In a recent study published on the bioRxiv* preprint server, researchers retrospectively assessed the association between climate change and risks of disease spread caused by changes in bat distribution based on historical climate and bat occurrence data vampires during the previous century (1900-2020).
Study: Climate change has affected risk of spread of bat-borne pathogens. Image credit: Pablo Jacinto Yoder / Shutterstock
background
Bat-borne viruses have threatened global public health with increased morbidity and mortality among humans. Examples of bat-borne diseases include rabies, Ebola, severe acute respiratory syndrome coronavirus 1 (SARS-CoV-1) infections, and SARS-CoV-2 or coronavirus disease 2019 (COVID-19) infections. . Studies of the impacts of climate change on disease are scarce and have focused on vector-borne diseases based on future projections of climate change rather than retrospective empirical data, which could hinder progress in global preparedness against infectious diseases.
The species Desmodus rotundus (common vampire bat) is considered the key species of rabies transmission to other animal species (spillover) between Latin American regions. There is an ongoing debate about whether Desmodus rotundus (common vampire bat) will shift its range northward to warm and temperate areas at higher latitudes in the United States (US) in the future due to climate change.
About the study
In the present study, the researchers assessed the impacts of climate change on the spread risks of bat-borne pathogens based on climate and vampire bat distribution data from the previous century.
Rabies transmitted by Desmodus rotundus is a well-documented and understood model of disease transmitted directly to animals and humans in the tropical and subtropical Americas where rabies is commonly transmitted from Desmodus rotundus to livestock. Outbreaks of bat-borne rabies in livestock have increased over the past 40 years and indicate an increase in contagion events in the Americas. In addition, there is an ongoing debate about the possible distributional shift of D. rotundus northward into more temperate areas of the United States (US).
Thus, the team assessed changes in the distribution of Desmodus rotundus in response to climate change using ecological niche modeling and machine learning between 1901 and 2019. Data on the occurrence of D. rotundus in the previous century and data historical climates obtained from CRUTS (grid climate research unit). time series databases were used for the analysis).
Box plots of annual rabies outbreaks were prepared and percent change in cattle rabies outbreaks was assessed for Latin America. In addition, uncertainty maps were evaluated to identify areas of high uncertainty regarding potential regions of D. rotundus range expansion.
results
No statistically significant changes were found in the total region of the abundance and distribution of Desmodus rotundus during the mentioned period; however, the geographic distribution of D. rotundus was found to be shifting northward. The findings indicate that the common species of vampire bat has been moving steadily into the northern regions of Mexico at an annual average speed of eight km/year and could extend its range further into the continental US.
In addition, the team found some regions of uncertainty for the extent of Desmodus rotundus’ range, which included the highlands of the Andes Mountains and the temperate regions of the US. The study variable that most influenced the range shift of Desmodus rotundus was temperature variations, indicating that the abundance and distribution of D. rotundus and potential associated disease spillovers were related to the variations climatic
Conclusions
Overall, the study’s findings showed that climate change, particularly temperature variability, could affect the distribution of bats and the associated risk of bat-borne disease spills. The authors believe that the present study is the first of its kind to assess the impact of climate change on the distribution patterns and transmission risks of bat-borne disease pathogens.
Thus, they recommend that more research should be done on the association between climate change and bat-borne diseases and that the effects of climate variations on bat distribution should be incorporated into safety measures. The findings showed that climate variations had caused direct effects on the risks of rabies incidence by increasing virus reservoirs in temperate regions of the Americas, thereby increasing the risks of infection among humans, livestock and life wild
The study has provided evidence of bat range expansion driven by climate change, indicating that the emergence of infectious diseases and viral outbreaks will only increase in the future. Therefore, more research should be done to improve the understanding of climate change variations in bat distributions to prepare against possible cases of bat-borne pandemic in the coming times.
*Important news
bioRxiv publishes preliminary scientific reports that are not peer-reviewed and therefore should not be considered conclusive, guide clinical practice/health-related behavior, or be treated as established information.