Protect Your Family From West Nile Virus
West Nile Virus (often abbreviated as, WNV) is a virus that is normally carried by female mosquitoes and when its transmitted or passed on to humans, it can lead to severe encephalitis. WNV is related to the Saint Lous Encephalitis virus (abbreviated as, SLEV). WNV was 1st isolated in the year 1937, from a female patient in West-Nile province, Uganda in East-Africa. Epidemics of the West Nile Virus have been experienced in France, Israel, Romania and South Africa.The West Nile-Virus was 1st documented in New York (NYC), USA in an epidemic that occurred in August of the year 1999.
West Nile-Virus (WMV) Encephalitis and Human-West Nile-Fever
Most humans who’re infected with WNV don’t develop any clinical illness. About 20 percent of those who’re infected with WNV will exhibit symptoms like: headache, fever, body aches, swollen lymph-glands and skin rash. These symptoms are usually termed as the West-Nile Fever-Symptoms of WNV. This fever normally lasts for a few days. The more severe infections can include: high fever, headache, neck stiffness,coma, disorientation, convulsions, paralysis and general muscle weakness. The severe form of this infection is termed as West-Nile-encephalitis. About 1 out of every-150 human-infections usually result in encephalitis. West-Nile encephalitis can last for several weeks or even months. Some of those suffering from the West Nile-encephalitis may experience permanent-neurological-effects.
West Nile-Virus (WNV) in Horses
Horses that get infected with WNV will often exhibit some signs of ataxia ( that is, loss of muscle-coordination) which usually affects their rear limbs making them stumble, stagger, and have a wobbly gait. Some other related signs include: teeth-grinding, muscle-fasciculation, difficulty lying down and being unable to rise, facial-paralysis, blindness and twitching. The treatment of the infected horses is normally based on the clinical-signs with the aim of minimising the infection’s severity. Fluid and nutrient-supportive therapy is usually required. Horses are normally euthanized only when they’re suffering from severe-encephalitis and when they’re unlikely to recover.
How The Virus Gets Into Horses and Humans
The most common mode-of-transmission of the virus to horses and humans is through a bite from a WNV infected-mosquito. The mosquitoes normally obtain the WNV virus by biting on infected wild-birds.When a female mosquito feeds or bites on an infected wild bird, the virus typically goes through an incubation period inside that mosquito. At the end of the incubation period, the virus will then be passed on each time that infected mosquito feeds or bites on a vertebrate-host. Whenever the infected mosquito “blood feeds”, the WNV is usually mixed with the female mosquito’s-saliva and is released into the blood-stream of the 2nd-host. If the 2nd-host is susceptible-to WNV-virus, a clinical or a sub-clinical WNV-infection may result.
The mosquito-species that plays a major role in transmitting the WNV are the genus-Culex species. The Culex-species have often been implicated in the West Nile-outbreaks on most of the temperate and tropical world, and there’s evidence in Florida which indicates that Culex-nigripalpus is an major vector of the WNV. Females of the Culex species normally lay eggs in the flooded citrus-groves, sewers, catch basins, cisterns, and small water pools. The peak-time for their blood feeding is usually between sunset-and-sunrise with concentrated-blood feeding peaking immediately after sunset and just-before sunrise.
WNV was 1st-detected in Florida in a dead-crow that was collected on June-18, the year 2001. It’s likely that the WNV arrived in Florida the fall of the year 2000. The WNV was most likely within the birds that were migrating to the south from the countryside areas that had on-going WNV-transmission. Since the year 2001, various confirmed-cases of WNV in horses and humans have been reported almost every-year in Florida