Female sex workers population size estimation in Rwanda using a three-source capture-recapture method.

Establishing accurate population size estimates (PSE) is important for prioritising and planning provision of services. Multiple source capture-recapture sampling method increases PSE accuracy and reliability. In August 2018, the three-source capture-recapture (3S-CRC) method was employed with a stringent assumption of sample independence to estimate the number of female sex workers (FSW) in Rwanda. Using Rwanda 2017 FSW hotspots mapping data, street and venue-based FSW were sampled at the sector level of each province and tagged with two unique gifts. Each capture was completed within one week to minimise FSW migration between provinces and recall bias. The three captures had 1042, 1204 and 1488 FSW. There were 111 FSW recaptured between captures 1 and 2; 237 between captures 2 and 3; 203 between captures 1 and 3 and 46 captured in all three. The PSE for street and venue-based FSW in Rwanda lies within 95% credible set: 8328-22 806 with corresponding median of 13 716 FSW. The 3S-CRC technique was low-cost and relatively easy to use for PSE in hard-to-reach populations. This estimate provides the basis for determining the denominators to assess HIV programme performance towards FSW and epidemic control and warrants further PSE for home- and cyber-based FSW in Rwanda.

Introduction of an Alcohol-Related Electronic Screening and Brief Intervention (eSBI) Program to Reduce Hazardous Alcohol Consumption in Namibia's Antiretroviral Treatment (ART) Program.

Alcohol is the most widely abused substance in Namibia and is associated with poor adherence and retention in care among people on antiretroviral therapy (ART). Electronic screening and brief interventions (eSBI) are effective in reducing alcohol consumption in various contexts. We used a mixed methods approach to develop, implement, and evaluate the introduction of an eSBI in two ART clinics in Namibia. Of the 787 participants, 45% reported some alcohol use in the past 12 months and 25% reported hazardous drinking levels. Hazardous drinkers were more likely to be male, separated/widowed/divorced, have a monthly household income > $1000 NAD, and report less than excellent ART adherence. Based on qualitative feedback from participants and providers, ART patients using the eSBI for the first time found it to be a positive and beneficial experience. However, we identified several programmatic considerations that could improve the experience and yield in future implementation studies.

The utility of voluntary counselling and testing data as a source of information on HIV prevalence: a systematic review.

We explored the utility of routine HIV testing data from clinical services for estimating HIV prevalence. A systematic review identified 28 eligible publications, covering concentrated epidemics (16 of 28) and generalized epidemics (12). Of the 16 papers from concentrated epidemics, five presented estimates by risk group and four by testing history with a median HIV prevalence of 1.8% in first-time testers compared with 3% in repeat testers. Two reports from generalized epidemics restricted estimates to asymptomatic clients and three included breakdowns by reason-for-test, with the median HIV prevalence higher in symptomatic clients (62%) than others (24%). Two papers from generalized epidemics showed prevalence estimates based on routine HIV testing data were slightly higher than estimates derived from other surveillance methods, but did not restrict estimates to asymptomatic patients. We conclude that routine HIV testing data may be a supplementary data source for HIV surveillance provided careful analyses are conducted.

Can data from HIV voluntary counselling and testing be used to assess the impact of public health interventions? A literature review.

Routinely collected data from clinical sites offering voluntary counselling and testing (VCT) for HIV diagnosis have been used to evaluate the impact of public health interventions; however, there has been considerable diversity in strategies. To gain an understanding of the outcome of these evaluations and provide the basis for considering methodological issues, we reviewed published studies. Search criteria were met by 20 papers that described 38 interventions, of which 29 were media-related and nine were policy changes. Most (25 of 38) were based on comparisons between two time periods, before and during the intervention, while 13 used multiple time points, including nine that adopted regression methods. About a third (13 out of 38) of the evaluations monitored HIV positivity rates and a small number investigated impact according to sex (six), age (five) and whether clients were new or repeat (three). For the 29 media-related interventions, there was an average 53% increase in the number of HIV tests performed during the intervention compared with beforehand. For policy change interventions, a 35% increase was found. Routinely collected data from VCT sites can be used to evaluate the impact of public health interventions, but attention to methodological issues will maximize their value for evaluation purposes.

