Spores usually enter the body through a puncture wound contaminated with soil or manure. However, many human cases have followed injuries considered too trivial for medical attention and in some cases there is absolutely no record of a physical injury or wound. The incubation period is quite varied but averages 3-21 days. A common early sign suggestive of tetanus is abdominal rigidity. Prevention for personnel includes maintaining adequate vaccination and reporting any injury to the unit supervisor.
Transmission occurs through a bite, scratch or abrasion from an infected animal.
Farm animals usually are bitten by a rabid dog, coyote, cat, raccoon, skunk or bat, or an infected herdmate. Rabid animals of all species exhibit signs of central nervous system disturbances once they are past the early incubation stage. Unfortunately, an animal in the first stages of the disease may show no signs at all and yet still be infective. Sometimes, infected horses bite other animals or people at the slightest provocation and some infected cattle will butt objects or act like they have something caught in their throat. Report any bite wound or scratch to the unit supervisor.