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Show Flooding increases t Directf of rnoscguio-boriie disease Because of record flooding, a real Ability exists for an outbreak of Luito-borne Western Equine Cephalitis in the Uintah Basin dur-the dur-the latter part of the summer, said "t sieve Romney , director of the Uin-jjj Uin-jjj County Mosquito Abatement District. e record flooding of the major nver drainages throughout the coun-L coun-L and adjacent areas, Dr. Romney L have to date, inundated many 'Jands of acres of land, which if op-jjial op-jjial conditions persist through July md August will provide breeding mis for tremendous population of Se encephalitis mosquito, Culex tarsal tar-sal as well as several other species of mosquitoes which occur in Uintah County. Dr. Romney stresses that the poten-lialfor poten-lialfor the disease, commonly called sleeping sickness, is high but that an outbreak this summer is by no means certain. "It's not the time to panic, but it (ouldget exciting late this summer," Or. Romney said. i Several environmental, as well as otter conditions must be met before extensive transmission of the viral disease to horses (and other animals) or humans will occur. In August and September of 1978, over sixty cases of encephalitis were professionally diagnosed in Uintah Basin horses. The natural reservoir of the encephalitis virus is wild and domestic bird populations, including groups of certain passarines or song birds and chickens. For encephalitis to be transmitted via a mosquito bite to horses or humans, the mosquito vector, or carrier car-rier of the disease must first have acquired ac-quired the virus by obtaining a blood meal from an infected bird host. The Uintah County Mosquito Abatement Abate-ment District is currently maintaining a sentinel chicken flock for the purpose pur-pose of monitoring the relative degree of local encephalitis virus activity. Blood samples are regularly taken from the birds and are analyzed at a Salt Lake City laboratory. "Any sudden increase in virus antibody an-tibody levels in the birds would provide pro-vide valuable early warning of greater disease threat to local horses and possibly humans," Dr. Romney said. Several other Utah mosquito abate- ment districts are maintaining sentinel sen-tinel chicken flocks for the same purpose. The Uintah County District is also maintaining a county-wide adult encephalitis mosquito sampling system employing specially designed mosquito light traps. Mosquito surveillance with the light traps is being accomplished through cooperative participation with the Utah Mosquito Abatement Association Encephalitis Surveillance Program. The Cluex tarsalis, the mosquito species capable of transmitting Western Equine Encephalitis in Utah, is only one of fifty species found in the state. The other 49 species in Utah are incapable of transmitting disease to humans or livestock. The encephalitis mosquito bits only in the hours ; around sunset to sunrise, while ' most of the other Uintah County species will bite on a 24-hour basis. Precaution As an important precautionary measure, it is urged that basin area horse owners contact their local veterinarians for information and recommendations concerning the readily available, inexpensive and highly effective vaccinations and booster shots for their animals, Dr. Romney said. The Abatement District is currently current-ly operating at full capacity in its county-wide fight against mosquitoes mos-quitoes it employes eleven seasonal field operators who are responsible for effective mosquito control over an infested in-fested area of about 1500 square miles. Dr. Romney emphasized the fact that all abatement personnel are stringently trained in modern theory and techniques of mosquito control and are trained, licensed and certified -by law prior to engaging in active : abatement procedures. Continued on page 2 :-" - - "t r "f V ." . x , - I V"""'" ' ; -' '"; WHAT DOES A CHICKEN and a mosquito have in common? Both creatures carry equine encephalitis. An increase potential for the disease that effects mostly horses, has spurred the Uintah County Mosquito Abatement to maintain an experimental flock of chickens to monitor the disease. Mosquito ... Continued from page 1 People Can Help The people of Uintah County can play an important role in helping control con-trol mosquitoes. A great percentage of the county's mosquitoes are produced on flood irrigated land. The basic sequence se-quence of production of several species of highly troublesome pasture mosquitoes begins when the female mosquito lays her eggs on the soil in a moist or muddy field or other similar habitat. The eggs, about 150 per individual in-dividual female, will hatch only if they are flooded by fresh water, and if necessary, can lie dormant in a dried condition for up to two or three years.-On years.-On being flooded, the eggs may begin to hatch into swimming larvae within minutes. One acre of irrigated land may produce as many as 12 million mosquito larvae in a single generation. The millions of swimming mosquito larvae can complete their growth and development and advance to flying biting adults in as little as four days at summertime temperature. The encephalitis mosquito is even more versatile in its reproductive capacities. In addition to breeding in irrigated fields or other large flooded areas, females will readily lay eggs in water-filled artificial containers such as discarded automobile tires, cans or rain barrels. "A water-filled cola bottle may even produce significant numbers of encephalities mosquitoes," Dr. Romney said. Aquatic larval stages of all mosquitoes mos-quitoes die when deprived of water. Dr. Romney requested that people make every effort to remove standing water from irrigated fields and other sources within four days of having been flooded and where possible to empty outdoor containers which may be unnecessarily filled with water. Dr. Romney welcomes persons to contact the Uintah County Mosquito Abatement Abate-ment if they have any questions regarding regar-ding mosquitoes, or have special problems pro-blems related to mosquito control. |