Title
Epidemiological characteristics of P. vivax asymptomatic infections in the Peruvian Amazon
Date Issued
31 August 2022
Access level
open access
Resource Type
journal article
Author(s)
Garcia Castillo S.S.
Guzman M.
Torres J.
Gomez J.
Garro K.
Cordova A.M.
Reategui C.
Abanto C.
Publisher(s)
Frontiers Media S.A.
Abstract
Introduction: Herein, we tested the hypothesis that Asymptomatic P. vivax (Pv) infected individuals (Asym) feature different epidemiological, clinical and biochemical characteristics, as well as hematological parameters, potentially predictive of clinical immunity in comparison to symptomatic Pv infected individuals (Sym). Methodology: Between 2018 - 2021, we conducted 11 population screenings (PS, Day 0 (D0)) in 13 different riverine communities around Iquitos city, in the Peruvian Amazon, to identify Pv Sym and Asym individuals. A group of these individuals agreed to participate in a nested case - control study to evaluate biochemical and hematological parameters. Pv Asym individuals did not present common malaria symptoms (fever, headache, and chills), had a positive/negative microscopy result, a positive qPCR result, reported no history of antimalarial treatment during the last month, and were followed-up weekly until Day 21 (D21). Control individuals, had a negative malaria microscopy and qPCR result, no history of antimalarial treatment or malaria infections during the last three years, and no history of comorbidities or chronic infections. Results: From the 2159 individuals screened during PS, data revealed a low but heterogeneous Pv prevalence across the communities (11.4%), where most infections were Asym (66.7%) and submicroscopic (82.9%). A total of 29 Asym, 49 Sym, and 30 control individuals participated in the nested case - control study (n=78). Ten of the individuals that were initially Asym at D0, experienced malaria symptoms during follow up and therefore, were included in the Sym group. 29 individuals remained Asym throughout all follow-ups. High levels of eosinophils were found in Asym individuals in comparison to Sym and controls. Conclusion: For the first-time, key epidemiological, hematological, and biochemical features are reported from Pv Asym infections from the Peruvian Amazon. These results should be considered for the design and reshaping of malaria control measures as the country moves toward malaria elimination.
Volume
12
Language
English
OCDE Knowledge area
Parasitología
Medicina tropical
Epidemiología
Subjects
Scopus EID
2-s2.0-85138176941
PubMed ID
Source
Frontiers in Cellular and Infection Microbiology
ISSN of the container
2235-2988
Sponsor(s)
We thank all residents and local authorities from the communities for their enthusiastic participation in the study, as well as all field workers for their dedication during the fieldwork. EV acknowledges the financial support of Proyecto Concytec – Banco Mundial “Mejoramiento y Ampliación de los Servicios del Sistema Nacional de Ciencia Tecnología e Innovación Tecnológica” 8682-PE, through its executing unit ProCiencia [08-2018-FONDECYT/BM-Programas de Doctorados en Áreas Estratégicas y Generales]. We thank Oscar Nolasco and Roberson Ramirez for their technical support for during qPCR experiments. We also thank logistic and administrative support of Rosa Alban, Yulissa Vasquez, and Yovana Maldonado from the Malaria Laboratory at UPCH.
This study received funding from the World Bank Group. The funder was not involved in the study design, collection, analysis, interpretation of data, the writing of this article or the decision to submit it for publication.
Funding for this study was provided by The International Centers of Excellence for Malaria Research (ICEMR) program (U19AI089681), NIH–USA; FOGARTY International Center (D43TW007120), NIH-USA. EV is supported by Proyecto Concytec – Banco Mundial “Mejoramiento y Ampliación de los Servicios del Sistema Nacional de Ciencia Tecnología e Innovación Tecnológica” 8682-PE, through its executing unit ProCiencia [08-2018-FONDECYT/BM-Programas de Doctorados en Áreas Estratégicas y Generales].
Sources of information:
Directorio de Producción Científica
Scopus