The Berlin AP is reporting today that German authorities have once again revised the numbers of people affected by the huge E. coli O104:H4 outbreak striking the country.  Currently at least 1,534 people have been confirmed infected by the deadly pathogen, with 17 deaths and 470 suffering from hemolytic uremic syndrome (HUS).

Medical authorities appeared no closer to discovering either the source of the infection or the mystery at the heart of the outbreak: why the unusual strain of the E. coli bacteria appears to be causing so many cases of hemolytic uremic syndrome, which attacks the kidneys and can cause seizures, strokes and comas.

Typically, about 10 percent of people who become infected with Shiga toxin-producing E. coli, like the E. coli O104:H4 strain identified in the Germany outbreak, develop HUS.  The number of HUS victims thus far identified in this outbreak, however, is far above the norm.

That discrepancy could indicate that a vast number of cases haven’t been reported because their symptoms are relatively mild, medical experts said.

But they also offered another, more disturbing theory — the strain of EHEC causing the outbreak in Europe could be more dangerous than any previously seen.

“There may well be a great number of asymptomatic cases out there that we’re missing. This could be a much bigger outbreak than we realize right now,” said Paul Hunter, a professor of health protection at the University of East Anglia in England. “There might also be something genetically different about this particular strain of E. coli that makes it more virulent.”