Governance, organization, accountability and sustainability of a region-wide school-based deworming program in Loreto, Peru.

Chau Cuica was the name given by the regional government of Loreto in Peru for its school-based deworming program which was initiated in 2012 with a donation of mebendazole from an international non-governmental organization. Embedded in the program from the start was a sentinel surveillance component which consisted of 16 sentinel schools representing Loreto's seven provinces. Coverage rates varied between 35% and 61% over the first two years of the program (and seven deworming cycles). Initial prevalences of soil-transmitted helminth infections were high, with 82.4% of schoolchildren having at least one infection and prevalences of both Ascaris lumbricoides and Trichuris trichiura infections both exceeding 60%. After two years, these prevalences had dropped to 56% for any STH infection, 38% for A. lumbricoides and 34% for T. trichiura. Importantly, the proportions of children with moderate and heavy infections also dropped. Both the regional Ministry of Health and the Ministry of Education were jointly charged to implement this deworming program. The program's costs were estimated to be approximately 22 cents (USD) per child per deworming cycle. The responsibility for the surveillance component was initially undertaken by research partners from a local NGO and a Canadian university, which transferred gradually over the course of the deworming program to being entirely the responsibility of the Ministry of Health. This regional deworming program may serve as a model for other jurisdictions that are planning a school-based deworming program with an integrated surveillance component to monitor impact.

Seroconversion for cytomegalovirus infection in a cohort of pregnant women in Québec, 2010-2013.

Cytomegalovirus (CMV) is the leading cause of congenital infection and non-genetic sensorineural hearing loss in children. There are no recent data on the incidence of CMV infection during pregnancy in Canada. This present study was undertaken to determine the seroprevalence of CMV IgG antibodies and the rate of seroconversion in a cohort of pregnant women in the province of Québec, Canada. We used serum samples and questionnaire data collected as part of the 3D Pregnancy and Birth Cohort Study (2010-2013) conducted in Québec, Canada. CMV IgG antibodies were determined in serum samples collected at the first and third trimesters. Associations between independent variables and seroprevalence were assessed using logistic regression, and associations with seroconversions, by Poisson regression. Of 1938 pregnant women tested, 40·4% were seropositive for CMV at baseline. Previous CMV infection was associated with: working as a daycare educator, lower education, lower income, having had children, first language other than French or English, and being born outside Canada or the United States. Of the 1122 initially seronegative women, 24 (2·1%) seroconverted between their first and third trimesters. The seroconversion rate was 1·4 [95% confidence interval (CI) 0·9-2·1]/10 000 person-days at risk or 3·9 (95% CI 2·5-5·9)/100 pregnancies (assuming a 280-day gestation). The high proportion of pregnant women susceptible to CMV infection (nearly 60%) and the subsequent rate of seroconversion are of concern.

Detection of pathogenic protozoa in the diagnostic laboratory: result reproducibility, specimen pooling, and competency assessment.

Stool microscopy as performed in clinical parasitology laboratories is a complex procedure with subjective interpretation. Quality assurance (QA) programs often emphasize proficiency testing as an assessment tool. We describe a result reproducibility assessment tool, which can form part of a broader QA program, and which is based on the blinded resubmission of selected clinical samples, using concordance between the reports of the initial and resubmitted specimen as an indicator. Specimens preserved in sodium acetate-acetic acid-formalin can be stored for several months for use in such a program. The presence of multiple protozoa in one specimen does not affect concordance. Some dilution of specimens occurs in this process, and this may explain poor concordance when specimens with low protozoal concentrations are resubmitted. Evaluation of this tool in a large parasitology laboratory revealed concordance rates for pathogenic protozoa (Entamoeba histolytica/Entamoeba dispar, Giardia lamblia, and Dientamoeba fragilis) of about 80%, which may be considered for use as a benchmark value. We also used this tool to demonstrate that when pairs of specimens from one patient are pooled to create a single specimen, concordance between the results of the individual and pooled specimens is high.

Using national health weeks to deliver deworming to children: lessons from Mexico.

