Dto. de Ecología, Genética y Evolución, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos Aires, Ciudad Autónoma de Buenos Aires, Argentina.
Instituto de Ecología, Genética y Evolución de Buenos Aires (IEGEBA), UBA-CONICET, Ciudad Autónoma de Buenos Aires, Argentina.
Zoonoses Public Health. 2020 Dec;67(8):903-912. doi: 10.1111/zph.12777. Epub 2020 Oct 28.
A rodent survey was conducted in different landscape units of the city of Buenos Aires (Argentina) to determine the prevalence of Cryptosporidium and Giardia in Rattus norvegicus and to, ultimately, assess the biotic, environmental and meteorological factors that explain the variations of the likelihood of infection for both parasites in an urban environment. The results of this study revealed a ubiquitous presence of Cryptosporidium and Giardia in R. norvegicus within an urban environment with the likelihood of infection depending on environmental and meteorological conditions for both parasites. The overall prevalence was greater for Cryptosporidium (p = 50.4%) than for Giardia (20.3%). The prevalence for both parasites separately was higher in parks compared to shantytowns and scrap metal yards. Generalized Linear Mixed Models revealed that the occurrence of these parasites separately, at an individual level, was positively related with rainfall variables and that the effect of temperature depended on the landscape unit. The similarities in the transmission modes, which are affected by common extrinsic factors, may facilitate the co-occurrence of Cryptosporidium and Giardia in urban rats. Rattus norvegicus is recognized as a good model for epidemiological studies and the results of this work suggest that, from an epidemiological point of view, the probability of contact with infectious oocysts and cysts of these parasites can be modulated through environmental management and healthy behaviour towards risk factors. The information presented here will be useful to improve the understanding of the dynamics of zoonotic diseases within urban environments and to contribute to the decision-making of new and effective prophylactic measures.
对布宜诺斯艾利斯市（阿根廷）不同景观单元中的啮齿动物进行了调查，以确定挪威鼠体内隐孢子虫和贾第虫的流行率，并最终评估生物、环境和气象因素对两种寄生虫在城市环境中的感染可能性变化的解释。本研究结果表明，在城市环境中，隐孢子虫和贾第虫在挪威鼠体内普遍存在，感染的可能性取决于两种寄生虫的环境和气象条件。隐孢子虫的总流行率（p=50.4%）高于贾第虫（20.3%）。与棚户区和废金属场相比，公园中两种寄生虫的单独流行率更高。广义线性混合模型表明，这些寄生虫在个体水平上的单独发生与降雨变量呈正相关，而温度的影响取决于景观单元。由于受共同外在因素影响的传播模式相似，可能会促进城市老鼠中隐孢子虫和贾第虫的共同发生。挪威鼠被认为是流行病学研究的良好模型，这项工作的结果表明，从流行病学的角度来看，通过环境管理和对危险因素采取健康行为，可以调节接触这些寄生虫传染性卵囊和囊的概率。这里提供的信息将有助于提高对城市环境中动物传染病动态的理解，并为制定新的有效预防措施提供决策依据。
