Ross River virus antibody prevalence in the Fiji Islands, 2013-2015

A unique outbreak of Ross River virus (RRV) infection was reported in Fiji in 1979. In 2013, 29 RRV seroprevalence among residents was 46.5%. Of those born after 1982, 37.4% had anti-RRV 30 antibodies. Between 2013-2015, 10.9% of residents had seroconverted to RRV suggesting 31 ongoing endemic circulation of RRV in Fiji

Ross River virus antibody prevalence in the Fiji Islands, 2013-2015

A unique outbreak of Ross River virus (RRV) infection was reported in Fiji in 1979. In 2013, 29 RRV seroprevalence among residents was 46.5%. Of those born after 1982, 37.4% had anti-RRV 30 antibodies. Between 2013-2015, 10.9% of residents had seroconverted to RRV suggesting 31 ongoing endemic circulation of RRV in Fiji

Expressed repetitive elements are broadly applicable reference targets for normalization of reverse transcription-qPCR data in mice

Reverse transcription quantitative PCR (RT-qPCR) is the gold standard method for gene expression analysis on mRNA level. To remove experimental variation, expression levels of the gene of interest are typically normalized to the expression level of stably expressed endogenous reference genes. Identifying suitable reference genes and determining the optimal number of reference genes should precede each quantification study. Popular reference genes are not necessarily stably expressed in the examined conditions, possibly leading to inaccurate results. Stably and universally expressed repetitive elements (ERE) have previously been shown to be an excellent alternative for normalization using classic reference genes in human and zebrafish samples. Here, we confirm that in mouse tissues, EREs are broadly applicable reference targets for RT-qPCR normalization, provided that the RNA samples undergo a thorough DNase treatment. We identified Orr1a0, Rltr2aiap, and Rltr13a3 as the most stably expressed mouse EREs across six different experimental conditions. Therefore, we propose this set of ERE reference targets as good candidates for normalization of RT-qPCR data in a plethora of conditions. The identification of widely applicable stable mouse RT-qPCR reference targets for normalization has great potential to facilitate future murine gene expression studies and improve the validity of RT-qPCR data

Using paired serology and surveillance data to quantify dengue transmission and control during a large outbreak in Fiji.

Dengue is a major health burden, but it can be challenging to examine transmission and evaluate control measures because outbreaks depend on multiple factors, including human population structure, prior immunity and climate. We combined population-representative paired sera collected before and after the 2013/14 dengue-3 outbreak in Fiji with surveillance data to determine how such factors influence transmission and control in island settings. Our results suggested the 10-19 year-old age group had the highest risk of infection, but we did not find strong evidence that other demographic or environmental risk factors were linked to seroconversion. A mathematical model jointly fitted to surveillance and serological data suggested that herd immunity and seasonally varying transmission could not explain observed dynamics. However, the model showed evidence of an additional reduction in transmission coinciding with a vector clean-up campaign, which may have contributed to the decline in cases in the later stages of the outbreak

Sustained Low-Level Transmission of Zika and Chikungunya Viruses after Emergence in the Fiji Islands.

Zika and chikungunya viruses were first detected in Fiji in 2015. Examining surveillance and phylogenetic and serologic data, we found evidence of low-level transmission of Zika and chikungunya viruses during 2013-2017, in contrast to the major outbreaks caused by closely related virus strains in other Pacific Island countries

