#Dengue and #chikungunya among outpatients with acute undifferentiated #fever in #Kinshasa, #DRC: A cross-sectional study (PLoS Negl Trop Dis., abstract)

[Source: PLoS Neglected Tropical Diseases, full page: (LINK). Abstract, edited.]

OPEN ACCESS /  PEER-REVIEWED / RESEARCH ARTICLE

Dengue and chikungunya among outpatients with acute undifferentiated fever in Kinshasa, Democratic Republic of Congo: A cross-sectional study

Sam Proesmans , Freddy Katshongo, John Milambu, Blaise Fungula, Hypolite Muhindo Mavoko, Steve Ahuka-Mundeke, Raquel Inocêncio da Luz, Marjan Van Esbroeck, Kevin K. Ariën, Lieselotte Cnops, Birgit De Smet, Pascal Lutumba, Jean-Pierre Van geertruyden, Veerle Vanlerberghe

Published: September 5, 2019 / DOI: https://doi.org/10.1371/journal.pntd.0007047 / This is an uncorrected proof.

 

Abstract

Background

Pathogens causing acute fever, with the exception of malaria, remain largely unidentified in sub-Saharan Africa, given the local unavailability of diagnostic tests and the broad differential diagnosis.

Methodology

We conducted a cross-sectional study including outpatient acute undifferentiated fever in both children and adults, between November 2015 and June 2016 in Kinshasa, Democratic Republic of Congo. Serological and molecular diagnostic tests for selected arboviral infections were performed on blood, including PCR, NS1-RDT, ELISA and IFA for acute, and ELISA and IFA for past infections.

Results

Investigation among 342 patients, aged 2 to 68 years (mean age of 21 years), with acute undifferentiated fever (having no clear focus of infection) revealed 19 (8.1%) acute dengue–caused by DENV-1 and/or DENV-2 –and 2 (0.9%) acute chikungunya infections. Furthermore, 30.2% and 26.4% of participants had been infected in the past with dengue and chikungunya, respectively. We found no evidence of acute Zika nor yellow fever virus infections. 45.3% of patients tested positive on malaria Rapid Diagnostic Test, 87.7% received antimalarial treatment and 64.3% received antibacterial treatment.

Discussion

Chikungunya outbreaks have been reported in the study area in the past, so the high seroprevalence is not surprising. However, scarce evidence exists on dengue transmission in Kinshasa and based on our data, circulation is more important than previously reported. Furthermore, our study shows that the prescription of antibiotics, both antibacterial and antimalarial drugs, is rampant. Studies like this one, elucidating the causes of acute fever, may lead to a more considerate and rigorous use of antibiotics. This will not only stem the ever-increasing problem of antimicrobial resistance, but will–ultimately and hopefully–improve the clinical care of outpatients in low-resource settings.

Trial registration ClinicalTrials.gov NCT02656862.

 

Author summary

Malaria remains one of the most important causes of fever in sub-Saharan Africa. However, its share is declining, since the diagnosis and treatment of malaria have improved significantly over the years. Hence leading to an increase in the number of patients presenting with non-malarial fever. Often, obvious clinical signs and symptoms like cough or diarrhea are absent, probing the question: “What causes the fever?” Previous studies have shown that the burden of arboviral infections–like dengue and chikungunya–in sub-Saharan Africa is underestimated, which is why we screened for four common arboviral infections in patients presenting with ‘undifferentiated fever’ at an outpatient clinic in suburban Kinshasa, Democratic Republic of Congo. Among the patients tested, we found that one in ten presented with an acute arboviral infection and that almost one in three patients had been infected in the past. These findings suggest that clinicians should think about arboviral infections more often, thereby refraining from the prescription of antibiotics, a practice increasingly problematic given the global rise of antimicrobial resistance.

