Official Statistics

National flu report summary: 28 December 2018 (week 52)

Updated 26 September 2019

Main points: data up to week 51, 2018

Data up to week 51 (ending 23 December 2018) shows:

• influenza activity continues to increase, with evidence now that influenza is starting to circulate in the community with indicators approaching baseline threshold levels
• the impact of flu on healthcare services is at moderate intensity levels for hospitalisations and ICU/HDU admissions.
• Influenza A(H1N1)pdm09 is the dominant subtype

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

Thirty-six new acute respiratory outbreaks have been reported in the past 7 days. Thirty-one outbreaks were reported from care homes where 8 tested positive for influenza A(not subtyped) and 1 was positive for RSV. Four outbreaks were reported from hospitals where 2 tested positive for influenza A(not subtyped). The remaining outbreak was reported from a school with no test result available.

Primary care

Data from primary care surveillance shows:

• the rate of influenza-like illness (ILI) was below baseline threshold levels
• the overall weekly ILI GP consultation rate was 9.4 per 100,000 registered population in participating GP practices for England, this is an increase from 8.1 per 100,000 in week 50
• in the devolved administrations, ILI rates were also below baseline threshold levels

Secondary care

Data from secondary care surveillance shows:

• hospitalisation rate observed was at moderate impact threshold levels, with a rate of 1.30 per 100,000 trust catchment population for England (16 NHS trusts), this is an increase from 0.82 per 100,000 in week 50
• ICU and HDU admission rate observed was at moderate impact threshold levels, with a rate of 0.19 per 100,000 trust catchment population for England (115 out of 143 NHS Trusts), this is an increase from 0.11 per 100,000 in week 50
• there were 4 new influenza admissions (4 influenza A(H1N1)pdm09) 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 50
• in the devolved administrations, no statistically significant excess all-cause mortality for all ages was observed in Scotland in week 51 and in Northern Ireland and Wales in week 50

Microbiological surveillance

Data from microbiological surveillance shows:

• in primary care 8 samples tested positive for influenza (5 influenza A(H1N1)pdm09, 1 influenza A(h3N2) and 2 influenza A(unknown subtype)) with a positivity of 119.% through the UK GP sentinel schemes, an increase from 12.9 in week 50
• in secondary care influenza percent positivity was 11.8%, above baseline threshold levels, this is an increase from 11.0% in week 49
• a total of 215 detections were recorded through the DataMart scheme (89 influenza A(H1N1)pdm09, 35 influenza A(H3), 89 influenza A(unknown subtype) and 2 influenza B)
• RSV positivity decreased to 12.0%

Vaccination

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

• up to week 50 2018, in 96.7% of GP practices in England, the provisional proportion of people who had received the 2018 to 2019 influenza vaccine in targeted groups was 43.4% in under-65s in a clinical risk group, 42.8% in pregnant women and 68.6% in people aged 65 years and over
• in 97.1% of GP practices reporting for the childhood collection the provisional proportion vaccinated was: 40.5% in 2-year-olds and 41.7% in 3-year-olds
• provisional data from the second monthly collection of influenza vaccine uptake by frontline healthcare workers show 61.0% were vaccinated by 30 November 2018, compared to 59.3% vaccinated in the previous season by 30 November 2017
• provisional data from the second monthly collection of influenza vaccine uptake for children of school years reception to year 5 shows 49.6% in school year reception age, 49.4% in school year 1 age, 47.7% in school year 2 age, 46.8% in school year 3 age, 45.2% in school year 4 age and 43.7% in school year 5 age were vaccinated by 30 November 2018

International situation

• in the temperate zone of the Northern hemisphere, influenza activity started to increase although overall influenza activity remained low; increased influenza was reported in some countries of Southern and South-East Asia
• in the temperate zone of the Southern hemisphere, influenza activity returned to inter-seasonal levels
• worldwide, seasonal influenza subtype A viruses accounted for the majority of detections

Further information

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.

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.