These codes are not intended to be mandatory, but are to be used as a starting point for the identification of influenza infection in routine Electronic Health Record (EHR). Each study may differ in the sensitivity and specificity of the coding required.
According to the National Health Service (NHS), Influenza is a common infectious viral illness spread by coughs and sneezes. Some of the main symptoms of influenza include: high temperature (fever) of 38C or above, tiredness and weakness, headache, general aches and pains and dry or chesty cough. Cold-like symptoms, such as a blocked or runny nose, sneezing, and a sore throat, can also be caused by influenza, but they tend to be less severe than the other symptoms.
https://www.nhsinform.scot/illnesses-and-conditions/infections-and-poisoning/flu
According to the National Institute for Health and Care Excellence (NICE) guidelines, Influenza is an acute respiratory illness caused by RNA viruses f the family Orthomyxoviridae (influenza viruses). There are three types of influenza virus: Influenza A occurs more frequently and is more virulent. It is responsible for local outbreaks, larger epidemics and pandemics. Influenza B often co-circulates with influenza A during the yearly outbreaks. Generally, influenza B causes less severe clinical illness, although it can still be responsible for outbreaks. Influenza C usually causes a mild or asymptomatic infection similar to the common cold.
Influenza presents with symptoms appearing around 2 days after exposure. Uncomplicated influenza signs and symptoms include: coryza, nasal discharge, cough, fever, gastrointestinal symptoms, headache, malaise, myalgia, arthralgia, ocular symptoms, and sore throat. Complicated influenza is defined by signs and symptoms that: require hospital admission, involve the lower respiratory tract, central nervous system, or cause significant exacerbation of an underlying medical condition.
https://cks.nice.org.uk/topics/influenza-seasonal/
Not found code search
Publications in 2020-2021 identified in PubMed
Moss JWE, Davidson C, Mattock R, Gibbons I, Mealing S, Carroll S. Quantifying the direct secondary health care cost of seasonal influenza in England. BMC Public Health. 2020 Sep 29;20(1):1464. doi: 10.1186/s12889-020-09553-0. PMID: 32993588; PMCID: PMC7526100.
Ramsay J, Minton J, Fischbacher C, Fenton L, Kaye-Bardgett M, Wyper GMA, Richardson E, McCartney G. How have changes in death by cause and age group contributed to the recent stalling of life expectancy gains in Scotland? Comparative decomposition analysis of mortality data, 2000-2002 to 2015-2017. BMJ Open. 2020 Oct 7;10(10):e036529. doi: 10.1136/bmjopen-2019-036529. PMID: 33033012; PMCID: PMC7542937.
Wabe N, Li L, Lindeman R, Post JJ, Dahm MR, Li J, Westbrook JI, Georgiou A. Evaluation of the accuracy of diagnostic coding for influenza compared to laboratory results: the availability of test results before hospital discharge facilitates improved coding accuracy. BMC Med Inform Decis Mak. 2021 May 22;21(1):168. doi: 10.1186/s12911-021-01531-9. PMID: 34022851; PMCID: PMC8141245.
Fitzpatrick T, Malcolm W, McMenamin J, Reynolds A, Guttmann A, Hardelid P. Community-Based Antibiotic Prescribing Attributable to Respiratory Syncytial Virus and Other Common Respiratory Viruses in Young Children: A Population-Based Time-series Study of Scottish Children. Clin Infect Dis. 2021 Jun 15;72(12):2144-2153. doi: 10.1093/cid/ciaa403. PMID: 32270199.
