In the winter months, it seems like everyone is coughing, sneezing, vomiting, or just feeling “under the weather.” Despite our best efforts, we often can’t avoid getting sick. The good news is that the most frequent illnesses are usually uncomfortable but harmless.
Not surprisingly, Ruth Harrison, director of Health Services at the College, cites the common cold and influenza as the most prevalent infectious diseases. Colds and other upper respiratory infections can affect the nose, throat, sinuses and bronchi, air tubes that connect the windpipe to the lungs. The flu is a disease of the lungs that if ignored or left untreated can lead to pneumonia. Both the cold and the flu are caused by viruses, not bacteria.
Viral diseases in general are more common than bacterial infections, for two reasons. Viral particles, which are non-living and consist of a strand of DNA packaged in a protein shell, are much smaller than bacteria, which are unicellular organisms capable of all the functions of life. The size of viruses causes them to be more easily airborne than bacteria, and thus there is a greater chance that they will be transferred from one person to the next. Also, it only takes a few virus particles to invade a host and cause an illness, but the same number of bacteria cells can be easily overwhelmed by the body’s immune system. Other widespread viruses are Epstein-Barr, which causes mononucleosis, and various forms of herpes, that can cause cold sores, chicken pox and even genital herpes.
Many of the symptoms of diseases both viral and bacterial are actually the immune system’s response to the infection. They do not necessarily represent the direct actions of the pathogen itself. For example, the coughing, sneezing, and general malaise of most colds are simply the signs of the body attempting to rid itself of the unwelcome virus. Fevers are the body’s way of killing invaders, as many types of bacteria and viruses do not reproduce or survive well in temperatures above 37 degrees Celsius (normal body temperature). In fact, Dean Roseman, a biologist specializing in virology, molecular biology and immunology, suggests refraining from taking aspirin for mild fevers and instead letting the body go about its business.
Why are illnesses more frequent in winter than other times of the year? It is not true that being cold makes you catch colds, or even that the body’s defenses drop with the temperature. The main reason winter is worst for infectious diseases is that people spend an increased amount of time inside, breathing dry, re-circulated air, and thus we are brought into contact with more bacteria and viruses than at other times of the year. Furthermore, as Dean Roseman noted, certain diseases need a specific concentration of hosts to survive. Williamstown has a small population, but college dorms are very densely populated, providing diseases with that necessary host density.
Winter study can be a particularly dangerous time. Students have been traveling, all over the country and world, and airplanes are one of the best places to catch diseases, again as a result of the recycled air and high population density. Also, because there are different strains of viruses and slightly different types of bacteria throughout the country, students may bring back to campus a strain to which they are immune but which can easily attack students from other regions who lack the appropriate defenses. Dale Newman, nurse practitioner for the Health Center, said that this phenomenon is especially prevalent among first-year students, who have yet to develop sufficien immunities to the wide variety of diseases they will almost certainly be introduced to in their first year of college.
Attempting to prevent diseases will not guarantee a completely cold-free winter, but it can go a long way towards keeping students well. Harrison and Newman had lots of advice for preventing the spread of infections. “Wash your hands,” they said. “Eat well. Sleep well. Exercise, stay hydrated, and don’t share drinks or toothbrushes. Wash your hands! Hands do a lot of carrying, and when you rub your eye, or you sneeze or cough, and then shake hands or open a door, that’s where transmission occurs.”
“Vaccines aren’t perfect, but they’re the best thing we’ve got going,” she said, citing their ability to make possible the eradication of formerly epidemic diseases such as smallpox. In November 2002, the Department of Health Services offered students the opportunity to be vaccinated against the meningococculus bacteria, which causes meningitis and the flu virus. The meningococcal vaccine protects against the four most common forms of the bacteria and lasts for three years. The flu vaccine, on the other hand, must be updated every year to reflect the changing form of the virus. There are over 100 strains of the flu virus that all produce similar effects, so the Center for Disease Control must track which strains are most prevalent and tailor each year’s vaccine, as well as other counter-measures, accordingly.
Treatment of common winter diseases tends to be symptoms-based for viral infections, as there are not many anti-viral drugs available. Decongestants, cough suppressants and the like control the uncomfortable symptoms of a disease but do nothing to speed its eradication. For bacterial infections, however, antibiotics can actually kill the cause of the illness. Antibiotics first suppress and eventually kill the invading bacteria in the body, and most are highly effective. Problems arise when people do not take the instructions for prescription medication seriously. Many people, after taking an antibiotic for a few days, will begin to feel better and assume that they are well enough to not need the rest of the prescribed amount. What they are feeling is the effect of the suppression but not the elimination of the bacteria. This creates a situation in which bacteria that survived the initial attack of the antibiotic and therefore have some slight resistance to it remain in the body and proliferate. Bacteria that are not killed are made stronger, and by neglecting to finish a full course of antibiotics, people create antibiotic-resistant strains. Essentially, it is “genetically engineering the bacteria to be better,” Harrison said.
With a few more months of winter ahead of us, Harrison emphasizes the importance of staying healthy and trying to prevent the spread of diseases. And if you do catch a cold or the Norwalk virus that has been all over campus, remember that “getting sick just makes your immune system stronger.”
For those who would like to learn more about the history of infectious diseases, the Chapin Library has an exhibition entitled “Culture, Society and Disease” on view from now until Valentine’s Day. Also, check out the Center for Disease Control website (www.cdc.gov), the World Health Organization website (www.who.int/en) and All the Virology on the web (www.virology.net).