Impact of mass drug administration for elimination of lymphatic filariasis in Nepal

Abstract

BackgroundLymphatic filariasis (LF) is a neglected tropical disease transmitted by mosquitoes. Nepal has implemented a national effort to eliminate LF by 2020 through mass drug administration (MDA) using diethylcarbamazine (DEC) and albendazole (ALB). We assessed the impact of MDAs on LF in selected districts of Nepal after the recommended six MDA rounds had been completed.Methodology and principal findingsBaseline surveys were conducted in seven districts and mapping data were used as baseline in the other three districts before starting MDA in 2009. LF antigen (Ag) prevalence ranged from 1.06% to 20% among districts included in the baseline and mapping study. The number of people who received DEC and ALB were recorded during each MDA round and population-based cluster surveys were conducted at least once in each district during the life of the program. The reported MDA coverage in five districts was consistently at least 65%. Two districts achieved the targeted coverage in four out of five rounds and the rest three districts achieved the target only in the first round. A pre-transmission assessment survey (pre-TAS) was conducted in one sentinel site and at least one spot check site in each of the districts after five MDA rounds. In pre-TAS, all the sites of five districts (Pyuthan, Arghakhanchi, Kaski, Bhaktapur, and Kathmandu) and all but one spot check site of Lalitpur district had LF Ag < 2% (ranging from 0.0% to 1.99%). Transmission assessment survey (TAS) was conducted in six evaluation units (EUs) consisting of six districts qualified on pre-TAS. Though MDA coverage of 65% was not achieved in three districts (Kathmandu, Lalitpur and Bhaktapur), Nepal government in consultation with World Health Organization (WHO) decided to conduct TAS. All six EUs achieved the LF Ag threshold required to stop MDA in TAS, despite the low reported MDA coverage in those three districts.ConclusionsAlthough Nepal has achieved significant progress towards LF elimination, five rounds of MDA were not sufficient to disrupt the transmission cycle in all districts, probably because of high baseline prevalence.

An Overview of Microfilariae on Patients who have received treatment in Batuah Village, Kotawaringin Timur District 2015

“…14 Control of filariasis vector is a series of activities in filariasis elimination, so the identification of mosquitoes as filariasis vectors needs to be done simultaneously. 15 Vector control can be applied in various ways, including spraying, larvacides, use of mosquito nets, repellent use and environmental manipulation. 14,15 The environmental manipulation in Batuah Village is impossible, due to the social condition of the community and the income source of the community in the form of plantations.…”

“…So, they feel they do not have to take medicine; this is due to lack of information from the officers about the importance of this mass treatment so as not to be attention is important to society. 15 According to the document from Ministry of Health 2012 on Determination of Termination of Drug Prevention Prevention of Filariasis, if still found positive results in the examination of capillary blood samples in a region then the mass treatment should be continued. Although the microfilaria rate in Batuah Village is now less than 1%, mass treatment should still be done because there is still a positive result of filariasis which is feared will occur transmission through filariasis vector mosquito that may bite the patient who still positive filariasis.…”

A broad insight onto the distribution pattern of Dirofilaria immitis in community dogs in Nepal

“…and are crucial for the larval development of microfilariae into L3 and their transmission [27][28][29][30], no information is reported on the species involved into the circulation of these parasites within the Indo-Nepal region. Nevertheless, mosquitoes are active in this area, as it can be inferred from the efforts spent on the control and epidemiological surveillance of other vector-borne diseases, such as Dengue, Zika or other human filarial worms [30][31][32].…”

Changing Trend of Infectious Diseases in Nepal

“…As a result, LF has shown a declining trend during recent years. However, five rounds of MDA were not sufficient to disrupt the transmission cycle in all Districts, probably because high baseline prevalence has posed as a challenge [69].…”