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Citation: Proesmans S, Katshongo F, Milambu J, Fungula B, Muhindo Mavoko H, Ahuka-Mundeke S, et al. (2019) Dengue and chikungunya among outpatients with acute undifferentiated fever in Kinshasa, Democratic Republic of Congo: A cross-sectional study. PLoS Negl Trop Dis 13(9): e0007047. https://doi.org/10.1371/journal.pntd.0007047

Editor: Stuart D. Blacksell, Mahidol Univ, Fac Trop Med, THAILAND

Received: November 28, 2018; Accepted: August 6, 2019; Published: September 5, 2019

Copyright: © 2019 Proesmans et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Data Availability: All relevant data are within the manuscript and its Supporting Information files.

Funding: This study was co-funded by the framework agreement between the Institute of Tropical Medicine and the Belgian development cooperation (https://www.itg.be/E/cooperation) to VV and Vlaamse Interuniversitaire Raad – Universitaire Ontwikkelingssamenwerking (https://www.vliruos.be/en) (VLIR-UOS, Grant reference ZRDC2014MP083) to JPVG. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Competing interests: The authors have declared that no competing interests exist.

Keywords: Arbovirus; Dengue fever; Chikungunya fever; Malaria; Serology; Seroprevalence; DRC.

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#Sindbis virus #polyarthritis #outbreak signalled by virus prevalence in the #mosquito vectors (PLoS Negl Trop Dis., abstract)

[Source: PLoS Neglected Tropical Diseases, full page: (LINK). Abstract, edited.]

OPEN ACCESS /  PEER-REVIEWED / RESEARCH ARTICLE

Sindbis virus polyarthritis outbreak signalled by virus prevalence in the mosquito vectors

Jan O. Lundström , Jenny C. Hesson, Martina L. Schäfer, Örjan Östman, Torsten Semmler, Michaël Bekaert, Manfred Weidmann, Åke Lundkvist, Martin Pfeffer

Published: August 29, 2019 / DOI: https://doi.org/10.1371/journal.pntd.0007702 / This is an uncorrected proof.

 

Abstract

Polyarthritis and rash caused by Sindbis virus (SINV), was first recognised in northern Europe about 50 years ago and is known as Ockelbo disease in Sweden and Pogosta disease in Finland. This mosquito-borne virus occurs mainly in tropical and sub-tropical countries, and in northern Europe it is suggested to cause regularly reoccurring outbreaks. Here a seven-year cycle of SINV outbreaks has been referred to in scientific papers, although the hypothesis is based solely on reported human cases. In the search for a more objective outbreak signal, we evaluated mosquito abundance and SINV prevalence in vector mosquitoes from an endemic area in central Sweden. Vector mosquitoes collected in the River Dalälven floodplains during the years before, during, and after the hypothesised 2002 outbreak year were assayed for virus on cell culture. Obtained isolates were partially sequenced, and the nucleotide sequences analysed using Bayesian maximum clade credibility and median joining network analysis. Only one SINV strain was recovered in 2001, and 4 strains in 2003, while 15 strains were recovered in 2002 with significantly increased infection rates in both the enzootic and the bridge-vectors. In 2002, the Maximum Likelihood Estimated infection rates were 10.0/1000 in the enzootic vectors Culex torrentium/pipiens, and 0.62/1000 in the bridge-vector Aedes cinereus, compared to 4.9/1000 and 0.0/1000 in 2001 and 0.0/1000 and 0.32/1000 in 2003 Sequence analysis showed that all isolates belonged to the SINV genotype I (SINV-I). The genetic analysis revealed local maintenance of four SINV-I clades in the River Dalälven floodplains over the years. Our findings suggest that increased SINV-I prevalence in vector mosquitoes constitutes the most valuable outbreak marker for further scrutinising the hypothesized seven-year cycle of SINV-I outbreaks and the mechanisms behind.

