Animal health officials working to prevent spread of ticks

Austin, Texas - 10/8/07 - A $13-million price tag is attached to an effort to eradicate the incursion of tiny fever ticks to a once tick-free five-county Texas area along the Mexican border, says livestock officials.

"For most of the country, the fever tick has been pushed out of sight, out of mind, since the 1940s," says Bob Tillman, DVM, Texas state veterinarian and executive director of the Texas Animal Health Commision , of the 1/8-inch long parasites, which can carry and transmit "babesia" - a blood parasite deadly to cattle.

"If we do not stop it, the fever tick could spread from coast to coast, except the arid lands of New Mexico and Arizona, and as far north as Washington D.C. As the tick spreads, so will the need for personnel and resources," Tillman says. "Win the battle along the Rio Grande in Texas, and other states won't have to fight the war."

More than 1,115 square miles in five Texas border counties - Starr, Zapata, Maverick, Dimmit and Webb - have been put under quarantine, in addition to an 852-square mile permanent quarantine zone that abuts the Rio Grande.

The U.S. Department of Agriculture's 60-person Fever Tick Force is currently managing the Delaware-sized zone while awaiting the addition of up to 30 temporary tick inspectors.

All cattle, horses, penned deer, llamas, camels and any other species that can host ticks are being manually inspected by TAHC and USDA inspectors.

"The USDA has made $340,000 available for immediate fever tick needs in south Texas, and the state legislature granted the TAHC an extra $150,000 to purchase additional Co-Ral, the acaracide used for dipping vats and in spray rings," Hillman says. He reported that a USDA assessment concluded that to eliminate fever ticks from the temporary preventative quarantine areas, at least $13 million was needed to hire additional personnel, repair or replace worn out portable tick dipping equipment, purchase new spray rigs and supplies and procure other essential equipment.

"The fever tick, by itself, will not cause disease. However, cattle tick fever is imminent if the fever tick is carrying babesia, and transmits it to cattle that are 'naive,' meaning they have no resistance to the organism that quickly breaks down red blood cells," Hillman says. "There are two potential scenarios with fever ticks that keep the TAHC, the Tick Force and border ranchers awake at night."

The first involves young calves being exposed to babesia in Mexico, surviving the disease and developing immunity while continuing to carry the disease, Hillman says. The second scenario involves wildlife as effective alternative hosts and sources for movement of ticks into Texas from Mexico and from the permanent quarantine zone to the free area of Texas. But the tick currently does not pose a threat to humans.

"The fever tick is not a human health threat," Tillman says. "But be careful. Don't transport ticks to new sites. Getting and keeping the fever tick outside of Texas and the U.S. is critical for disease control and our continued ability to move livestock without restrictions."