If you didn't have a functioning immune system, simply brushing your teeth would introduce enough harmful bacteria into your bloodstream to kill you. Luckily, your immune system protects you from these common, everyday bacteria.
Sight unseen, your immune system cells are constantly gobbling up bacteria and blocking viruses from invading your cells. Like your heartbeat or your digestion, the immune response is a function you don't control. But there are plenty of things you can do to lend a helping hand.
1. Good hygiene. The first line of defense is to keep germs at bay by following good personal hygiene habits. Stop infection before it begins and avoid spreading it to others with these easy measures:
- Wash your hands with soap and water before preparing food and after using the bathroom.
- Cover your mouth and nose with a tissue when you sneeze or cough, or cough into your elbow rather than your hand.
- Wash and bandage all cuts. Any serious cut, or animal or human bite, should be examined by a doctor.
- Do not pick at healing wounds or blemishes or squeeze pimples. Doing so allows germs to enter.
2. Vaccination. Many serious infections can be prevented by immunization. While some common side effects, such as a sore arm or low fever, may occur, vaccines are generally safe and effective. Consult your health care provider regarding your immunization status. In general:
- Children should receive the recommended childhood vaccinations.
- Adults should make sure their vaccinations are up to date.
- Travelers should get any necessary additional immunizations.
3. Food safety. Although most cases of food poisoning are not life-threatening, a few may lead to serious medical conditions, including kidney failure and meningitis. You can prevent most cases of food poisoning in your household by preparing and storing your foods safely. The following precautions will help kill germs that are present in the food you buy and help you avoid introducing new bugs into your food at home:
- Wash your hands with soap and water before and after each time you handle a raw food.
- Rinse all meat, poultry, and fish under running water before cooking. Rinse all fruits and vegetables under running water before cooking or serving them.
- Separate raw foods and cooked foods, and never use the same utensils or cutting boards with cooked meat that were used with raw meat.
- Cook foods thoroughly, using a meat thermometer to ensure that whole poultry is cooked to 180° F, roasts and steaks to 145° F, and ground meats to 160° F. Cook fish until it is opaque.
- Defrost foods only in the refrigerator or in the microwave.
4. Healthy travel. If you are planning a trip, ask your doctor if you need any immunizations. Discuss your travel plans with your physician at least three months before you leave. In addition:
- If you are traveling to an area where insect-borne disease is present, take and use an insect repellent containing DEET. In many tropical regions, mosquitoes can carry malaria, dengue, yellow fever, Japanese encephalitis, and many other serious infections. In many parts of the United States, ticks in meadows and woods carry Lyme disease or other diseases.
- Avoid getting any unnecessary shots, immunizations, or even tattoos abroad. Needles and syringes (even the disposable ones) are reused in some parts of the world.
5. Clean water. Some countries do not follow stringent standards of water safety. If you have any doubt about the food or water while traveling, take these precautions:
- Do not consume ice while traveling. Freezing does not kill all infectious microbes.
- Drink only bottled drinks — such as soft drinks or bottled water — that have secure caps. Be aware that some fruit juices contain impure local water.
- Boil all tap water before drinking or drink only bottled water; use bottled or boiled water to brush your teeth.
- Do not eat uncooked vegetables, including lettuce; do not eat fresh, uncooked fruit you have not peeled yourself.
- Do not consume dairy products (milk may not be pasteurized).
- No matter where you are, avoid drinking untreated water from lakes and streams, which can contain disease-causing organisms from human or animal waste. If you must drink the water, bring it to a rolling boil for one minute to reduce the chance of infection.
6. Safe sex. The only sure way to prevent sexually transmitted diseases (STDs) is to not have sexual intercourse or other sexual contact. But the next best choice is to follow these safer sex guidelines:
- Engage in sexual intercourse only with one partner who has been tested and who is having sex only with you.
- Use a latex or polyurethane condom or a female condom every time you have sex.
- For oral sex, use a latex or polyurethane male condom or a female condom.
- For anal sex, use a latex or polyurethane male condom.
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