According to Health Ministry data, 299 people in Israel have contracted the West Nile fever virus, with 15 of them dying as a result. However, the disease doesn't only affect humans but birds such as crows as well. Reports of birds exhibiting strange behavior have increased recently, with some subsequently dying. Birds can’t transmit the disease, however, only mosquitoes.
The Agriculture and Food Security Ministry’s Director of Veterinary Services Dr. Tamir Goshen addressed the infection of birds with West Nile fever in an interview with Ynet on Wednesday. "Birds, songbirds, and other wild avians infected with the virus also show neurological indicators and often die without prior symptoms," he said.
"It could be we’re seeing many positive cases in hodded crows in Israel recently due to the species-specific sensitivity to the virus. This phenomenon has also been documented in other types of crows in the U.S., who died suddenly from West Nile fever after being infected by mosquitoes."
Dr. Goshen noted the virus’ strain isn’t a new disease and that animals have been affected in previous breakouts as well. "We saw similar outbreaks for several decades now," he said. " There was an outbreak that severely affected humans in the late 1990s, with several dozen deaths which also severely affected horses."
He pointed out that, unlike humans, horses have a vaccine that likely provides immunity to the virus, which is why most horses are safe. "We haven't had cases in horses this year," Dr. Goshen said.
He also mentioned recent weeks have seen reports of dead birds or some with "neurological indicators," exhibiting strange behavior, which were brought to the veterinary institute and tested positive for West Nile fever. "In the past two months, 159 infected birds have been found compared to only three cases last year."
Dr. Goshen stressed there was no need to panic when seeing a bird behaving strangely. "We ask to be delivered the carcasses and report of deceased birds or those showcasing strange behavior," he said.
"It's not just songbirds; birds of prey can also become infected via the eating of carcasses. We see birds of prey, both diurnal and nocturnal, that have been brought in and tested positive for the virus. The Agriculture Ministry, in coordination with the Health and Environmental Protection ministries, is trying to connect the dots and understand where the virus is present in the country."
He described how you can identify if a bird is positive for the virus. "First of all, you find an abundance of bird corpses. This is the main and important thing," Dr. Goshen said. "The second thing is seeing birds walking in circles, spinning, falling, getting up, their head turned and showing neurological indicators related to the central nervous system."
"The main sign is usually in spotting many corpses,” he added. “A high density of birds was diagnosed seen between the Hadera and Ashdod area, but we already have reports on positive cases in birds found in the Jordan Valley area and other parts of the country."