virus

Everyday

1. A virus is a tiny germ, much too small to see, that gets inside living cells and can make people, animals or plants ill. tree →
2. A computer virus is a harmful program that spreads between computers and damages them or steals information. tree →

In the lessons

In science and health, viruses cause colds, flu, chickenpox and measles; they spread by coughs, sneezes and dirty hands, so washing hands and covering sneezes helps. Antibiotics do not kill viruses; vaccines can protect against some of them. In computing and online safety, do not open strange links or attachments, because they may carry a computer virus; antivirus software protects computers.

Examples

• A cold is caused by a virus. tree →
• Wash your hands to stop viruses spreading. tree →
• The flu vaccine protects you from the flu virus. tree →
• Viruses are much smaller than bacteria. tree →
• Antibiotics don't work against viruses. tree →
• The email had a virus, so Dad deleted it. tree →
• The virus spread quickly through the class. tree →

Note

Plural «viruses» (not «virii» or «viri»). A virus is not the same as bacteria: bacteria are living cells and some can be treated with antibiotics; viruses cannot. «Viral» = caused by a virus, or (online) spreading fast. Both «virus» and «germ» are used; germ is a general word.