Parasite density and malaria morbidity in the Pakistani Punjab.

The relationship between quantitative Plasmodiumfalciparum or P. vivax parasitemia and clinical illness has not been defined in Pakistan or in other areas where malaria transmission is not highly endemic. Standardized questionnaires were given to and physical examinations and parasitologic tests were performed in 8,941 subjects seen in outpatient clinics in 4 villages for 13 consecutive months in the Punjab region of Pakistan. The results, based on multivariable analysis, showed that a clinical diagnosis of malaria, a history of fever, rigors, headache, myalgia, elevated temperature, and a palpable spleen among children were all strongly associated with the presence and density of P. falciparum or P. vivax malaria in a monotonic dose-response fashion. The malaria attributable fraction of a clinical diagnosis of malaria, and the same symptoms and signs also increased with increasing P. falciparum and, to a lesser extent, P. vivax, parasitemia. Unlike in sub-Saharan Africa, clinical illness due to malaria often occurs in the Punjab among adolescents and adults and in patients with parasite densities less than 1,000/microl. Clinical guidelines based upon parasitemia and symptomatology must be adjusted according to the intensity of transmission and be specific for each geographic area.

A case-control study of lung cancer mortality in four rural Arizona smelter towns.

To investigate factors related to lung cancer mortality in four Arizona copper-smelter towns, the authors identified 142 lung cancer cases and 2 matched controls per case from decedent residents during 1979-1990. The authors obtained detailed information on lifetime residential, occupational, and smoking histories via structured telephone interviews with knowledgeable informants. The authors linked estimated historical environmental exposures to smelter emissions (based on atmospheric diffusion modeling of measured sulfur dioxide concentrations) with residential histories to derive individual profiles of residential exposure. The results of this study provided little evidence of a positive association between lung cancer and residential exposure to smelter emissions. Conditional logistic regression analysis revealed a statistically significant positive association between lung cancer and reported employment in copper mines and/or smelters, although specific factors associated with the apparently increased risk among these workers could not be identified in this community-based study.

Introduction of an integrated community-based bancroftian filariasis control program into the Mt Bosavi region of the Southern Highlands of Papua New Guinea.

In mid-1987 a baseline microfilarial prevalence survey was conducted among five villages in the Mt Bosavi region of the Southern Highlands Province of Papua New Guinea. Through use of the Nucleopore filtration technique, it was determined that 48% of villagers had detectable microfilaraemia. The highest prevalence was documented in Fogomaiyu, where the microfilaraemia rate was 92%. On the basis of this initial survey and the expressed interest of the community, the Division of Health in the Southern Highlands Province undertook an integrated community-based pilot control program. The project used two principal control methods: (a) drug treatment with low-dose diethylcarbamazine citrate (DEC) distributed to the community weekly and (b) vector control with permethrin-impregnated bednets. Results six months after the intervention indicate that the program was successful in reducing microfilaraemia at Fogomaiyu village from 92% to 6%. The reduction is principally related to the effects of DEC, although the bednets, by limiting vector-person contact, are expected to reduce the incidence of both filariasis and malaria.

Unexpectedly high HIV prevalence among female sex workers in Bangkok, Thailand in a respondent-driven sampling survey.

The pattern of sex work in Thailand has shifted substantially over the last two decades from direct commercial establishments to indirect venues and non-venue-based settings. This respondent-driven sampling survey was conducted in Bangkok in 2007 among female sex workers (FSW) in non-venue-based settings to pilot a new approach to surveillance among this hidden population. Fifteen initial participants recruited 707 consenting participants who completed a behavioural questionnaire, and provided oral fluid for HIV testing, and urine for sexually transmitted infection (STI) testing. Overall HIV prevalence was 20.2% (95% confidence interval [CI] 16.3-24.7). Three-quarters of women were street-based (75.8%, 95% CI 69.9-81.1) who had an especially high HIV prevalence (22.7%, 95% CI 18.2-28.4); about 10 times higher than that found in routine sentinel surveillance among venue-based FSW (2.5%). STI prevalence (Chlamydia trachomatis and Neisseria gonorrhoeae) was 8.7% (95% CI 6.4-10.8) and 1.0% (95% CI 0.2-1.9), respectively. Lower price per sex act and a current STI infection were independently associated with HIV infection (P < 0.05). High HIV prevalence found among FSW participating in the survey, particularly non-venue-based FSW, identifies need for further prevention efforts. In addition, it identifies a higher-risk segment of FSW not reached through routine sentinel surveillance but accessible through this survey method.

