Section Veterinary Public Health, Department of Paraclinical Science, Faculty of Veterinary Sciences, University of Pretoria, Pretoria, South Africa.
Department of Agriculture and Animal Health, College of Agriculture and Environmental Sciences, University of South Africa, Florida Science Campus, Johannesburg, South Africa.
PLoS One. 2018 Oct 24;13(10):e0204758. doi: 10.1371/journal.pone.0204758. eCollection 2018.
Although anthrax is endemic in Lesotho, limited information is available on the patterns of the disease among livestock animals. This study investigated temporal patterns of anthrax outbreaks and cases among livestock animals in Lesotho.
Secondary data of anthrax outbreaks reported to the Department of Livestock Services between January 2005 and December 2016 was used for this study. Proportions of anthrax outbreaks and cases, and their corresponding 95% confidence interval were calculated and compared across year, season, month and region using the Chi-square or Fisher's exact test. The autoregression model was used to evaluate annual trends of anthrax outbreaks and cases.
A total of 38 outbreaks were reported in the Lowlands districts of Lesotho. District was significantly (p<0.0001) associated with outbreaks and cases, with the highest proportions of outbreaks (52.6%) and cases (70.2%) reported in Maseru. Significantly (p = 0.0004) higher proportions of anthrax outbreaks (78.9%) and cases (95.1%) were reported in the rainy-hot season compared to the dry-cold season. Five hundred and twenty-six (n = 526) anthrax cases were reported with significantly (p<0.0001) higher proportion of cases (70.3%) in cattle compared to other species. Higher proportion of anthrax cases (35.9%) were reported in 2008 and during the months of February (30.8%) and April (30.2%). There was no significant annual trend in anthrax outbreaks (r = 0.0282; p = 0.6213) and cases (r = 0.0873; p = 0.3512) over the study period.
The burden of anthrax in Lesotho is significantly higher in cattle. Anthrax outbreaks occur only in the lowland districts and follow a seasonal pattern. Therefore, more effort should be targeted at curbing the disease in cattle and the lowlands districts. Furthermore, there should be heightened monitoring of cases in the rainy season to ensure that resultant carcasses are disposed of appropriately to minimise future outbreaks.
炭疽在莱索托流行，但有关家畜炭疽病的流行模式的信息有限。本研究调查了莱索托家畜炭疽暴发和病例的时间模式。
本研究使用了 2005 年 1 月至 2016 年 12 月期间向家畜服务部报告的炭疽暴发的二级数据。使用卡方检验或 Fisher 精确检验比较了各年、各季节、各月份和各地区炭疽暴发和病例的比例及其相应的 95%置信区间。使用自回归模型评估炭疽暴发和病例的年度趋势。
共报告了莱索托低地地区的 38 起暴发。地区与暴发和病例显著相关（p<0.0001），马塞卢报告的暴发比例最高（52.6%）和病例比例最高（70.2%）。与干冷季节相比，雨热季节报告的炭疽暴发（78.9%）和病例（95.1%）比例显著更高（p = 0.0004）。报告了 526 例炭疽病例，与其他物种相比，牛的病例比例显著更高（70.3%）（p<0.0001）。2008 年和 2 月（30.8%）和 4 月（30.2%）报告的炭疽病例比例更高。在研究期间，炭疽暴发（r = 0.0282；p = 0.6213）和病例（r = 0.0873；p = 0.3512）没有显著的年度趋势。
莱索托的炭疽负担在牛中显著更高。炭疽暴发仅发生在低地地区，且呈季节性模式。因此，应更加努力控制牛和低地地区的疾病。此外，应加强雨季病例监测，以确保妥善处理由此产生的尸体，尽量减少未来的暴发。
