our body and begin to multiply. Disease occurs when the cells in your body are damaged — as a result of the infection — and signs and symptoms of an illness appear.
In response to infection, your immune system springs into action. An army of white blood cells, antibodies and other mechanisms goes to work to rid your body of whatever is causing the infection. For instance, in fighting off the common cold, your body might react with fever, coughing and sneezing.
Warding off germs and infection
What's the best way to stay disease-free? Prevent infections from happening in the first place. You can prevent infection through simple tactics, such as regular hand-washing, vaccinations and appropriate medications.
- Hand-washing. Often overlooked, hand-washing is one of the easiest and most effective ways to protect yourself from germs and most infections. Wash your hands thoroughly before preparing or eating food, after coughing or sneezing, after changing a diaper, and after using the toilet. When soap and water aren't readily available, alcohol-based hand-sanitizing gels can offer protection.
- Vaccines. Vaccination is your best line of defense for certain diseases. As researchers understand more about what causes disease, the list of vaccine-preventable diseases continues to grow. Many vaccines are given in childhood, but adults still need to be routinely vaccinated to prevent some illnesses, such as tetanus and influenza.
- Medicines. Some medicines offer short-term protection from particular germs. For example, taking an anti-parasitic medication might keep you from contracting malaria if you travel to or live in an area where your risk is high.
When to seek medical care
You should seek medical care if you suspect that you have an infection and you have experienced any of the following:
- An animal or human bite
- Difficulty breathing
- A cough lasting longer than a week
- A fever of 100.4 F (38 C) or more
- Periods of rapid heartbeat
- A rash, especially if it's accompanied by a fever
- Blurred vision or other difficulty seeing
- Persistent vomiting
- An unusual or severe headache
Your doctor can perform diagnostic tests to find out if you're infected, the seriousness of the infection and how best to treat that infection.
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- Viruses - and some virus-like agents. Microbe World. American Society for Microbiology. http://www.microbeworld.org/microbes/virus/default.aspx. Accessed Feb. 16, 2009.
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