Knowledge, attitudes and practices concerning HIV/AIDS among sex workers in Phnom Penh, Cambodia.

The human immunodeficiency virus (HIV)/AIDS epidemic is currently spreading faster in Cambodia than anywhere else in Asia. Heterosexual transmission of HIV through prostitution is believed to be catalyzing the epidemic, and sex workers (SWs) are at a very high risk for becoming infected with HIV and subsequently developing AIDS. In order to gain a better understanding of the knowledge, attitudes and practices of this highly vulnerable population, face-to-face interviews were conducted with SWs (N = 502) in the capital city, Phnom Penh. The SWs surveyed were predominantly young, uneducated, poor women from rural areas, many of whom remain isolated in brothels. Brothel-based SWs are probably at greatest risk for acquiring HIV. They reported twice as many sexual contacts per day and used condoms less frequently than community-based SWs. The majority of SWs surveyed knew that condoms offered protection against HIV/AIDS, although one-quarter of SWs did not always use condoms. Despite their high level of baseline HIV/AIDS knowledge, nearly all SWs requested that additional health education materials be made available to them and their customers.

Measurement of child mortality in association with a multipurpose birth certificate programme in the Southern Highlands Province of Papua New Guinea.

A simple and inexpensive method for monitoring child mortality in association with birth registration was introduced into the Southern Highlands of Papua New Guinea. Eight thousand two hundred and one newborn infants were registered in 1988, approximately 77% of all children born in that year. The risk of death by age 2 was determined from reports given by the mother on the present status of a previously born child at the time of a recent delivery or during clinic registration of the current birth. This was 91 per 1000 for the province and corresponds to a risk of death by age 1 of 77/1000 by extrapolation using standard lifetables. This method was validated by comparison with a continuing demographic surveillance system covering 30,000 people in the western part of the province. The new birth certificate has been an incentive to increase supervised delivery rates and to generate a register that can be used to increase vaccination coverage.

PIP: The successful experience with the newly established birth registration system in the Southern Highlands Province of Papua New Guinea is presented. The methods of data collection, the practical problems encountered, and the registration, mortality rate, and birth interval results for 1988 are discussed. Problems involved some maternal-child health (MCH) clinic teams being late in giving out birth certificates or not giving certificates at all during 1988. Registration was 77%. Other irregularities included giving certificates before the January 1 start-up or after infants reached their 1st birthday. 98% of registrations were made within the 1st month of birth. Clinic registrations exceeding 100% were due to mothers crossing over district boundaries to use a clinic closer to home, migration, variability of population growth, and underenumeration in the 1980 census. Children born and dying before the 1st clinic visit were not recorded. This province has the highest infant and child mortality rates in all Papua New Guinea. Before 1988, the Tari research unit (TRU) collected demographic data on the Huli language group, which showed that birth data could be collected and child mortality estimated from mother's reports. The certificate was designed to be desirable by mothers. The mortality method of estimating the probability of dying by 2 years involved the tabulation of previous child deaths reported by mothers at the time of birth registration and calculating the ratio of child deaths reported to the number of mothers reporting a previous birth. The retrospective data refer to the period approximately 2/3 of the mean birth interval prior to the date of birth registration collection. Estimates of infant mortality were made using the Coale-Demeny standard life table model. 8201 birth certificates were registered out of the estimated 10,611 births of which 51% were males. 79% (6510) of mothers reported a previous birth of which 592 were dead. The risk of dying by 2 years corresponds to 91/1000 for 1986 with an infant mortality rate of 77/1000. Mothers whose current child was born at a health center had a higher level of mortality (103) for the previous child than mothers whose recent child was born without supervision (81). The mean birth interval was estimated at 40.8 months for Tari district, which is probably overestimated. 62% of 1st time mothers had supervised deliveries. Comparisons are made with TRU data which showed a reversal of results for supervised vs. unsupervised deliveries.

