A severe disease of horses may be the next new infection to hit Britain after the Schmallenberg virus causing birth defects in sheep and cattle on English farms, scientists are reporting.
New fears about horse diseases
Fears are growing that African horse sickness, which kills 95 per cent of infected animals, may be brought to Britain by wind-borne insects, just as the Schmallenberg virus was last year, and the Bluetongue virus before that.
Scientists are concerned that African horse sickness, which kills 95 per cent of infected animals, may be brought to Britain by wind-borne insects, just as the Schmallenberg virus was last year, and the Bluetongue virus before that in 2007.
Until these two pathogens arrived in Britain, carried by biting midges blown on the wind from continental Europe, Britain had been free of midge-borne diseases. But scientists are warning that they may be only the first of a considerable number of new infections, including some affecting humans, which are being helped to spread north through Europe by the warming climate.
The danger was spelled out at an expert briefing in London on the progress of the Schmallenberg infection, which is affecting 83 farms in southern England, five of them cattle farms and the rest sheep farms. The disease, which appears to have no effect on humans, makes livestock ill for a few days, after which they recover and are subsequently immune â but if it is caught by pregnant animals, it can severely deform or kill their foetuses.
Professor Peter Mertens, research leader for vector-borne viral diseases at the Institute for Animal Health and his colleague Professor Matthew Baylis, Professor of Veterinary Epidemiology at the University of Liverpool, are concerned at even more severe pathogens which might be brought to the British Isles by insects carried by the wind, including West Nile virus, which affects animals, birds and people.
"Until the 1990s we did not have midge-borne viruses in northern Europe," Professor Baylis said, "They were confined to the far south-west and the far south-east of the continent â to Spain and some of the Greek islands. But in 1998 Bluetongue virus began to spread north, and it has never gone away."
Research had shown that Europe's warming climate was making the spread more possible.
The possible arrival of African horse sickness was "the main worry," Professor Baylis said. There is a vaccine for it, but it is a live-virus vaccine which carried its own risks, he said,