 

Author summary

The mosquito-borne Sindbis virus (SINV) causes polyarthritis and rash known as Ockelbo disease in Sweden and Pogosta disease in Finland. This mainly tropical and sub-tropical virus occurs in many countries, and in northern Europe it is suggested to cause reoccurring outbreaks every seventh year. The seven-year SIN outbreak cycle is commonly referred to in scientific papers, although the hypothesis is based solely on reported clinical cases. In the search for a more objective outbreak risk signal, we evaluated abundance and SINV prevalence in vector mosquitoes from Sweden. Vector mosquitoes collected in the River Dalälven floodplains the years before, during and after the hypothesized 2002 outbreak, were assayed for SINV. SINV prevalence was significantly increased in vector mosquitoes during the hypothesized 2002 outbreak, as compared to the 2001 pre-outbreak and the 2003 post-outbreak years. Genetic analysis showed a close relationship between the virus strains, indicating SINV has remained in local annual enzootic circulation since been introduced into the River Dalälven floodplains. We conclude that increased SINV prevalence in vector mosquitoes constitutes a marker most valuable for studying the seven-year outbreak cycle.

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Citation: Lundström JO, Hesson JC, Schäfer ML, Östman Ö, Semmler T, Bekaert M, et al. (2019) Sindbis virus polyarthritis outbreak signalled by virus prevalence in the mosquito vectors. PLoS Negl Trop Dis 13(8): e0007702. https://doi.org/10.1371/journal.pntd.0007702

Editor: Jason L. Rasgon, The Pennsylvania State University, UNITED STATES

Received: August 29, 2018; Accepted: August 13, 2019; Published: August 29, 2019

Copyright: © 2019 Lundström et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

Data Availability: All relevant data are within the paper and its Supporting Information files.

Funding: The author(s) received no specific funding for this work.

Competing interests: The authors have declared that no competing interests exist.

Keywords: Arbovirus; Sindbis virus; Polyarthritis; Sweden; Finland; Mosquitoes.

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#Clinical #relevance of #Zika #symptoms in the context of a #Zika #Dengue #epidemic (J Infect Public Health, abstract)

[Source: US National Library of Medicine, full page: (LINK). Abstract, edited.]

J Infect Public Health. 2019 Aug 6. pii: S1876-0341(19)30240-0. doi: 10.1016/j.jiph.2019.07.006. [Epub ahead of print]

Clinical relevance of Zika symptoms in the context of a Zika Dengue epidemic.

Guanche Garcell H1, Gutiérrez García F2, Ramirez Nodal M3, Ruiz Lozano A4, Pérez Díaz CR5, González Valdés A6, Gonzalez Alvarez L7.

Author information: 1 Departamento de Epidemiología Hospitalaria, Hospital Docente Clínico Quirúrgico “Joaquín Albarrán”, La Habana, Cuba. Electronic address: guanche@infomed.sld.cu. 2 Departamento de Epidemiología Hospitalaria, Hospital Docente Clínico Quirúrgico “Joaquín Albarrán”, La Habana, Cuba. Electronic address: fcogutierrez@infomed.sld.cu. 3 Servicio de Medicina Interna, Hospital Docente Clínico Quirúrgico “Joaquín Albarrán”, La Habana, Cuba. Electronic address: manuelramirez@infomed.sld.cu. 4 Centro de Urgencias, Hospital Docente Clínico Quirúrgico “Joaquín Albarrán”, La Habana, Cuba. Electronic address: vd.asistmedica@albarran.sld.cu. 5 Sección Gestión de la Calidad, Hospital Docente Clínico Quirúrgico “Joaquín Albarrán”, La Habana, Cuba. Electronic address: direccion@albarran.sld.cu. 6 Departamento de Epidemiología Hospitalaria, Hospital Docente Clínico Quirúrgico “Joaquín Albarrán”, La Habana, Cuba. Electronic address: anaikagv@infomed.sld.cu. 7 Departamento de Epidemiología Hospitalaria, Hospital Docente Clínico Quirúrgico “Joaquín Albarrán”, La Habana, Cuba. Electronic address: epidemiologia@albarran.sld.cu.

 

Abstract

BACKGROUND:

The clinical characteristics of the most frequent arbovirosis (Dengue, Zika, Chikungunya) are very similar, which is a diagnostic challenge for clinicians.

OBJECTIVE:

To identify the presence of clinical characteristics related to Zika virus infection confirmed by the laboratory in patients during an epidemic of co-infection with Zika and Dengue viruses.

