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Mississippi insects can carry diseases
MISSISSIPPI STATE -- In a state where insects outnumber humans, it may be surprising that only a few Mississippians get sick every year from diseases carried by insects.
Dr. Mike Williams, entomologist with the Mississippi State University Extension Service, said the best way to avoid getting an insect-borne disease is to prevent pests from biting.
"Watch the time of day you're outside and wear insect repellant," Williams said. "There are some diseases that are possible to get from insects we have in Mississippi."
Ticks and mosquitoes are the most common carriers of disease in the state, but not all of them transmit diseases.
Dr. Jerome Goddard, state medical entomologist with the Mississippi Department of Health, said Rocky Mountain spotted fever carried by ticks and encephalitis carried by mosquitoes are the state's biggest insect threats to human health.
Goddard said there are about 30 cases a year of Rocky Mountain spotted fever in Mississippi, and a few die of the disease each year. Lyme disease, also carried by ticks, affects about 25 Mississippians a year, but isn't fatal. Encephalitis does not strike every year, but when it does, some cases are fatal.
"The thing that is a little scary about encephalitis is that in the mid 1970s, there was a big outbreak of St. Louis encephalitis. The state had 300 cases and 36 deaths from the disease," Goddard said. "We haven't had anything like that outbreak since then."
The symptoms of encephalitis can be treated, but not the disease itself. Goddard said an infected person's body either fights it off on its own or dies. Fortunately, most survive.
To prevent mosquito bites, Goddard suggested wearing long pants and long sleeves when outdoors after dark. An insect repellant with a 10 to 60 percent concentration of the active ingredient DEET is very effective at warding off mosquitoes when applied according to label directions.
To avoid ticks, use repellant and tuck pant legs into boots or socks when outdoors in high weed areas. This makes ticks crawl up the outside of clothes so they can be spotted and removed.
"If you do get bit but get the tick off within about 24 hours, you're fairly safe," Goddard said. "Prompt removal of ticks is a great deterrent to disease."
Goddard said most ticks are not carrying a disease, but a bite still can cause an allergic reaction in humans. These reactions can include itch and swelling at the bite area as the body reacts to the tick's saliva. A fever or unexplained illness that appears up to a month after a tick bite can indicate a tick-borne disease.
"The diseases ticks carry are treatable with antibiotics," Goddard said. "The key is recognizing the symptoms and treating it early."
There are other dangerous insects that sting and bite. Goddard said if a person is not allergic to bee stings, it would take several hundred stings before the person would die of the venom. But to someone who is allergic to the sting, even one can kill.
"A lot of what people think are allergic reactions to such things as fire ants are some sort of local complication or reaction," Goddard said. "There are various levels of allergic reactions, such as local swelling or an arm or a leg swelling up after a bite or sting."
Stinging caterpillars, the blister beetle, and brown recluse and black widow spiders also can be found in Mississippi. The caterpillars and beetles are painful but not usually serious, and Goddard said both spiders are rarely fatal.
"The black widow bite is a neurotoxin and makes you sick all over. You have muscle cramps, nausea, pain and fever that sends you to the hospital for a day or two," he said. "The brown recluse can be systemic and affect the whole body, but it's usually just local, killing a spot of tissue the size of a dime or quarter where the venom went in."
While these insects are out there, they do not pose an ever-present threat.
"A very small portion of insects are in any way dangerous," Goddard said. "We need to respect them and avoid the ones that cause harm, but we don't need to go out and kill all bugs."