Code repositories
ID- 1 - Repository- Manchester Clinical Codes - Description- Trends in antibiotic prescribing in primary care for clinical syndromes subject to national recommendations to reduce antibiotic resistance, UK 1995-2011: analysis of a large database of primary care consultations - Conditions- URTI - Publication- https://doi.org/10.1093/jac/dku291 - Clinical codes- Read Version 2
ID- 2 - Repository- HDR UK National Phenomics Resource Project - Description- A chronological map of 308 physical and mental health conditions from 4 million individuals in the English National Health Service - Conditions- Infections of other or unspecified organs - Publication- https://doi.org/10.1016/S2589-7500(19)30012-3 - Clinical codes- ICD-10
ID- 3 - Repository- HDR UK National Phenomics Resource Project - Description- A chronological map of 308 physical and mental health conditions from 4 million individuals in the English National Health Service - Conditions- Lower respiratory tract infections - Publication- https://doi.org/10.1016/S2589-7500(19)30012-3 - Clinical codes- ICD-10
ID- 4 - Repository- HDR UK National Phenomics Resource Project - Description- A chronological map of 308 physical and mental health conditions from 4 million individuals in the English National Health Service - Conditions- Viral diseases (excl chronic hepatitis/HIV) - Publication- https://doi.org/10.1016/S2589-7500(19)30012-3 - Clinical codes- ICD-10
ID- 5 - Repository- HDR UK National Phenomics Resource Project - Description- Incidence of Community-Acquired Lower Respiratory Tract Infections and Pneumonia among Older Adults in the United Kingdom: A Population-Based Study - Conditions- Pneumonia - Publication- https://doi.org/10.1371/journal.pone.0075131 - Clinical codes- ICD-10
ID- 6 - Repository- OpenSAFELY - Description- Codes indicating a diagnosis of influenza or influenza-like illness - Conditions- Documented influenza illness - Publication- - Clinical codes- CTV3 (Read V3) with TPP extensions
ID- 7 - Repository- OpenSAFELY - Description- Codes indicating a diagnosis of a lower respiratory tract infection excluding pneumonia - Conditions- Lower respiratory tract infection - Publication- - Clinical codes- CTV3 (Read V3) with TPP extensions
ID- 8 - Repository- OpenSAFELY - Description- Pneumonia ICD-10 codes - Conditions- Pneumonia secondary care - Publication- - Clinical codes- ICD-10
ID- 9 - Repository- LSHTM Data Compass - Description- Code list: ICD-10 codes for pneumonia - Conditions- Pneumonia - Publication- https://doi.org/10.17037/DATA.00000847 - Clinical codes- ICD-10
ID- 10 - Repository- LSHTM Data Compass - Description- Clinical codelist: Read codes and terms used for pneumonia (CPRD) - Conditions- Pneumonia - Publication- https://doi.org/10.17037/DATA.00001654 - Clinical codes- Medcodes
| Code | Description | BREATHE recommended |
|---|---|---|
| 1 E30 | Influenza due to identified seasonal influenza virus | Y |
| 1 E31 | Influenza due to identified zoonotic or pandemic influenza virus | Y |
| 1 E32 | Influenza, virus not identified | Y |
| 1D01.00 | Meningitis due to Haemophilus influenzae | N |
| 1E30&XN5SG | Influenza due to identified seasonal influenza virus / Influenza virus | Y |
| 1G40&XN1P6 | Sepsis without septic shock / Haemophilus influenzae | N |
| CA40.02 | Pneumonia due to Haemophilus influenzae | N |
| CA40.12 | Pneumonia due to parainfluenza virus | N |
| CA40.1Z | Viral pneumonia, unspecified | N |
| CA42.3 | Acute bronchitis due to Parainfluenza virus | N |
| CA42.4 | Acute bronchitis due to Haemophilus influenzae | N |
| QC01.8 | Need for immunization against influenza | N |
| XN1P6 | Haemophilus influenzae | N |
| Code | Description | BREATHE recommended | Wabe et al, 2021 | Fitzpatrick et al, 2021 | Moss et al, 2020 | Ramsay et al, 2020 | Verfurden et al , 2020 | Iuliano et al, 2018 | Ho et al, 2018 | Bennett et al, 2018 | Acciai et al, 2017 | Hardelid et al, 2017 | Matias et al, 2016 | ONS, 2016 | Fleming et al, 2016 | Cromer et al, 2014 | Auger et al, 2014 | Green et al, 2013 | Henderson et al, 2006 | HDR UK National Phenomics Resource Project 2 | HDR UK National Phenomics Resource Project 3 | HDR UK National Phenomics Resource Project 4 | HDR UK National Phenomics Resource Project 5 | Open Safely 8 | LSHTM Data Compass 9 | |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| A41.3 | Sepsis due to Haemophilus influenzae | |||||||||||||||||||||||||
| A49.2 | Haemophilus influenzae infection, unspecified site | |||||||||||||||||||||||||
| J09 | Influenza due to certain identified influenza viruses | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | ||||||||
| J10 | Influenza due to other identified influenza virus | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | |||||||
| J10.0 | Influenza with pneumonia, seasonal influenza virus identified | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | ||||||
| J10.1 | Influenza with other respiratory manifestations, seasonal influenza virus identified | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | ||||||||||
| J10.8 | Influenza with other manifestations, seasonal influenza virus identified | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | ||||||||||
| J11 | Influenza due to unidentified influenza virus | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | |||||||
| J11.0 | Influenza with pneumonia, virus not identified | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | ||||||
| J11.1 | Influenza with other respiratory manifestations, virus not identified | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y | Y |