Cases of West Nile Virus (WNV) in horses are starting to show up, with rising numbers in Texas and at least one confirmed in New Jersey.

There are now a total of 22 positive cases of WNV in horses from the previous 19 based on the confirmed serological tests from the Texas A&M Veterinary Medical Diagnostic Laboratory (TVMDL), The Horse reported.

The Texan counties with positive cases include Houston, Jefferson, Roberts, Randall, Hutchinson, Taylor, Robertson, and Midland among others. Each county has at least one horse testing positive for the virus. Jefferson had the most number of cases as of Oct. 5, recorded at three.

Meanwhile, Gloucester County in New Jersey also saw its first ever equine WNV case for this year. According to NJ.com, a 10-year-old gelding was put to death on Oct. 3 for testing positive with the virus.

Also, an Oct. 12 report from KEYT.com stated that WNV has been detected in dead birds in California, particularly Santa Barbara County.

The New Jersey horse's vaccine status is unknown, but most of the Texan horses that tested positive were not given vaccine against the virus.

This only suggests that giving vaccines to horses is important to help save their lives. Santa Barbara County officials are also calling on horse owners to give their animals the vaccine, according to KEYT.

West Nile Virus is carried by mosquitoes that transmit them by biting on their host. The virus specifically attacks the central nervous system but signs don't show up until five to ten days after being bitten by an infected mosquito. Signs include weakness in the limbs, muscle twitching, stumbling and possibly death.

Immediate treatment is important for a horse that has been infected by the virus. Currently, there's no specific drug for WNV in horses, but supportive treatment can be given by a veterinarian to help save the animal's life.

Last year, there were 141 cases of WNV in horses coming from 32 states. This number of cases is lower than in 2013 and significantly lower compared to the WNV outbreak in 2002, according to the Department of Agriculture.