Joseph J. Valadez

Preventing HIV infection through peer education and condom promotion among truck drivers and their sexual partners in Tanzania, 1990-1993.

HIV prevention through peer education and condom promotion among truck drivers and their sexual partners is described. Trends during an initial 18-month intensive phase, followed by a 24-month maintenance phase, were monitored with surveys. Trends for self-reported condom use were: increase among men (56 to 74%) during the first phase with a decrease (72%) during the maintenance phase. Respective figures for women were 51%, 91% and 70%. Multivariate analyses revealed that men most likely to report using condoms were unmarried, had children, were more educated, had previously reported a genital ulcer, and perceived themselves at risk for HIV infection (OR = 1.95-3.47). Women tending to use condoms were unmarried, aware of the limitations of condoms, not in denial as to the existence of HIV, harboured inaccurate information about HIV transmission and were afraid (OR = 1.35-2.52). Both sets of results suggest that the most sexually experienced men and women who did not have a permanent stable relationship and who perceived themselves at risk, were most likely to use a condom. Peer education was an effective tool for increasing knowledge and encouraging appropriate behaviour change. It was most effective as an intensive high-input intervention and sustainable with the relatively stable population of truck drivers.

New evidence on the HIV epidemic in Libya: why countries must implement prevention programs among people who inject drugs.

Background:Libya had one of the worlds largest nosocomial HIV outbreaks in the late 1990s leading to the detention of 6 foreign medical workers. They were released in 2007 after the Libyan Government and the European Union agreed to humanitarian cooperation that included the development of Libyas first National HIV Strategy and the research reported in this article. Despite the absence of sound evidence on the status and dynamics of Libyas HIV epidemic, some officials posited that injecting drug use was the main mode of transmission. We therefore sought to assess HIV prevalence and related risk factors among people who inject drugs (PWID) in Tripoli. Methods:We conducted a cross-sectional survey among 328 PWID in Tripoli using respondent-driven sampling. We collected behavioral data and blood samples for HIV, hepatitis C virus, and hepatitis B virus testing. Results:We estimate an HIV prevalence of 87%, hepatitis C virus prevalence of 94%, and hepatitis B virus prevalence of 5%. We detected injecting drug use–related and sexual risk factors in the context of poor access to comprehensive services for HIV prevention and mitigation. For example, most respondents (85%) reported having shared needles. Conclusions:In this first biobehavioral survey among PWID in Libya, we detected one of the highest (or even the highest) levels of HIV infection worldwide in the absence of a comprehensive harm-reduction program. There is an urgent need to implement an effective National HIV Strategy informed by the results of this research, especially because recent military events and related sociopolitical disruption and migration might lead to a further expansion of the epidemic.

Are patent medicine vendors effective agents in malaria control? Using lot quality assurance sampling to assess quality of practice in Jigawa, Nigeria.

Background Patent medicine vendors (PMV) provide antimalarial treatment and care throughout Sub-Saharan Africa, and can play an important role in the fight against malaria. Their close-to-client infrastructure could enable lifesaving artemisinin-based combination therapy (ACT) to reach patients in time. However, systematic assessments of drug sellers’ performance quality are crucial if their role is to be managed within the health system. Lot quality assurance sampling (LQAS) could be an efficient method to monitor and evaluate PMV practice, but has so far never been used for this purpose. Methods In support of the Nigeria Malaria Booster Program we assessed PMV practices in three Senatorial Districts (SDs) of Jigawa, Nigeria. A two-stage LQAS assessed whether at least 80% of PMV stores in SDs used national treatment guidelines. Acceptable sampling errors were set in consultation with government officials (alpha and beta <0.10). The hypergeometric formula determined sample sizes and cut-off values for SDs. A structured assessment tool identified high and low performing SDs for quality of care indicators. Findings Drug vendors performed poorly in all SDs of Jigawa for all indicators. For example, all SDs failed for stocking and selling first-line antimalarials. PMV sold no longer recommended antimalarials, such as Chloroquine, Sulfadoxine-Pyrimethamine and oral Artesunate monotherapy. Most PMV were ignorant of and lacked training about new treatment guidelines that had endorsed ACTs as first-line treatment for uncomplicated malaria. Conclusion There is urgent need to regularly monitor and improve the availability and quality of malaria treatment provided by medicine sellers in Nigeria; the irrational use of antimalarials in the ACT era revealed in this study bears a high risk of economic loss, death and development of drug resistance. LQAS has been shown to be a suitable method for monitoring malaria-related indicators among PMV, and should be applied in Nigeria and elsewhere to improve service delivery.

