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The burden of submicroscopic and asymptomatic malaria in India revealed from epidemiology studies at three varied transmission sites in India.

ABSTRACT: Malaria in India, while decreasing, remains a serious public health problem, and the contribution of submicroscopic and asymptomatic infections to its persistence is poorly understood. We conducted community surveys and clinic studies at three sites in India differing in their eco-epidemiologies: Chennai (Tamil Nadu), Nadiad (Gujarat), and Rourkela (Odisha), during 2012-2015. A total of 6,645 subject blood samples were collected for Plasmodium diagnosis by microscopy and PCR, and an extensive clinical questionnaire completed. Malaria prevalence ranged from 3-8% by PCR in community surveys (24 infections in Chennai, 56 in Nadiad, 101 in Rourkela), with Plasmodium vivax dominating in Chennai (70.8%) and Nadiad (67.9%), and Plasmodium falciparum in Rourkela (77.3%). A proportional high burden of asymptomatic and submicroscopic infections was detected in community surveys in Chennai (71% and 71%, respectively, 17 infections for both) and Rourkela (64% and 31%, 65 and 31 infections, respectively). In clinic studies, a proportional high burden of infections was identified as submicroscopic in Rourkela (45%, 42 infections) and Chennai (19%, 42 infections). In the community surveys, anemia and fever were significantly more common among microscopic than submicroscopic infections. Exploratory spatial analysis identified a number of potential malaria hotspots at all three sites. There is a considerable burden of submicroscopic and asymptomatic malaria in malarious regions in India, which may act as a reservoir with implications for malaria elimination strategies.

SUBMITTER: van Eijk AM

PROVIDER: S-EPMC6863831 | biostudies-literature | 2019 Nov

REPOSITORIES: biostudies-literature

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The burden of submicroscopic and asymptomatic malaria in India revealed from epidemiology studies at three varied transmission sites in India.

van Eijk Anna Maria AM Sutton Patrick L PL Ramanathapuram Lalitha L Sullivan Steven A SA Kanagaraj Deena D Priya G Sri Lakshmi GSL Ravishankaran Sangamithra S Asokan Aswin A Sangeetha V V Rao Pavitra N PN Wassmer Samuel C SC Tandel Nikunj N Patel Ankita A Desai Nisha N Choubey Sandhya S Ali Syed Zeeshan SZ Barla Punam P Oraon Rajashri Rani RR Mohanty Stuti S Mishra Shobhna S Kale Sonal S Bandyopadhyay Nabamita N Mallick Prashant K PK Huck Jonathan J Valecha Neena N Singh Om P OP Pradhan K K Singh Ranvir R Sharma S K SK Srivastava Harish C HC Carlton Jane M JM Eapen Alex A

Scientific reports 20191119 1

Malaria in India, while decreasing, remains a serious public health problem, and the contribution of submicroscopic and asymptomatic infections to its persistence is poorly understood. We conducted community surveys and clinic studies at three sites in India differing in their eco-epidemiologies: Chennai (Tamil Nadu), Nadiad (Gujarat), and Rourkela (Odisha), during 2012-2015. A total of 6,645 subject blood samples were collected for Plasmodium diagnosis by microscopy and PCR, and an extensive cl ...[more]

PMID: 31745160

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The burden of submicroscopic and asymptomatic malaria in India revealed from epidemiology studies at three varied transmission sites in India.

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The burden of submicroscopic and asymptomatic malaria in India revealed from epidemiology studies at three varied transmission sites in India.

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