Official Statistics

National flu report summary: 25 April 2019 (week 17)

Updated 26 September 2019

Main points: data up to week 16, 2019

Data up to week 16 (ending 21 April 2019) shows:

• during week 16, influenza continued to circulate in the community with activity indicators decreasing and below baseline
• the impact of flu on healthcare services is below baseline for hospitalisations and for ICU and HDU influenza admissions
• influenza A(H1N1)pdm09 and influenza A(H3N2) are co-circulating
• the Department of Health and Social Care has issued an alert on the prescription of antiviral medicines by GPs

The full weekly flu report this summary is based on, accompanying spreadsheet of data and slideset are available from weekly national flu reports: 2018 to 2019 season.

Surveillance scheme summaries

Community

Data from outbreak surveillance shows:

• there have been 23 new acute respiratory outbreaks reported in the past 7 days
• 21 outbreaks were reported from care homes where 3 tested positive for influenza A(not subtyped), 1 for influenza A(H3), 1 for picornavirus, 1 for parainfluenza and 2 for rhinovirus
• the remaining 2 outbreaks were reported from hospitals where 1 tested positive for influenza A(not subtyped) and 1 tested positive for influenza A(H3)

Primary care

Data from primary care surveillance shows:

• the rate of influenza-like illness (ILI) was below baseline threshold level
• the overall weekly ILI GP consultation rate was 3.4 per 100,000 registered population in participating GP practices for England, this is a slight decrease from 4.2 per 100,000 in week 14
• in the devolved administrations, ILI rates were below baseline threshold levels for Northern Ireland, Scotland and Wales

Secondary care

Data from secondary care surveillance shows:

• hospitalisation rate observed was below baseline impact levels, with a rate of 0.62 per 100,000 trust catchment population for England (17 NHS Trusts), this is a decrease from 0.71 per 100,000 in week 15
• ICU and HDU admission rate observed was below baseline impact levels, with a rate of 0.05 per 100,000 trust catchment population for England (135 out of 143 NHS Trusts), this is a slight decrease to the rate of 0.08 per 100,000 in week 15
• there were no new influenza admissions reported from the 6 severe respiratory failure centres in the UK

All-cause mortality

Data from all-cause mortality surveillance shows:

• no statistically significant excess all-cause mortality by week of death was seen overall and by age group in England in week 16
• in the devolved administrations, no statistically significant excess all-cause mortality for all ages was observed in Wales in week 16 2019 and in Scotland in week 14 2019; no data was available for Northern Ireland in week 16

Microbiological surveillance

Data from microbiological surveillance shows:

• in primary care 4 samples tested positive for influenza through the UK GP sentinel swabbing schemes in week 16
• in secondary care influenza percent positivity was 6.6%, below baseline threshold levels, this is similar to 7.3% in week 15
• a total of 137 detections were recorded through the DataMart scheme (3 influenza A(H1N1)pdm09, 84 influenza A(H3), 49 influenza A(unknown subtype) and 1 influenza B)

Vaccination

Data from the GP patient, healthcare worker and primary school-age children flu vaccine uptake programmes shows:

• provisional data from the fifth monthly collection of influenza vaccine uptake in GP patients shows that in 97.6% of GP practices the proportions of people in England who had received the 2018 to 2019 influenza vaccine in targeted groups by 28 February 2019 were: 48.0% in under 65 years in a clinical risk group, 45.2% in pregnant women and 72.0% in persons aged 65 years and over
• in 96.2% of GP practices reporting for the childhood collection the provisional proportions vaccinated by 28 February 2019 were: 43.8% in 2-year-olds and 45.9% in 3-year-olds
• provisional data from the fifth monthly collection of influenza vaccine uptake by frontline healthcare workers show 70.3% were vaccinated by 28 February 2019, compared to 68.7% vaccinated in the previous season by 28 February 2018
• provisional data from the fourth monthly collection of influenza vaccine uptake for children of school years reception to year 5 shows 63.9% in school year reception age, 63.4% in school year 1 age, 61.4% in school year 2 age, 60.2% in school year 3 age, 58.0% in school year 4 age and 56.2% in school year 5 age were vaccinated by 31 January 2019
• WHO have published their recommendations for the composition of the 2019 to 2020 Northern hemisphere influenza vaccine

International situation

• in the temperate zone of the Northern hemisphere, influenza activity continued to be reported with influenza A viruses predominating overall
• in the temperate zones of the Southern hemisphere, influenza activity remained at inter-seasonal levels, with the exception of some parts of Australia which remained above inter-seasonal levels
• worldwide, seasonal influenza subtype A viruses accounted for the majority of detections

Further information

See ‘seasonal influenza: guidance, data and analysis’ for further information on the symptoms, diagnosis, management, surveillance and epidemiology of seasonal influenza (flu).

See ‘sources of UK flu data: influenza surveillance in the UK’ for further information and guidance on the surveillance schemes we use to track seasonal influenza.