Syndromic surveillance summary: 31 May 2026 week 22
Updated 4 June 2026
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Reporting week 22: 25 to 31 May 2026
During week 22 indicators for ‘heat exposure or sunstroke’ associated with the late-May warm weather peaked early in the week (around 26 May) and then declined as temperatures cooled with consistent patterns across all syndromic systems. Indicators for insect biting continued to remain elevated and above baseline. Rises in the ‘cellulitis’ indicator were also observed. Calls and online assessments for diarrhoea also increased and continue to be above seasonally expected levels.
Remote health advice syndromic surveillance system
During week 22, NHS 111 triaged calls and online assessments for ‘heat exposure or sunburn’ decreased following the sharp increase over the bank holiday weekend (23 to 25 May). Calls and online assessments for insect bites continued to increase, remaining above seasonally expected levels. Calls and online assessments for eye problems also increased, mainly in those aged 5 to 14 and 15 to 44 years, again above seasonally expected levels. Calls and online assessments for diarrhoea increased and continue to be above seasonally expected levels.
Please note that due to a technical issue the NHS 111 Online vomiting indicator has been temporarily removed from this bulletin.
Access the remote health advice syndromic surveillance bulletins
GP in-hours syndromic surveillance system
During week 22, GP consultations for ‘heat or sunstroke’ initially increased, peaking on Tuesday 26 May, and then decreasing in line with cooler weather towards the weekend. The increase was in line with an amber heat health alert in place across parts of England that continued into week 22. Consultations for insect bites increased and were above seasonally expected levels, while consultations for allergic rhinitis increased in line with expected levels. There was also an increase in consultations for cellulitis, particularly in adults aged 45 years and older.
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GP out-of-hours syndromic surveillance system
During week 22, GP out-of-hours daily contacts for ‘heat or sunstroke’ initially increased, peaking on Tuesday 26 May, and then decreasing in line with cooler weather towards the weekend. The increase was in line with an amber heat health alert in place across parts of England that continued into week 22. Contacts for insect bites continued to increase, however they remain close to seasonally expected levels.
Access the GP out-of-hours syndromic surveillance bulletins
Emergency department (ED) syndromic surveillance system
During week 22, ED attendances for ‘heat or sunstroke’ decreased after the sharp increase, which peaked on Tuesday 26 May due to the warm weather, but remain slightly above seasonally expected levels.
Access the emergency department syndromic surveillance bulletins
Ambulance syndromic surveillance system
During week 22, daily ambulance calls for ‘impact of heat or cold’ initially increased, peaking on Tuesday 26 May, and then decreasing in line with cooler weather towards the weekend.