Molecular and clinical investigation of Zika virus outbreak in New Caledonia

&lt;p&gt;Introduction: Zika virus (ZIKV) is an emerging mosquito-borne pathogen transmitted to humans byinfected Aedes mosquitoes. In 2016, WHO declared ZIKV as a Public Health Emergency ofInternational Concern regarding clusters of microcephaly cases and neurological disorders probablylinked to ZIKV infection. Before that, ZIKV emerged in the Pacific for the first time in 2007. In 2013French Polynesia (FP) experienced a large Zika outbreak. ZIKV then spread throughout the Pacificduring the following two years and reached Brazil where a major outbreak is occurring. In NewCaledonia (NC), a ZIKV outbreak occurred in 2014 and 2015 with more than 1500 cases of ZIKVconfirmed by RT-PCR.Method: However, the diagnostic of ZIKV cases was challenging due to low sensitivity of RT-PCRtechnics on serum samples. We thus explored the detection of ZIKV in non-invasive samples. Wealso investigated the molecular evolution of ZIKV in NC compared to other regions in the world.Results/Conclusion: Here, we highlighted a better sensitivity of ZIKV detection by RT-PCR in urinesamples with longer and higher presence of ZIKV RNA compared to serum. Phylogenetic analysisconfirmed the epidemiological link between FP and NC ZIKV strains. Finally results of clinicalinvestigations regarding probable neurological disorders linked to ZIKV infection will be presented.&lt;/p&gt;</p

Using paired serology and surveillance data to quantify dengue transmission and control during a large outbreak in Fiji

Dengue is a major health burden, but it can be challenging to examine transmission and evaluate control measures because outbreaks depend on multiple factors, including human population structure, prior immunity and climate. We combined population-representative paired sera collected before and after the 2013/14 dengue-3 outbreak in Fiji with surveillance data to determine how such factors influence transmission and control in island settings. Our results suggested the 10-19 year-old age group had the highest risk of infection, but we did not find strong evidence that other demographic or environmental risk factors were linked to seroconversion. A mathematical model jointly fitted to surveillance and serological data suggested that herd immunity and seasonally varying transmission could not explain observed dynamics. However, the model showed evidence of an additional reduction in transmission coinciding with a vector clean-up campaign, which may have contributed to the decline in cases in the later stages of the outbreak

Using paired serology and surveillance data to quantify dengue transmission and control during a large outbreak in Fiji

Dengue is a major health burden, but it can be challenging to examine transmission and evaluate control measures because outbreaks depend on multiple factors, including human population structure, prior immunity and climate. We combined population-representative paired sera collected before and after the 2013/14 dengue-3 outbreak in Fiji with surveillance data to determine how such factors influence transmission and control in island settings. Our results suggested the 10–19 year-old age group had the highest risk of infection, but we did not find strong evidence that other demographic or environmental risk factors were linked to seroconversion. A mathematical model jointly fitted to surveillance and serological data suggested that herd immunity and seasonally varying transmission could not explain observed dynamics. However, the model showed evidence of an additional reduction in transmission coinciding with a vector clean-up campaign, which may have contributed to the decline in cases in the later stages of the outbreak.Medical Research Council (MR/K021524/1) Adam J Kucharski Wellcome Trust (206250/Z/17/Z) Adam J Kucharski Royal Society (206250/Z/17/Z) Adam J Kucharski Embassy of France in the Republic of Fiji, Kiribati, Nauru, Tonga and Tuvalu Mike Kama French Ministry for Europe and Foreign Affairs (Pacific Funds N°12115-02/09/15) Mike Kama Van-Mai Cao-Lormeau French Ministry for Europe and Foreign Affairs (Pacific Funds N°03016-20/05/16) Mike Kama Van-Mai Cao-Lormeau Medical Research Council (MR/J003999/1) Conall H Watson Commissariat Général à l'Investissement (ANR-10-LABX-62-IBEID) Jessica Vanhomwegen Jean-Claude Manuguerra National Health and Medical Research Council (1109035) Colleen L Lau French Ministry for Europe and Foreign Affairs (Pacific Funds N°06314-09/04/14) Van-Mai Cao-Lormeau Janssen Research and Development (Janssen Sciences Ireland UC) Stéphane Hué Martin L Hibber

Sustained low-level transmission of zika and chikungunya viruses after emergence in the Fiji Islands

Zika and chikungunya viruses were first detected in Fiji in 2015. Examining surveillance and phylogenetic and serologic data, we found evidence of low-level transmission of Zika and chikungunya viruses during 2013-2017, in contrast to the major outbreaks caused by closely related virus strains in other Pacific Island countries