• Anthrax in Africa
• Anthrax in Russia
• Anthrax in Australia
• Anthrax in Canada

Anthrax in Africa Outbreaks in South Africa Anthrax outbreaks are common for the people and animals native to many parts of South Africa, in particular the Kruger National Park where several outbreaks of anthrax have been reported in wild animals. Based on observational evidence, Southern Africa has been postulated by investigators like Smith et al to be the geographic origin of Bacillus anthracis.

Both the A type and B types of Bacillus anthracis have been identified in Southern Africa making south Africa as a world wide hot spot for genetic diversity of B anthracis. In a recent study carried out by Smith et al, Kruger B isolates were found to be present in higher concentrations in higher calcium and higher pH soils as compared to Kruger type A.

Other outbreaks in South and Central Africa
Lindeque and colleagues have analysed the epidemiology of anthrax outbreaks in Etosha National Park. According to their observations, outbreaks of anthrax peak in November at the end of the dry season. They have also reported a greater preponderance for males with mortality rates higher in males. The researchers found 3.3of 92 water and 3.0of 230 soil samples collected at different times of the year from 23 sites not associated with known cases of anthrax to be positive. However during an outbreak as much as a third of the water samples tested positive. The role of scavenger faeces was also examined. More than 50% of vulture, jackal and hyaena faeces collected from the vicinity of confirmed anthrax carcasses yielding B. anthracis, sometimes in substantial numbers, while no spores were found in faeces not associated with known anthrax carcasses.

Anthrax outbreak in cheetahs
In 1990, Jager et al reported that five cheetahs (Acinonyx jubatus) on a farm in the Gobabis district in Namibia died of anthrax. The mode of infection was believed to be a freshly shot baboon (Papio ursinus) with a cutaneous anthrax lesion.

Anthrax in hippopotamus
In another outbreak, in Zambia, Turnbull et al reported an abnormally high mortality of more than 4000 deaths among hippos in the Luangwa River valley between June and November 1987 .Cape buffalo (Syncerus caffer) and elephant (Loxodonta africana), were also affected. A year later, a smaller outbreak of anthrax in hippos was reported about 100 kilometres from the site of 1987.

Awareness about anthrax among the local population in outbreaks in West Africa
In west Africa, one survey carried out by Opare et al at the School of Public Health, University of Ghana revealed that despite the widespread occurrence of both animal and human anthrax in the region, awareness about the disease is still quite poor. To examine awareness about anthrax Opare et al carried out a study in the Tamale municipality of northern Ghana. In their study, 96 of the respondents, made up of 50 cattle owners, 50 herdsmen, 25 butchers and 125 consumers, knew of anthrax and the clinical signs indicative of anthrax in cattle. A significant percentage of individuals who participated in the study ascribed the occurrence of the disease to the supernatural and few were aware about the exact aetiology. 8% of the respondents felt that herbal preparations could protect against human anthrax. The study revealed that a significant proportion of respondents felt that animals, which had died of unknown causes could be eaten, especially if the meat was cooked with herbs believed to prevent anthrax.

Anthrax in Russia Preparation of database of anthrax foci zones in Russia In the USSR of former times, early in 20th century, the incidence of anthrax was almost as bad as the plague. As much as 40-60 000 cases of anthrax were annually reported in domestic animals. In humans the incidence was reported to be about 10-20 000 with a 25% mortality rate.

Cherkasskiy, a Russian epidemiologist has carried out a study to map all the anthrax zones in Russia. Funded by the International Technical and Scientific Center in Moscow, the investigative effort is aimed at collection of all data of known anthrax foci, including the village name, agricultural council, region, and year of occurrence.

The objective is to assemble a reference handbook, "Register of stable anthrax sites in the Russian Federation", with organized information on more than 10 000 anthrax foci responsible for outbreaks in the past 100 years. Using Geographic Information System (GIS), the plan is to map and correlate anthrax zones with natural geographic features, like soil type, climate, etc in order to make valid predictions using computational methods of analysis.

Leak of Anthrax spores from a military base
A large epidemic of anthrax that occurred in Sverdlovsk (now Ekaterinburg), Russia, in 1979 resulted in the deaths of many persons. Several investigators, e.g. Meselson et al cite the outbreak of anthrax to the inhalation of spores accidentally released at a military microbiology facility in the city. Epidemiological data show that most victims worked or lived in a narrow zone extending from the military facility to the southern city limit. As many as 42 deaths were reported. Post mortem reports were diagnostic of inhalation anthrax, i.e. hemorrhagic necrosis of the thoracic lymph nodes in the lymphatic drainage of the lungs and hemorrhagic mediastinitis. Bacillus anthracis was recovered in bacterial cultures of 20 cases, and organisms were detected microscopically in infected tissues of nearly all of the cases. According to Abrarnova, a novel observation was primary focal hemorrhagic necrotizing pneumonia at the apparent portal of entry in 11 cases. Mesenteric lymphadenitis occurred in only 9 cases.

Anthrax in Australia Vaccination during an epidemic helps! In the summer of 1997, anthrax occurred on 83 properties in an area of north central Victoria between 26 January and 26 March. Anthrax had not been recorded in the outbreak area since records were initiated in 1914, although anthrax did occur in the general area in the 1880s to 1890s.

According to Turner et al, vaccination helped to bring down the mortality quite significantly in the latter months of 1997 and subsequent years.

He observed that the spread of the disease was greatly limited by the creation of a vaccination buffer zone 30 km by 20 km. As many as 78, 649 cattle in 457 herds were vaccinated in a three week program. Turner reports that in the 10 days following vaccination 144 cases of anthrax were reported and 38 cases occurred more than 10 days after vaccination. However, during revaccination in October and early November 1997,only two confirmed cases of anthrax in vaccinated seven and nine month old calves were reported in the following anthrax season.

Anthrax in Canada Pattern of anthrax outbreaks in Canada From 1900 - 1950, anthrax outbreaks in Canada were reported in the southern portions of Ontario and Quebec.

At that time, it was believed that outbreaks of anthrax occurred due to pastures contaminated by effluent from textile industries dealing with imported animal materials.

However, since 1952, when federal regulations made it mandatory that such materials be disinfected prior to use, the incidence of anthrax declined drastically in eastern Canada. Since 1962, domestic outbreaks of the disease have been reported almost exclusively in cattle in the western prairie provinces. According to Dragon, between 1962 & 1993, nine anthrax epizootics have been recorded in the bison herds of the Northwest Territories and northern Alberta causing deaths of at least 1309 animals.

Conclusive evidence for anthrax spore reservoirs in scavenger faeces and anthrax carcass sites
In another study carried out by Dragon et al, the levels of anthrax spore contamination in endemic regions of northern Canada between outbreaks was determined. The investigators observed that of 588 environmental specimens collected, 11 (1.9%) contained viable anthrax spores.High concentration of anthrax spores in northern Canada appear limited to scavenger faeces and anthrax carcass sites. Burial and cremation appear equally effective at removing anthrax spores from the immediate environment. This study describes an effective anthrax spore detection system.

Anthrax carcass location in outbreak using air borne infrared sensing camera
In July 1993 an outbreak of anthrax causing high mortality in an isolated, free-ranging population of bison (Bos bison athabascae) west of Great Slave Lake occurred in the Northwest Territories of Canada. Gates et al report that 172 bison, 3 moose (Alces alces), and 3 black bear (Ursus americanus) carcasses were found. The carcasses were found using an airborne, remote infrared sensing camera mounted externally on a helicopter. Fifty-five percent of the carcasses were located in forested or shrub-covered sites where detection would not have been likely without the thermal imaging equipment.

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