Seasons and Symptoms of Colds and Allergies
Maintaining Your Health on Mackinac
By Yvan Silva, M.D.

Symptoms relating to colds and allergies are often confusing; there are some similarities, but the differences are important to know. This article outlines details of these conditions with practical ways to deal with the ailments they cause.

Many people believe that the common cold is something you catch during cold weather, with exposure to sudden drops in temperature, cold drafts, or getting your head wet. That is not entirely true. And kissing is not any more likely to cause it than sitting in a windy draft.

Thirteen pairs of volunteers kissed for up to one and one half minutes, one in each pair had been experimentally infected with a cold virus and the other did not have a cold or antibodies to the virus. Only one of 13 developed a cold.

The term cold probably refers to seasons; these upper respiratory tract infections are usually more common in fall and winter. During these seasons, humidity is low and cold viruses thrive better. In these environments, nasal passages tend to dry out and become more vulnerable to viral infection. People spend more time indoors and spread viruses to each other more frequently. The onset of spring is also a time for colds to become prevalent.

Cold viruses are spread by touching infectious respiratory secretions from the skin of an infected individual; you can pick them up from doorknobs, telephones, and towels or by inhaling them from the air in coughed up drafts. They can survive for several hours on household surfaces or in the air you breathe. One way or another, they have to lodge in the upper nasal passages and the naso-pharynx where they can multiply and invade the body. They can also multiply in the eyes and find their way there through the tear ducts which drain into the nose. Psychological stress is believed to further increase susceptibility.

There are more than 200 different strains of viruses that can cause colds or flu. About one third of colds are caused by rhinoviruses - from the Greek rhin, for nose - which grow best at temperatures around 91 degrees Fahrenheit - the temperature of human nasal mucosa. About one billion colds occur each year in this country. Young and middle-aged adults average two to four colds each; women get more colds than men, possibly because of closer contacts with cold-infected children; children get six to eight episodes.

Symptoms are familiar to most - runny nose, sneezing, a scratchy throat, bouts of coughing, a vague headache, and generalized muscular ache that increases with activity. They come on gradually with a period of feeling unwell; you can awake with them even though you're in good physical shape. Symptoms are milder than those you get with the flu and you are most infectious during the first three days from the appearance of symptoms. During this time the body's immune systems are attacking viruses and decreasing their numbers. Most sufferers are completely recovered within 10 days. Symptoms can last anywhere from three days to several weeks.

What can you do? Clearly, prevention is best. Frequent hand washing, especially after contact, is a very efficient preventive measure. Personal items should not be shared. Avoid getting the viruses into your nose, and since they can only get there directly by contact, you must keep your hands away from your nose and your eyes.

One study revealed that most people bring their hands and fingers into contact with their eyes and nasal orifices once every three hours or so. Move away from people who are coughing or sneezing around you. Cover your own coughs and sneezes with disposable tissues - cloth kerchiefs promote viral growth, especially when moist.

There is no benefit from the adage, feed a cold, starve a fever. Let your appetite be your guide. A fever increases the rate at which the body burns calories and loses fluid. Decreasing caloric intake only leads to a bigger caloric deficit.

Dehydration is a serious consequence, especially in children. This is the rationale for advising intake of plenty of fluids. Thirst is not a good enough guide, because this sensation becomes blunted.

Vitamin C has not been proven to prevent colds, but large doses are acknowledged to shorten the length by about one day and decrease the intensity of symptoms some.

Chicken soup works by thinning out mucous and draining sinuses better, perhaps because it contains a natural amino acid.

Sneezing, coughing, and stuffy and runny noses are common to colds and allergies sufferers. If you have a recurring fever and a discolored nasal discharge, you probably have a cold. If you suffer from a continuous series of colds, you probably have an allergy. While the mechanism of infection of cold viruses is spread from person to person, allergies are not; they are rather, the body's reaction to allergens, particles that are inhaled from the air during certain seasons. Tree pollen season is from February or March through May. Grass pollens run high from May through July. Weed season is August through the fall; ragweed is an allergen that may prevail through the frost of late fall, early winter.

One plant is known to generate one million grains of pollen. Daily pollen counts are available regionally and are important to people with serious allergies to pollen. The peak pollen time is 5 a.m. to 10 a.m. and it is best to stay indoors then. Close windows and doors and car doors when traveling. Showering and changing clothes often helps in lowering direct contact - skin and clothing can retain pollen. Showering also helps with humidity of the nasal passages and decreases sneezing and congestion. Besides seasonal allergies, year-around allergies to dust mites, dogs and cats, and mold can occur.