Mexico established national health weeks (NHWs) in the early 1980s to promote childhood vaccinations. Because of the cumulative worldwide peer-reviewed scientific evidence, the recommendations of the World Health Organization and other international organisations, the political will of the Mexican government and the infrastructure provided by the NHWs, deworming was added to the NHWs in 1993. In addition to the Ministry of Health, several other government organisations participated in administering the deworming component. Tens of millions of school-age and preschool children between the ages of 2 years and 14 years now receive deworming (a single 400 mg dose of albendazole) approximately every 8 months. Between 1993 and 1998 evaluations were carried out in over 90,000 children to determine the effect of NHWs on the prevalence of geohelminth infections. In 1993, the overall prevalence of Ascaris was 20% and that of Trichuris was 15%. Prevalences decreased significantly over time (p <0.001). Treatment efficacy for Ascaris ranged from 91.6% to 85.3%, and for Trichuris, from 97.9% to 42.6%. In 1998, after conducting 12 NHWs with deworming, the respective prevalences were Ascaris 8% and Trichuris 11%. The experience of Mexico in integrating albendazole into its NHWs shows how deworming can be delivered to large numbers of at-risk children using an existing infrastructure. The NHW approach may be generalisable in other countries with successful national vaccination campaigns. The challenge remaining is to sustain the deworming programme until other longer-term behavioural, environmental and socioeconomic changes can be implemented.

Contribution of immunodiagnostic tests to epidemiological/intervention studies of cysticercosis/taeniosis in Mexico.

Cysticercosis is acquired when swine ingest human faeces contaminated with Taenia solium eggs. Humans become tapeworm carriers when they ingest infected pork meat. They can also develop cysticercosis after inadvertently swallowing T. solium eggs. Human neurocysticercosis (NCC) is considered as a public health problem in Mexico and in several countries around the world, mainly developing ones. The development of immunodiagnostic techniques has promoted the conduct of seroepidemiological studies. This review provides insight into the evolution of these techniques, their predictive values and their use in field studies, and summarizes evidence supporting health care practice and policy related to cysticercosis/taeniosis in Mexico. Serological studies in rural and urban settings have demonstrated that close proximity with a tapeworm carrier is the main risk factor for acquiring cysticercosis. Research focusing on the tapeworm carrier generated an ELISA for the detection of Taenia coproantigens and facilitated the evaluation of intervention measures. Health education and self-identification of tapeworm carriers were shown to be successful. However, cestodial treatment as a community-based intervention was not as successful. Current immunodiagnostic techniques can be used to pinpoint transmission foci so that appropriate and effective interventions can be applied. In this way, sustainable control, and even eradication of T. solium may be envisioned.

Seroprevalence of parvovirus B19 infection in daycare educators.

This study was undertaken to provide first-time estimates for the seroprevalence of parvovirus B19 infection among daycare educators in Montréal, Canada, and to identify factors associated with seropositivity. A cross-sectional design was used. Directors and educators from 81 daycare centres (DCCs) were surveyed about DCC and personal characteristics respectively, and serum samples from 477 female educators were tested for parvovirus B19 IgG antibodies. The seroprevalence of parvovirus B19 was 70%. Parvovirus B19 seropositivity was significantly associated with age and with working experience in DCCs, but the latter association was restricted to educators aged less than 40 years. In conclusion, working as a daycare educator appears to be associated with increased risk of acquiring parvovirus B19 infection, but this finding will require further investigation. Because of the large proportion of educators susceptible to acquiring parvovirus B19 infection, our findings also highlight the need for preventive measures.

Tattooing and transfusion-transmitted diseases in Brazil: a hospital-based cross-sectional matched study.

