Official Statistics

National flu report summary: 19 December 2019 (week 51)

Updated 1 October 2020

1. Main points: data up to week 50, 2019

Data up to week 50 (ending 15 December 2019) shows:

• during week 50, influenza activity has continued to increase for several indicators
• the impact of flu on healthcare services is at moderate intensity levels for hospitalisations and ICU/HDU influenza admissions
• the Department of Health and Social Care has issued an alert on the prescription of antiviral medicines by GPs
• there are signs that Respiratory Syncytial Virus (RSV) is starting to plateau but continues to circulate in the <5 year olds in England

The full weekly flu report this summary is based on, accompanying spreadsheet of data and slideset are available from weekly national flu reports: 2019 to 2020 season.

2. Surveillance scheme summaries

2.1 Community

Data from outbreak surveillance shows:

• there have been 155 new acute respiratory outbreaks reported in the past 7 days
• 86 outbreaks were reported from care homes where 46 tested positive for influenza A
• 7 outbreaks were reported from hospitals where 6 tested positive for influenza A
• 56 outbreaks were reported from schools where 30 tested positive for influenza A
• the remaining 6 outbreaks were reported from the Other settings category where two tested positive for influenza A

2.2 Primary care

Data from primary care surveillance shows:

• the rate of influenza-like illness (ILI) was above baseline threshold level
• the overall weekly ILI GP consultation rate was 16.0 per 100,000 in week 50 compared to 13.1 per 100,000 registered population in the previous week in participating GP practices for England
• in the devolved administrations, ILI rates were below baseline threshold levels for Scotland however at moderate impact levels in Northern Ireland and Wales

2.3 Secondary care

Data from secondary care surveillance shows:

• hospitalisation rate observed continues to be at moderate intensity levels, with a rate of 6.85 per 100,000 in week 50 compared to 5.13 per 100,000 trust catchment population in the previous week, for England (19 NHS Trusts)
• ICU and HDU admission rate observed was at moderate intensity levels, with a rate of 0.35 per 100,000 in week 50 compared to 0.23 per 100,000 trust catchment population in the previous week, for England (131 out of 143 NHS Trusts)
• there were two influenza confirmed admissions reported from the 6 severe respiratory failure centres in the UK

2.4 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 50
• in the devolved administrations, no statistically significant excess all-cause mortality for all ages was observed in Wales and Northern Ireland in week 50, and for Scotland in week 48 2019

2.5 Microbiological surveillance

Data from microbiological surveillance shows:

• in primary care, 94 samples tested positive for influenza (2 influenza A(H1N1)pdm09, 66 influenza A(H3) and 21 influenza A(not subtyped) and two co-infections of influenza A(not subtyped) and influenza B) through the UK GP sentinel swabbing schemes in week 50, with an overall positivity of 58.5%
• a total of 729 detections were recorded through the DataMart scheme (13 influenza A(H1N1)pdm09, 516 influenza A(H3), 191 influenza A(not subtyped) and 9 influenza B) with an overall positivity of 20.2% and above baseline threshold levels

2.6 Vaccination

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

• up to week 50 2019, in 79.4% of GP practices in England, the provisional proportion of people who had received the 2019 to 2020 influenza vaccine in targeted groups was 38.5% in under 65 years in a clinical risk group, 39.5% in pregnant women and 69.3% in those aged 65 and over
• up to week 50 2019, in 78.4% of GP practices reporting for the childhood collection the provisional proportion vaccinated was 32.5% in 2 year olds and 31.7% in 3 year olds

Provisional data from the second monthly collection of influenza vaccine uptake by frontline healthcare workers show 61.5% were vaccinated by 30 November 2019, compared to 61.0% vaccinated in the previous season by 30 November 2018.

Provisional data from the second monthly collection of influenza vaccine uptake for children of school years reception to year 6 shows 46.4% in school year reception age, 45.8% in school year 1 age, 45.0% in school year 2 age, 43.7% in school year 3 age, 43.2% in school year 4 age, 41.3% in school year 5 and 39.7% in school year 6 age were vaccinated by 30 November 2019.

3. International situation

• in the temperate zone of the northern hemisphere, influenza activity and respiratory illness indicators started to increase in most countries with influenza activity elevated across the countries in Western Asia
• in the temperate zones of the southern hemisphere, influenza activity returned to interseasonal levels
• worldwide, seasonal influenza A(H3N2) viruses accounted for the majority of detections.

4. 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.