This E. coli O157:H7 outbreak is shaping up to be another large leafy green disaster.

One piece of good news is that the illnesses began July 26 and the last reported case became ill on August 8. That means that the case numbers in the pipeline are likely all that there are – whatever that number is right now.

The CDC reported today that the number of people infected with the outbreak strain of E. coli O157:H7 has reached 37, from four states: Indiana (1), Michigan (15), Ohio (19), and Pennsylvania (2). Nine people have been hospitalized, including three in Michigan who have a type of kidney failure called hemolytic uremic syndrome. No deaths have been reported.

However, Michigan has reported 108 cases of E. coli, with 43 of them confirmed to be E. coli O157:H7, the strain being investigated in the outbreak in Michigan, Ohio, Pennsylvania and Indiana.  The illness onset dates range from late July through early August. Outbreak cases have been reported from 18 jurisdictions including the counties of Allegan, Branch, Clinton, Genesee, Gratiot, Jackson, Kent, Macomb, Midland, Monroe, Muskegon, Oakland, Ogemaw, Ottawa, Saginaw, Washtenaw, and Wayne and the City of Detroit. The age range of those affected are 6 to 94 years old. Among the Michigan outbreak cases with available information to date, 56% have been hospitalized. Four cases of hemolytic uremic syndrome (HUS), a severe complication that occurs in some people diagnosed with STEC infection, have been identified.

The Ohio Department of Health has reported nineteen cases of E. coli O157:H7 in Clermont County (1), Cuyahoga County (2), Franklin County (1), Lorain County (3), Lucas County (2), Mahoning County (2), Summit County (1), and Wood County (7).  However, Wood County itself reports 22 sick with 7 hospitalized.

The numerical confusion is likely due to reporting confirmed (by WGS) vs probable cases (Not WGS results back yet). It is also likely due to delay in reporting between counties, states and the CDC.