BACKGROUND: Presence of tattoos has been a criterion for temporary deferral of blood donors. Scientific evidence remains equivocal regarding the association between tattooing and transfusion-transmitted diseases (TTDs). METHODS: A cross-sectional matched study was undertaken among adults attending a Brazilian hospital and blood bank. The exposure of interest was having at least one permanent tattoo, and the outcomes were the presence of serological markers for the following TTDs: hepatitis B virus (HBV), hepatitis C virus (HCV) and human immunodeficiency virus (HIV) infections, syphilis, and Chagas' disease. Exposed and unexposed subjects were matched on age, sex, and main clinical complaint. Associations were assessed by odds ratios (ORs), adjusted for confounders by unconditional logistic regression. FINDINGS: The study recruited 345 subjects, 182 with tattoos. Having a tattoo was associated with HCV (OR: 6.41; 95% confidence interval (CI) 1.29, 31.84), and with having at least one positive test for any TTD (OR: 2.05, 95% CI: 1.11, 3.81). No statistically significant associations were found between tattooing and HBV or HIV infection, syphilis or Chagas' disease, but these results are inconclusive given the large CI obtained. INTERPRETATION: Having a tattoo is not an important indicator for testing positive for a TTD, except for HCV infection. Taking into consideration the increasing prevalence of tattooing in the general population, the absolute need of a safe and sustainable blood supply and optimization of the cost-effectiveness of screening blood donors, further research on tattoos is urgently required.

Monitoring and evaluation of large scale helminth control programmes.

An essential component of any helminth control programme is its monitoring and evaluation. These activities provide opportunities to adjust programme implementation, to resolve issues that are problematic, to reinforce personnel satisfaction, to ensure programme quality, and to document the impact of the programme on health and other outcomes. A set of core indicators is proposed to be able to compare the impact of control programmes in different jurisdictions or countries. By ensuring regular programme performance appraisal through monitoring and evaluation activities, future programme implementation can be sustained and cost-effectiveness can be optimized.

Inter-test reliability of the anti-RESA indices based on ELISA tests using eluates from whole blood spots dried on filter paper.

The ring-infected erythrocyte surface antigen (RESA), is one of the falciparum malaria vaccine candidates rarely studied in Brazil. Fieldwork logistics to conduct serology studies is simplified when eluates from whole blood dried on filter paper can be used. Therefore, this study aimed to assess the inter-test reliability for the anti-RESA ELISA-based indices using eluates from filter paper and from serum samples. The study population consisted of 210 individuals (Brazil) from whom matched samples were collected. Anti-RESA ELISA-based index means (+/- S.D.) were 15.29% (+/-28.13%) for filter paper and 11.79% (+/-23.67%) for serum samples. The intra-class correlation coefficient was estimated to be 82.38%, indicating high test reliability. However, there was a significant tendency for filter paper test results to have higher values than serum sample test results (P < 0.001). Explanations for this finding may be the presence of haemoglobin in the eluates from filter paper, which may interfere with ELISA testing.

Tattooing and risk for transfusion-transmitted diseases: the role of the type, number and design of the tattoos, and the conditions in which they were performed.

Tattoos have been shown to be associated with transfusion-transmitted diseases (TTDs), particularly hepatitis B virus (HBV) and hepatitis C virus (HCV) infections. Very little is known about the association between different categories of tattoos and TTDs. In a cross-sectional study in Brazil, we studied 182 individuals with tattoos and assessed the odds of testing positive for a TTD according to tattoo type, number, design and performance conditions. Major findings were significant associations between an increasing number of tattoos and HBV infection (odds ratio (OR) of 2.04 for two tattoos and 3.48 for > or = 3 tattoos), having a non-professional tattoo and testing positive for at least one TTD (OR = 3.25), and having > or = 3 tattoos and testing positive for at least one TTD (OR = 2.98). We suggest that non-professional tattoos and number of tattoos should be assessed as potential deferral criteria in screening blood donors.

Increasing referral of at-risk travelers to travel health clinics: evaluation of a health promotion intervention targeted to travel agents.