Cigarette smoking and asthma symptom severity among adult asthmatics.

Contrary to what would be expected, smoking habits of asthmatics do not differ from those of the general population: approximately 30% of asthmatic patients smoke cigarettes. Although the relationship between smoking and the incidence of asthma has been well explored, little attention has been paid to documenting the relationship between smoking and asthma symptoms among adults with asthma. The objective of this study was to assess the association of cigarette smoking with asthma symptom severity. The present report is of a cross-sectional study of 225 asthmatics, aged 20-54 years, from six general practice clinics in East Anglia, U.K. The outcome measures are overall asthma symptom score (range 6.3-28) and three asthma symptom domains: respiratory (range 1.3-8), daily activity interference (range 2-8), and physical activity interference (range 3-12), generated from the sum of ordinal responses to questions on asthma symptom severity. Of the sample, 27.0% were current and 22.1% were former smokers. Current smokers more frequently had bothersome asthma symptoms than nonsmokers in both unadjusted analyses and analyses controlling for age, gender, recent visits to the general practitioner for asthma, and asthma medication use (p = 0.06). Respiratory symptoms (p = 0.03) and symptoms that affect daily activities (p = 0.03) were more strongly associated with smoking than symptoms that affect physical activities (p = 0.62). Our data suggest that smoking hastens asthma progression or affects disease control. Increased frequency of symptoms may be an indicator for potential morbidity among asthmatics, especially those who smoke cigarettes. The hazards associated with smoking among asthmatics need to be more clearly emphasized by physicians and public health officials in order to convince people with asthma who smoke to stop.

Motor-vehicle crash fatalities among American Indians and non-Indians in Arizona, 1979 through 1988.

OBJECTIVES: This study evaluated the contributions of rural residence, alcohol use, and pedestrian fatalities to the high American Indian motor-vehicle crash mortality rate in Arizona. METHODS: Records from the Fatal Accident Reporting System were used to examine mortality rates between 1979 and 1988. RESULTS: American Indians had increased relative risks in all motor-vehicle crash categories in all residence-gender groups. The percentage of excess mortality associated with alcohol varied from 36.8% to 66.7%, and the percentage associated with pedestrian deaths ranged from 27.2% to 55.4%. CONCLUSIONS: Efforts to reduce excess motor-vehicle crash mortality among American Indians should concentrate on preventing pedestrian and alcohol-related fatalities.

A case-control study of lung cancer mortality in six Gila Basin, Arizona smelter towns.

To investigate factors related to lung cancer mortality in six Arizona copper smelter towns, we identified 185 lung cancer cases and two matched controls per case from decedent residents during 1979-1990. Detailed information on lifetime residential, occupational, and smoking history was obtained by structured telephone interviews with knowledgeable informants. Interviews were completed for 82% of 183 eligible cases and 88% of the targeted number (366) of controls. Estimated historical environmental exposures to smelter emissions, based on atmospheric diffusion modeling of measured SO2 concentrations, were linked with residential histories to derive individual profiles of residential exposure. Occupational histories were characterized by potential exposure to smelter emissions, asbestos, and ionizing radiation. Conditional logistic regression was used to compare study factors in cases and controls with adjustment for potential confounding factors: gender, Hispanic ethnicity, and smoking. In overall and gender-specific analyses, no statistically significant associations were observed between lung cancer risk and any of the measures of residential exposure to smelter emissions considered (town of residence at time of death, highest level of exposure, and duration or cumulative exposure above background levels), or any of the estimated occupational exposures (definite or potential asbestos, potential ionizing radiation, definite or potential smelter). Among male residents of some, but not all, towns, there was some evidence of a positive association between lung cancer risk and reported copper smelter-related employment (reported as definite), with the highest risk observed for Miami, Arizona. This study provided little evidence of a positive association between lung cancer mortality and residential exposure to smelter emissions. Specific factors associated with the apparent heterogeneity in lung cancer risk across study towns cannot be identified in this community-based study.