Slaughter of the lambs

Most of the infectious diseases to infect humans are zoonotic or animal diseases, long present in the environment, often circulating for hundreds even thousands of years among their primary animal hosts, and only rarely making the jump to infect humans. The influenza virus perhaps provides the best example of this.

The virus is nurtured among wild bird colonies in parts of Asia and has circulated among its primary host for hundreds of years every so often reaching out to infect human populations.

Schmallenberg virus demonstrates once again just how closely the natural environment and animal health influences our everyday lives and just how vulnerable our health and food security are to threats from the microbial world. While the full impact of Schmallenberg virus is still playing out in parts of Western Europe, will our geographic isolation, vigilance and surveillance offer a defence should the virus move from the Northern Hemisphere, or is it just a matter of time before we see it ‘downunder’? Are we facing a ticking time-bomb for a country with millions of sheep and export earnings in the billions of dollars?

Quite probably this virus may burn itself out among the farms of Western Europe over the next few months particularly as the new vaccine becomes widely available, although as temperatures warm, and midge populations multiply, the threat may actually intensify.

It also seems something of an irony that in health terms we always seem to have to react after the threat has been identified rather than anticipate it before it actually occurs, and by the time we have identified the threat and managed to construct a response, thousands, perhaps millions of people and animals have already suffered.

As for us in Australia, if  it’s not Schmallenberg virus, then we can rest assured that somewhere in the world a new viral threat already lurks, perhaps circulating among its natural animal hosts just waiting for the opportunity to jump to another species, mutate, and threaten our complacency.

It’s a brave but perilous world that confronts us.