An estimated 2,000 to 20,000 human cases of anthrax occur globally each year:

·       A major outbreak involving nearly 10,000 cases (most of them cutaneous infections) occurred in Zimbabwe during the late 1970s and early 1980s. An epizootic outbreak in cattle occurred at that time in the same area.

·       An outbreak involving nine cases (five inhalational and four cutaneous) occurred in 1957 in the United States in a New Hampshire goat-hair processing plant. This was the last recognized outbreak of naturally occurring infection in that country.

·       An outbreak of oropharyngeal anthrax involving 24 cases occurred in Thailand in 1982 following consumption of contaminated meat. Oropharyngeal disease is an unusual manisfestation of the infection, which makes this outbreak of particular interest.

Between 1984 and 1993, only three cases of cutaneous anthrax were reported to the Centers for Disease Control. A fatal case occurred in 1976, when a home craftsman died of inhalational anthrax after working with yarn imported from Pakistan. In the early 1900s, approximately 130 cases occurred annually in the US. The incidence has gradually declined over time, with less than 10 cases reported each year since the early 1960s.

Only 18 cases of naturally occurring inhalational anthrax were reported in the US during the 20th century, with the most recent case in 1976. All but three were associated with industrial exposures; two of the remaining cases were laboratory-acquired and the source of exposure for the third case remains unknown. Since 1990, only two cases of naturally occurring infection have been reported in the US (one in 1992 and one in 2000); both patients had the cutaneous disease. The latter case occurred in North Dakota and resulted from agricultural exposure.

8    More about anthrax in agriculture and its history