Because of the high number of mosquito species and especially the abundance of Aedes albopictus mosquitoes , the Seychelles remain under the threat of outbreaks, particularly arboviruses . However, only limited data are available on the types and molecular characteristics of arboviruses circulating in the region. In this report we investigated an outbreak of dengue virus (DENV) infection in six Israeli travellers returning from the Seychelles, a popular tourist destination located in the Indian ocean east of the East African coast with a population of roughly 90,000 inhabitants.
Nine Israeli citizens who had travelled to the Seychelles islands reported a febrile illness which started 1–2 days after returning to Israel. They were part of a group of 32 travellers visiting a different island every day between 13 and 22 April 2017. The islands visited, in consecutive order, were: Mahe, Curieuse, Aride, Praslin, La Digue and Moyenne.
In six of the febrile travellers, dengue fever was confirmed, in four of them by both quantitative (q) RT-PCR  or PCR  and DENV IgM and IgG antibody capture ELISA (Panbio, Brisbane, Australia), in one only by qRT-PCR, and in one only by positive dengue virus NS1 antigen (Panbio, Brisbane, Australia) and IgM and IgG serology (Table). Since DENV RNA in serum can only be detected for a short time after symptom onset [5-8], DENV RNA in urine and whole blood was tested for samples obtained more than 10 days post symptom onset (Table). qRT-PCR of DENV-1–4  or PCR  demonstrated that all five PCR-positve cases had DENV type 2. The remaining three febrile patients did not present to our clinics and therefore were not tested for dengue.