Improving current helminth control strategies: Lessons from a baseline prevalence survey of soil-transmitted helminth infections in adolescent females and pregnant women in selected local government units in the Philippines

OBJECTIVES: This study utilized a cross-sectional study design to determine the prevalence and intensity of STH infections among adolescent females and pregnant women, to describe the nutritional status of the two population groups in selected study sites in the Philippines, and to propose a scheme for classification of endemic sites as basis for conduct of control strategies. METHODS: Parasitologic assessment was conducted through examination of collected stool samples using the Kato-Katz technique, while nutritional status was assessed through primary height and weight measurements.RESULTS: Results of the parasitologic assessment in adolescent females showed an overall cumulative prevalence of 30.4% (12.5% - 61.8%) and a prevalence of heavy intensity infection of 7.9% (0.7% - 22.6%). In pregnant women, overall cumulative prevalence was 31.5% (13.2% - 75.8%) and prevalence of heavy intensity infection was 10.2% (0.9%- 39.6%). CONCLUSION: Significant differences in prevalence in the different sentinel sites suggest the need to consider a modified classification scheme for endemic communities to determine the most cost-effective strategies for morbidity control. The utilization of this classification scheme alongside regular sentinel surveillance will help validate the scheme and contribute towards the development of more appropriate program guidelines for nationwide implementation.

Impact of a local government unit supported school-based initiative for control of intestinal helminth infections

Objectives. This study aimed to describe baseline and follow-up prevalence and intensity of soil-transmitted helminth (STH) infections, nutritional status and school performance of school-age children in Cebu City. By measuring these parameters, it also aimed to monitor the progress of a local government unit-led, school-based, schoolteacher-assisted deworming initiative. Methods. Grade three and grade four pupils from two selected school districts in Cebu City were chosen as participants. Kato-Katz technique was used to assess helminth infections. All positive slides and 10% of all negative slides were re-examined blindly by a reference microscopist for quality control. Secondary anthropometric and school performance data were also obtained from the Department of Education. Results. Baseline results showed cumulative prevalence and prevalence of heavy intensity infection of 73.1% and 44.3%, respectively, which were significantly lower during follow-up at 56.5% (p < 0.0001) and 26.5% (p < 0.0001), respectively. School performance improved in District B, with an 8.8% increase in mean percentage score from baseline to follow-up. There was no marked difference between baseline and follow-up proportions of pupils with below normal weight-for-age and height-for-age. Conclusions. The positive results merit continuation of the school-based STH control initiative in Cebu City. Improvements in water supply and sanitation, promotion of good hygiene and health education are important in minimizing risks of infection and re-infection.