Climate factors driven typhus group rickettsiosis incidence dynamics in Xishuangbanna Dai autonomous prefecture of Yunnan province in China, 2005–2017

Abstract

Background: Typhus group rickettsiosis (TGR), which is a neglected vector-borne infectious disease, including epidemic typhus and endemic typhus. We explored the lag effects and nonlinear association between meteorological factors and TGR incidence in Xishuangbanna Dai autonomous prefecture from 2005 to 2017, China. Methods: A Poisson regression with a distributed lag nonlinear model (DLNM) was utilized to analyze TGR cases data and the contemporaneous meteorological data. Results: A J-shaped nonlinear association between weekly mean temperature and TGR incidence was found. The cumulative exposure to weekly mean temperature indicated that the RR increased with the increment of temperature. Taking the median value as the reference, lower temperatures could decrease the risk of TGR incidence, while higher temperatures could increase the risk of TGR incidence and last for 21 weeks. We also found a reversed U-shaped nonlinear association between weekly mean precipitation and TGR incidence. Precipitation between 5 mm and 13 mm could increase the risk of TGR incidence. Taking the median value as the reference, no precipitation and lower precipitation could decrease the risk of TGR incidence, while higher precipitation could increase the risk of TGR incidence and last for 18 weeks. Conclusions: The prevention and control measures of TGR should be implemented according to climatic conditions by the local government and health departments in order to improve the efficiency.

Climate Change and Vector-Borne Diseases in China: A Review of Evidence and Implications for Risk Management

“…Generally, temperature plays an important role in the number of reported insect-borne and rodent-borne diseases cases [42,[53][54][55][56]. However, typhus group rickettsiosis was negatively related to average temperature, average ground temperature, and extreme minimum temperature [13]. The same negative correlation was also found between temperature and schistosomiasis [47].…”

“…The relationship between climate factors and vector-borne diseases was non-linear; a J-shape or reverse U-shape was always found between them, which means, respectively, that the risks increased continuously or increased and then decreased with the rise of certain meteorological factors. Temperature, precipitation, and humidity were the main parameters contributing to the transmission of vector-borne diseases [13,[50][51][52]. Generally, temperature plays an important role in the number of reported insect-borne and rodent-borne diseases cases [42,[53][54][55][56].…”

“…China is one of the most vulnerable countries with respect to climate change [11]. Many studies have found the significant positive relationship between weather conditions and vector-borne diseases in China, including the effects of meteorological factors, such as temperature, precipitation, humidity, wind speed [12][13][14][15][16][17], and extreme weather events (e.g., extremely high temperatures, extremely high rainfall, and tropical cyclones) [18][19][20][21][22][23][24]. The 2020 China Report of the Lancet Countdown on Health and Climate Change showed that China's climate suitability for mosquito-borne dengue fever has increased by 37% in the past half century [25].…”

Newly Discovered Male of Heteropoda Languida Simon, 1887 (Araneae: Sparassidae) in Yunnan, China

“…Xishuangbanna Dai autonomous prefecture (latitude 21°10′N-22°40′N, longitude 99°55′E-101°50′E) located in the southwestern part of China (Fig. 5), bordering Myanmar to the southwest and Laos to the southeast, with mild, warm and humid climate all year round with an annual average temperature from 18.6 to 22.9 °C, and an annual precipitation from 1347.4 to 1916.8 mm (Gao et al, 2020). Therefore, it is rich in animals and plants, belonging to Indo-Burma biodiversity hotspot (Liu et al, 2010;Myers, 1988).…”

Six Heteropoda Spiders (Araneae: Sparassidae) from Xishuangbanna Dai Autonomous Prefecture, China

“…It is reported that the Xishuangbanna Dai autonomous prefecture is a mild, humid, and warm all year around. The annual average temperature is recorded from 18.6 to 22.9°C, while the annually precipitation was recorded from 1347.4 to 1916.8 mm (Gao et al, 2020). In order to understand the biodiversity of Heteropoda spiders in China and to study their dispersal route at China and global level, our colleagues of Hubei University conducted a series of surveys on huntsman spiders and yielded several Heteropoda species in Dai Autonomous Prefecture of Xishuangbanna during the last ten years.…”