A Kansas State University epidemiologist is helping cats, pet owners and soldiers stay healthy by studying feline tularemia, a serious problem for cats and their human friends in parts of the Midwest.
Ram Raghavan and his research team say that a certain combination of climate, physical environment and socio-ecologic conditions are behind tularemia infections among cats in the region. More than 50 percent of all tularemia cases in the U.S. occur in Kansas, Missouri, Oklahoma and Arkansas, Raghavan said.
Ticks, rabbits and rodents help spread the disease, which can also spread to humans through ticks and insect bites as well as through cat bites and scratches. If left untreated, tularemia can be fatal both to humans and animals.
If cats hunt outdoors or come into contact with an infected rabbit, insect or animal, they can bring tularemia back to their owners.
Raghavan's research so far has found that tularemia is more likely to appear:
- In newly urbanized areas.
- In residential locations surrounded by grassland.
- In high-humidity environments. Raghavan found that locations where tularemia was confirmed had high-humidity conditions about eight weeks before the disease appeared.
While tularemia is more common in young children and men, people also can get the disease when mowing lawns in a contaminated area, Raghavan said. Both human and feline tularemia cases peak through late spring and summer -- when the weather is warmer, more ticks are present and more people are outside. Tularemia cases decrease at summer's end.
"Climate plays such a huge role in zoonotic diseases," Raghavan said. "With all the talk about climate change, we need to know if there are any significant climate effects that are causing tularemia cases to increase."
A problem for the military
Tularemia also poses concerns for the military and soldiers during training exercises, whether they are training in U.S. bases or bases around the world. During training, soldiers are actively engaged in the environment and that increases the risk of tularemia infection.
"They could be crawling on the ground and may come in contact with a dead animal or rabbit that was infected with tularemia," Raghavan said. "The soldiers also can be bitten by ticks. All it takes is a few bacteria to cause infection."
Because of the low infection dose of organisms, it is even more important to understand tularemia because of its potential as a bioterrorism tool, Raghavan said.
"If a little of the bacteria was present in the form of an aerosol, it could be released in a crowded area and potentially infect a lot of people very quickly," Raghavan said. "Because it is such a rare disease, not everyone is prepared for it, even though the treatments are very simple. Untreated infections can cause death."
Symptoms of tularemia in humans may include fever, swelling of lymph nodes, skin ulcers near tick bites, or cough, chest pain and difficulty breathing in more serious cases. Clinical signs in cats include lethargy, anorexia and fever. People should contact their doctor or their veterinarian if they observe tularemia symptoms, Raghavan said.