Multiple Category-Lot Quality Assurance Sampling: A New Classification System with Application to Schistosomiasis Control

Background Originally a binary classifier, Lot Quality Assurance Sampling (LQAS) has proven to be a useful tool for classification of the prevalence of Schistosoma mansoni into multiple categories (≤10%, >10 and <50%, ≥50%), and semi-curtailed sampling has been shown to effectively reduce the number of observations needed to reach a decision. To date the statistical underpinnings for Multiple Category-LQAS (MC-LQAS) have not received full treatment. We explore the analytical properties of MC-LQAS, and validate its use for the classification of S. mansoni prevalence in multiple settings in East Africa. Methodology We outline MC-LQAS design principles and formulae for operating characteristic curves. In addition, we derive the average sample number for MC-LQAS when utilizing semi-curtailed sampling and introduce curtailed sampling in this setting. We also assess the performance of MC-LQAS designs with maximum sample sizes of n = 15 and n = 25 via a weighted kappa-statistic using S. mansoni data collected in 388 schools from four studies in East Africa. Principle Findings Overall performance of MC-LQAS classification was high (kappa-statistic of 0.87). In three of the studies, the kappa-statistic for a design with n = 15 was greater than 0.75. In the fourth study, where these designs performed poorly (kappa-statistic less than 0.50), the majority of observations fell in regions where potential error is known to be high. Employment of semi-curtailed and curtailed sampling further reduced the sample size by as many as 0.5 and 3.5 observations per school, respectively, without increasing classification error. Conclusion/Significance This work provides the needed analytics to understand the properties of MC-LQAS for assessing the prevalance of S. mansoni and shows that in most settings a sample size of 15 children provides a reliable classification of schools.

Putting the C back into the ABCs: a multi-year, multi-region investigation of condom use by Ugandan youths 2003-2010.

A major strategy for preventing transmission of HIV and other STIs is the consistent use of condoms during sexual intercourse. Condom use among youths is particularly important to reduce the number of new cases and the national prevalence. Condom use has been often promoted by the Uganda National AIDS Commission. Although a number of studies have established an association between condom use at one’s sexual debut and future condom use, few studies have explored this association over time, and whether the results are generalizable across multiple locations. This multi time point, multi district study assesses the relationship between sexual debut and condom use and consistent use of condoms thereafter. Uganda has used Lot Quality Assurance Sampling surveys since 2003 to monitor district level HIV programs and improve access to HIV health services. This study includes 4518 sexually active youths interviewed at five time points (2003–2010) in up to 23 districts located across Uganda. Using logistic regression, we measured the association of condom use at first sexual intercourse on recent condom usage, controlling for several factors including: age, sex, education, marital status, age at first intercourse, geographical location, and survey year. The odds of condom use at last intercourse, using a condom at last intercourse with a non-regular partner, and consistently using a condom are, respectively, 9.63 (95%WaldCI = 8.03–11.56), 3.48 (95%WaldCI = 2.27–5.33), and 11.12 (95%WaldCI = 8.95–13.81) times more likely for those individuals using condoms during their sexual debut. These values did not decrease by more than 20% when controlling for potential confounders. The results suggest that HIV prevention programs should encourage condom use among youth during sexual debut. Success with this outcome may have a lasting influence on preventing HIV and other STIs later in life.

Cluster designs to assess the prevalence of acute malnutrition by lot quality assurance sampling: a validation study by computer simulation

Traditional lot quality assurance sampling (LQAS) methods require simple random sampling to guarantee valid results. However, cluster sampling has been proposed to reduce the number of random starting points. This study uses simulations to examine the classification error of two such designs, a 67×3 (67 clusters of three observations) and a 33×6 (33 clusters of six observations) sampling scheme to assess the prevalence of global acute malnutrition (GAM). Further, we explore the use of a 67×3 sequential sampling scheme for LQAS classification of GAM prevalence. Results indicate that, for independent clusters with moderate intracluster correlation for the GAM outcome, the three sampling designs maintain approximate validity for LQAS analysis. Sequential sampling can substantially reduce the average sample size that is required for data collection. The presence of intercluster correlation can impact dramatically the classification error that is associated with LQAS analysis.

A psychological epidemiology of people seeking HIV/AIDS counselling in Kenya: an approach for improving counsellor training.

OBJECTIVE This study develops a typology of psychological problems reported during HIV/AIDS counselling. This typology provides a framework for training paraprofessional counsellors (PPCs) in East Africa. DESIGN Study participants included 307 Kenyans tested for HIV at any of six clinics in Nairobi specialising in STDs, tuberculosis and other infectious diseases. Pre-test, post-test, and follow-up counselling was provided by 16 PPCs who are themselves HIV-positive. Data consisted of demographic, physical and psychological information reported by 168 clients who sought follow-up counselling. METHODS Counselling data were coded using an ipsative method; a unique code was assigned to every distinct topic. Factor analysis with a Varimax rotation reduced the original psychological variables into logical groupings. Multivariate analysis examined the relationship of factors and demographic characteristics. RESULTS Clients reported 1-10 physical and 1-23 psychological complaints in a single session. Sixty-five percent of female clients reported > or = eight psychological problems; 49% of males reported > or = eight psychological problems. Factor analyses allowed the 109 reported psychological events to be assigned to 15 categories of problems. Multivariate analyses explained little of the variance in the relationship between each clients demographic profile and the psychological factors. CONCLUSIONS Training for PPCs should be relevant to problems encountered during counselling. Results indicate that PPCs can expect clients to present one or more of the 15 factors during counselling. Demographic characteristics explained small amounts of variance in the distribution of factor scores. The 15 factors produced in this study, although descriptive and preliminary, could form the basis of a training curriculum for HIV PPCs.

