Arbovirus surveillance near the Mexico-U.S. border: co-circulation of dengue virus serotypes 1, 2 and 3, West Nile virus and chikungunya virus in Tamaulipas, northern Mexico

Abstract

A clinical, serological, and molecular investigation was performed to determine the presence of dengue virus (DENV) and other mosquitotransmitted viruses among residents of the city of Reynosa, Tamaulipas on the Mexico-U.S. border in 2014 to 2016. The sample population consisted of 2355 patients with suspected dengue, in addition to 346 asymptomatic individuals recruited during a household-based epidemiological investigation designed to identify flavivirus seroconversions. Sera were collected from patients with suspected dengue in the acute phase of illness and from asymptomatic individuals at enrollment and every 5 to 7 months for 19 months. Sera from suspected dengue patients were tested for DENV antigen by enzyme-linked immunosorbent assay (ELISA) and select antigen-positive sera were further tested using a serotype-specific, quantitative reserve transcription-polymerase chain reaction. Sera from a subset of patients was also tested for chikungunya virus (CHIKV) RNA. A total of 418 (17.7%) patients with suspected dengue had laboratoryconfirmed DENV infections, including 82 patients positive for DENV RNA. Three serotypes were detected (DENV-1, DENV-2, and DENV-3). CHIKV RNA was detected in 13 of 34 (38.2%) patients, including five who also contained DENV antigen. Sera from the household cohort were tested for flavivirus-reactive antibodies by immunoglobulin (Ig) M and IgG ELISAs using DENV antigen. A total of 217 (62.7%) household participants had flavivirus-reactive antibodies at enrollment and nine flavivirus-naïve individuals seroconverted. Sera from a subset of participants, including all those who seroconverted, were further tested by plaque reduction neutralization test, resulting in the detection of antibodies to DENV-1 and West Nile virus. In summary, we provide evidence for the co-circulation of five medically important arboviruses in Reynosa, Tamaulipas on the Mexico-U.S. border.