Several major outbreaks, including Ebola, SARS and, it seems, HIV have come about because people have become infected with a virus that originally was associated with an animal. What has taken place is a species jump.
How bad the infection is in the news species is variable. One thing that seems to increase the virulence is how closely related the different species are to each other. At least, this is the result of studies on fruit flies and from this a generalized statement has been made.
In a new study, scientists infected 48 species of fruit fly with an RNA virus. They discovered that the harm causes by the virus varied, with some species of fruit fly relatively resistant and others dying quite rapidly.
Those that died were species more closely related to the species that was the original source of the virus. These flies had a greater “viral load.”
Fruit flies are frequently used in research that has a genetic element. One reason is because this speed up experiments. The flies have a short lifespan, so it is possible to evolve many generations of fruit flies in a relatively short time period and to review test data fairly rapidly.
While the research was carried out on fruit flies, the research team also reference a different study that was carried out on frogs, where different types of the amphibians were infected with the chytrid fungus.
How far this research can be taken is a matter of conjecture. However, the researchers are aiming to extend the other further and look at other closely related species.
The findings have been published in the journal PLOS Pathogens. The research is titled “The Causes and Consequences of Changes in Virulence following Pathogen Host Shifts.”
