Zoonoses more sensitive to climate than solely human or animal pathogens
The university’s Institute of Infection and Global Health said findings will help policymakers prioritise surveillance for pathogens that may respond to climate change and contribute to strengthening resilience for infectious diseases.
They assessed the scale of climate change impact on a range of diseases that significantly affect human and animal health.
Climate-sensitive infectious diseases could change spatial distributions, annual/seasonal cycles or disease incidence and severity.
Dr Marie McIntyre said usually the effects of changes in climate are examined for specific, selected pathogens or diseases.
“Our work is different because we examined the climate sensitivity issue overall, in a more balanced way,” she told FoodQualityNews.
“We asked questions such as: will the majority of diseases respond to climate change or only a few; what are the characteristics of those diseases that will respond; and, is it possible that the most significant infectious diseases in health or economic terms could be resilient, so that the overall influence of changes in climate could be of relatively minor importance for infectious disease spread?”
Climate sensitivity of zoonotic pathogens
Diseases spread by insects and ticks (vector-borne diseases) were the most climate sensitive, followed by those transmitted in soil, water and food.
Zoonotic pathogens –that spread from animals to humans – were more climate sensitive than those that affect only humans or only animals.
Climate drivers
Primary: climate change, climate oscillations, extreme weather events, moisture, rainfall, temperature and wind
Secondary: altitude, vegetation, particulate matter and salinity
Moisture and rainfall were the most frequently occurring and most commonly linked drivers
As 75% of emerging diseases are zoonotic, such diseases may be impacted by climate change.
“Along with vector-borne and soil-borne, waterborne and foodborne pathogens were the most likely to have one or more climate drivers, and 39% of waterborne and nearly 31% of foodborne pathogens had three or more climate drivers,” said Dr McIntyre.
“Foodborne and waterborne pathogens were also significantly more likely to be zoonotic (transmitted from animals to humans), and zoonoses are more sensitive to climate than human-only or animal-only pathogens, so there are definite linkages of these two transmission routes to climate sensitivity.”
Nearly two-thirds of the pathogens examined were found to be sensitive to climate; and two-thirds of these have more than one climate driver.
Researchers said being sensitive to a broader range of climate variables likely means climate change is more likely to affect a disease or will affect it in more complex ways.
However, they stressed that response to climate change will depend on other drivers such as changes to travel and trade, land-use, deforestation, new control measures and development of antimicrobial resistance.
Effects between climate change and infectious disease
The team did a systematic review of published literature on 100 human and 100 domestic animal pathogens present in Europe that have the largest impact on health.
Dr McIntyre said it was not previously understood how big the effects will be between climate change and infectious disease and which diseases will be most affected.
“In previous work, another group had examined a number of diseases and their climate sensitivity using literature reviewing, and found that 49% were either directly or indirectly affected by climate change,” she said.
“By including many more pathogens which have a high impact upon health, (many of which we might assume to be less likely to be influenced by climate), we might have expected to have found less climate sensitivity in our study; we actually found more, with 63% of the pathogens examined being sensitive to climate drivers.”
Dr McIntyre added the study provides a framework on which to focus the next stage of research, which should look at the nature of associations between pathogens/disease and climate drivers.
It received funding from the Natural Environment Research Council and principal investigator, Professor Matthew Baylis, had funding from The Leverhulme Trust.
Source: Scientific Reports
“Systematic Assessment of the Climate Sensitivity of Important Human and Domestic Animals Pathogens in Europe”
Authors: K. Marie McIntyre, Christian Setzkorn, Philip J. Hepworth, Serge Morand, Andrew P. Morseand Matthew Baylis
