Short report: Serological evidence of West Nile virus activity in El Salvador

Lilian Cruz, Victor M. Cardenas, Mauricio Abarca, Tito Rodriguez, Roberto Flores Reyna, Mario V. Serpas, Robert E. Fontaine, David W C Beasley, Amelia P A Travassos Da Rosa, Scott C. Weaver, Robert B. Tesh, Ann M. Powers, Gloria Suarez-Rangel