Many trials have explored the efficacy of individual drugs and drug combinations to treat bancroftian filariasis. This narrative review summarizes the current evidence for drug management of bancroftian filariasis. Diethylcarbamazine (DEC) remains the prime antifilarial agent with a well-established microfilaricidal and some macrofilaricidal effects. Ivermectin (IVM) is highly microfilaricidal but minimally macrofilaricidal. The role of albendazole (ALB) in treatment regimens is not well established though the drug has a microfilaricidal effect. The combination of DEC+ALB has a better long-term impact than IVM+ALB. Recent trials have shown that doxycycline therapy against Wolbachia, an endosymbiotic bacterium of the parasite, is capable of reducing microfilaria rates and adult worm activity. Followup studies on mass drug administration (MDA) are yet to show a complete interruption of transmission, though the infection rates are reduced to a very low level. 1. Introduction There are nine filarial nematodes causing disease in humans. According to the location of the parasite and the pathogenesis, the disease can be classified as lymphatic, subcutaneous, and serous cavity filariasis. Two filarial worms, namely, Wuchereria bancrofti and Brugia malayi cause lymphatic filariasis. The World Health Organization (WHO) considers lymphatic filariasis to be a global health problem affecting approximately 120 million people in over 80 countries [1]. One-third of affected individuals are from South Asia and another one third is from Africa [1]. One sixth of the world population is at risk of infection [1]. The adult W. bancrofti worms live within the human lymphatic system. They have a long life span of 4–6 years. Females are viviparous and release thousands of microfilaria into the blood stream of the host after mating. These are taken up by vector mosquitoes during feeding, and the parasite undergoes several moults within the intermediate host to become the L3 larva which is the infective stage. During a feed, this larva enters the human blood stream and migrates to the lymphatics where it moults to become an adult worm [2]. There is a range of clinical manifestations in bancroftian filariasis with asymptomatic microfilaremics being at one end of the spectrum. Symptomatic patients may have acute (lymphangitis, lymphadenitis), chronic (elephantiasis, lymphoedema, hydrocoele, chyluria), or atypical (funiculitis, mastitis) manifestations [3]. Some may suffer from tropical pulmonary eosinophilia (TPE) due to the immunological hyperresponsiveness to the parasite [4].
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