Of the 121 reported cases of confirmed, unconfirmed and suspected Alabama Rot between December 2012 and April 2016 (at 8th May 2016), 92% were reported in Winter (52%, 63 cases) and Spring (40%, 48 cases). Only 8% (10 cases) were reported in Summer (4%, 5 cases) or Autumn (4%, 5 cases).
75 confirmed cases (confirmed by dog post mortem) were analysed in another post dated 8th May 2016 indicating that 89% cases were reported in Winter or Spring.
This post with 121 analysed cases seems to strengthen the argument for a Winter / Spring seasonality to Alabama Rot. This 121 case analysis has 46 more cases (+60%) than the 75 confirmed cases.
Chris Street of AlabamaRot.co.uk on 8th May 2016 analysed all confirmed UK Alabama Rot cases (between December 2012 and April 2016).
Data sources - Confirmed Cases UK map combined with Unconfirmed & Suspected cases (excludes confirmed cases) and cases-by-month spreadsheet.
Chart of All Alabama Rot cases by month between 2012 and 2016:
The monthly all cases were plotted by year:
The above chart shows the vast majority of Alabama Rot cases occur every year in Winter (December - February) and Spring (March - May).