Leave tularemia alone
The older I get, the less I enjoy the heat and humidity. Actually that was one of the reasons I left Iowa, to avoid the humidity. As I recall they called it ‘Corn Sweat,” but now we have expanded the corn belts into eastern South Dakota. Hopefully your animals withstood the extreme environmental issues and we have more moderate temperatures for the remainder of the summer.
This time of year with all of the mama cows in pasture we have little to talk about but the weather. Last week I received a question about a rare but important disease in South Dakota, Tularemia. The disease is caused by a bacteria, Francisella tularenis. Rodents like rabbits and prairie dogs a commonly infected and may die in large numbers during outbreaks. The health problem arises when these infected animals are huddled, and sometimes eaten by predatory animals. Cats are a primary problem in our area. If your cat or a feral cat becomes infected, it can also pass the disease to veterinarians, children, and other well purposed people attempting the help the diseased animal.
Tularemia (Rabbit fever) is a reportable disease in South Dakota for both animals and humans. In 2015 South Dakota Department of Health and Disease Summary recorded twenty-five (25) cases while the 5-year median is seven (7). That’s an increase of 257 percent. The cases were reported from May-August, the warmest months of the year. Twenty of the people infected were 40 years or older while 4 were children less than 15 years old. Geographically all cases were west of the James River with a vast majority, (90+ percent) in the west surrounding Rapid City. In 2016 the SD Dept. of Health has seven cases, All reported in western South Dakota.
Data from the SDSU Diagnostic Lab exhibits only 13 animals diagnosed on postmortem with Tularemia in the past five years. All are cats from clinics east of the Mission River except a wild cottontail rabbit in 2010 from Rapid City and a prairie dog from Rosebud in 2016. The human risk cannot be ever over-emphasized from this disease. Last year we had a cat brought to our clinic in Wagner for treatment. The animal’s tissues were eventually sent to SDSU and the result was Tularemia. Fortunately, none of our staff or the owner (good Samaritan) contracted the disease because of precautions implemented. About fifteen years ago our office manager was bitten by a cat during examination and spent several days in intensive care at the local hospital. We all must be very vigilant.
No one is sure why the cases have increased but there are several scenarios suggested:
· Small wild animal populations cycle. If the attacks on my garden are in indication, we are in a population increase for the cottontail rabbit. The reason for a decline in population would be disease like Tularemia, and then predators (cats) would encounter the disease while hunting.
· Tularemia is spread by ticks and deer flies. Last year was one the worst tick years I have seen. Flies have been tough this year also. Rodents tend to live in groups and can carry these parasites into their dens affecting whole towns.
o Tularemia is treated successfully with antibiotics, but it is best to eliminate contact with infected animals.
· Leave wild animals and their young alone. Don’t handle baby bunnies etc. and remind your children.
· Don’t allow cats to hunt and come in contact with infected rodents.
· Be very careful if playing good Samaritan to feral cats.
· If you cat becomes ill use care when transporting it to your veterinarian.
· If you suspect you have handled or been in contact with infected animals and are exhibiting flu-like symptoms, contact your physician immediately.
Pets and cute furry creatures in nature can be the source of human disease. If you have questions or problems, contact your veterinarian and your health provider. Thanks to Dr Russ Daly, SDSU extension and State Public Health Veterinarian for facts and statistics for this article.