TY - JOUR
T1 - Comprehensive assessment of a hotspot with persistent bancroftian filariasis in coastal Sri Lanka
AU - Rao, Ramakrishna U.
AU - Samarasekera, Sandhya D.
AU - Nagodavithana, Kumara C.
AU - Goss, Charles W.
AU - Punchihewa, Manjula W.
AU - Dassanayaka, Tharanga D.M.
AU - Ranasinghe, Udaya S.B.
AU - Mendis, Devika
AU - Weil, Gary J.
N1 - Publisher Copyright:
© Copyright 2018 by The American Society of Tropical Medicine and Hygiene.
PY - 2018
Y1 - 2018
N2 - The Sri Lankan Anti-Filariasis campaign distributed five rounds of mass drug administration (MDA with diethylcarbamazine plus albendazole) to some 10 million people in eight districts between 2002 and 2006. Sri Lanka was recognized bythe WHO for having eliminated lymphatic filariasis (LF) as apublic health problem in 2016. However, recent studies by our group documented pockets with persistent LF in coastal Sri Lanka, especially in Galle district. The present study was performed to reexamine an area previously identified as a potential hotspot for persistent LF (Balapitiya Public Health Inspector area, population 17, 500). A community survey documented high rates for circulating filarial antigenemia (3%, confidence interval [CI]: 1.8-4.9) and microfilaremia (1%, CI: 0.5-2.5%). Circulating filarial antigenemia rates were 2.8-fold higher in males than females. High prevalence was also observed for anti-filarial antibodies in young children (5.7%, CI: 3.7-8.4%) and for filarial DNA in vector mosquitoes (5.2%, CI: 4.2-6.3%). Spatial data showed that persistent LF was dispersed across the entire study area. Other studies showed that persistent LF was not limited to Balapitiya and not solved by additional rounds of MDA. Molecular xenomonitoring studies conducted in 2016 in 22 of 168 Public Health Midwife areas in the coastal Galle evaluation unit (approximate population 600,000) found that 179 of 660 (27%) pools of Culex collected from all areas were positive for Wuchereria bancrofti DNA by quantitative polymerase chain reaction; the estimated infection rate in mosquitoes was 1.26%, CI: 1.0-1.5%. Interventions other than routine MDA will be required to remove LF hotspots in Balapitiya and in other areas in coastal Sri Lanka.
AB - The Sri Lankan Anti-Filariasis campaign distributed five rounds of mass drug administration (MDA with diethylcarbamazine plus albendazole) to some 10 million people in eight districts between 2002 and 2006. Sri Lanka was recognized bythe WHO for having eliminated lymphatic filariasis (LF) as apublic health problem in 2016. However, recent studies by our group documented pockets with persistent LF in coastal Sri Lanka, especially in Galle district. The present study was performed to reexamine an area previously identified as a potential hotspot for persistent LF (Balapitiya Public Health Inspector area, population 17, 500). A community survey documented high rates for circulating filarial antigenemia (3%, confidence interval [CI]: 1.8-4.9) and microfilaremia (1%, CI: 0.5-2.5%). Circulating filarial antigenemia rates were 2.8-fold higher in males than females. High prevalence was also observed for anti-filarial antibodies in young children (5.7%, CI: 3.7-8.4%) and for filarial DNA in vector mosquitoes (5.2%, CI: 4.2-6.3%). Spatial data showed that persistent LF was dispersed across the entire study area. Other studies showed that persistent LF was not limited to Balapitiya and not solved by additional rounds of MDA. Molecular xenomonitoring studies conducted in 2016 in 22 of 168 Public Health Midwife areas in the coastal Galle evaluation unit (approximate population 600,000) found that 179 of 660 (27%) pools of Culex collected from all areas were positive for Wuchereria bancrofti DNA by quantitative polymerase chain reaction; the estimated infection rate in mosquitoes was 1.26%, CI: 1.0-1.5%. Interventions other than routine MDA will be required to remove LF hotspots in Balapitiya and in other areas in coastal Sri Lanka.
UR - http://www.scopus.com/inward/record.url?scp=85053054455&partnerID=8YFLogxK
U2 - 10.4269/ajtmh.18-0169
DO - 10.4269/ajtmh.18-0169
M3 - Article
C2 - 30014812
AN - SCOPUS:85053054455
SN - 0002-9637
VL - 99
SP - 735
EP - 742
JO - American Journal of Tropical Medicine and Hygiene
JF - American Journal of Tropical Medicine and Hygiene
IS - 3
ER -