Household Work as an Ordeal: Culture of Standards Versus Standardization of Culture

Some feminist authors assert that household work is inexorably debasing for women. This paper questions that hypothesis on both theoretical and methodological grounds by exploring (a) ambiguities in the links between patriarchy and capitalism and (b) the meanings of housework across cultural and historical settings. A research agenda is proposed in which it is suggested that housework is both an ordeal of civility through which individuals judge their joint membership in the same social milieu and an ordeal of conviviality through which individuals who pass within the same milieu reinforce social bonds. The conclusion elucidates why changes in the division of housework should not be synonymous with the eradication of tasks.

Filling the Knowledge Gap: Measuring HIV Prevalence and Risk Factors among Men Who Have Sex with Men and Female Sex Workers in Tripoli, Libya

Background Publications on Libya’s HIV epidemic mostly examined the victims of the tragic nosocomial HIV outbreak in the 1990s and the related dispute about the detention of foreign medical workers. The dispute resolution in 2003 included an agreement with the European Union on humanitarian cooperation and the development of Libya’s first National HIV Strategy. As part of this we conducted Libya’s first bio-behavioural survey among men having sex with men (MSM) and female sex workers (FSW). Methods Using respondent-driven sampling, we conducted a cross-sectional study to estimate the prevalence of HIV, hepatitis B virus (HBV), hepatitis C virus (HCV), and related risk factors among 227 MSM and 69 FSW in Tripoli (FSW recruitment ended prematurely due to the political events in 2011). Results For MSM we estimated an HIV prevalence of 3.1%, HBV prevalence of 2.9%, and HCV prevalence of 7.3%, and for FSW an HIV prevalence of 15.7%, HBV prevalence of 0%, and HCV prevalence of 5.2%. We detected high levels of risk behaviours, poor HIV-related knowledge, high stigma and lack of prevention programmes. These results must be interpreted in the context of the political situation which prohibited reaching an ideal sample size for FSW. Conclusion There is urgent need to implement an effective National HIV Strategy informed by the results of this research. The risk of transmission within different risk groups and to the general population may be high given the recent military events that led to increased violence, migration, and the disruption of essential HIV-related services.

A Novel Approach to Evaluating the Iron and Folate Status of Women of Reproductive Age in Uzbekistan after 3 Years of Flour Fortification with Micronutrients

Background The Uzbekistan 1996 Demographic Health Survey reported 60.4% of women of reproductive age (WRA) had low hemoglobin concentrations (<120 g/L), and anemia was an important public health problem. Fortification of wheat flour was identified as an appropriate intervention to address anemia due to the ubiquitous consumption of wheat flour. A National Flour Fortification Program (NFFP) was implemented in 2005. Methodology/Principal Findings After 3-years of the NFFP, a national survey using large country-lot quality assurance sampling was carried out to assess iron, folate, hemoglobin and inflammation status of WRA; the coverage and knowledge of the fortified first grade UzDonMakhsulot (UDM) flour/grey loaf program; and consumption habits of women to investigate the dietary factors associated with anemia. Estimated anemia prevalence was 34.4% (95% CI: 32.0, 36.7), iron depletion 47.5% (95% CI: 45.1, 49.9) and folate deficiency 28.8% (95% CI: 26.8, 30.8); the effect of inflammation was minimal (4% with CRP >5 mg/L). Severe anemia was more prevalent among folate deficient than iron depleted WRA. Presence of UDM first grade flour or the grey loaf was reported in 71.3% of households. Among WRA, 32.1% were aware of UDM fortification; only 3.7% mentioned the benefits of fortification and 12.5% understood causes of anemia. Consumption of heme iron-containing food (91%) and iron absorption enhancers (97%) was high, as was the consumption of iron absorption inhibitors (95%). Conclusions/Significance The NFFP coincided with a substantial decline in the prevalence of anemia. Folate deficiency was a stronger predictor of severe anemia than iron depletion. However, the prevalence of iron depletion was high, suggesting that women are not eating enough iron or iron absorption is inhibited. Fortified products were prevalent throughout Uzbekistan, though UDM flour must be adequately fortified and monitored in the future. Knowledge of fortification and anemia was low, suggesting consumer education should be prioritized.