It is possible to have influenza and other respiratory illnesses at the same time. This is called coinfection.1
This information is intended for healthcare professionals only.
Potential Cocirculations
Coinfections of RSV, influenza, and COVID-19
Compare the symptoms of RSV, influenza, and COVID-19
Common signs and symptoms include
RSV2,3
Influenza4
COVID-195
Symptom onset
Gradual
Sudden
Gradual
Body aches
Uncommon
Common
Common
Cough
Common
Common
Common
Fever
Common
Common
Common
Fatigue
Sometimes (more common in children)
Common
Common
Diarrhoea/vomiting
Uncommon
Sometimes (more common in children)
Common
Difficulty breathing
Common
Sometimes
Common
Runny nose/nasal congestion
Common
Sometimes
Common
Sneezing
Common
Sometimes
Uncommon
Sore throat
Common
Sometimes
Common
Headache
Common (in older adults)
Common
(in older adults)
(in older adults)
Common
Common
Loss of taste/smell
Uncommon
Uncommon
Common
Decreased appetite
Common
Uncommon
Uncommon
How common is coinfection?
Coinfections of respiratory diseases are rare, mostly due to competition between the viruses during infection.6-8
What happens if patients become coinfected?
The results of a coinfection may be severe:
- Patients in the UK with a coinfection of COVID-19and influenza were twice as likely to die as those withCOVID-19alone8
- A 2017 South African study found that, compared to those who had infection with influenza alone, those with a coinfection of RSV and influenza increases the odds of developing a life-threatening disease and requiring a longer stay in the hospital9
- Compared with those who had infection with influenza alone, children in the US younger than 18 years of age coinfected with COVID-19and influenza were more likely to be placed on a ventilator10
References:
1.
Influenza (Flu): Frequently asked influenza (flu) questions: 2022-2023 Season. Centers for Disease Control and Prevention. Updated November 21, 2022. Accessed July 7, 2023. https://www.cdc.gov/flu/season/faq-flu-season-2022-2023.htm
2.
Respiratory Syncytial Virus Infection (RSV): Symptoms and care. Centers for Disease Control and Prevention. Updated September 6, 2023. Accessed September 12, 2023. https://www.cdc.gov/rsv/about/symptoms.html
3.
Older adults are at high risk for severe RSV infection. Centers for Disease Control and Prevention. Published April 2023. Accessed July 7, 2023. https://www.cdc.gov/rsv/factsheet-older-adults.pdf
4.
Influenza (Flu): Flu symptoms & complications. Centers for Disease Control and Prevention. Updated October 3, 2022. Accessed July 7, 2023. https://www.cdc.gov/flu/symptoms/symptoms.htm
5.
COVID-19: Symptoms of COVID-19. Centers for Disease Control and Prevention. Updated October 26, 2022. Accessed July 7, 2023. https://www.cdc.gov/coronavirus/2019-ncov/symptoms-testing/symptoms.html
6.
Meskill SD, Revell PA, Chandramohan L, Cruz AT. Prevalence of co-infection between respiratory syncytial virus and influenza in children. Am J Emerg Med. 2017;35(3):495-498. doi:10.1016/j.ajem.2016.12.001
7.
Waterlow NR, Flasche S, Minter A, Eggo RM. Competition between RSV and influenza: limits of modelling inference from surveillance data. Epidemics. 2021;35:100460. doi:10.1016/j.epidem.2021.100460
8.
Stowe J, Tessier E, Zhao H, et al. Interactions between SARS-CoV-2 and influenza, and the impact of coinfection on disease severity: a test-negative design. Int J Epidemiol. 2021;50(4):1124-1133. doi:10.1093/ije/dyab081
9.
Mazur NI, Bont L, Cohen AL, et al. Severity of respiratory syncytial virus lower respiratory tract infection with viral coinfection in HIV-uninfected children. Clin Infect Dis. 2017;64(4):443-450. doi:10.1093/cid/ciw756
10.
Adams K, Tastad KJ, Huang S, et al. Prevalence of SARS-CoV-2 and influenza coinfection and clinical characteristics among children and adolescents aged <18 years who were hospitalized or died with influenza—United States, 2021-22 influenza season. MMWR Morb Mortal Wkly Rep. 2022;71(50):1589-1596. doi:10.15585/mmwr.mm7150a4
