|dc.description.abstract||Schistosomiasis is a trematode worm infection of the genus Schistosoma with five species known to infect humans. It is endemic in 78 countries, 42 of which are in the Africa, 16 in the Eastern Mediterranean, 10 in the Americas, six in the Western Pacific, three in Southeast Asia and one in Europe. In 2015, the Disability-Adjusted Life Years (DALYs) due to schistosomiasis was estimated at 3.514 million and WHO estimated that 118.5 million school-aged children and 100.2 million adults are in need of preventive chemotherapy for schistosomiasis.
Preventive chemotherapy, through regular mass drug administration (MDA) of praziquantel, was endorsed by World Health Assembly in 2001 as the main strategy for schistosomiasis control through WHA resolution 54.19. Treatment with praziquantel at a dose of 40 mg/kg aims to reduce morbidity and mortality, and prevent new infection by limiting transmission through reduction of the human reservoir host. The WHO target was to regularly treat a minimum of 75% of the high-risk population, and up to 100% of all school-age children at risk of morbidity by 2010. The 2012-2020 Schistosomiasis Strategic Plan has set three objectives, one of which was to control morbidity due to schistosomiasis by 2020 by targeting 100% geographical and 75% national MDA coverage. MDA has been implemented and included in the national schistosomiasis control programs of many countries such as Uganda, Sierra Leone, Burkina Faso, Brazil, Mali, Niger, the People’s Republic of China, and the Philippines.
In the Philippines, zoonotic Schistosoma japonicum infection is endemic in 28 provinces in 12 regions of the country, with an estimated 28 million people at risk of infection. In the national prevalence survey conducted from 2005-2008, the estimated mean human prevalence was 1.30% (range 0.08%-6.30%). For over two decades human MDA has been the cornerstone of schistosomiasis control in the country. In an effort to eliminate schistosomiasis as a public health problem, and to protect the exposed population from developing chronic infection, the Department of Health (DOH) has ordered the conduct of annual MDA in 24 endemic provinces among those aged 5-65 years commencing in 2009. The aim was to attain at least 85% drug coverage for at least three years or until disease elimination (human prevalence <1%) was achieved. However, prevalence rates in 2012-2013 reported that 10 out of 13 provinces remained above 1%. The national programs is failing largely due to poor drug coverage (43.5%), poor patient compliance, and given the zoonotic nature of the disease, were bovines (e.g., cattle and water buffalos) act as a major reservoir of human infection. Bovines are presently not treated under the national control program.
In order to examine the issue of patient non-compliance to free MDA, we conducted a cross-sectional survey in 2015 on 2,189 adults (≥ 18 years of age) in the endemic province of Northern Samar, the Philippines using a structured survey questionnaire. 224 Barangay Health Workers (BHWs) were also studied at the village level given their direct contact with patients and their role in the coordination of MDA as advocates, implementers, and educators. BHWs were interviewed in order to determine if their knowledge of schistosomiasis and MDA were associated with achieving targeted compliance rates in their assigned barangays.
The overall rate of non-compliance to MDA in the last MDA round was 27%. Females (aOR=1.67, p=0.033) were more likely to be non-compliant. Respondents who believed that schistosomiasis was acquired by open defecation and poor sanitation (aOR=1.41, p=0.015), and by avoiding unclean drinking (aOR=2.09, p=0.001) were more likely to refuse treatment. Uncertainties on whether schistosomiasis can be treated (aOR=2.39, p=0.033), their fear of adverse reactions to praziquantel (aOR=1.94, p=0.021), misconceptions about alternative forms of treatment (aOR=1.45, p=0.037), and that praziquantel is used for purposes other than deworming (aOR=2.15, p=0.021) were all associated with a higher odds of non-compliance.
In contrary, being a farmer (aOR=0.62, p=0.038), participation in past MDA (aOR=0.30, p<0.001), informed about impending MDA (aOR=0.08, p<0.001), and having heard of schistosomiasis (aOR=0.22, p=0.045) were all significantly associated with reduced non-compliance.
BHWs showed good familiarity on how schistosomiasis was acquired and diagnosed. But both BHWs and residents had poor awareness of the signs and symptoms of schistosomiasis, disease prevention, and treatment options. There was no correlation between the knowledge scores of the BHWs and the residents (ρ = 0.080, p = 0.722). A Kruskal-Wallis analysis revealed significant differences in BHWs knowledge scores between the low (3.29, 95% CI 3.16-3.36), moderate (3.61, 95% CI 3.49-3.69) and high (4.05, 95% CI: 3.77-4.13) compliance village groups (p=0.002), with the high compliance areas having the highest mean knowledge score. This highlights the importance of community health workers in obtaining target coverage rates and improving patient compliance.
To improve national and global drug compliance to MDA for neglected tropical diseases there is an urgent need for intensive health education campaigns prior to conducting MDA that would not only provide disease specific information, but also deal with prevailing misconceptions about transmission, prevention, treatment, and drug side-effects. Investing in the development of community health workers with appropriate disease specific training and payment for their time is crucial if disease elimination is to be ultimately achieved.||