Risk Factors Associated with Anthrax Outbreak in Animals in North Dakota, 2005: A Retrospective Case-Control Study

Abstract

SYNOPSISObjective. We identified the risk factors associated with the anthrax outbreak of 2005 in animals in North Dakota.Methods. Medical records of the 2005 anthrax outbreak were obtained from the Veterinary Diagnostic Laboratory at North Dakota State University. Additional data were obtained from the North Dakota state veterinarian's office, and supplemental questionnaires were administered to producers. The data obtained included ecological and environmental factors, animal health factors, and management factors.Results. Anthrax occurred from July 1 to October 12, 2005. The cases were located in eastern North Dakota around the Red River Basin. Ransom, LaMoure, and Barnes counties reported most cases (71%). Species affected included cattle, bison, horses, sheep, elk, deer, pigs, and llamas. The predominant symptom was sudden death (38%) followed by bleeding from orifices (17%). Chi-square analysis indicated significant differences between case and control premises on the following variables: death reported on neighboring pasture, vaccination period, dry conditions, wet conditions, antibiotic use, multiple vaccination, and type of predator (coyote). Factors that significantly (p,0.05) predicted anthrax occurrences on the final logistic regression model were vaccination, use of antibiotics during an outbreak, and period of vaccine administration (before or during the outbreak).Conclusions. The characteristics of the anthrax outbreak regarding time and place of occurrence, animals affected, clinical signs reported, and mortality rate were consistent with previous reports of natural anthrax outbreaks in animals. A number of factors that significantly predicted anthrax occurrence in animals in the 2005 outbreak in North Dakota were identified. This information is important in planning appropriate control and prevention measures for anthrax, including recommending the right vaccination and treatment regimens in managing future anthrax outbreaks.

Soil ingestion, nutrition and the seasonality of anthrax in herbivores of Etosha National Park

“…Anthrax outbreaks occur world-wide and are of concern for animal conservation (Leendertz et al 2004, Muoria et al 2007), wildlife management (Clegg et al 2007, Wafula et al 2008, agriculture (Mongoh et al 2008, Durrheim et al 2009, Lewerin et al 2010) and public health (Siamudaala et al 2006). Anthrax is caused by the bacterium Bacillus anthracis which can infect a wide range of animal species, but mortalities are most commonly observed in herbivorous mammals.…”

“…The timing of anthrax outbreaks within a particular locality tend to have a seasonal signal, although the season during which most cases occur varies from locality to locality. Outbreaks consisting primarily of grazing wildlife or livestock occur in seasonal or weather conditions along a spectrum from drought (Fox et al 1977, Shiferaw et al 2002, Muoria et al 2007, Wafula et al 2008, Hampson et al 2011, to hot dry seasons often following years of unusually high rainfall (Rees et al 1977, Gates et al 1995, Dragon et al 1999, Turner et al 1999, Himsworth and Argue 2008, Chikerema et al 2012, to transition periods between dry-wet or wet-dry conditions (Fox et al 1973, Parkinson et al 2003, Siamudaala et al 2006, Mongoh et al 2008, to wet season outbreaks (Lindeque and Turnbull 1994, Durrheim et al 2009, Chikerema et al 2012. Some authors do not specify the time scale in which the described weather patterns occur in relation to the outbreak.…”

Spatial methods for infectious disease outbreak investigations: systematic literature review

“…Although the simple dot map was the most commonly used method, a wide range of techniques were applied, including more sophisticated data visualisations and analytic tools. Across the range of studies, there were examples of spatial tools being usefully applied throughout the course of an outbreak investigation; from initial confirmation of the outbreak to describing and analysing [11,18-28,30-36,38,40-50,55,56,58-60, 63,67-69,71-76,80,82-85,87-93,96-105] Thematic map 25 [18,19,[21][22][23]28,29,38,41,42,45,46,50,60,68,70,74,80,82,89,91,[93][94][95]103] Rate map 14 [20,30,44,45,49,50,57,63,70,76,79,81,90,101] Smoothed incidence map 13 [11,31,[48][49][50]73,…”

Growth inhibition of the zoonotic bacteria Bacillus anthracis by high antioxidant Australian plants: New leads for the prevention and treatment of anthrax

“…Sizeable recent outbreaks have been reported in China in 2012, 8 in India in 2011 9 and 2014, 10 in Canada in 2006 11 and in the United States in 2005. 12 There have also been reports of anthrax amongst European heroin users, with reported cases in Denmark, England, France, Germany, Norway and Scotland. 13 The threat of anthrax outbreaks via bioterrorism has also received much recent attention following multiple cases of inhalational anthrax in the United States resulting from intentional release of B. anthracis spores.…”