BACKGROUND: Increases in travel-related illness require new partnerships to ensure travelers are prepared for health risks abroad. The travel agent is one such partner and efforts to encourage travel agents to refer at-risk travelers to travel health clinics may help in reducing travel-attributable morbidity. METHODS: A health promotion intervention encouraging travel agents to refer at-risk travelers to travel health clinics was evaluated. Information on the knowledge, attitudes, and behaviors of travel agents before and after the intervention was compared using two self-administered questionnaires. The Wilcoxon signed rank test was used to compare the mean difference in overall scores to evaluate the overall impact of the intervention and also subscores for each of the behavioral construct groupings (attitudes, barriers, intent, and subjective norms). Multiple regression techniques were used to evaluate which travel agent characteristics were independently associated with a stronger effect of the intervention. RESULTS: A small improvement in travel agents overall attitudes and beliefs (p =.03) was found, in particular their intention to refer (p =.01). Sixty-five percent of travel agents self-reported an increase in referral behavior; owners or managers of the agency were significantly more likely to do so than other travel agents (OR = 7.25; 95% CI: 1.64 32.06). Older travel agents, those that worked longer hours and those with some past referral experience, had significantly higher post-intervention scores. CONCLUSIONS: Travel agents can be willing partners in referral, and agencies should be encouraged to develop specific referral policies. Future research may be directed toward investigating the role of health education in certification curricula, the effectiveness of different types of health promotion interventions, including Internet-facilitated interventions, and the direct impact that such interventions would have on travelers attending travel health clinics.

Extending anthelminthic coverage to non-enrolled school-age children using a simple and low-cost method.

School health programmes are the basis of the strategy defined by WHO to reduce morbidity due to soil-transmitted nematodes and schistosomes in school age populations in developing countries. However, low rates of school enrollment can be a major factor limiting their success. In the present study enrolled children were informed by teachers on the date of the next deworming campaign and were invited to pass along this information to parents, siblings and friends of school-age. On the day of the deworming campaign, teachers were instructed to administer anthelminthics to enrolled and not enrolled school-age children present at school. In the month following the treatment day, information about coverage was collected by questionnaire in 257 households in two regions of Unguja Island, Zanzibar. Over 89% of school age children resulted treated (98.9% of those enrolled plus 60% of those not enrolled). The additional cost of treating non-enrolled is limited to the cost of providing additional doses of anthelminthic drug in each school. Non-enrolled school age children can easily, successfully and inexpensively included in school based deworming campaign. Managers of control programmes are invited to test this method adapting it in their particular and cultural environment.

Efficacy of new low-cost filtration device for recovering Schistosoma haematobium eggs from urine.

A new, inexpensive filtration device for the diagnosis of urinary schistosomiasis was tested against the commonly used Millipore device. The experimental protocol was performed with 25 urine samples known to be positive for Schistosoma haematobium. The results suggest that the new device is as effective as the Millipore device for the diagnosis of urinary schistosomiasis. Its low cost will be attractive to schistosomiasis control programs.

Comparison of methods to analyse imprecise faecal coliform count data from environmental samples.

Imprecise values arise when bacterial colonies are too numerous to be counted or when no colonies grow at a specific dilution. Our objective was to show the usefulness of multiple imputation in analysing data containing imprecise values. We also indicate that interval censored regression, which is faster computationally in situations where it applies, can be used, providing similar estimates to imputation. We used bacteriological data from a large epidemiological study in daycare centres to illustrate this method and compared it to a standard method which uses single exact values for the imprecise data. The data consisted of numbers of FC on children's and educators' hands, from sandboxes and from playareas. In general, we found that multiple imputation and interval censored regression provided more conservative intervals than the standard method. The discrepancy in the results highlights both the importance of using a method that best captures the uncertainty in the data and how different conclusions might be drawn. This can be crucial for both researchers and those who are involved in formulating and regulating standards for bacteriological contamination.

Tattoos as risk factors for transfusion-transmitted diseases.

