April 10th, 2018
Scientists from Trinity College Dublin (TCD) have developed a method to predict the effect of climate change on infectious diseases.
According to the scientists, the method can identify which infectious diseases will have worsened or diminished effects with increasing temperatures.
The method, details of which are published in the journal PLOS Biology, can be applied widely to several host-pathogen combinations and warming scenarios.
Traditionally, scientists have found it difficult to pinpoint the exact impact of higher temperatures on diseases as temperatures can affect hosts and pathogens in multiple ways.
To predict the severity of diseases, scientists also require data on the temperature sensitivity of all the processes involved, which is not always available.
The solution found to the problem by TCD scientists was the metabolic theory of ecology, which was tested using the water flea and its pathogen as a model system.
This theory is based on the idea that every biological process is controlled by enzymes, and that the activity and temperature dependence of those enzymes can be represented through simple equations.
The theory allows scientists to predict the host and pathogen dependence over temperature, even with limited data.
The study measured changes regarding processes such as host mortality, aging, parasite growth and damage of the water flea and its pathogen over different temperatures.
The results showed that each process had a unique relationship with temperature variations. According to the report, while damage caused to the host per pathogen appeared to be independent of temperature, rates for both host mortality and pathogen growth were very dependent, though in opposite ways.
“Until now, no study has shown if this works for simple – unicellular – pathogens growing within their host, but we have been able to show that the method works very well in the model system we used,” said one of the lead authors of the research, Professor Pepin Luijckx.
“What is exciting is that these results demonstrate that linking and integrating metabolic theory within a mathematical model of host-pathogen interactions is effective in describing how and why disease interactions change with global warming,” said Professor Luijckx.
“Due to its simplicity and generality, the method we have developed could be widely applied to understand the likely impact of global warming on a variety of diseases.”
Climate Change and Communicable Diseases
Climate change can cause shifts in the transmission ranges of many vector-borne diseases such as West Nile virus, malaria, and dengue.
Hotter summers, warmer winters and increased rainfall caused as a result of global warming may lead to a change of habitat for disease-carrying organisms such as such as ticks and mosquitoes.
Climate change can also influence water quality and availability, and also lead to increased risks of flooding in some regions. This can have effects on water-borne diseases such as dysentery and cholera.