It is often quoted that 50% of people will succumb to an upper respiratory tract infection in the course of a year. The usual pathogens involved are viruses.
Rhinoviruses with more than 100 serotypes are the most common pathogens, causing at least 25% of colds in adults. Coronaviruses may be responsible for more than 10% of cases. Parainfluenza viruses, respiratory syncytial virus, adenoviruses and influenza viruses have all been linked to the common cold syndrome. All of these organisms show seasonal variations in incidence. The cause of 30% to 40% of cold syndromes has not been determined.
Purushothama V. Dasaraju and Chien Liu.
The natural history of a cold is typically complete resolution within seven to ten days. There is no cure and regardless of what treatment is offered most people are miserable during that time with a runny nose, cough, sneezing, fatigue and sore throat. This is one of the commonest reasons people seek medical advice if not the most common reason. Colds are typically seasonal, highly infectious and responsible for a huge cost to society . Not to mention the risk of being offered inappropriate treatment, especially antibiotics.
We might ponder a philosophical question- Who benefits from a cold? Certainly viruses do- they spread from host to host at an alarming rate. However viruses that cause a cold do not mutate like the flu virus does, so spreading through the community doesn’t support their evolution. The condition is not fatal therefore it does not appear to support the host’s natural selection. So what is the point of an infection that makes us miserable up to three or four times a year? We lose time off work, we take medicines that provide temporary relief and life simply becomes a little more difficult. Possibly the only part of society that benefits are those who sell medicines!
Research now suggests that not everyone suffers to the same extent.
The epidemiologic data suggest that endurance athletes are at increased risk for URTI during periods of heavy training and the 1-to 2-week period after marathon-type race events.
Nieman
Even after adjustment for other variables, men were significantly more likely to ‘over-rate’ their symptoms in comparison with the clinical observer than were women.
Macintyre
We found that high physical activity was associated with a lower risk of contracting URTI for both men and women.
Fondell et al
Data analysis showed that higher incidence of URTI was significantly associated with increased training ( tennis) duration and load, and competition level, on a weekly basis.
Novas et al
The risk of self-reported manifestations of the common cold was higher in workers who reported symptoms of depression.
Kim et al
Most of the relevant studies show a significant relationship between psychosocial factors and the onset or progression of acute respiratory tract illness. However, the psychosocial variables were not consistently evaluated across the included studies, and different methodological approaches were used to examine the association between psychosocial factors and acute respiratory tract illness.
Falagas et al
And finally most intriguing of all
Training in meditation or exercise may be effective in reducing ARI illness burden.
Barrett et al
This suggests that the URTI may serve as a barometer for stress in many people. This perspective may help those who advise or care for people who are experiencing symptoms of an URTI to consider what if anything can be done to address the other issues in their lives that may be problematic. By corollary people presenting for help with an URTI require the most skilled healthcare and not just a lecture on how paracetamol is the only treatment available.
Photo by Brittany Colette on Unsplash
