Some ants can help researchers track down viruses and understand how they circulate. An international team of scientists has just obtained the proof.
Using animals as sentinels is nothing new. We knew the canary in the mine, which used to warn of the presence of toxic gases, or the use of certain shells such as mussels to filter and monitor certain marine pollution, but here the experience is completely new, and opens up fascinating perspectives. . Because an international team involving French scientists from several research institutes, the Center for International Cooperation in Agricultural Research for Development (Cirad), l‘Research Institute for Development (IRD) and theNational Research Institute for Agriculture, Food and the Environment (Inrae), had the original idea of using army ants as a virus monitoring agent in tropical forests.
These 1 cm long legionary ants, equipped with large mandibles, are very voracious, they lead a kind of collective raids to feed, raids during which a colony of 500,000 ants can devour 2 kg of food that is in its path. : plants, other insects, remains of animal carcasses, etc. By doing this, they can also swallow a very wide variety of viruses. The researchers therefore thought that by analyzing the contents of their digestive system, and even more finely, by analyzing all the genetic material carried by the ants, they could have an idea of the plant and animal viruses existing in the forest. . Indeed, the idea was good.
Detect risks of disease transmission to humans
The researchers did indeed find viruses in the bodies of the ants. They specifically found genetic sequences of viruses. Only out of 209 ants analyzed, 157 different viral genera could be found. “So many viruses on such a small amount of ants that are all in one place, it’s huge, it’s incredible diversity” explains Philippe Roumagnac, virologist at CIRAD, who carried out this work with Eric Leroy, “This represents 6% of all viral genera known to date in the new world” he adds. This means that ants “rake” viruses extremely broadly and efficiently. This discovery is very promising, because one could imagine that by setting up a system of regular collection of army ants in different places, one could have an idea of the viruses which circulate locally in plants and animals. This would perhaps make it possible to detect their presence and the possible risks of disease transmission to human populations or plants.
Researchers monitor viruses in tropical forests because of the pathogenic viruses that have caused epidemics in humans, more than 60% are of animal origin and also because over the past 50 years , almost all of the serious infectious diseases that have emerged originally came from the forests of Africa, Asia or America.