Incidence of Zika virus infection in a prospective cohort of Belgian travellers to the Americas in 2016

Abstract

were recruited prospectively to study the incidence and characteristics of ZIKV. Demographic data and sera were collected at baseline. Participants were trained to collect capillary blood on filter paper (BFP). When ill during travel, the participants completed a questionnaire and they sampled BFP for post-hoc analysis. All symptomatic participants were screened for ZIKV using ZIKV-specific RT-PCR on serum or urine, or BFP, and antibody detection assays (ELISA). Follow-up sera of asymptomatic travellers, obtained at least 20 days post travel, were tested by ZIKV ELISA only. All positive ELISA results were subject to confirmation by virus neutralization testing (VNT). Results: Forty-nine participants completed follow-up: 38 women and 11 men, with a median age of 32 years (range 19-64 years). Travel destinations were countries in South America (n = 20), Central America (n = 24), and the Caribbean (n = 5). The total travel duration was 67.8 person-months. Illness was reported by 24 participants (49.0%). ZIKV infection was confirmed in nine cases, by RT-PCR (n = 5) and by VNT (n = 4). Only one of nine ZIKV cases (11.1%) was asymptomatic. The ZIKV incidence rate was 17.0% (95% confidence interval 7.8-32.2%) per month of travel. Conclusions: The ZIKV incidence rate in adult travellers from non-endemic countries to the epidemic territories during the 2016 outbreak was high. Asymptomatic ZIKV infection was rare in this population.

ZikaPLAN: addressing the knowledge gaps and working towards a research preparedness network in the Americas

“…Furthermore, expanding from our previous collaboration with the European network on sentinel surveillance in returning travellers (TropNet) through DengueTools [71], we prospectively enrolled travellers with laboratory-confirmed ZIKV infections. We found the incidence rate of ZIKV infection in European travellers to affected territories to be as high as 17% (95% confidence interval, 8 to 32) per month of travel during the height of the outbreak [72]. In this study, all symptomatic travellers had been infected within 3 weeks of arrival in areas that reported ZIKV circulation.…”

Non-Invasive versus Invasive Samples for Zika Virus Surveillance: A Comparative Study in New Caledonia and French Guiana in 2015–2016

“…The massive concentration of humans and animals in one place, combined with the high exchange of persons, animals, and products worldwide, drastically increases the risk of exposure to new, emerging, and exotic infections with an enlarged potential for spread [ 1 , 2 , 3 , 4 , 5 , 6 , 7 ]. Among the emerging pathogens, Zika virus (ZIKV), a single-strand RNA flavivirus, has been responsible for several outbreaks, such as that in 2007 in the Federated States of Micronesia; in 2013–2014 in New Caledonia and other Pacific islands; and in 2014–2016 in Central and Latin America and the United States.…”

“…Among the emerging pathogens, Zika virus (ZIKV), a single-strand RNA flavivirus, has been responsible for several outbreaks, such as that in 2007 in the Federated States of Micronesia; in 2013–2014 in New Caledonia and other Pacific islands; and in 2014–2016 in Central and Latin America and the United States. Moreover, several cases of travelers returning from areas with endemic/epidemic Zika fever have been reported [ 1 , 2 , 3 , 4 , 5 , 6 , 7 ]. This arbovirus is mainly transmitted to human by Aedes aegypti and Aedes albopictus mosquito bites, of which geographical expansion is accentuated by urbanization, global warming, and travel [ 1 , 6 , 8 ].…”