlight recent trends, data for 1987-1997 from the National Salmonella Surveillance System were analyzed. A total of 441,863 Salmonella isolates were reported, with the highest age-specific rate among infants (159/100,000 infants at 2 months). Annual isolation rates decreased from 19 to 13/100,000 persons; however, trends varied by serotype. The isolation rate of Salmonella serotype Enteritidis increased until 1996, whereas declines were noted in Salmonella serotypes Hadar and Heidelberg. Overall, serotypes that increased in frequency were significantly more likely than those that decreased to be associated with reptiles (P=.008). Salmonella infections continue to be an important cause of illness, especially among infants. Recent declines in food-associated serotypes may reflect changes in the meat, poultry, and egg industries that preceded or anticipated the 1996 implementation of pathogen-reduction programs. Additional educational efforts are needed to control the emergence of reptile-associated salmonellosis.

Efficacy of trimethoprim-sulphamethoxazole prophylaxis to decrease morbidity and mortality in HIV-1-infected patients with tuberculosis in Abidjan, Côte d'Ivoire: a randomised controlled trial

BACKGROUND

There is a high incidence of opportunistic infection among HIV-1-infected patients with tuberculosis in Africa and, consequently, high mortality. We assessed the safety and efficacy of trimethoprim-sulphamethoxazole 800 mg/160 mg (co-trimoxazole) prophylaxis in prevention of such infections and in decrease of morbidity and mortality.

METHODS

Between October, 1995, and April, 1998, we enrolled 771 HIV-1 seropositive and HIV-1 and HIV-2 dually seroreactive patients who had sputum-smear-positive pulmonary tuberculosis (median age 32 years [range 18-64], median CD4-cell count 317 cells/microL) attending Abidjan's four largest outpatient tuberculosis treatment centres. Patients were randomly assigned one daily tablet of co-trimoxazole (n=386) or placebo (n=385) 1 month after the start of a standard 6-month tuberculosis regimen. We assessed adherence to study drug and tolerance monthly for 5 months and every 3 months thereafter, as well as rates of admission to hospital.

FINDINGS

Rates of laboratory and clinical adverse events were similar in the two groups. 51 patients in the co-trimoxazole group (13.8/100 person-years) and 86 in the placebo group (25.4/100 person-years) died (decrease In risk 46% [95% CI 23-62], p<0.001). 29 patients on co-trimoxazole (8.2/100 person-years) and 47 on placebo (15.0/100 person-years) were admitted to hospital at least once after randomisation (decrease 43% [10-64]), p=0.02). There were significantly fewer admissions for septicaemia and enteritis in the co-trimoxazole group than in the placebo group.

INTERPRETATION

In HIV-1-infected patients with tuberculosis, daily co-trimoxazole prophylaxis was well tolerated and significantly decreased mortality and hospital admission rates. Our findings may have important implications for improvement of clinical care for such patients in Africa.

Short-course oral zidovudine for prevention of mother-to-child transmission of HIV-1 in Abidjan, Côte d'Ivoire: a randomised trial

BACKGROUND

In Africa, the risk of mother-to-child transmission of HIV-1 infection is high. Short-course perinatal oral zidovudine might decrease the rate of transmission. We assessed the safety and efficacy of such a regimen among HIV-1-seropositive breastfeeding women in Abidjan, Côte d'Ivoire.

METHODS

From April, 1996, to February, 1998, all consenting, eligible HIV-1-seropositive pregnant women attending a public antenatal clinic in Abidjan were enrolled at 36 weeks' gestation and randomly assigned placebo or zidovudine (300 mg tablets), one tablet twice daily until the onset of labour, one tablet at onset of labour, and one tablet every 3 h until delivery. We used HIV-1-DNA PCR to test the infection status of babies at birth, 4 weeks, and 3 months. We stopped the study on Feb 18, 1998, when efficacy results were available from a study in Bangkok, Thailand, in which the same regimen was used in a non-breastfeeding population.

