Evaluation of malaria surveillance using retrospective, laboratory-based active case detection in Trinidad, West Indies (1988-1998)

ABSTRACT

OBJECTIVE: To determine the completeness of reporting malaria cases by the Insect Vector Control Division (IVCD), hospitals and commercial laboratories (HCL) in Trinidad during 1989-1998. METHOD: Cases of malaria identified by HCLs were compared with those identified through the IVCD laboratory-based active case detection surveillance system. Since IVCD is the reference laboratory for malaria diagnosis, the data were analyzed for north and south Trinidad. The completeness of reporting malaria cases was calculated using the Lincoln-Peterson capture-recapture technique. RESULTS: Of the 118 cases of malaria identified through the IVCD and HCLs in Trinidad, 23 (67 percent) came from north Trinidad and 24 (100 percent) from south Trinidad. IVCD identified 117 cases (>99 percent). Completeness of reporting, calculating using the Lincoln-Peterson capture-recapture technique was 99.2 percent for IVCD laboratory-based case detection programme. CONCLUSION: The high percentage of cases identified by IVCD suggests that the Malaria Surveillance programme provides trends that accurately reflect the epidemiology of malaria in Trinidad and Tobago. Cases identified may be improved by promoting confirmatory testing for all laboratories, clinicians' updates and incorporating laboratory-based reporting into the wider surveillance system.(AU)