Agusto Folashade B, Atsu Joshua, Kwarteng-Adjei Dorothy, Lamptey-Mills Daniel, Osei Samuel A
University of Kansas, Lawrence, Kansas, United States of America.
North-West University, Potchefstroom, South Africa.
PLoS One. 2025 Aug 11;20(8):e0329465. doi: 10.1371/journal.pone.0329465. eCollection 2025.
Tularemia is a zoonotic disease caused by Francisella tularensis bacteria, a gram-negative coccobacillus-shaped bacterium. There are multiple transmission routes of the infection to humans such as consumption of contaminated food or water, handling of infected animals or bites from haematophagous arthropods (such as ticks, deer flies, or mosquitoes). In this study, we focus on transmission via the bites of ticks and developed a deterministic model of ordinary and impulsive differential equations to gain insight about the differential effect of prescribed fire on Dermacentor variabilis and Amblyomma americanum ticks and the prevalence of tularemina. We found that prescribed fire differentially reduce the number of the two ticks with A. americanum reduced the least compare to D. variabilis subsequently leading to differential increase of tularemia new infected cases in humans and rodents. Our result further indicates that the spatial arrangement of burn against unburn areas may not matter for humans and D. variabilis unlike A. americanum and the rodents which had more infected in unburn areas compare to burn areas when prescribed fire was implemented. The results of this study provide important new understandings of the intricate effect of prescribed fire on tick species, and the dynamics of the tick-borne disease.
兔热病是一种由土拉弗朗西斯菌引起的人畜共患病，土拉弗朗西斯菌是一种革兰氏阴性球杆菌。该感染向人类的传播途径有多种，如食用受污染的食物或水、处理受感染的动物或被吸血节肢动物（如蜱、鹿虻或蚊子）叮咬。在本研究中，我们关注通过蜱叮咬的传播方式，并建立了一个由常微分方程和脉冲微分方程组成的确定性模型，以深入了解规定火烧对变异革蜱和美洲钝缘蜱的不同影响以及兔热病的流行情况。我们发现，规定火烧对两种蜱的数量有不同程度的减少，其中美洲钝缘蜱减少的数量最少，相比之下变异革蜱减少得更多，这随后导致人类和啮齿动物中新感染兔热病病例的不同程度增加。我们的结果进一步表明，与美洲钝缘蜱和啮齿动物不同，对于人类和变异革蜱而言，火烧区域与未火烧区域的空间布局可能并不重要，当实施规定火烧时，未火烧区域的美洲钝缘蜱和啮齿动物的感染情况比火烧区域更为严重。本研究结果为规定火烧对蜱类物种的复杂影响以及蜱传疾病的动态变化提供了重要的新认识。
