When seasons change, colds and flu are common. Young children in particular can easily get ill and that causes worries. Cold and flu symptoms - sneezing, coughing, sore throat and fever - are mostly caused by a mild infection in the upper respiratory system.

A fever of 38 to 40 degrees Celsius, muscular pain and exhaustion are the key symptoms of flu, though none of these is usually associated with colds.

Generally, colds and flu are caused by a virus infection. Symptoms like blocked nose and sneezing usually disappear in 10 to 14 days. If they continue for longer than two weeks see a doctor, as you may have an allergy, sinusitis or a more serious condition that needs treatment.

Complications such as pneumonia and middle-ear infections are more likely to affect the elderly, those with heart disease, diabetes or asthma, pregnant women and young children under five years old. These people need special care: Negligence can cause serious problems later.

Effective treatment for colds and flu is easy and can be done by the patients themselves. Get sufficient rest, keep your body warm, ensure good air circulation in your room and avoid polluted environments, and drink a lot of water - preferably warm - to help your body get rid of mucous and phlegm.

To prevent spreading the virus, stay away from those with a cold or flu, avoid taking young children to crowded places, where flu virus can easily spread, and consider getting vaccinated against flu. If you already have flu or a cold, cover your nose and mouth with a handkerchief, a mask or your hand when you sneeze or cough so that you don't spread the virus to others.

Anjana Sachabudhawong is a doctor at Samitivej Sukhumvit Hospital's Paediatric Pulmonology and Critical Care centre.

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