Multiple arboviral infections during a DENV-2 outbreak in Solomon Islands

Abstract Background Solomon Islands, a country made up of tropical islands, has suffered cyclic dengue fever (DF) outbreaks in the past three decades. An outbreak of dengue-like illness (DLI) that occurred in April 2016 prompted this study, which aimed to determine the population’s immunity status a...

Full description

Bibliographic Details
Main Authors: Andrew Waleluma Darcy, Seiji Kanda, Tenneth Dalipanda, Cynthia Joshua, Takaki Shimono, Pheophet Lamaningao, Nobuyuki Mishima, Toshimasa Nishiyama
Format: Article
Language:English
Published: BMC 2020-05-01
Series:Tropical Medicine and Health
Subjects:
Online Access:http://link.springer.com/article/10.1186/s41182-020-00217-8
_version_ 1818910888606826496
author Andrew Waleluma Darcy
Seiji Kanda
Tenneth Dalipanda
Cynthia Joshua
Takaki Shimono
Pheophet Lamaningao
Nobuyuki Mishima
Toshimasa Nishiyama
author_facet Andrew Waleluma Darcy
Seiji Kanda
Tenneth Dalipanda
Cynthia Joshua
Takaki Shimono
Pheophet Lamaningao
Nobuyuki Mishima
Toshimasa Nishiyama
author_sort Andrew Waleluma Darcy
collection DOAJ
description Abstract Background Solomon Islands, a country made up of tropical islands, has suffered cyclic dengue fever (DF) outbreaks in the past three decades. An outbreak of dengue-like illness (DLI) that occurred in April 2016 prompted this study, which aimed to determine the population’s immunity status and identify the arboviruses circulating in the country. Methods A household survey, involving 188 participants in two urban areas (Honiara and Gizo), and a parallel hospital-based clinical survey were conducted in April 2016. The latter was repeated in December after a surge in DLI cases. Arbovirus IgG ELISA were performed on the household blood samples to determine the prevalence of arboviruses in the community, while qPCR testing of the clinical samples was used to identify the circulating arboviruses. Dengue virus (DENV)-positive samples were further characterized by amplifying and sequencing the envelope gene. Results The overall prevalence rates of DENV, Zika virus, and chikungunya virus were 83.4%, 7.6%, and 0.9%, respectively. The qPCR positivity rates of the clinical samples collected in April 2016 were as follows: DENV 39.6%, Zika virus 16.7%, and chikungunya virus 6.3%, which increased to 74%, 48%, and 20% respectively in December 2016. The displacement of the circulating serotype-3, genotype-1, with DENV serotype 2, genotype cosmopolitan was responsible for the outbreak in 2016. Conclusions A DENV outbreak in Solomon Islands was caused by the introduction of a single serotype. The high prevalence of DENV provided transient cross-protection, which prevented the introduction of a new serotype from the hyperendemic region for at least 3 years. The severe outcomes seen in the recent outbreak probably resulted from changes in the causative viruses and the effects of population immunity and changes in the outbreak pattern. Solomon Islands needs to step up surveillance to include molecular tools, increase regional communication, and perform timely interventions.
first_indexed 2024-12-19T22:49:58Z
format Article
id doaj.art-f4b7aa5c39e142a4a9c45b70e75af0a8
institution Directory Open Access Journal
issn 1349-4147
language English
last_indexed 2024-12-19T22:49:58Z
publishDate 2020-05-01
publisher BMC
record_format Article
series Tropical Medicine and Health