FINDINGS

280 women were enrolled (140 in each group). The median duration of the prenatal drug regimen was 27 days (range 1-80) and the median duration of labour was 7.5 h. Treatment was well tolerated with no withdrawals because of adverse events. All babies were breastfed. Among babies with known infection status at age 3 months, 30 (26.1%) of 115 babies in the placebo group and 19 (16.5%) of 115 in the zidovudine group were identified as HIV-1 infected. The estimated risk of HIV-1 transmission in the placebo and zidovudine groups were 21.7% and 12.2% (p=0.05) at 4 weeks, and 24.9% and 15.7% (p=0.07) at 3 months. Efficacy was 44% (95% CI -1 to 69) at age 4 weeks and 37% (-5 to 63) at 3 months.

INTERPRETATION

Short-course oral zidovudine was safe, well tolerated, and decreased mother-to-child transmission of HIV-1 at age 3 months. Substantial efforts will be needed to ensure successful widespread implementation of such a regimen.

Prevalence of IgG antibodies to Ebola virus in individuals during an Ebola outbreak, Democratic Republic of the Congo, 1995

During the 1995 outbreak of Ebola (EBO) hemorrhagic fever in Kikwit, Democratic Republic of Congo, two surveys using a new ELISA for EBO (subtype Zaire) virus antigen were conducted to assess the prevalence of EBO IgG antibodies among residents of Kikwit and the surrounding area. The first study determined the proportion of antibody-positive individuals who were self-identified forest and city workers from the Kikwit area. Serum samples from 9 (2.2%) of 414 workers had IgG EBO antibodies. The second study determined the proportion of EBO antibody-positive individuals who lived in villages surrounding Kikwit. The prevalence of IgG EBO antibodies in this population was 9.3% (151161). The difference in the overall prevalence of EBO antibodies may indicate that villagers have a greater chance of exposure to EBO virus compared with those living in and in close proximity to cities.

Ebola hemorrhagic fever, Kikwit, Democratic Republic of the Congo, 1995: risk factors for patients without a reported exposure

In 1995, 316 people became ill with Ebola hemorrhagic fever (EHF) in Kikwit, Democratic Republic of the Congo. The exposure source was not reported for 55 patients (17%) at the start of this investigation, and it remained unknown for 12 patients after extensive epidemiologic evaluation. Both admission to a hospital and visiting a person with fever and bleeding were risk factors associated with infection. Nineteen patients appeared to have been exposed while visiting someone with suspected EHF, although they did not provide care. Fourteen of the 19 reported touching the patient with suspected EHF; 5 reported that they had no physical contact. Although close contact while caring for an infected person was probably the major route of transmission in this and previous EHF outbreaks, the virus may have been transmitted by touch, droplet, airborne particle, or fomite; thus, expansion of the use of barrier techniques to include casual contacts might prevent or mitigate future epidemics.

A foodborne outbreak of Campylobacter jejuni (O:33) infection associated with tuna salad: a rare strain in an unusual vehicle

We report a foodborne outbreak of Campylobacter jejuni infection in a summer camp. Outbreak-related cases occurred in 79 persons including 3 secondary cases in campers. Campylobacter jejuni was isolated from stool specimens from 16 of 21 patients who submitted a sample; 13 viable isolates were serotyped and all were serotype O:33 (somatic O scheme) or HL:18 (heat-labile scheme), and biotype III (Lior scheme). This serotype is widely distributed geographically but rarely isolated from humans. Samples of water from the wells supplying the camp were negative for faecal coliforms, and raw milk had not been served in the camp. A matched (1:1) case-control study identified tuna salad served for lunch on 19 July as the likely food item associated with illness (matched odds ratio=22; 95% confidence intervals (CI)=3.6-908). Swimming in the camp pool and other recreational water use in area lakes by the campers were not statistically associated with illness. The precise mechanism of introduction of the organism into the tuna salad remains unknown; contamination most likely occurred through cross-contamination with another food product, the hands of a food handler, or a work surface. Several deficiencies in the operation of the camp kitchen were identified. In Wisconsin, kitchens of such camps are subject to different inspection rules than restaurants. Camp staff, administrators, counselors, food managers, and infirmary staff, should fulfil important roles in their respective areas to prevent future outbreaks.

