Map Reveals 32 States Where Dog Owners Warned of Common Tick-Borne Disease

Dogs are becoming more vulnerable to Lyme disease, veterinarians have said, and it is spreading throughout the U.S.

Veterinarians from the Virginia-Maryland College of Veterinary Medicine have warned that the tick-caused illness is spreading in not only humans but also dogs.

Lyme disease is spread through the bites of ticks infected with the Borrelia burgdorferi bacteria. According to PetMD, between 1.4 percent and 13.3 percent of dogs in the U.S. contract the disease. However, these numbers could rise as dogs become more vulnerable, the veterinarians warned.

The disease has usually been contained to the northeast of the U.S., but canine Lyme disease has now been detected in 32 states, said Jenny Marin, a clinical assistant professor at the college's Veterinary Teaching Hospital.

A map created by Newsweek shows the states where the disease poses a risk.

"Black-legged ticks, also called deer ticks, are most common carriers of Borrelia burgdorferi and can be found in the northeastern and north-central parts of the U.S. The western black-legged tick is found on the Pacific Coast," Marin told Newsweek.

Though the disease can be spread throughout the year, dogs commonly contract it in early spring and late autumn, when ticks are typically most active.

The main symptoms dog owners should watch out for include swollen lymph nodes, a fever, lethargy, loss in appetite, joint pain and increased thirst, and subsequent urination, the college reported. However, these symptoms may not manifest until months after a tick bite.

Lyme disease can be fatal if left untreated, as it can cause serious damage to the nervous system, heart and kidneys. It can leave lasting kidney damage, and its effects on the nervous system can cause seizures. Treatment is available and can cure the disease if given promptly.

"Dogs produce antibodies four to six weeks after infection, which can be detected through testing. Lyme disease is treated with antibiotics for typically a month. While antibiotics are effective in most cases, it's critical to complete the entire course of treatment, even if symptoms improve, to prevent the recurrence of the disease and reduce the risk of complications. Most symptoms clear up quickly with antibiotic treatment," Marin said.

Canine Lyme disease vaccines are also available. Some veterinarians may recommend vaccination depending on how often a dog is exposed to ticks.

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