A randomized community trial on safety and efficacy of co-administration of albendazole and ivermectin on lymphatic filariasis and its secondary effects on geohelminths in zanzibar.

Abstract

From November 1999 to February 2000 a community survey was carried out in the south district - Zanzibar and a total of 2839 individuals were screened. The purpose of this survey was (apart from detecting the magnitude and intensity of bancroftian filariasis and geohelminth infections) to determine safety and efficacy of co- administration of albendazole and Ivermectin on lymphatic filariasis and its secondary benefits on geohelminth and related factors in a sampled population in Unguja Island Zanzibar. A sample of 418 participants positive for bancroftian filariasis and or with clinical filarial disease were recruited. Pre and post treatment levels of microfilaria were determined by night blood sample collection and geohelminth infection was determined indirectly by egg counts. Out of these 418,259 (62%) were found to have at least one specie of geohelminth infection. These were physically examined and were randomly assigned to the two treatment aIDlS (ivermectin -albendazole or ivermectin placebo) and followed for 96 hours to monitor for any drug related side effects. Those who developed side effects were managed accordingly. Results showed that the overall prevalence of bancroftian filariasis and geohelminth was 13.7% and 44.7% respectively. The overall reduction on percentage and intensity of bancroftian filariasis and geohelminth infections were found to be higher in ivermectin-albendazole treatment arm (100% and 78.4% respectively) compared to ivermectin -placebo regime (reduced lymphatic and geohelminth by 97.8% and

Vll! 45.83 % respectively). Similar levels of reductions were noted on infections with different geohelminth species. Side effects were reported from six hours after drug administration reaching peak at 24 hours and declined from 72 hours. Headache and changes in respiratory rates were the major side effects associated with ivermectin -albendazole arm while high fever and dizziness were associated with ivermectin -placebo treatment regime. In conclusion, at short-term observation, the ivermectin -albendazole combination was noted to be more efficacious and safe in treatment of both parasites than ivennectin placebo regime. It is recommended that a long term evaluation on sustainability of these reduced parasites levels are conducted at three and six months respectively.