Social mobilisation, drug coverage and compliance and adverse reactions in a Mass Drug Administration (MDA) Programme for the Elimination of Lymphatic Filariasis in Sri Lanka

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A comparison of two tests for filarial antigenemia in areas in Sri Lanka and Indonesia with low-level persistence of lymphatic filariasis following mass drug administration

BACKGROUND: Filarial antigen tests are key tools for mapping the distribution of bancroftian filariasis and for detecting areas with persistent infections following mass drug administration (MDA). A recent study showed that the new Alere Filariasis Test Strip (FTS) has better analytical sensitivity than the BinaxNOW Filariasis card test (Card Test) for detecting circulating filarial antigen, and the FTS detected more positive results than the Card Test in a field study performed in a highly endemic area in Liberia. METHODS: The present study compared the performance of the FTS and the Card Test in community surveys that were conducted in southern Sri Lanka and in Indonesia (Central Java) in areas with low-level persistence of LF following multiple rounds of MDA with diethylcarbamazine plus albendazole. The studies were performed in densely populated semi-urban areas where Wuchereria bancrofti is transmitted by Culex quinquefasciatus. RESULTS: Antigenemia rates by FTS were 138 % higher in the Sri Lanka study (43/852 vs. 18/852) and 21 % higher in the Indonesia study (50/778 vs. 41/778) than antigenemia rates by Card Test. Antigenemia rates were significantly higher in males than in females and higher in adults than in children in both study sites. Although overall antigenemia rates and test scores were significantly higher by FTS than by Card Test in both study areas, rates in young children were similar with both tests in both areas. CONCLUSIONS: These results extend the previously reported superior sensitivity of the FTS to areas with low residual infection rates following MDA, and this could affect mapping and post-MDA survey results in adults. However, our findings suggest that results of transmission assessment surveys (TAS) performed in school-aged children are likely to be similar with both tests

Case report of Plasmodium ovale curtisi malaria in Sri Lanka: relevance for the maintenance of elimination status

Background: Following its recent certification as malaria-free, imported infections now pose the greatest threat for maintaining this status in Sri Lanka. Imported infections may also introduce species that are uncommon or not previously endemic to these areas. We highlight in this case report the increasing importance of less common malaria species such as Plasmodium ovale in elimination settings and discuss its relevance for the risk of malaria resurgence in the country. Case presentation: A 41-year-old patient from southern Sri Lanka was diagnosed with malaria after 8 days of fever. Microscopy of blood smears revealed parasites morphologically similar to P. vivax and the rapid diagnostic test was indicative of non-P. falciparum malaria. He was treated with chloroquine over 3 days and primaquine for 14 days. He was negative for malaria at a one-year follow-up. Molecular testing performed subsequently confirmed that infection was caused by P. ovale curtisi. The patient gave a history of P. vivax malaria treated with chloroquine and primaquine. He also provided a history of travel to malaria endemic regions, including residing in Liberia from May 2012 to November 2013, throughout which he was on weekly malaria prophylaxis with mefloquine. He had also visited India on an eight-day Buddhist pilgrimage tour in September 2014 without malaria prophylaxis. Conclusions: It is crucial that every case of malaria is investigated thoroughly and necessary measures taken to prevent re-introduction of malaria. Accurate molecular diagnostic techniques need to be established in Sri Lanka for the screening and diagnosis of all species of human malaria infections, especially those that may occur with low parasitemia and are likely to be undetected using the standard techniques currently in use. In addition, ascertaining whether an infection occurred through local transmission or by importation is critical in the implementation of an effective plan of action in the country. This new era emphasizes the global nature of regional malaria elimination. Increasing global surveillance and tool development are necessary in order to “fingerprint” parasites and identify their origin