A first nation-wide assessment of soil-transmitted helminthiasis in Fijian primary schools, and factors associated with the infection, using a lymphatic filariasis transmission assessment survey as surveillance platform.

BACKGROUND: Soil-transmitted helminthiasis (STH) is endemic in Fiji but its prevalence is not known and likely to have changed after a decade of mass drug administration (MDA) for lymphatic filariasis (LF). By linking with LF transmission assessment surveys (LF-TAS), we undertook the first nation-wide assessment of STH in Fijian primary schools, as well as an analysis of factors associated with STH infections. METHODOLOGY/PRINCIPAL FINDINGS: A cross-sectional assessment for STH was conducted in all four Divisions of Fiji from 2014 to 2015. In the Western, Central, and Northern Divisions, schools were sub-sampled after LF-TAS, while, in the Eastern Division, schools were selected via simple random sampling. For the diagnosis of STH, stool samples were examined by coproscopy with a single Kato-Katz thick smear (KK) and the formol-ether-acetate concentration technique, except for the samples from the Eastern Division where only KK was used. Mean prevalence of any STH among class 1-2 students at the national level was 10.5% (95% CI: 6.9-15.5). Across the three Divisions via LF-TAS, the prevalence levels for ascariasis were 8.7% (95% CI: 4.3-16.6), hookworm 3.9% (95% CI: 2.3-6.6) and trichuriasis 0%. In the Eastern Division, ascariasis prevalence was 13.3% (95% CI: 6.4-25.6), and hookworm 0.7% (95% CI: 0.2-2.5), with one case of trichuriasis. Among class 3-8 students, ascariasis prevalence was lower. Lower risk of any STH was associated with wearing shoes (adjusted OR 0.54, 95% CI: 0.32-0.90) and having piped water from the Fiji Water Authority at home (adjusted OR 0.48, 95% CI: 0.25-0.92). CONCLUSIONS: After a decade of community-based LF-MDA, STH in school-age children in Fiji is now close to 10%, but localities of endemicity remain. Preventive chemotherapy should be maintained in areas with elevated STH prevalence alongside targeted delivery of integrated WASH interventions. LF-TAS has provided an opportunity to develop future public health surveillance platforms.

Island-Wide Surveillance of Gastrointestinal Protozoan Infection on Fiji by Expanding Lymphatic Filariasis Transmission Assessment Surveys as an Access Platform.

As part of lymphatic filariasis (LF) transmission assessment surveys (TAS) on Fiji, an island-wide assessment of gastrointestinal protozoan infection was performed by inspection of a concomitant stool sample collection to investigate the distribution of parasitic protozoa. All grade 1 and 2 students of 69 schools on the two main islands were targeted in two phases (one in the Western Division and the other in the Central and Northern Divisions, except Taveuni sub-Division of Northern), where fecal samples of 1,800 students were available for coproscopy using formalin-ether-acetate concentration. The overall prevalence of Giardia infection was 1.6%, having 2.2% in Western and 0.8% in Central/Northern Divisions (P = 0.094). The school-level prevalence of giardiasis ranged from 0% to 15.4%, and hotspot analysis using the Getis-Ord Gi* method detected spatial heterogeneity of giardiasis prevalence in schools around Lautoka (Z-score = 3.36, P value < 0.05), an area affected by Cyclone Kofi in February 2014. Any protozoan infection prevalence was 4.9% in Western and 4.4% in Central/Northern Divisions (P = 0.825). Real-time polymerase chain reaction analysis to confirm the findings from a parasitological examination of a 10% stool archive in 95% ethanol from Western Division revealed an elevated prevalence of giardiasis up to 22.4%, the presence of Entamoeba histolytica, and the absence of Cryptosporidium parvum. Obtaining stool samples alongside LF TAS is a convenient access platform for cosurveillance of gastrointestinal protozoan infection and has pinpointed hitherto unknown hotspots of giardiasis in urban city centers of Fiji. This calls for greater attention to apply tailored water, sanitation and hygiene measures for the control of these parasites.