Chikungunya virus infections among travellers returning to Spain, 2008 to 2014.

Since the first documented autochthonous transmission of chikungunya virus in the Caribbean island of Saint Martin in 2013, the infection has been reported within the Caribbean region as well as North, Central and South America. The risk of autochthonous transmission of chikungunya virus becoming established in Spain may be elevated due to the large numbers of travellers returning to Spain from countries affected by the 2013 epidemic in the Caribbean and South America, as well as the existence of the Aedes albopictus vector in certain parts of Spain. We retrospectively analysed the laboratory diagnostic database of the National Centre for Microbiology, Institute of Health Carlos III (CNM-ISCIII) from 2008 to 2014. During the study period, 264 confirmed cases, of 1,371 suspected cases, were diagnosed at the CNM-ISCIII. In 2014 alone, there were 234 confirmed cases. The highest number of confirmed cases were reported from the Dominican Republic (n = 136), Venezuela (n = 30) and Haiti (n = 11). Six cases were viraemic in areas of Spain where the vector is present. This report highlights the need for integrated active case and vector surveillance in Spain and other parts of Europe where chikungunya virus may be introduced by returning travellers.

Imported cases of Chikungunya in Barcelona in relation to the current American outbreak.

BACKGROUND: The Chikungunya virus (CKIKV) is currently present in America. Travel between America and Europe is particularly intense and one of the main vectors of CHIKV, Aedes albopictus, is well established in the Mediterranean basin. We describe a series of imported cases that could originate a European outbreak. METHODS: We retrospectively studied cases of CHIKV originating in America and diagnosed in the last year in three Tropical Medicine Units of Barcelona of the International Health Program of the Catalan Health Institute (PROSICS). Clinical, microbiological and epidemiological data were analyzed. RESULTS: Forty-two CHIKV cases who had returned from 11 American countries were included. Fever was the most common symptom at onset (96.1%). Three months after symptom onset 50% continued with arthralgias, 35.3% fatigue and 11.8% arthritis. Three patients were viremic at the time of diagnosis by RT-PCR, and the remaining were diagnosed by serology (CHIKV IgM or IgG). Five (11.9%) patients had positive IgM for both dengue virus and CHIKV. CONCLUSIONS: The origin of the cases was diverse, the most frequent being initially the Dominican Republic, followed later by Venezuela and Colombia. Symptoms were not severe but persisted, accompanied by unremitting positive IgM. Diagnosis was mainly based on serology and RT-PCR, with the performance of the rapid immunochromatographic test being low. Phylogenetic studies showed that two viremic cases were caused by a strain of Asian lineage with a lower adaptability to Aedes albopictus. Co-infection with the dengue virus was common, but the clinical course was not affected by coinfection. Non-steroidal anti-inflammatory drugs were administered to 71.4% and steroids to 21.4%. The number of imported cases of CHIKV in Spain is rising due to introduction of this virus in America, and this could lead to an autochthonous outbreak if Public Health measures are not taken.