The next 24 hours will be critical for scientists in Germany who are trying to understand if an outbreak of infections from a deadly strain of E. coli currently sweeping the country is a severe instance of a normal infection, or something different.
Three women have died today from suspected infections with the bacteria enterohaemorrhagic Escherichia coli (EHEC) which causes dysentery-like, bloody diarrhoea, severe cramping and fever. Health authorities have registered a further 400 confirmed cases – mostly young women. First cases emerged barely two weeks ago and authorities have been shocked at the rate at which this outbreak has spread.
At least a hundred patients are being treated in hospital. The Robert Koch Institute, the national institute responsible for disease control, confirmed this morning that 80 patients with EHEC infection had gone on to develop the life-threatening haemolytic uraemic syndrome (HUS), which can lead to acute kidney failure.
Today’s deaths were of two women in their 80s – one of these has already been confirmed as an EHEC case – and one young woman.
Normally just a thousand or so cases of EHEC are reported in Germany over the course of a year, and these happen mostly in children. So health authorities are perplexed that this time most victims have so far been young adult women, not a group typically prone to infection.
Early cases were confined to northern Germany, but this afternoon, the first suspected cases have been reported in the southern German state of Bavaria.
Martin Aepfelbacher at the Hamburg-Eppendorf University Clinic says the patient specimens that have come into his clinic are revealing E. coli strains that haven’t been seen in outbreaks in Germany in the past. The normal EHEC strain is called 0157:H7, but antibodies to this strain, which scientists usually use to diagnose the infection, are not reacting with the patient samples. The bacterial strains currently infecting patients also show different biology to known EHEC strains.
According to Aepfelbacher, these different strains are also showing up in other clinics around the country. “This is not a cause for concern at the moment” says Aepfelbacher, adding that treatment for patients is not dependent on the bacterial strain. “But further analysis of these unusual strains – like deep sequencing – might tell us more about their pathogenicity, and maybe give us clues as to why this outbreak is behaving differently”.
EHEC strains of E. coli are endemic in cattle and typically passed to humans through contaminated foods such as undercooked meat or raw milk products. The German authorities are frantically searching for the source of this outbreak. They currently think people may have the contracted the infection from fruit or vegetables from fields fertilized with manure. This may explain the predominance of cases in young women – those buying, and handling, the foods.
Interesting that it appears to be yet another non-O157:H7 outbreak (recall Japan’s E. coli O111 outbreak a month ago that sickened nearly 100 and killed at least 4). Hello, U.S. Government – do you think it is time to list these non-O157’s that cause human illness as adulterants?