Official Statistics

National flu report summary: 31 January 2019 (week 5)

Updated 26 September 2019

Main points: data up to week 4, 2019

Data up to week 4 (ending 27 January 2019) shows:

• during week 4, influenza continued to circulate in the community, with activity indicators at low intensity and early signs of peaking
• the impact of flu on healthcare services is at medium impact for hospitalisations, and ICU and HDU influenza admissions
• influenza A(H1N1)pdm09 is the dominant circulating subtype
• 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 87 new acute respiratory outbreaks reported in the past 7 days
• 49 outbreaks were reported from care homes where 13 tested positive for influenza A(not subtyped), 2 for rhinovirus and 3 for RSV
• 10 outbreaks were reported from hospitals where 2 tested positive for influenza A(not subtyped) and 3 for influenza A(H1N1)pdm09
• 23 outbreaks were reported from schools where 1 was positive for influenza A(not subtyped)
• the remaining 6 outbreaks were reported from the other settings category where 1 was positive for influenza A(H1N1)pdm09 and 1 for influenza A(not subtyped)

Primary care

Data from primary care surveillance shows:

• the rate of influenza-like illness (ILI) was at low intensity levels
• the overall weekly ILI GP consultation rate was 17.5 per 100,000 registered population in participating GP practices for England, this is a decrease from 19.6 per 100,000 in week 3
• in the devolved administrations, ILI rates were at below baseline threshold levels for Scotland and Northern Ireland and were at low intensity levels for Wales

Secondary care

Data from secondary care surveillance shows:

• hospitalisation rate observed was at medium impact levels, with a rate of 6.11 per 100,000 trust catchment population for England (21 NHS Trusts), this is an increase from 5.12 per 100,000 in week 3
• ICU and HDU admission rate observed was at high impact levels, with a rate of 0.56 per 100,000 trust catchment population for England (135 out of 143 NHS Trusts), this is similar to 0.57 per 100,000 in week 3
• there were 8 new influenza admissions (6 influenza A(H1N1)pdm09 and 2 influenza A(unknown subtype)) 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 4
• in the devolved administrations, no statistically significant excess all-cause mortality for all ages was observed in Northern Ireland and Wales in week 4 2019; statistically significant excess all-cause mortality was observed in Scotland in week 2 2019

Microbiological surveillance

Data from microbiological surveillance shows:

• in primary care 27 samples tested positive for influenza (16 influenza A(H1N1)pdm09, 6 influenza A(H3) and 5 influenza A(not subtyped)), with a positivity of 45.0% through the UK GP sentinel swabbing schemes
• in secondary care influenza percent positivity was 24.9%, above baseline threshold levels, this is an increase from 21.1% in week 3
• a total of 603 detections were recorded through the DataMart scheme (341 influenza A(H1N1)pdm09, 107 influenza A(H3), 154 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:

• up to week 4 2018, in 97.4% of GP practices in England, the provisional proportion of people who had received the 2018 to 2019 influenza vaccine in targeted groups was 46.7% in under 65 years in a clinical risk group, 44.8% in pregnant women and 71.2% in those aged 65 years and over
• in 97.5% of GP practices reporting for the childhood collection the provisional proportion vaccinated was: 43.0% in 2-year-olds and 45.0% in 3-year-olds
• provisional data from the third monthly collection of influenza vaccine uptake by frontline healthcare workers show 65.8% were vaccinated by 31 December 2018, compared to 63.9% vaccinated in the previous season by 31 December 2017
• provisional data from the third monthly collection of influenza vaccine uptake for children of school years reception to year 5 shows 62.6% in school year reception age, 62.2% in school year 1 age, 60.3% in school year 2 age, 59.1% in school year 3 age, 56.9% in school year 4 age and 55.1% in school year 5 age were vaccinated by 31 December 2018

International situation

• in the temperate zone of the Northern hemisphere, influenza activity continued to increase slowly
• in the temperate zone of the Southern hemisphere, influenza activity returned to inter-seasonal levels with exception of some parts of Australia
• 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.