Serosurvey for Evidence of Dengue and West Nile Virus Human Infections in El Paso, Texas
Dengue viruses (DENV), including the 4 serotypes are the cause of dengue fever and dengue hemorrhagic fever. The viruses are transmitted by Aedes aegypti mosquitoes in urban communities in tropical, sub-tropical, and temperate regions and are the cause of the highest rate of infection and death of all known Flaviviruses. DENV are endemic in United States (US) -Mexico (MX) border communities in the Rio Grande Valley and suspected of being endemic in Ciudad Juarez, a sister city to El Paso, TX. To determine if DENV were endemic in the El Paso community, cord-blood samples from mothers were tested for antibody by an enzyme-linked immunosorbent assay (ELISA), plaque reduction neutralization test (PRNT), and microsphere-immunoassay (MIA). DENV antibody positive samples were further tested for West Nile Virus (WNV) antibody for the possibility of cross-reactivity, considering that WNV is enzootic in El Paso, TX. Of the 1,472 mothers who participated in the study, 0.74% (11/1,472) were positive for DENV antibodies as evidence of a past DENV infection, 3.30% (48/1,472) were positive for WNV antibody, and 0.20% (3/1,472) of the mothers were positive for antibodies to both viruses. The results for 0.20% (3/1472) of the mothers were positive for antibody to only WNV envelope indicating undetermined flavivirus exposure. Another 0.8% (13/1472) of the plasma samples were reactive by ELISA but were negative by the PRNT and MIA. An additional 28 ELISA non-reactive samples were also non-reactive by the MIA and PRNT, thus confirming the accuracy of the ELISA results. Overall, the results for the UTEP-PRNT and the NY-MIA were in concordance for 91% (91/100) of the samples tested for DENV and WNV antibodies. Although 6 of the 11 DENV antibody positive mothers did not have a history of travel to a DENV endemic country, the findings of this survey provided further evidence of local transmission of WNV but did not support a stable state of autochthonous transmission of DENV in the El Paso community.
Suarez, Veronica, "Serosurvey for Evidence of Dengue and West Nile Virus Human Infections in El Paso, Texas" (2019). ETD Collection for University of Texas, El Paso. AAI22621032.