Keep warm to help tame common cold virus

By Jasminee Sahoye

As the frigid weather continues and more people come down with colds, a Yale University study indicates cold air could make you more susceptible to catching cold and that the virus reproduces better in cooler temperatures.

However, cold air does not cause colds and what causes a cold is exposure to a virus, the study confirms.

Lead author Dr. Akiko Iwasaki of the university’s School of Medicine says; “We found that the innate immune response to the rhinovirus is impaired at the lower body temperature compared to the core body temperature … the lower the temperature, it seems the lower the innate immune response to viruses.”

Researchers took cells from the airways of mice, infected those cells with rhinovirus (the cause of the common cold), and incubated them at either 33C or 37C to mimic the conditions of the nose and lungs, respectively.

They found that at 33 degrees, the cells had a reduced immune response to the virus, allowing it to replicate more quickly. So it could be assumed why in humans, viruses tend to infect our nasal cavities and cause colds as opposed to infecting our lungs and causing pneumonia – because the higher temperature in the lungs allows for better immunity.

Many people run and bike in the cold and a 2007 study in the journal Medicine and Science in Sports and Exercise says the body takes up more oxygen and the heart pumps more efficiently in temperatures just above freezing.  Iwasaki says cold air is a known trigger for asthma attacks and “something I see commonly is patients who tend to flare if they combine cold air exposure with exercise.”

He added that patients with chronic obstructive pulmonary disease tend to have more flares when the temperature drops, according to a 2013 study. A 1998 study published in Chest also suggests patients feel more short of breath in cold air and a 1999 study in the ERJ suggested their lung function also drops in cold weather.

Studies have long shown that patients with cold-induced angina can get attacks with cold air exposure but according to a 2010 study in the Canadian Journal of Cardiology, exercise at -20C causes an increased strain on the heart in any patient with coronary disease.

Dr. Michael Allan, a family physician and professor at the University of Alberta, led a team that conducted evidence-based research, summarized evidence on key health issues and provided that information to thousands of doctors and other health care providers.

Every year, adults typically get a cold two to three times while children under two get sick about six times. The common cold includes a sore throat, stuffy nose, cough and general uneasiness for one to three days or even lasting more than a week.

Some research suggests adults could get a small or moderate benefit from a combination of antihistamines and decongestants with acetaminophen or ibuprofen, he said. Antihistamines include products like Benadryl or Sudafed, while acetaminophen is more commonly known as Tylenol and ibuprofen as Advil.

Allan says children under five shouldn’t take any antihistamines but if they’re dealing with aches, pains or a sore throat, acetaminophen or ibuprofen are good choices, the latter being the best option.

Honey is a promising candidate to tame a child’s cold but not for babies 12 months and under. For other youngsters, Allan said, research points to 2.5 to 10 millilitres (half a teaspoon to two teaspoons) of honey right before bed to help kids and parents sleep through the night.

Over-the-counter cough medicine Cold FX was looked at in several studies with inconsistent results across the board. Some research suggested it worked while others said it didn’t.

Allan’s review spanned hundreds of studies, analyses and reviews.

Overall, he recommends old-fashioned bed rest and staying away from work or school so you don’t spread germs.