Establishment of laboratory testing capability for chikungunya virus in Grenada, West Indies

ABSTRACT

OBJECTIVE: Rapid diagnosis of Chikungunya (CHIKV) is important early in an epidemic. The study objective was to describe the process of implementing CHIKV testing capability in Grenada and to confirm the arrival of CHIKV on the main island of Grenada. DESIGN AND METHODS: In April, 2014 a collaborative study between the U.S. Naval Infectious Diseases Diagnostic Laboratory (NIDDL) and the clinical microbiology laboratory of St. George’s University (SGU) was started. SGU acquired essential instrumentation and patient samples, and NIDDL provided supplies and reagents, plus technical training experts. RESULTS: Personnel, supplies and equipment arrived in Grenada in August 2014. Set up of instruments and test validation were completed quickly. Initial CHIKV PCR and IgM tests found 3 PCR positive samples. The IgM assay found several presumptive positives that were unable to be confirmed due to ELISA instrument malfunction. PCR data indicated that CHIKV had arrived on the main island of Grenada no later than August, 2014. Based on arbovirus test demand, symptomatic patients began to increase in August, peaked in September, and tailed off during November. CONCLUSION: Both CHIKV tests were implemented and produced the first on-island reference test confirmation of CHIKV patients in Grenada. The most difficult part of this effort was training technologists in time to help with testing. Laboratory testing for CHIKV infection can be a challenge in developing states at a distance from support services. Collaborative links with established labs remains essential.