Chinese officials studying the Wuhan coronavirus say most of the cluster cases they have observed from a study are within families.

Cluster cases generally refer to “more than two infected cases within a limited space,” Wu Zunyou, a virus expert with China’s Center for Disease Control and Prevention said.

Wu told reporters Tuesday that from a study of more than 1,000 cluster cases, 83% were identified as family clusters. 

Other cluster cases appeared to be from schools, supermarkets or places of work which appeared to be caused by “poor awareness of protection,” such as not wearing masks.

How do you protect yourself and others?

Officials at Tuesday’s press conference reminded the public: if you have infected family members, rooms should be well ventilated, practice good hand hygiene, avoid public gathering and meal-sharing, and employ good health practices if you have to take public transportation.

The World Health Organization has advised people to avoid close contact with anyone showing symptoms of respiratory illness, such as coughing and sneezing.

Scientists believe this coronavirus started in another animal and then spread to humans, so health officials recommend cooking meat and eggs thoroughly.

But in general, the public should do “what you do every cold and flu season,” said Dr. John Wiesman, the health secretary in Washington state — where the first US case of Wuhan coronavirus was confirmed.

That includes washing your hands often with soap and water for at least 20 seconds, covering your mouth and nose when you cough or sneeze, and disinfecting the objects and surfaces you touch if you are ill.

If you or your doctor suspect you might have the coronavirus, the CDC advises wearing a surgical mask.