The common cold is a viral infection of your upper respiratory tract — your nose and throat. Although usually harmless with recovery time lasting a week or two, a cold may involve a number of symptoms, including runny nose, sore throat, cough, watery eyes, sneezing, and congestion. There are over 62 million annual occurrences of the common cold along with 20 million school days lost annually in the U.S., according to the National Center for Health Statistics. Rhinoviruses, of which there are over 100 different types, are estimated to be the culprit for about 35 percent of these cases.

There are an additional 100 or so other types of virus that may cause colds found worldwide. Enteroviruses, which are small viruses made of ribonucleic acid (RNA) and protein, cause an estimated 10 to 15 million or more symptomatic infections a year in the U.S. Enteroviruses can be found in an infected person's feces (stool), eyes, nose, and mouth secretions (such as saliva, nasal mucus, or sputum), and blister fluid. Second only to the "common cold" viruses, enteroviruses cause many different symptoms, most of which are not serious and resolve on their own without treatment.

No matter where you escape for a summer vacation, then, summer cold viruses will be there, too. People routinely become exposed to rhinoviruses and enteroviruses by:

  • Coming into contact, such as touching or shaking hands, with an infected person.
  • Touching objects or surfaces that have the virus on them.
  • Changing diapers of an infected person.
  • Drinking water with the virus in it.

Although the possibility of catching a cold in the summer months is one-in-four compared to winter months, certain factors commonly increase the risk.

Causes of The Summer Cold

Airplane flights pose a particular risk since they may involve 400 potential sources of infection — excuse me, passengers — and there is a high probability that at least one if not several fellow travelers will be experiencing a cold. The confined space with refiltered air is an ideal environment for transmission of airborne disease. Experiments have shown that the chances of catching a cold are directly related to the number of hours of exposure to infection. That means you are much more likely to get a cold on a long haul flight than on a short hop.

Travel in and of itself increases the risk of viral infection. As you have probably been exposed to the common viruses in your home town, you are less likely to become infected by them. While traveling, though, you will undoubtedly encounter new viruses, to which you have no immunity. And this contanct occurs not only once you arrive at your destination but also all along the way; while moving through airports, train stations and bus stations, you may come into contact with people from around the world even if you yourself are only going a short distance. In fact, contemporary air travel is the main reason why influenza spreads so rapidly around the world during an epidemic.

Air conditioning is another likely contributor to any summertime infection. The lining of your nose is protected against infection by a thin layer of mucus. Air conditioners extract moisture from the air yet they do the same to the nostrils of your nose; in this way, they predispose you to infection. It is also known that viruses reproduce better in a cold nose, so the air-conditioned cool is also supporting the growth of viruses.

Finally, stress, no matter its cause, will lower your resistance to infection by depressing your immune response. Holidays create as much stress as they cure. Concerns about travel arrangements as well as home security leave us susceptible to infection.

Prevention and Cures

You may not be able to avoid touching contaminated surfaces while in public areas, but you can avoid touching your face, especially around the nose and mouth. You can also wash your hands upon arrival as well as before you eat or drink.

Because with each transmission, the cold virus changes, there is no vaccination and no cure for the common cold. Yet all the popular home remedies do at least help to relieve symptoms and possibly, they move things along more quickly. The usual directives include:

  • Drink plenty of fluids.
  • Take extra Vitamin C.
  • Eat hot soup.
  • Drink hot tea with honey for a sore throat.
  • Take a long and steamy shower to open up the nasal passages.
  • Sit in direct sunlight.

Admittedly, most of these actions do not sound very appealing when the thermometer is high, but balmy summer weather offers at least one thing winter does not: many more comfortable places to sit in the fresh air and sunlight.

One caveat: Vitamin C (ascorbic acid) as a treatment and preventative for the common cold has been a subject of controversy for 70 years. In a recent study, researchers found regular supplmentation of vitamin C reduced the duration and severity of colds. In adults, the duration of colds was reduced by eight percent and in children by 14 percent, while severity was also reduced by regular vitamin C administration. In other words, it is necessary to take vitamin C on a daily basis to feel its full effect.

Source: Hemila H, Chalker E.Vitamin C for preventing and treating the common cold. Intervention Review. 2013.