Scientists have genetically-modified a mouse so that it can catch a cold. Previously the only mammals that could catch colds were higher primates like man. It’s thought that this development will lead to potential new treatments for colds because these mice will enable more testing to be done. (http://news.bbc.co.uk/1/hi/health/7225742.stm)
So why did this news send a chill down my spine?
I remember watching a documentary last year about the last great flu epidemic, the Spanish flu of 1918, that killed 40-50 million worldwide. Research done recently revealed that this flu was a variant of the bird flu, H5N1.
Now, how could bird flu have spread to humans? Surely by virtue of its name and type, bird flu is supposed to have been confined to one species – birds.
However, it seemed that may have been another vector involved, pigs. Pigs are susceptible to both bird and human viruses. At that time World War I was being fought and huge armies were quartered near livestock. It was possible that pigs caught the bird flu and they acted as “mixing vessels”, causing the virus to mutate sufficiently so that humans could catch it. (http://news.nationalgeographic.com/news/2005/10/1005_051005_bird_flu.html
So, is it too much of a leap of fantasy to substitute “mice” for “pigs”? Surely by increasing the susceptibility of mice to human viruses, the possibility is open for mice-type viruses to be modified within these mice to be contagious to humans? What precautions are these scientists taking to make sure that diseases, once unique to smaller mammals, won’t leap the species-barrier from rodents to humans?
It’s harder to shut Pandora’s Box now that we’ve opened it.