Most naturally occurring anthrax strains are susceptible to penicillins, and penicillins have been considered the first line of defense against anthrax. Anthrax spores have been isolated from the crops of sparrows, and birds of prey (e.g., vultures) have been implicated in the spread of anthrax spores through fecal contamination.
Because antibiotic treatment has been shown to interfere with response to the Sterne vaccine in animals, animals receiving concurrent antibiotic treatment should be revaccinated after the antibiotic regimen has been completed. Except when acquired by inhalation, B. anthracis needs a lesion through which to enter the body. Chest radiographs of patients suffering from respiratory ailments may also be diagnostic.Herbivores may become infected by ingesting spores while grazing in areas of high soil contamination or through the bite of certain flies. Carnivores (e.g., dogs, cats, lions) and omnivores (e.g., swine) may become infected by eating undercooked meat from infected animals; however, many carnivores appear to have a natural resistance. A complete risk assessment for direct contamination of food or water with anthrax spores is not available.Necropsies should not be performed on animals that are suspected to have died from anthrax, because decomposition of intact carcasses progresses rapidly and the vegetative (nonspore) form of B. anthracis is destroyed in a short time. Ulcerative lesions may be observed in the oral cavity and throat. The name is derived from the Greek word for coal, anthrakis, because the cutaneous form of the disease causes black, coal-like skin lesions. —Death usually occurs 1 to 6 days after illness onset, and 75% of patients die within 24 hr of presentation. Because antibiotic-resistant strains can be readily isolated in laboratories, experts have suggested that ciprofloxacin may be the drug of choice when terrorism is suspected as the source of B. anthracis, at least until antibiotic susceptibilities can be determined. Blood may fail to clot because of a toxin released by B. anthracis. If ingested, clinical signs include loss of appetite, colic, enteritis, fever, trembling depression, and bloody diarrhea. Animal vaccines have not been approved for and should not be administered to humans. Adjacent lymph nodes may be swollen and painful. Anthrax is more often a risk in countries with minimally effective public health programs.Cattle, sheep, and goats—Clinical signs of peracute anthrax in cattle, sheep, and goats include staggering, trembling, breathing difficulty, convulsions, and death. —A literature review of pediatric anthrax cases identified between 1900 and 2005 demonstrated an overall mortality rate for meningoencephalitis of 100% (6 of 6 cases).
Chronic anthrax is most often seen in less susceptible species such as swine, but it has also been reported as developing in cattle, horses, dogs, and cats.