The most common ailments were respiratory, heart, and neurological diseases, as well as digestive complaints. Some also suffered burns from attempting different methods to keep warm.

Many major hospitals in Hanoi such as Bach Mai, Saint Paul, the National Children's Hospital and the National Burn Institute also experienced a surge in the number of patients.

More than 120 children have been brought to Saint Paul hospital for treatment.

Some people suffered serious burns as an indirect result of the cold weather. An elderly man in Bac Ninh province fell into a wood-fired space heater and burned himself. He also had breathing difficulties. An 8-year-old child was also burnt when an electric hot water bag exploded.

Those with hypertension and asthma are also vulnerable to the freezing weather and many incidents of strokes have been reported in both young and middle-aged people.

Doctors warn people to try to avoid sudden changes of temperature and early morning exercise.