spelling doaj.art-f4b7aa5c39e142a4a9c45b70e75af0a82022-12-21T20:02:52ZengBMCTropical Medicine and Health1349-41472020-05-0148111110.1186/s41182-020-00217-8Multiple arboviral infections during a DENV-2 outbreak in Solomon IslandsAndrew Waleluma Darcy0Seiji Kanda1Tenneth Dalipanda2Cynthia Joshua3Takaki Shimono4Pheophet Lamaningao5Nobuyuki Mishima6Toshimasa Nishiyama7Department of Hygiene and Public Health, Kansai Medical UniversityDepartment of Hygiene and Public Health, Kansai Medical UniversityMinistry of Health & Medical ServicesMinistry of Health & Medical ServicesDepartment of Hygiene and Public Health, Kansai Medical UniversityDepartment of Hygiene and Public Health, Kansai Medical UniversityDepartment of Hygiene and Public Health, Kansai Medical UniversityDepartment of Hygiene and Public Health, Kansai Medical UniversityAbstract Background Solomon Islands, a country made up of tropical islands, has suffered cyclic dengue fever (DF) outbreaks in the past three decades. An outbreak of dengue-like illness (DLI) that occurred in April 2016 prompted this study, which aimed to determine the population’s immunity status and identify the arboviruses circulating in the country. Methods A household survey, involving 188 participants in two urban areas (Honiara and Gizo), and a parallel hospital-based clinical survey were conducted in April 2016. The latter was repeated in December after a surge in DLI cases. Arbovirus IgG ELISA were performed on the household blood samples to determine the prevalence of arboviruses in the community, while qPCR testing of the clinical samples was used to identify the circulating arboviruses. Dengue virus (DENV)-positive samples were further characterized by amplifying and sequencing the envelope gene. Results The overall prevalence rates of DENV, Zika virus, and chikungunya virus were 83.4%, 7.6%, and 0.9%, respectively. The qPCR positivity rates of the clinical samples collected in April 2016 were as follows: DENV 39.6%, Zika virus 16.7%, and chikungunya virus 6.3%, which increased to 74%, 48%, and 20% respectively in December 2016. The displacement of the circulating serotype-3, genotype-1, with DENV serotype 2, genotype cosmopolitan was responsible for the outbreak in 2016. Conclusions A DENV outbreak in Solomon Islands was caused by the introduction of a single serotype. The high prevalence of DENV provided transient cross-protection, which prevented the introduction of a new serotype from the hyperendemic region for at least 3 years. The severe outcomes seen in the recent outbreak probably resulted from changes in the causative viruses and the effects of population immunity and changes in the outbreak pattern. Solomon Islands needs to step up surveillance to include molecular tools, increase regional communication, and perform timely interventions.http://link.springer.com/article/10.1186/s41182-020-00217-8Dengue feverArbovirusSeroprevalenceMolecularImmunity
spellingShingle Andrew Waleluma Darcy
Seiji Kanda
Tenneth Dalipanda
Cynthia Joshua
Takaki Shimono
Pheophet Lamaningao
Nobuyuki Mishima
Toshimasa Nishiyama
Multiple arboviral infections during a DENV-2 outbreak in Solomon Islands
Tropical Medicine and Health
Dengue fever
Arbovirus
Seroprevalence
Molecular
Immunity
title Multiple arboviral infections during a DENV-2 outbreak in Solomon Islands
title_full Multiple arboviral infections during a DENV-2 outbreak in Solomon Islands
title_fullStr Multiple arboviral infections during a DENV-2 outbreak in Solomon Islands
title_full_unstemmed Multiple arboviral infections during a DENV-2 outbreak in Solomon Islands
title_short Multiple arboviral infections during a DENV-2 outbreak in Solomon Islands
title_sort multiple arboviral infections during a denv 2 outbreak in solomon islands
topic Dengue fever
Arbovirus
Seroprevalence
Molecular
Immunity
url http://link.springer.com/article/10.1186/s41182-020-00217-8
work_keys_str_mv AT andrewwalelumadarcy multiplearboviralinfectionsduringadenv2outbreakinsolomonislands
AT seijikanda multiplearboviralinfectionsduringadenv2outbreakinsolomonislands
AT tennethdalipanda multiplearboviralinfectionsduringadenv2outbreakinsolomonislands
AT cynthiajoshua multiplearboviralinfectionsduringadenv2outbreakinsolomonislands
AT takakishimono multiplearboviralinfectionsduringadenv2outbreakinsolomonislands
AT pheophetlamaningao multiplearboviralinfectionsduringadenv2outbreakinsolomonislands
AT nobuyukimishima multiplearboviralinfectionsduringadenv2outbreakinsolomonislands
AT toshimasanishiyama multiplearboviralinfectionsduringadenv2outbreakinsolomonislands