Sheila M. Martin-Corbin
Typically, germs can linger on an inanimate object, such as a tabletop, doorknob or faucet handle for long periods of time. When a person touches the same doorknob or object which was grasped by someone ill with the flu or a cold, for example, he or she can pick up the germs left behind by that infected person. If she then touches her eyes, mouth or nose before washing her hands, she takes the risk of becoming infected with the pathogen-causing disease. Consider the flu virus, which could become weakened and cannot easily survive drying out; however, this virus can become more infectious in colder temperatures when spread through droplets such as the air. Therefore, when an infected person coughs or sneezes, droplets of the microorganism are expelled into the air and infect other people.
Droplets travel only about three feet because they're usually too large to stay suspended in the air for a long time. However, if a droplet from an infected person comes in contact with one's respiratory organs such as the nose or mouth, he or she may soon experience symptoms of the illness. Crowded, or indoor environments can favor airborne pathogens and may promote the chances of droplet or particle transmission of the germ. Such environmental conditions may explain the increase in respiratory infections during the winter months.
Tuberculosis and SARS are two infectious diseases usually spread through the air, in both particle and droplet forms. Misconceptions and myths of how people get the cold can be discussed and clarified at this time.
Some diseases that are commonly spread by coughing or sneezing include:
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Common cold,
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Influenza,
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Strep throat
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Tuberculosis,
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Whooping cough
Contaminated foodstuffs or drinking water are other ways by which diseases are spread. The risk increases when people do not wash their hands before preparing food, or untreated sewage being released into a drinking water supply. E. coli is a bacterium present in certain foods, such as undercooked hamburger or unwashed fruits or vegetables. When a person eats foods contaminated with E. coli, chances are he or she will experience food poisoning and become infected with the bacterium. This is a typical mode of transmission for diseases such as cholera, hepatitis A , polio and salmonella.
Vector-borne diseases, caused by pathogens, transmitted by insects and ticks is another method of spreading infectious diseases. However, the best way to fight the disease is to avoid being bitten by such insects and controlling the insect population. If preventative measures fails, drugs like antibiotics have been developed to kill the bacteria without harming human cells. Some diseases that can be vectored to humans include malaria, yellow fever, dengue fever, West Nile virus, and Lyme disease.
The vector-borne spread of germs happens when an insect that carries the germ on its body or in its intestinal tract lands on a person or bites the person. The germs travel into the body and can make the person sick. They use the insect's body to multiply, which is necessary before the germs can infect a new host.
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