Journal Name:
VECTOR-BORNE AND ZOONOTIC DISEASES
Volume:
17
Issue:
1
Pages From:
1
To:
9
Date:
Monday, June 19, 2017
Keywords:
horse, Israel, Palestine, serology, West Nile virus
Abstract:
West Nile virus (WNV) epidemiological situation in Israel and Palestine, due to their unique location, draws
attention following to the global spread of West Nile fever (WNF). Although much information is available
from Israel on clinical cases and prevalence of WNV, clinical cases are rarely reported in Palestine, and
prevalence is not known. The objectives of this study were to determine WNV seroprevalence in various
domestic animals in Palestine and to reevaluate current seroprevalence, force of infection, and risk factors for
WNV exposure in horses in Israel. Sera samples were collected from 717 animals from Palestine and Israel (460
horses, 124 donkeys, 3 mules, 50 goats, 45 sheep, and 35 camels). Two hundred and ten horses were sampled
twice. The level of WNV antibodies was determined using commercial Enzyme-linked Immunosorbent Assay
(ELISA) Kit. Seroprevalence in equids was 73%. Seroprevalence in Israel (84.6%) was significantly higher than
in Palestine (48.6%). Seroprevalence in horses (82.6%) was significantly higher than in donkeys and mules
(39.3%). Multivariable statistical analysis showed that geographical area, landscape features (altitude), environmental
factors (land surface temperature during the day [LSTD]), species, and age significantly influenced
WNV seroprevalence. Fourteen of 95 (14.7%) sheep and goats and 14/35 camels (40%) sampled in Palestine
were seropositive for WNV. Of the horses that were sampled twice, 82.8% were seropositive for WNV at the
first sampling, and all remained seropositive. Three of the seronegative horses, all from Palestine, converted to
positive when resampled (8.5%). The results indicate that domestic animals in Palestine were infected with
WNV in the past, and the seroconversion indicates that WNV was circulating in Palestine in the summer of
2014. Control measures to prevent human infection should be implemented in Palestine. Anti WNV antibodies
in domestic animals suggest that those species can be used as sentinels for WNV activity in areas where most
horses are either seropositive or vaccinated.
