Dengue activity in Puerto Rico

ABSTRACT

The laboratory-based dengue surveillance program in Puerto Rico aims to provide early and precise information to public health officials on four aspects of increased dengue activity time, location, virus stereotype, and disease severity. The Dengue Branch, San Juan Laboratories (SJL) of the National Center for Infectious Diseases, Centers for Disease Control, receives blood specimens from government clinics, public and private hospitals, and physicians' offices throughout Puerto Rico. These specimens are sent directly or collected locally and transported to SJL by personnel of the Community Hygiene Division (HAFI, for its initials in Spanish) of the Puerto Rico Health Department (PRHD). All serum specimens are tested for anti-dengue IgM to a mixture of four dengue virus antigens, by IgM antibody capture enzyme-linked immunosorbent assay (MAC-ELISA). All specimens that test positive by MAC-ELISA are further evaluated with an IgG-ELISA to determine whether the infection is primary or secondary. Up to 125 early acute-phase samples per week are processed in C636 mosquito cell cultures for attempted virus isolation. In addition, sera from all patients with haemorrhagic manifestations and all patients from outside Puerto Rico and the U.S. Virgin Islands, if collected fewer than 6 days after onset of illness, are injected into Toxorhynchites mosquitoes. Dengue virus-infected cell cultures or tissues from inoculated mosquitoes (AU)