METHOD:

Cross-sectional descriptive study of patients with clinical – epidemiological suspicion of Zika virus infection, who were admitted in the Hospital “Joaquín Albarrán” (La Habana, Cuba), during June 1 to October 31 of 2017. Demographic and symptoms and signs were recorded. By PCR for Zika virus (in blood or urine) the disease was confirmed.

RESULTS:

1541 patients were studied. The most frequent symptoms and signs were rash (93.8%), pruritus (77.9%), arthralgia (60.0%), headache (50.8%), myalgia (46.1%), fever (34.7%), asthenia (31.7%), and conjunctivitis (27.9%). Zika virus infection was confirmed in 279 patients (18.1%). Greater frequency of arthralgia, asthenia, and diarrhea was demonstrated in Zika confirmed patients.

CONCLUSION:

Minor clinical relevance was observed in the symptoms or signs of arboviral disease to support the clinical diagnosis of Zika virus infections by clinician during a Zika-Dengue epidemic. The assessment of the temporality of the onset of Zika and Dengue symptoms of these infections is recommended to assist clinicians in the differential diagnosis.

Copyright © 2019 The Authors. Published by Elsevier Ltd.. All rights reserved.

KEYWORDS: Clinical picture; Cuba; Infection; Non-specific febrile syndrome; Zika

PMID: 31399372 DOI: 10.1016/j.jiph.2019.07.006

Keywords: Arbovirus; Zika virus; Dengue fever.

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Spatial #diffusion of the 2015-2016 #Zika, #dengue and #chikungunya #epidemics in #Rio de Janeiro Municipality, #Brazil (Epidemiol Infect., abstract)

[Source: US National Library of Medicine, full page: (LINK). Abstract, edited.]

Epidemiol Infect. 2019 Jan;147:e237. doi: 10.1017/S0950268819001250.

Spatial diffusion of the 2015-2016 Zika, dengue and chikungunya epidemics in Rio de Janeiro Municipality, Brazil.

Dalvi APR1, Braga JU1.

Author information: 1 Escola Nacional de Saude Publica Sergio Arouca,Fundação Oswaldo Cruz,Rio de Janeiro,Brazil.

 

Abstract

Different countries, especially Brazil, that have faced recurrent dengue epidemics for decades and chikungunya epidemics since 2014, have had to restructure their health services to combat a triple epidemic of arboviruses – Zika, dengue and Chikungunya – transmitted by the same vector, mainly Aedes aegypti, in 2015-2016. Several efforts have been made to better understand these three arboviruses. Spatial analysis plays an important role in the knowledge of disease dynamics. The knowledge of the patterns of spatial diffusion of these three arboviruses during an epidemic can contribute to the planning of surveillance actions and control of these diseases. This study aimed to identify the spatial diffusion processes of these viruses in the context of the triple epidemic in 2015-2016 in Rio de Janeiro, Brazil. Two study designs were used: cross-sectional and ecological. Sequential Kernel maps, nearest-neighbour ratios calculated cumulatively over time, Moran global autocorrelation correlograms, and local autocorrelation changes over time were used to identify spatial diffusion patterns. The results suggested an expansion diffusion pattern for the three arboviruses during 2015-2016 in Rio de Janeiro. These findings can be considered for more effective control measures and for new studies on the dynamics of these three arboviruses.

KEYWORDS: Chikungunya virus; Zika virus; dengue virus; spatio temporal analysis

PMID: 31364556 DOI: 10.1017/S0950268819001250

Keywords: Arbovirus; Zika virus; Dengue fever; Chikungunya fever, Brazil.

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No #evidence of #Zika, #dengue, or #chikungunya virus #infection in field-caught #mosquitoes from the Recife Metropolitan Region, #Brazil, 2015 (Wellcome Open Res., abstract)

[Source: US National Library of Medicine, full page: (LINK). Abstract, edited.]

Wellcome Open Res. 2019 Jun 10;4:93. doi: 10.12688/wellcomeopenres.15295.1. eCollection 2019.

No evidence of Zika, dengue, or chikungunya virus infection in field-caught mosquitoes from the Recife Metropolitan Region, Brazil, 2015.

