Abstract
We used Campylobacter data collected by UK Health Security Agency (UKHSA, formerly Public Health England) through national surveillance in England and Wales between 1 January 1989 and 14 April 2010 (Secondary Generation Surveillance System database). The 994,791 reported cases were linked to local weather parameters provided by the Met Office statistically interpolated to the locations of diagnostic laboratories via the MEDMI platform (Fleming LE, et al. doi:10.3390/ijerph110201725). Weather variables were available for the same period. Known travel-related cases were excluded from the analysis. The linkage was conducted on laboratory address because this was more complete than the patient residential address and the discrepancies between some weather variables (temperature and rainfall) between the laboratory and the corresponding patient location are known to be small (Nichols GL, et al. doi:10.1136/bmjopen-2012-001179; Djennad A et al doi:10.1186/s12879-018-3106-9). Daily variables available for the same time period for England and Wales included: maximum and minimum air temperature, rainfall, relative humidity and mean wind speed. Data were extracted for the date when specimen reached any of the 416 UKHSA diagnostic laboratories in England and Wales (although the data shows that only 213 laboratories were used for diagnostic) and for at least any previous 365 days; day-length was calculated from the day of the year, and the latitude of the laboratories.