Antigenic distribution of west nile virus in various organs of wildly infected american crows (corvus brachyrhynchos).

Objective: Since its discovery in the western hemisphere in 1999, West Nile virus (WNv) has caused extensive bird mortality across North America, especially in American crows (Corvus brachyrhynchos) which are highly susceptible to WNv. In this study, antigenic distribution of WNv among different organs of American crows was studied, using the immunohistochemistry technique (IHC).

Materials And Methods: Dead crows reported by residents were collected, transported on ice, and were necropsied for heart, lung, brain, intestine, kidney, liver, spleen, pancreas, and gonad tissues.

Comparison of immunohistochemistry and polymerase chain reaction for detection of West Nile virus in naturally infected dead birds.

Introduction: Credible vector-borne disease surveillance programs, especially in developing countries with limited resources, must include diagnostic tests that are efficient, inexpensive and simple and safe to administer while maintaining high levels of sensitivity and specificity. Since immunohistochemistry (IHC) includes most of these features, its sensitivity, specificity, predictive positive value (PPV) and predictive negative value (PNV) for West Nile virus (WNv) screening were compared to those of the gold standard, RT-PCR testing of kidney tissue in dead birds.

Methodology: IHC and RT-PCR were performed for WNv antigen on 41 dead birds (belonging to five orders) collected from the northwest region of the Riverside County of California.