Devastating coral disease caused by faecal bacteria

From a story by Gaia Vince on the NewScientist.com news service:

A disease that is devastating Caribbean coral reefs is caused by a bacterium commonly found in the human gut, US researchers have discovered.

White pox, one of the fastest spreading coral diseases, targets elkhorn coral, destroying tissue at a rate of between 2 and 10 cm2 per day, at each lesion. Reefs in the Florida Keys have lost about 85 per cent of their elkhorn coral to the disease. On some Caribbean reefs, the figure is as high as 98 per cent.

Scientists at the University of Georgia, Athens, US, analysed infected coral and identified a common faecal enterobacterium, Serratia marcescens, as the cause of white pox.

"When we started the research, I initially thought I was going to discover a new species of obscure marine pathogen. What we found was one of the commonest bacteria known to man," James Porter, professor of ecology at the University of Georgia, told New Scientist.

"Serratia marcescens is a bacterium found in the intestines of humans and other animals as well as soil and water. This is the first time that a common member of human gut flora has been shown to be a marine invertebrate pathogen. We haven't proved the source of the infection yet, but I suspect it is due to water polluted with human faeces," he says.