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This study evaluated a school-based and a community-based scheme for diagnosis, treatment and follow-up of schistosomiasis mansoni among school-aged children in views of resolution CD49.R19 of the Pan American Health Organization toward the elimination of schistosomiasis as a public health problem in the Americas and subsequent commitments endorsed by the Brazilian government. The school-aged population from a representative municipality of the endemic area of Northeastern Brazil was randomly allocated to either school-based or community-based scheme. The two schemes were compared with regard to coverage of diagnosis by the Kato-Katz method (KK) at baseline, treatment of the positives for Schistosoma mansoni with praziquantel, treatment of the positives for soil-transmitted helminthes (STH) with mebendazole, as well as follow-up of treatment efficacy and reinfection assessed respectively at four and 12 months after treatment. Nutritional status of the positives for S. mansoni was assessed at baseline and re-assessed at 12 months after treatment. Coverage of diagnosis and treatment was satisfactory (>75%) in both schemes. Diagnosis coverage at baseline and at 12 months was significantly higher in the community scheme, whereas treatment coverage did not differ significantly between the two schemes either at baseline or at 12 months. The number of children covered per day was significantly higher in the schools than in the community at baseline but not at follow-up, when daily coverage was higher in the community. With regard to S. mansoni, overall treatment efficacy rate at four months was 90.8%, and reinfection rate at 12 months was 21.6%. For STH, overall treatment efficacy was 45.4% and reinfection, 32.8%. The nutritional status of the positives for S. mansoni at baseline did not change significantly at 12 months post-treatment. Actions targeted at this particularly vulnerable high-risk group should combine school-based and community-based interventions as well as preventive measures to reduce transmission.

School-aged children (6-15 years) from the endemic area of Pernambuco were evaluated both as a target group for and an indicator of schistosomiasis control in the community. Parasitological data were drawn from baseline stool surveys of whole populations that were obtained to diagnose Schistosoma mansoni infection. Nineteen representative localities were selected for assessing the prevalence of schistosomiasis among individuals in the following age groups: 0-5, 6-15, 16-25, 26-40 and 41-80 years. For each locality, the prevalence in each age group was compared to that of the overall population using contingency table analysis. To select a reference group, the operational difficulties of conducting residential surveys were considered. School-aged children may be considered to be the group of choice as the reference group for the overall population for the following reasons: (i) the prevalence of schistosomiasis in this age group had the highest correlation with the prevalence in the overall population (r = 0.967), (ii) this age group is particularly vulnerable to infection and plays an important role in parasite transmission and (iii) school-aged children are the main target of the World Health Organization in terms of helminth control. The Schistosomiasis Control Program should consider school-aged children both as a reference group for assessing the need for intervention at the community level and as a target group for integrated health care actions of the Unified Health System that are focused on high-risk groups.

The World Health Organization (WHO, 2010) estimates that 7.1 million people are infected with Schistsosoma mansoni in the Americas, 95% of which in Brazil. Resolution CD49.R19 of the Pan American Health Organization (PAHO, 2009) urged Member States to commit themselves to eliminate or reduce neglected diseases and other infections related to poverty for which tools exist, to levels so that these diseases are no longer considered public health problems by year 2015. The resolution considered schistosomiasis as one of the diseases whose prevalence can be drastically reduced in the Americas with available cost-effective interventions, and approved goals and strategies to be adopted by the countries according to their health policies, epidemiological situation and health service structure. The present chapter firstly compares similarities and differences in the main goals and primary strategies between the current recommendations of the Brazilian Schistomiasis Control Programme (PCE), Ministry of Health (MS), and those of CD49.R19, with particular emphasis on improving coverage of diagnosis and treatment. Secondly, it examines data from a representative endemic area to provide evidence that an approach including schoolbased diagnosis and treatment would enable short-term improved access to and coverage of the control actions targeted at the school-aged group. Thirdly, it applies spatial analysis to evaluate baseline and post-treatment prevalence data from an endemic locality to show the feasibility of mapping re-infection risk areas based on the identified “hot spots”, thus contributing to improve preventive measures such as environmental sanitation and snail control. Finally, it will be argued that the current MS strategy can be further improved towards the goal of drastically reducing prevalence in the foreseeable future taking into account the epidemiological situation and health service structure without compromising the country’s health policies.