Ramesh A#1,2, Jeffries CL#3, Castanha P4,5, Oliveira PAS1, Alexander N2, Cameron M3, Braga C1, Walker T3.

Author information: 1 Department of Parasitology, Instituto Aggeu Magalhães(IAM/FIOCRUZ Pernambuco), Recife, Brazil. 2 Department of Infectious Disease Epidemiology, London School of Hygiene & Tropical Medicine, London, WC1E 7HT, UK. 3 Department of Disease Control, London School of Hygiene & Tropical Medicine, London, WC1E 7HT, UK. 4 Department of Virology, Instituto Aggeu Magalhães(IAM/FIOCRUZ Pernambuco), Recife, Brazil. 5 Universidade Estadual de Pernambuco (UPE), Recife, Brazil. #Contributed equally

 

Abstract

Background:

The Recife Metropolitan Region (RMR), north-eastern Brazil, was the epicentre of the 2015 Zika virus (ZIKV) epidemic, which was followed by a 2016 chikungunya virus (CHIKV) epidemic. It historically has amongst the highest incidence of dengue virus (DENV) infections and is the only remaining focus of lymphatic filariasis (LF) in Brazil. In early 2015, a molecular xenomonitoring surveillance project focused on Culex (Cx.) quinquefasciatus commenced to inform LF elimination activities. Aedes (Ae.) aegypti mosquitoes were also collected, concurrent with the first microcephaly cases detected in the RMR. In terms of the 2015 ZIKV epidemic, these are the earliest known field-collected mosquitoes, preserved for potential RNA virus detection, when ZIKV was known to be circulating locally.

Methods:

Adult mosquitoes were collected in two sites (0.4 km 2) of Sítio Novo, Olinda, RMR, from July 22 to August 21, 2015. Mosquitoes were morphologically identified, sorted by physiological status, and pooled (up to 10 mosquitoes per house per day or week). RNA was extracted, reverse transcribed and the cDNA tested by real-time PCR.

Results:

A total of 10,139 adult female Cx. quinquefasciatus and 939 adult female Ae. aegypti were captured. All female Ae. aegypti specimens were included within 156 pools and screened for ZIKV, DENV and CHIKV. In addition, a sub-set of 1,556 Cx. quinquefasciatus adult females in 182 pools were screened for ZIKV. No evidence of infection with any of the three arboviruses was found.

Conclusions:

The absence of arbovirus detection may have been expected given the extremely restricted geographic area and collection of mosquitoes during a very short time period of peak mosquito abundance (July-September), but low arbovirus circulation (November-March).  However, this study demonstrates the potential to retrospectively screen for additional unexpected pathogens in situations of rapid emergence, such as occurred during the outbreak of ZIKV in the RMR.

KEYWORDS: Aedes aegypti; Culex quinquefasciatus; Zika virus; arboviruses; chikungunya virus; dengue virus; disease surveillance; molecular xenomonitoring; neglected tropical diseases; urban areas

PMID: 31363498 PMCID: PMC6644828 DOI: 10.12688/wellcomeopenres.15295.1

Keywords: Arbovirus; Zika virus; Chikungunya fever; Dengue fever; Mosquitoes; Culex quinquefasciatus; Aedes aegypti; Brazil.

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Changing #patterns in the #distribution of the #Mayaro virus #vector #Haemagogus species in #Trinidad, West Indies (Acta Trop., abstract)

[Source: US National Library of Medicine, full page: (LINK). Abstract, edited.]

Acta Trop. 2019 Jul 25:105108. doi: 10.1016/j.actatropica.2019.105108. [Epub ahead of print]

Changing patterns in the distribution of the Mayaro virus vector Haemagogus species in Trinidad, West Indies.

Ali R1, Mohammed A1, Jayaraman J1, Nandram N2, Feng RS1, Lezcano RD2, Seeramsingh R2, Daniel B1, Lovin DD3, Severson DW4, Ramsubhag A5.

