Occurrence of Lymphatic Filariasis infection after 15 years of mass drug administration in two hotspot districts in the Upper East Region of Ghana

Abstract

Background Lymphatic filariasis (LF) causes chronic morbidity, which usually manifests as lymphedema or hydrocele. Mass drug administration (MDA) began in Kassena Nankana East Municipal (KNEM) and Nabdam, two hotspot districts in the Upper East Region in Ghana, in 2000 and 2005, respectively. This cross-sectional study evaluated the impact of 15 years of MDA on the control of LF as determined by circulating filarial antigen (CFA) and microfilariae assessment in the KNEM and the Nabdam districts. Methodology/Principal findings A total of 7,453 participants from eight sub-districts in the two hotspot districts (KNEM: N = 4604; Nabdam: N = 2849) were recruited into the study. The overall CFA prevalence as determined by the FTS was 19.6% and 12.8% in the KNEM and Nabdam districts, respectively. Manyoro, a sub-district on the border with Burkina Faso, recorded the highest CFA prevalence of 26% in the KNEM. Assessment of microfilariae and Og4C3 antigen was done from 1009 (KNEM: N = 799 (79.2%); Nabdam: N = 210 (20.8%)) randomly selected FTS-positive (N = 885) and FTS-negative (N = 124) individuals. The Og4C3 antigen was found in 22.6%/23.0% of the selected individuals (KNEM/Nabdam), whereas the night blood revealed microfilariae in only 0.7%/0.5%. Conclusions/Significance Using the WHO endorsed FTS, CFA prevalence exceeded the long-standing <2% threshold—which may need revision and validation. Surprisingly, the Og4C3 ELISA showed positive results in only about one-fifth of the FTS positive samples. However, even this result would not have met the <2% CFA criteria for LF elimination. In contrast, projections from the microfilariae results revealed a halt in LF transmission. The global elimination target was due in 2020 but has been extended to 2030 since this could not be met. Focused MDA intervention intensification on seasonal migrants and non-compliers, and implementation of alternative treatment strategies may suffice for the elimination of the disease.

Ghana’s path towards eliminating lymphatic filariasis

“…The GFEP administered an annual MDA of 150 μg/kg ivermectin and 400 mg albendazole through community-directed treatment for countries co-endemic with LF and onchocerciasis [ 28 , 29 ]. This initiative started in 10 districts and expanding annually from 2000 to 2006 [ 21 , 27 , 30 ] (Fig. 2 ).…”

Inhibitory activity of hydroalcoholic extract of Anancardium occidentale L. leaves against Brugia malayi hexokinase, a target for anti-filarial drug development

“…Possible reasons could be problems of drug coverage and consumption, operational issues, or drug resistance by the parasite. Among the two drugs administered, DEC has micro laricidal activity and not macro laricidal activity and hence adult parasites continue to produce micro lariae which will sustain the transmission [19]. Resistance to albendazole by several veterinary parasites has been reported earlier and larial parasites in the hot spots may have developed resistance.…”

Knowledge and perceptions of lymphatic filariasis patients in selected hotspot endemic communities in southern Ghana

“…The MDA program was initially rolled out in Ghana in 2000, with a second phase focused on endemic areas beginning in 2006 [ 7 ]. Despite this wide-spread program, there are still reports of microfilaria prevalence above the threshold for control in Ghana, < 2% [ 7 , 8 ]. After 15 years of MDA with an average of 11 rounds of treatment, there are still communities in Ghana with microfilaria prevalence as high as 5.6% [ 7 ].…”