Background Since its beginning in 1999, the Schistosomiasis Control Program within the Unified Health System (PCE-SUS) has registered a cumulative coverage of just 20% of the population from the Rainforest Zone of Pernambuco (ZMP), northeast Brazil. This jeopardizes the accomplishment of the minimum goal of the Fifty-Fourth World Health Assembly, resolution WHA54.19, of providing treatment for schistosomiasis and soil-transmitted helminthiases (STH) to 75% of school-aged children at risk, which requires attending at least 166,000 residents in the 7–14 age range by year 2010 in that important endemic area. In the present study, secondary demographic and parasitological data from a representative municipality of the ZMP are analyzed to provide evidence that the current, community-based approach to control schistosomiasis and STH is unlikely to attain the WHA-54.19 minimum goal and to suggest that school-based control actions are also needed. Methodology/Principal Findings Data available on the PCE-SUS activities related to diagnosis and treatment of the population from the study municipality were obtained from the State Secretary of Health of Pernambuco (SES/PE) for 2002–2006, complemented by the Municipal Secretary of Health (SMS) for 2003–2004. Data from a school-based stool survey carried out by the Schistosomiasis Reference Service of the Oswaldo Cruz Foundation (SRE/Fiocruz) in 2004 were used to provide information on infection status variation among school-aged children (7–14 years). According to the SES, from 2004 to 2006, only 2,977 (19.5%) of the estimated 15,288 residents of all ages were examined, of which 396 (13.3%) were positive for Schistosoma mansoni. Among these, only 180 (45.5%) were treated. According to the SMS, of the 1,766 examined in the 2003–2004 population stool survey 570 (32.3%) were children aged 7–14 years. One year later, the SRE/Fiocruz school survey revealed that the infection status among those children remained unchanged at 14%–15% prevalence. By 2006, the school-aged population was estimated at 2,981, of which 2,007 (67.3%) were enrolled as pupils. Conclusions It is suggested that in the most troubled municipalities individual diagnosis and treatment should be concentrated in school-aged children rather than the whole population. School-based actions involving teachers and children's families may help the health teams to scale up control actions in order to attain the WHA-54.19 minimum goal. This strategy should involve health and education organs and include both enrolled and non-enrolled children., Author Summary In 2001, a World Health Assembly resolution urged member states to ensure treatment against schistosomiasis and soil-transmitted helminthiasis in endemic areas with the goal of attaining a minimum target of at least 75% of all school-aged children by 2010. In the highly endemic Rainforest Zone of Pernambuco (ZMP), northeast Brazil, the Schistosomiasis Control Program has registered a cumulative coverage of only 20% of the population at risk, which jeopardizes the accomplishment of the minimum target for that area. Demographic and parasitological data from a representative municipality of the ZMP provide evidence that the current, community-based approach to control can be complemented with school-based actions. In the most troubled municipalities, individual diagnosis and treatment could be focused on school-aged children rather than whole populations without compromising the principles of the primary health care system. Local health and education teams should be encouraged to include school-based interventions to scale up coverage and achieve a rapid impact on infection.

Resolution 19 of the 54th World Health Assembly (WHA-54.19) urged member nations to promote preventive measures, ensure treatment and mobilize resources for control of schistosomiasis and soil-transmitted helminthiases (STH). The minimum target is to attend 75% of all school-age children at risk by year 2010. The Brazilian Ministry of Health (MoH) recommends biennial surveys of whole communities and treatment of the positives through the Schistosomiasis Control Program within the Unified Health System (PCE-SUS). However, by 2004 the PCE-SUS had covered only 8.4% of the 1.2 million residents in the Rainforest Zone of Pernambuco (ZMP). Six of the 43 municipalities still remained unattended. Only three of the municipalities already surveyed reached coverage of 25% or more. At least 154 thousand children in the 7-14 years old range have to be examined (and treated if positive) within the next five years to attend the minimum target of the WHA 54.19 for the ZMP. To make this target feasible, it is suggested that from 2006 to 2010 the PCE-SUS actions should be complemented with school-based diagnosis and treatment, involving health and educational organs as well as community associations to include both children in schools and non-enrolled school-age children.

The Program for Schistosomiasis Control within the Unified Health System (PCE-SUS) was implemented by 1999 in the Rainforest Zone or "Zona da Mata" of Pernambuco (ZMP) aiming to carry out biennial stool surveys of whole populations through municipal health organs followed by treatment of the positives through the local units of the Family Health Program (PSF). Yearly reports from the Health Department of Pernambuco State (SES/PE) from 2002 to 2004 on the PCE-SUS surveys were assessed to evaluate whether the current estimates of prevalence in the municipalities of the ZMP are based on reliable samples so as to allow considerations on the real situation of schistosomiasis in that area. The surveys carried out in that period did not follow the major principles underlying sampling design, thus posing problems in both precision and validity of the estimates. Only 12 out of 43 municipalities had minimally reliable estimates: five with moderate prevalence (10-50%) and seven with low prevalence (< 10%). Surveys with appropriate sampling procedures aimed either at representative target groups (school-aged children) or communities are recommended for the ZMP and other endemic areas not only to provide reliable information on the current situation of schistosomiasis but also to plan adequate control strategies.