Cryptosporidium spp.: Serum Antibodies and Coproantigens in Brown Rats (Rattus norvegicus) from Grenada, West Indies

The aim of the study was to determine the serum antibodies and coproantigens for Cryptosporidium spp. in brown rats from Grenada. Intestinal contents from 99 and serum from 169 brown rats (Rattus norvegicus) during May to July 2017 were examined for coproantigens and antibodies for Cryptosporidium spp. respectively. Giardia/Cryptosporidium Quick Chek (Tech Lab Inc, USA) was used to detect Cryptosporidium coproantigens in intestinal contents. Prevalence of antigens was 2.02%, signifying active infection. Serum anti-Cryptosporidium antibodies against Cryptosporidium were tested using commercial “qualitative rat Cryptosporidium antibody (Anti-CRY) ELISA kit (My BioSource, Santiago, CA, USA). Serum antibodies were present in 29.5% of the rats indicating a heavy exposure of Cryptosporidium in brown rats from Grenada. The prevalence rate of antibodies in younger rats (up to100g weight) 42.1%, was statistically significant compared to adults (> 100 g) 28.0%. Infected rats in nearby human dwellings may prove a potential Cryptosporidium source of infection to man and animals. This is the first report of Cryptosporidium infection in brown rats in Grenada, West Indies.