BACKGROUND: Several infectious diseases have been found to be associated with tattooing, including some transfusion-transmitted diseases (TTDs). Information on tattooing has been included in screening interviews of prospective blood donors and may be a reason for deferral. METHODS: Review of articles identified through Medline (and other computerized data bases) using medical subject heading (MeSH) terms and textwords for "tattooing," "transfusion", "hepatitis", "human immunodeficiency virus", "acquired immunodeficiency syndrome", "syphilis", "Chagas disease", "infection", "risk factors", and their combinations. RESULTS: There is strong evidence for the transmission of hepatitis B virus (HBV) infection, hepatitis C virus (HCV) infection, and syphilis by tattooing. Tattooing may also transmit the human immunodeficiency virus (HIV), although convincing evidence is still lacking. There is little or no evidence that other TTDs can be transmitted by tattooing. Epidemiologic studies to date have shown a large variation in odds ratio estimates of the association between tattooing and HBV, HCV, and HIV infections. CONCLUSION: Further studies are required to clarify the risk of tattoos in transmitting infectious diseases through blood transfusions. A reassessment of tattoos as a screening criterion among blood donors is justified.

School enrollment in Zanzibar linked to children's age and helminth infections.

UNLABELLED: School health programmes have been identified as a cost-effective strategy to reduce morbidity due to soil-transmitted helminths in the school-age population, but the low rate of school enrollment in developing countries is a major factor limiting their success. OBJECTIVE: The present study was conducted to identify reasons for non-enrollment and to evaluate differences in the occurrence of helminth infection between enrolled and non-enrolled children in Zanzibar, United Republic of Tanzania. METHOD: A questionnaire was submitted to 520 households to obtain information about enrollment and other socio-economic indicators. In addition, one school-age child was randomly selected in each household and investigated for soil-transmitted helminth infection. RESULTS: Overall, 71% of school-age children were enrolled. Enrollment increased with age. Only 41% of children under 9 years of age were enrolled compared to 91% in children older than 12 years. Enrollment is delayed because of an insufficient number of schools. Among non-enrolled school-age children, the proportion of heavy intensity infections was twice that of enrolled school-age children. CONCLUSIONS: Most of the non-enrolled school-age children live together with enrolled siblings in the same household, thereby representing an important opportunity for effective outreach activities. The effectiveness of the school-based helminth control programme in reducing the intensity of infection was confirmed. The significant gains achieved by enrolled school-age children in this study must be viewed as an attainable goal for the important numbers of non-enrolled school-age children in endemic areas. Decision-makers must ensure that outreach activities are included in helminth control programmes targeted to school-age children.

Selection of subjects for hospital-based epidemiologic studies based on outward manifestations of disease.

Selection of controls with the same outward manifestations of disease as the case group has been proposed as a means of avoiding selection bias in hospital-based case-control studies. The same strategy, however, can lead to selection bias in registry-based case-control studies that use control diseases with similar manifestations whose diagnoses might have been associated with the exposure. Matching exposed and unexposed subjects by outward manifestation of disease can be used in cohort and cross-sectional studies aiming at decreasing selection bias. This strategy in these study designs may lead to overmatching, but this will not bias the relative-risk estimates. Efficiency considerations in applying this strategy require further investigation.

Comparison between two common methods for reporting cold and diarrhoea symptoms of children in daycare centre research.

BACKGROUND: The increasing number of children attending day care centres (DCCs) in industrialized countries has refocused attention on the occurrence of infections and infectious diseases in these settings. OBJECTIVE: To evaluate the agreement between two methods (parent method vs. educator method) for reporting the occurrence of respiratory and diarrhoeal infections. METHODS: Fifty-two DCCs in Quebec, Canada, participated. Both educators and parents were invited to fill in calendars on which they would indicate the occurrence of colds and diarrhoea. For the parents' method, parents were telephoned biweekly to record their calendar information. For the educators' method, educators returned their calendar pages monthly (following prompting by phone, when necessary). RESULTS: Three hundred and thirty-three parents of toddlers participated in the 15-month reporting period between September 1996 and November 1997. The average agreement between the two methods was low (13.5% for colds and 9.8% for diarrhoea). Overall estimates of the incidence rates of respiratory and diarrhoeal infections based on parents' method were higher than those based on educators' method. CONCLUSIONS: Parents' data lead to larger estimations of incidence rates and are probably more valid than educators' data.