The following information is taken from Merck Veterinary Manual 8th Edition, Editor Susan E Aiello, Published by MERCK & CO, INC, Whitehouse Station, NJ, USA, 1998 ISBN 0-911910-29-8, pg 432.
Epidemics [of anthrax] tend to occur in association with marked climatic or ecologic change, such as heavy rainfall, flooding, or drought. Even in endemic areas, anthrax occurs irregularly, often with many years between occurrences. During an epidemic, flies and other biting insects may mechanically transmit the disease from one animal to another, but this mode of transmission is of minor importance. In South Africa, nonbiting blowflies may contaminate vegetation by depositing vomit droplets after feeding on a carcass infected with B anthracis. This contaminated vegetation is believed to be an important source of infection for browsing animals such as kudu. Infection also may be caused by consumption of contaminated feedstuffs, eg, meat and bone meal. Occasionally, crops such as hay grown on contaminated soil have caused small outbreaks. Pigs, dogs, cats, mink, and wild animals in captivity have acquired the disease from consumption of contaminated meat.
Man may develop localized cutaneous lesions (malignant carbuncle) from contact of broken skin with infected blood or tissues, or acquire a highly fatal hemorrhagic mediastinitis (woolsorters' disease) from spore inhalation when handling contaminated wool or hair. Man may also acquire intestinal anthrax from consumption of undercooked meat.
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