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Cold, Flu, & Cough Health Center

Doctor Talk: A Glossary of Flu Terms

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    Medical terms linked to the flu don't have to be confusing. Here are brief definitions for things you may hear your doctor or friends say.

    Antibacterial. It can kill bacteria or slow their growth.

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    Antibiotics. Medicines that treat infections by killing bacteria. They don’t work on viruses, like the flu.

    Antibiotic resistance. When bacteria get used to an antibiotic and no longer respond to it. This happens because doctors sometimes prescribe antibiotics to people who don’t need them.

    Antiviral agents. Medicines that treat viral infections. Antivirals like oseltamivir phosphate (Tamiflu), peramivir (Rapivab), or zanamivir (Relenza) can be used to treat the flu or to help prevent it in people at high risk. As a treatment, they work best if you get them within the first 2 days after your symptoms start.

    Bacteria. Microscopic one-celled organisms. Some of them cause illness.

    Bronchitis. Inflammation of the airways leading to your lungs. Causes include viruses, bacteria, and irritants like cigarette smoke.

    Common cold. A viral infection of the upper respiratory tract. Colds aren’t related to the flu.

    Germs. Any microbes, including viruses or bacteria.

    Immune system. The group of organs and special cells in your body that protect you from disease.

    Immunity. Protection from disease.

    Immunization. A way to make you immune to a disease, specifically by taking a vaccine.

    Influenza. Also called the flu, it’s a common but sometimes serious viral infection of your lungs and airways. It can cause congestion, fever, body aches, and other symptoms.

    Microbe. A microscopic organism.

    Nasal vaccine. A vaccination, like FluMist, that you breathe in, rather than one given by shot.

    Pneumonia. An inflammation of the lungs. Symptoms are fever, chills, cough, chest pain, and trouble breathing. It’s often caused by a viral or bacterial infection.

    Reye's syndrome. A life-threatening brain and liver disease that can follow infection with a virus, like the flu. It’s most common in children. It’s often linked with taking meds that contain aspirin.

    Sinusitis. Swollen sinuses, especially the ones around your nasal passages. Causes include infection with a virus or bacteria.

    "Stomach flu." The common name for tummy troubles caused by any number of different microbes. It has no relation to flu.

    Vaccine. A substance that helps protect against certain diseases. Vaccines contain a dead or weakened version of a microbe. It helps your immune system recognize and destroy the living microbe during a future infection.

    Virus. A microscopic organism that invades living cells to reproduce. Many, like influenza, cause illness. Antibiotics don’t affect a virus.

    WebMD Medical Reference

    Reviewed by Jennifer Robinson, MD on May 10, 2015

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