Viral Upper Respiratory Infections (Colds and Influenza) Causes

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 three or four infections per person per year. Children get even more.

Risk factors include:

Smoking

Smoking greatly increases the frequency of colds in adults. Smokers are also at a higher risk for complications from colds and the flu.

Poor Hygiene

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.

Crowded Populations

People in crowded living conditions are at an increased risk, as well.

Medical Conditions

People who have certain medical conditions are at a higher risk for complications. Examples include:

• People who are sick
• People who have cardiac, respiratory, or kidney disease
• People who have suppressed immune systems
• Women who are pregnant

Age

Children and the elderly are at increased risk for complications.

Disability

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 complications.

Stress and Other Mental Health Factors

You may be an increased risk for contracting a cold if you are under a lot of stress or if you feel anxious or depressed .

References

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3/5/2010 DynaMed's Systematic Literature Surveillance DynaMed's Systematic Literature Surveillance : Falagas ME, Karamanidou C, Kastoris AC, Karlis G, Rafailidis PI. Psychosocial factors and susceptibility to or outcome of acute respiratory tract infections. I nt J Tuberc Lung Dis.2010;14(2):141-148.