1. Organisation for Economic Co-operation and Development Definitions, sources and methods
2. Centers for Disease Control and Prevention Interim Guidance for Influenza Outbreak Management in Long-Term Care Facilities http://www.cdc.gov/flu/professionals/infectioncontrol/ltc-facility-guidance.htm
3. Public Health England PHE guidelines on the management of outbreaks of influenza-like illness (ILI) in care homes 2016 https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/573143/ILI_in_care_homes_291116.pdf
4. Public Health Medicine Communicable Disease Group Public Health Guidelines on the Prevention and Management of Influenza Outbreaks in Residential Care Facilities in Ireland 2015/2016 Health Service Executive https://www.hpsc.ie/a-z/respiratory/influenza/seasonalinfluenza/guidance/residentialcarefacilitiesguidance/File,13195,en.pdf