Areas with water shortages experiencing mass mixed species congregations are particularly vulnerable to pathogen transmission between species, according to new research
A study published this month in "Science of the Total Environment" identifies water resources as a main vector for mammalian virus transmissions.
A team of scientists lead by the German Leibniz Institute for Zoo and Wildlife Research (Leibniz-IZW) tested their hypotheses by sampling surface water and sediments in waterholes in Tanzania, Namibia and Mongolia and screened the samples for equid herpesvirus (EHV). EHV’s are DNA viruses that are known to remain transmittable in water for weeks under laboratory conditions and are transmitted among species in Africa and Mongolia – which is why EHV’s were chosen as the model for the research paper.
Professor Alex Greenwood, lead researcher in the study, said: "We knew from our previous work, particularly with zebras in Africa, that equids become stressed when they are forced to aggregate in the dry season. When we looked at the effects of stress in captive zebras, we could see that it was associated with shedding of EHVs into the environment. This suggested that just at the time when animals are forced to congregate, they are most likely to be stressed and shed viruses. The stress is acting as a sort of signal to the virus to get into the water to infect more individuals.”
The paper concludes by suggesting that EHV’s are not the only viruses that remain stable and transmittable in water and therefore, monitoring and screening waterholes in water scarce environments could be a useful tool in identifying the emergence of diseases in wildlife.
The findings of this paper highlight the importance of prioritising future water security efforts in order to prevent future pandemics from occurring.
The COVID-19 pandemic provides a current example of how viruses can jump a host species to humans.