Shocket Marta S, Bernhardt Joey R, Miazgowicz Kerri L, Orakzai Alyzeh, Savage Van M, Hall Richard J, Ryan Sadie J, Murdock Courtney C
Lancaster Environment Centre, Lancaster University, Lancaster, UK.
Department of Geography and the Emerging Pathogens Institute, University of Florida, Gainesville, FL, USA.
Nat Commun. 2025 Apr 11;16(1):3441. doi: 10.1038/s41467-025-58612-w.
Temperature shapes the geographic distribution, seasonality, and magnitude of mosquito-borne disease outbreaks. Models predicting transmission often use mosquito and pathogen thermal responses measured at constant temperatures. However, mosquitoes live in fluctuating temperatures. Rate summation--non-linear averaging of trait values measured at constant temperatures-is commonly used to infer performance in fluctuating environments, but its accuracy is rarely validated. We measured three traits that impact transmission-bite rate, survival, fecundity-in a malaria mosquito (Anopheles stephensi) across three diurnal temperature ranges (0, 9, and 12 °C). We compared transmission thermal suitability models with temperature-trait relationships observed under constant temperatures, fluctuating temperatures, and those predicted by rate summation. We mapped results across An. stephenesi's native Asian and invasive African ranges. We found: 1) daily temperature fluctuation trait values substantially differ from both constant temperature experiments and rate summation; 2) rate summation partially captured decreases in performance near thermal optima, yet incorrectly predicted increases near thermal limits; and 3) while thermal suitability across constant temperatures did not perfectly capture fluctuating environments, it was better than rate summation for estimating and mapping thermal limits. Our study provides insight into methods for predicting mosquito-borne disease risk and emphasizes the need to improve understanding of organismal performance under fluctuating conditions.
温度塑造了蚊媒疾病暴发的地理分布、季节性和规模。预测疾病传播的模型通常采用在恒定温度下测得的蚊子和病原体的热反应。然而，蚊子生活在温度波动的环境中。速率总和——对在恒定温度下测得的性状值进行非线性平均——通常用于推断在波动环境中的表现，但其准确性很少得到验证。我们在三种日温度范围（0、9和12°C）下，对一种传播疟疾的蚊子（斯氏按蚊）影响传播的三个性状——叮咬率、存活率、繁殖力进行了测量。我们将传播热适宜性模型与在恒定温度、波动温度下观察到的温度-性状关系，以及由速率总和预测的关系进行了比较。我们将结果绘制在斯氏按蚊的原生亚洲分布范围和入侵非洲分布范围上。我们发现：1）每日温度波动下的性状值与恒定温度实验和速率总和的结果都有很大差异；2）速率总和部分捕捉到了接近热最适点时性能的下降，但错误地预测了接近热极限时性能的增加；3）虽然恒定温度下的热适宜性不能完美地反映波动环境，但在估计和绘制热极限方面，它比速率总和更好。我们的研究为预测蚊媒疾病风险的方法提供了见解，并强调了加强对波动条件下生物体性能理解的必要性。
