To the Editor: Recently West Nile virus (WNV) infection has been reported in three alligators (Alligator sp.) from central Florida (1) and one captive crocodile monitor (Varanus salvadori) with neurologic signs from the District of Columbia and Maryland area (2). These first reports of the virus in American reptiles highlight the possible role of this group of vertebrates in the WNV life cycle. To our knowledge, WNV in a reptile was reported only once before in a serosurvey conducted in Israel from 1965 to 1966, in which 22 reptiles and 96 amphibians were tested for hemagglutination-inhibiting antibodies against several viruses, including WNV; one turtle (Clemmys caspica) was seropositive (3). Experimental infection of the lake frog (Rana ridibunda) with a Russian strain of WNV resulted in high levels of viremia (4). At present, the role of reptiles and amphibians in the life cycle and epidemiology of WNV is not known. We report, for the first time, WNV infection in crocodiles (Crocodylus niloticus). To assess the potential role of crocodiles in the life cycle of WNV in Israel, serum specimens were collected from 20 healthy crocodiles on a commercial farm in the Negev Desert, in southern Israel (31 14′ N, 34 19′ E). The crocodiles came from two separate breeding farms (32 03′ N, 35 26′ E and 30 18′ N, 35 07′ E) in the Syrian-African Rift Valley, which is on the main route of bird migration from Africa to Europe. Five males and 15 females, 1–2.5 years of age, were examined. Blood was withdrawn from the crocodiles’ ventral caudal vein, separated by centrifugation, and kept at–20 C until analyzed. Neutralizing antibody titers were determined against WN-goose-98 (5) and attempts to isolate the virus were performed by using Vero cell culture (6) and by using direct reverse transcription–polymerase chain reaction (RTPCR) on the serum specimens. To eliminate the possibilities of nonspecific reaction, all serum samples were concurrently tested for the only other flavivirus known to be present in Israel; Israeli turkey meningoencephalitis virus (ITV)(7). Because ITV does not produce cytopathic effects (CPE) in Vero cells, virus neutralization was conducted on BHK cells for both WNV and ITV by using WN-goose-98 and ITV (vaccine strain). In this case, the virus stocks (10-4.2 50% tissue culture infective dose) were diluted 1: 400, and virus neutralization titers were checked 3 days later.