Author information: 1 Department of Life Sciences, Faculty of Science & Technology, The University of the West Indies, St. Augustine Campus, Trinidad and Tobago. 2 Insect Vector Control Division, Ministry of Health, Government of Trinidad and Tobago, Trinidad and Tobago. 3 Department of Biological Sciences and Eck institute for Global Health, University of Notre Dame, Notre Dame, Indiana, United States. 4 Department of Life Sciences, Faculty of Science & Technology, The University of the West Indies, St. Augustine Campus, Trinidad and Tobago; Department of Biological Sciences and Eck institute for Global Health, University of Notre Dame, Notre Dame, Indiana, United States. 5 Department of Life Sciences, Faculty of Science & Technology, The University of the West Indies, St. Augustine Campus, Trinidad and Tobago. Electronic address: Adesh.Ramsubhag@sta.uwi.edu.

 

Abstract

The Mayaro virus disease (MAYVD) is an emerging mosquito borne zoonosis that was first reported on the island of Trinidad in 1954. The viral agent for this disease is known to presently be endemic to Central and South America. The enzootic cycle of the Mayaro virus (MAYV) is not fully characterized, though primates are thought to be the main reservoir with Haemagogus species of mosquitoes as the primary vector. This virus has been responsible for several sporadic cases of infections and limited outbreaks, but it is postulated that the MAYVD will become a major epidemic in the future, following in the steps of the recent pandemics caused by Chikungunya and Zika viruses. Mitigating possible major outbreaks of MAYVD in the future would require effective strategies for vector control, for which knowledge on the ecology and distribution of the Haemagogus mosquitoes would be vitally important. In Trinidad, Haemagogus species have only been reported in the northwestern peninsula of the island based on studies up to 1995. However, no recent investigations have been completed to determine the status of this important vector on the island. The aim of this study was to investigate the current spatial distribution of Haemagogus species in the island of Trinidad, West Indies. Adult Haemagogus (Hag.) mosquitoes and larvae were surveyed during a twenty-month period using human bait trapping and ovitraps in major forested areas on the island. Mosquito species were identified using classical taxonomic keys. Haemagogus species were widespread and found in all forest types surveyed. Hag. janthinomys (85.7%) was the most widely distributed and dominant species on the island. Lower levels of Hag. leucocelaneus (7.3%), Hag. equinus (6.4%) and Hag. celeste (0.6%) were also collected. Overall, the proportion of mosquitoes collected in the wet season (June – December) was 3.5 times more than in the dry season (January – May). Mangroves, young secondary forests, semi-evergreen and evergreen forest types had relatively high mean abundance levels of Haemagogus species as compared to deciduous and montane forests. Proximity analysis suggests that population settlements within a 1 km buffer of the forest peripherals may be at risk for any emerging arboviral disease associated with these mosquito vectors. Haemagogus species showed a much wider distribution in Trinidad as compared to previous reports from up to 20 years ago and were prevalent in areas with no known presence of non-human primates. Since the MAYV has been previously implicated in causing infections in vertebrate hosts like rodents, birds and small mammals, the findings of this study suggest that there may be alternative hosts and reservoirs of this virus in the sylvatic cycle in Trinidad, other than primates. This has significant epidemiological implications for mosquito-borne viral infections in the region.

Copyright © 2019. Published by Elsevier B.V.

KEYWORDS: Distribution; Haemagogus; Mayaro Virus; Trinidad; Yellow Fever

PMID: 31351893 DOI: 10.1016/j.actatropica.2019.105108

Keywords: Mayaro virus; Mosquitoes; Trinidad.

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#Autocidal gravid #ovitraps protect humans from #chikungunya virus infection by reducing #Aedes aegypti #mosquito populations (PLoS Negl Trop Dis., abstract)

[Source: PLoS Neglected Tropical Diseases, full page: (LINK). Abstract, edited.]

