Experts warn they've discovered the coronavirus has another method of transmission - it can spread just by people breathing.
The announcement of another deadly way the virus can infect people means the virus could be more even more contagious than previously thought.
Here are the three main ways coronavirus can spread - and how to protect yourself from them.
On Saturday, Chinese officials announced the virus can now be spread via aerosol transmission.
People with coronavirus can generate infectious aerosols - little droplets containing the virus - just by breathing.
These can drift through the air for an extended period of time and cause infection if breathed in.
"Aerosol transmission refers to the mixing of the virus with droplets in the air to form aerosols which cause infection after inhalation," Shanghai Civil Affairs Bureau deputy head Zeng Qun was quoted as saying by China Daily.
"As such we have called on the public to raise their awareness of the prevention and control of the disease."
Direct transmission occurs when people breath in air close to an infected patient who sneezes or coughs.
"When someone who is infected with a respiratory disease, like 2019-nCoV, coughs or sneezes they project small droplets containing the virus," the World Health Organisation warns.
"If you are too close, you can breathe in the virus."
Contact transmission often occurs when someone with the virus sneezes or coughs into their hands. They then contaminate objects that they touch - and when other people touch that contaminated surface they also get infected.
"Hands touch many surfaces which can be contaminated with the virus. If you touch your eyes, nose or mouth with your contaminated hands, you can transfer the virus from the surface to yourself," WHO warns.
How to protect yourself
The World Health Organisation warns the public should take basic protective measures against the new coronavirus.
Wash your hands frequently
Wash your hands frequently with soap and water or use an alcohol-based hand rub to eliminates the virus if it is on your hands.
Practice respiratory hygiene
When coughing and sneezing, cover your mouth and nose and either throw away the tissue or wash your hands afterwards to prevent the spread of germs and viruses.
Maintain social distancing
Maintain at least 1-metre distance between yourself and other people, particularly those who are coughing, sneezing and have a fever, to avoid being infected.
Avoid touching your eyes, nose and mouth
If you have the virus on your hands, this can spread into your body through your eyes, nose and mouth
People should self-isolate and seek medical attention if they are unwell
The Ministry of Health advises people should self-isolate for 14 days if they've travelled from or through China, or if they've specifically visited Wuhan or Hubei province.
Any travellers arriving in New Zealand who become sick within a month of their arrival are urged to seek medical advice and contact Healthline on 0800 611 116 or see a doctor.
"It is important to mention recent travel to Wuhan and any known contact with someone with severe acute respiratory illness who has been in Wuhan," the ministry says on its website.