Some 50 million Americans are estimated to suffer from allergies. Not many people understand their own allergies and there is much misunderstanding about identification of causes and treatment of symptoms. Prevention of allergic reactions is very important because allergies can range from annoying symptoms to the high risk of death from serious anaphylaxis.

You are born with an immune system that contains information transmitted from your parents. This inherited information allows your body to recognize agents that are potentially harmful so that, when threatened by an antigen, a foreign agent, your body recognizes it as non-self. Rapidly, your body reacts with an already present internal antibody to form an antigen-antibody complex and neutralize the challenge. After birth, your body continues to react to antigenic challenges and, given the vitality and versatility of the immune system, you continue to manufacture antibodies to new antigens, storing them for potential future use.

An allergy, thus, refers to an abnormal reaction to antigenic substances or allergens. Allergens may be inhaled, swallowed, or enter the body through the skin, by contact or puncture, to trigger a reaction from the immune system. It has long been thought that certain childhood diseases, like measles and chicken pox, when contracted, conferred permanent immunity for the rest of life because the body made antibodies that would ward off further attacks. Many believed that measles, for instance, protected children from developing allergies as they grew up. But, a recent study done in Finland and published in a leading medical journal showed that children and adolescents who had measles were more likely to develop allergies.

A description of common allergens follows:

Animal Dander: People are not allergic to the hair of animals as is widely thought. They are, rather, allergic to a protein found in saliva, dander (dead skin flakes), or urine of an animal with fur. Symptoms of animal allergy include sneezing, itchy, runny nose, and itchy, swollen eyes and throat.

Dust Mites: These microscopic organisms are found throughout the home in bedding, upholstered furniture, and carpets. Their droppings are the most common triggers of year-round allergy and asthma symptoms. Mites thrive in high humid environments. Symptoms of dust mite allergy include a congested or runny nose with sneezing, commonly in the mornings, itchy, watery eyes, coughing, and wheezing.

Pollen: Commonly known as "hay fever," pollen allergies are among the most common chronic conditions in the United States. Weeds (ragweed, sagebrush, redroot pigweed, and Russian thistle), grasses, and trees produce allergenic pollen. Dry pollens are disseminated by wind and trigger allergy symptoms, which commonly include sneezing, congestion, runny nose, and itchiness in the nose, roof of the mouth, throat, eyes, and ears.

Mold spores: Indoor molds and mildew thrive in humid areas of the home such as damp basements and bathrooms. These fungi produce spores that trigger allergic attacks. Symptoms are similar to those of pollen allergies.

Insect stings: Some people suffer from venom allergy to the bites of certain insects, usually, without knowing it. Beside the local response at the site of an insect bite, the allergy can be life threatening and result in anaphylaxis, which is considered a medical emergency. This severe reaction can include a feeling of warmth, flushing, itching, hives, swelling in the throat, wheezing, light headedness, irregular heart rhythm, nausea, and vomiting, which can progress to shock. Compromise of cardiac and respiratory functions can cause death. Yellow jackets, honeybees, paper wasps, hornets, and fire ants cause most sting reactions.

Medications: A small percentage of people may develop an allergic reaction to some types of medication. Medication allergies can vary and may range from an itchy rash and hives to anaphylaxis.

If you suspect you might be suffering from allergies, you will need your doctor to confirm the diagnosis and devise a treatment plan. When needed, patients are referred to doctors who specialize in allergies. To diagnose the condition, a thorough medical history and physical examination are conducted. Allergy skin tests and blood tests may also be used to determine the types of allergies you have. If you have a severe allergy, especially a medication allergy, you should consider wearing a necklace or bracelet that identifies the allergy so you can be treated effectively in emergencies.

Once you've determined the nature of your allergies, the best way to prevent reactions is to avoid the things that trigger the allergy. If you're allergic to animal dander, keeping cats or dogs or pets is hazardous and you should avoid contact as much as possible. Often, your doctor can prescribe medications to prevent or relieve symptoms. In some cases, people require immuno-therapy, also known as allergy shots - doctors administer, gradually increasing doses of single or multiple allergens to reduce the immune system's reactions to allergens.

Dr. Silva is a professor of surgery at Wayne State University and a resident of Woodbluff on Mackinac Island.