OPEN ACCESS /  PEER-REVIEWED / RESEARCH ARTICLE

Autocidal gravid ovitraps protect humans from chikungunya virus infection by reducing Aedes aegypti mosquito populations

Tyler M. Sharp , Olga Lorenzi, Brenda Torres-Velásquez, Veronica Acevedo, Janice Pérez-Padilla, Aidsa Rivera, Jorge Muñoz-Jordán, Harold S. Margolis, Stephen H. Waterman, Brad J. Biggerstaff, Gabriela Paz-Bailey, Roberto Barrera

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Published: July 25, 2019 / DOI: https://doi.org/10.1371/journal.pntd.0007538

 

Abstract

Background

Public health responses to outbreaks of dengue, chikungunya, and Zika virus have been stymied by the inability to control the primary vector, Aedes aegypti mosquitos. Consequently, the need for novel approaches to Aedes vector control is urgent. Placement of three autocidal gravid ovitraps (AGO traps) in ~85% of homes in a community was previously shown to sustainably reduce the density of female Ae. aegypti by >80%. Following the introduction of chikungunya virus (CHIKV) to Puerto Rico, we conducted a seroprevalence survey to estimate the prevalence of CHIKV infection in communities with and without AGO traps and evaluate their effect on reducing CHIKV transmission.

Methods and findings

Multivariate models that calculated adjusted prevalence ratios (aPR) showed that among 175 and 152 residents of communities with and without AGO traps, respectively, an estimated 26.1% and 43.8% had been infected with CHIKV (aPR = 0.50, 95% CI: 0.37–0.91). After stratification by time spent in their community, protection from CHIKV infection was strongest among residents who reported spending many or all weekly daytime hours in their community:10.3% seropositive in communities with AGO traps vs. 48.7% in communities without (PR = 0.21, 95% CI: 0.11–0.41). The age-adjusted rate of fever with arthralgia attributable to CHIKV infection was 58% (95% CI: 46–66%). The monthly number of CHIKV-infected mosquitos and symptomatic residents were diminished in communities with AGO traps compared to those without.

Conclusions

These findings indicate that AGO traps are an effective tool that protects humans from infection with a virus transmitted by Ae. aegypti mosquitos. Future studies should evaluate their protective effectiveness in large, urban communities.

 

Author summary

Aedes species mosquitos transmit pathogens of public health importance, including dengue, Zika, and chikungunya viruses. No tools exist to control these mosquitos that sustainably and effectively prevent human infections. Autocidal gravid ovitraps (AGO traps) have been shown to sustainably reduce Aedes populations by >80%. After chikungunya virus was introduced into Puerto Rico, we conducted serosurveys in communities with and without AGO traps. We observed a two-fold lower prevalence of chikungunya virus infection among residents of communities with AGO traps compared to communities without. Among infected residents of communities with traps, a significant proportion likely had been infected while outside their community. These findings indicate that AGO traps are an effective tool that protects humans from infection with pathogens transmitted by Aedes mosquitos.

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Citation: Sharp TM, Lorenzi O, Torres-Velásquez B, Acevedo V, Pérez-Padilla J, Rivera A, et al. (2019) Autocidal gravid ovitraps protect humans from chikungunya virus infection by reducing Aedes aegypti mosquito populations. PLoS Negl Trop Dis 13(7): e0007538. https://doi.org/10.1371/journal.pntd.0007538

Editor: Paulo Pimenta, Fundaçao Oswaldo Cruz, BRAZIL

Received: March 15, 2019; Accepted: June 10, 2019; Published: July 25, 2019

This is an open access article, free of all copyright, and may be freely reproduced, distributed, transmitted, modified, built upon, or otherwise used by anyone for any lawful purpose. The work is made available under the Creative Commons CC0 public domain dedication.

Data Availability: All relevant data will be submitted within Supporting Information files.

Funding: The authors received no specific funding for this work.

Competing interests: The authors have declared that no competing interests exist. Autocidal gravid ovitraps (AGO traps) used in this study were developed and constructed by CDC personnel (RB). Rights for the AGO trap patent (US 9.237,741 B2) were transferred to the US Government (Executive Order 10096). Eventual royalties derived from trap sales by licensed companies follow 15 U.S.C. 3710c.

Keywords: Arbovirus; Chikungunya fever; Aedes aegypti; Mosquitoes; Ovitraps.

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