A risk factor is something that increases your likelihood of getting a disease or condition.
It is possible to develop a cold or influenza with or without the risk factors listed below. However, the more risk factors you have, the greater your likelihood of developing a cold or influenza. If you have a number of risk factors, ask your doctor what you can do to reduce your risk.
The vast majority of the population in any given area may get colds or influenza during the course of a year. The average rate for adults in the US is 3 or 4 infections per person per year. Children get even more.
Risk factors include:
Smoking greatly increases the frequency of colds in adults. Smokers are also at a higher risk for complications from colds and the flu.
Colds and influenza are passed through person-to-person contact, so people who do not wash their hands are at higher risk of spreading and contracting colds or influenza. Also, touching your nose, mouth, and eyes with contaminated fingers can spread germs to yourself.
People in crowded living conditions are at an increased risk, as well.
People who have certain medical conditions are at a higher risk for complications. Examples include:
Children and the elderly are at increased risk for complications.
People with physical or mental disabilities may have trouble practicing preventive measures, and they may not be able to easily communicate their symptoms. These issues place them at an increased risk for getting sick and for having complications.
Common cold. Merck Manual Professional Version website. Available at: http://www.merckmanuals.com/professional/infectious-diseases/respiratory-viruses/common-cold. Updated April 2014. Accessed August 15, 2017.
Influenza. Merck Manual Professional Version website. Available at: http://www.merckmanuals.com/professional/infectious-diseases/respiratory-viruses/influenza. Updated April 2014. Accessed August 15, 2017.
Influenza in adults. EBSCO DynaMed website. Available at:https://www.dynamed.com/condition/influenza-in-adults. Updated September 27, 2016. Accessed August 15, 2017.
Upper respiratory infection (URI) in adults and adolescents. EBSCO DynaMed website. Available at:https://www.dynamed.com/condition/upper-respiratory-infection-uri-in-adults-and-adolescents-18. Updated April 10, 2017. Accessed August 15, 2017.
3/5/2010 DynaMed Systematic Literature Surveillancehttps://www.dynamed.com/condition/upper-respiratory-infection-uri-in-adults-and-adolescents-18: Falagas ME, Karamanidou C, Kastoris AC, Karlis G, Rafailidis PI. Psychosocial factors and susceptibility to or outcome of acute respiratory tract infections. Int J Tuberc Lung Dis. 2010;14(2):141-148.
2/3/2015 DynaMed Systematic Literature Surveillancehttps://www.dynamed.com/condition/upper-respiratory-infection-uri-in-adults-and-adolescents-18: Rantala A, Jaakkola JJ, Jaakkola MS. Respiratory infections in adults with atopic disease and IgE antibodies to common aeroallergens. PLoS One. 2013;8(7):e68582.
Last reviewed September 2018 by David L. Horn, MD, FACP Last Updated: 11/11/2020