Biology, distribution and control of Anopheles (Cellia) minimus in the context of malaria transmission in northeastern India.

Vas Dev,Sylvie Manguin

doi:10.1186/s13071-016-1878-6

Abstract

Among six dominant mosquito vector species involved in malaria transmission in India, Anopheles minimus is a major species in northeast India and held responsible for focal disease outbreaks characterized by high-rise of Plasmodium falciparum infections and attributable death cases. It has been now genetically characterized that among the three-member species of the Minimus Complex spread in Asia, An. minimus (former species A) is prevalent in India including northeastern states and east-central state of Odisha. It is recorded in all seasons and accounts for perennial transmission evidenced by records of sporozoite infections. This species is highly anthropophilic, and largely endophilic and endophagic, recorded breeding throughout the year in slow flowing seepage water streams. The populations of An. minimus in India are reported to be highly diverse indicating population expansion with obvious implications for judicious application of vector control interventions. Given the rapid ecological changes due to deforestation, population migration and expansion and developmental activities, there is scope for further research on the existence of potential additional sibling species within the An. minimus complex and bionomics studies on a large geographical scale for species sanitation. For control of vector populations, DDT continues to be applied on account of retaining susceptibility status even after decades of residual spraying. Anopheles minimus is a highly adaptive species and requires continuous and sustained efforts for its effective control to check transmission and spread of drug-resistant malaria. Anopheles minimus populations are reportedly diminishing in northeastern India whereas it has staged comeback in east-central State of Odisha after decades of disappearance with its eco-biological characteristics intact. It is the high time to siege the opportunity for strengthening interventions against this species for its population diminution to sub-optimal levels for reducing transmission in achieving malaria elimination by target date of 2030.

Highlights

In the recent past, with the development of aided tools of molecular systematics, there have been significant advances in our understanding of malaria vector species and disease relationships [1, 2]
We report the available and most recent information on the systematic position of An. minimus, its bionomical characteristics and distribution in India to help formulate species-specific control strategies to reduce transmission in space and time
It was observed that given the population diminution in human dwellings, An. minimus continued to breed in seepage water streams but adult mosquitoes had shifted resting habitat outdoors (Dev, unpublished observations)

Summary

Introduction

With the development of aided tools of molecular systematics, there have been significant advances in our understanding of malaria vector species and disease relationships [1, 2]. In northeast India, An. minimus is reported to occur in Assam, Arunachal Pradesh, Meghalaya, Nagaland and Tripura [50, 51] and in eastern State of Odisha [28]. Bionomical characteristics Seasonal prevalence and resting habitat Anopheles minimus is characteristically a species of the forested hills and foothill valley areas in most areas of Southeast Asia and India [20, 30, 36, 54].

Results

Conclusion