Hepatitis A infections in Wisconsin: trends in incidence and factors affecting surveillance, 1986-1995

From January 1986 through December 1995, 4,143 cases of hepatitis A virus (HAV) infection were reported in Wisconsin. The annual hepatitis A incidence remained stable from 1986 through 1988, with a mean annual rate of 4.7 cases per 100,000 (endemic HAV incidence rate). During 1989-1993, the incidence of HAV infection increased with a peak in 1992 of 19 cases per 100,000 population. A large foodborne outbreak (1992) and community wide outbreaks among African American residents (1989-1993) and Native Americans residents (1991) were associated with these high rates of HAV infection. The community wide outbreaks affected different groups: among African Americans, incidence rates were highest in young adults 15-34 years old; among Native Americans rates were highest in children 5-14 years old. Approximately 2,343 (57%) patients had no apparent risk factor (e.g., international travel, contact with person with HAV infection) for acquiring HAV infection. Factors limiting control of HAV infection in Wisconsin included poor reporting by laboratories (only 19% of all reported cases were independently reported to the Wisconsin Division of Health by a laboratory and fewer than 50% of these reports were from private laboratories), incomplete reporting by Wisconsin physicians or designees (74% of cases confirmed in Wisconsin laboratories were reported in 1995), failure to submit follow-up case report forms (14% of cases), and a prolonged interval between diagnosis and follow-up (> or = 15 days for 610 cases). Efforts should be enhanced to improve the reporting of cases of HAV infection by private laboratories, particularly through the use of automated electronic reporting.

Clinical features of infections due to Escherichia coli producing heat-stable toxin during an outbreak in Wisconsin: a rarely suspected cause of diarrhea in the United States

In September 1994, a foodborne outbreak of enterotoxigenic Escherichia coli (ETEC) infection occurred in attendees of a banquet in Milwaukee. E. coli was isolated from stool specimens from 13 patients that were comprehensively tested; isolates from five patients were positive for E. coli producing heat-stable toxin, were biochemically identified and serotyped as E. coli O153:H45, and were all resistant to tetracycline, ampicillin, sulfisoxazole, and streptomycin. Diarrhea (100%) and abdominal cramps (83%) were the most prevalent symptoms in 205 cases; vomiting (13%) and fever (19%) were less common. The median duration of diarrhea and abdominal cramps was 6 days and 5 days, respectively. In the United States, health care providers rarely consider ETEC as a possible cause of diarrhea in their patients, and few laboratories offer testing to identify ETEC. Hence, outbreaks of ETEC infection may be underdiagnosed and underreported. As in this outbreak, the relatively high prevalence of diarrhea and cramps lasting > or = 4 days and the low prevalence of vomiting and fever can help distinguish ETEC infection from Norwalk-like virus infection and gastroenteritis due to other causes with incubation times of > or = 15 hours and can provide direction for confirmatory laboratory testing.

Incomplete sanitation of a meat grinder and ingestion of raw ground beef: contributing factors to a large outbreak of Salmonella typhimurium infection

Consumers in the United States continue to eat raw or undercooked foods of animal origin despite public health warnings following several well-publicized outbreaks. We investigated an outbreak of Salmonella serotype Typhimurium infection in 158 patients in Wisconsin during the 1994 Christmas holiday period. To determine the vehicle and source of the outbreak, we conducted cohort and case-control studies, and environmental investigations in butcher shop A. Eating raw ground beef purchased from butcher shop A was the only item significantly associated with illness [cohort study: relative risk = 5.8, 95% confidence interval (CI) = 1.5-21.8; case control study: odds ratio = 46.2, 95% CI = 3.8-2751]. Inadequate cleaning and sanitization of the meat grinder in butcher shop A likely resulted in sustained contamination of ground beef during an 8-day interval. Consumer education, coupled with hazard reduction efforts at multiple stages in the food processing chain, will continue to play an important role in the control of foodborne illness.