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1 🔊3.06 Read and listen to the text. Where do you think this text is from?a a biology textbook b a public information leaflet c a scientific report 2 Match the words in blue in the text with the definitions.1 destroy completely (verb) 2 a substance the body produces to fight disease (noun) 3 through the mouth (adverb) | 3 Answer the questions.1 Which disease no longer exists? 2 How are most vaccines applied to the body? 3 What cells produce antibodies? 4 Who needs the yellow fever vaccine? 4 USE IT! Work in pairs. Ask and answer the questions.1 Which diseases are mentioned in the text? What are they in Vietnamese? 2 Which vaccinations are compulsory in Việt Nam? When do you have them? |
| Vaccines Vaccines are used to protect the body against certain dangerous diseases before we come into contact with them. Global vaccination programmes have eradicated or controlled many deadly diseases around the world. For example, smallpox was officially eradicated in 1980. |  |
| What is in a vaccine? Vaccines are biological substances that are made of the same micro-organisms that cause disease. How do vaccines work? Vaccines help develop the body's immunity by imitating a real infection. When the vaccine is introduced into the body, usually by injection or orally, the immune system reacts to the invading substance as if it were a real disease. The white blood cells produce antibodies to attack and destroy the substance in the vaccine. These antibodies then stay in the body and they create immunity. If the body comes into contact with the disease in the future. the immune system will respond immediately and protect against the infection. | Are all vaccines the same? Different types of vaccines are used to immunise against different diseases. When and how often do you need vaccines? Most children are vaccinated against serious childhood diseases when they are babies. Several doses of the vaccines are needed to build up a complete immunity, so the vaccination is repeated three times. Some vaccines, such as the influenza vaccine, are only effective for a short time and need repeating every year. Others, like the yellow fever vaccine, are only necessary if you live in or visit a country where the disease exists.
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