What started as a mystery virus last month in Wuhan, China, has now killed at least 17 people and infected hundreds more around the world.

In the US, the first case of Wuhan coronavirus was confirmed Tuesday in Washington state -- stoking fears of an outbreak in this country.

So what are officials doing in the US, and how can you minimize your risk?

What airports are doing?

Passengers from Wuhan to the United States -- either on direct or indirect flights -- will soon only be allowed to land at one of the five US airports.

Three of those US airports -- John F. Kennedy International Airport in New York, Los Angeles International Airport and San Francisco International Airport -- are already checking those incoming passengers for symptoms such as fever, cough and trouble breathing.

By the end of this week, two more airports will screen passengers -- Hartsfield-Jackson Atlanta International Airport and Chicago O'Hare International Airport.

But these airport screenings might not catch everyone infected. That's because the incubation period can last a week -- meaning it can take a week after getting infected before showing any。

What scientists are doing

Across the US, scientists are trying to create a vaccine for the new virus. But don't expect it anytime soon.

The National Institutes of Health is working on one, but it will take at least a few months before clinical trials start and more than a year until a vaccine might actually become available.

Separately, scientists in Texas, New York and China are also trying to create on a vaccine, Dr. Peter Hotez, a vaccine scientist at Baylor College of Medicine in Houston.

But the challenge is daunting.

"The lesson we've learned is coronavirus infections are serious and one of the newest and biggest global health threats,"

What you can do yourself

Avoid close contact with anyone showing symptoms of respiratory illness, such as coughing and sneezing, the World Health Organization says.

Other symptoms of this coronavirus include fever and shortness of breath. Severe cases can lead to pneumonia, kidney failure and even death.

Scientists believe this coronavirus started in another animal and then spread to humans. Health officials recommend cooking meat and eggs thoroughly and washing your hands often with soap and water for at least 20 seconds.

If you're the one feeling sick, cover your mouth and nose when you cough or sneeze, and disinfect the objects and surfaces you touch.

If you or your doctor suspect you might have the Wuhan coronavirus, the Centers for Disease Control and Prevention advises wearing a surgical mask.

What could happen next?

The World Health Organization is having an emergency meeting Wednesday to decide whether any global recommendations should be made.

Such recommendations could include cross-border screening, increased surveillance or even quarantine measures for those affected, similar to quarantine rules already in place in China.

We’ve had weather forecasts for decades. Forecasting our near-term health is far tougher. Yet knowing early that we may be coming down with the flu or COVID-19 could be hugely helpful. The good news: Wearable technology, such as smartwatches, is beginning to provide just such early warnings. This early warning can help stop infections in the bud. It may head off severe symptoms that otherwise would send vulnerable (易受伤害的) people into hospitals.

Jessilyn Dunn was part of a team that analyzed data from wearable devices. The smartwatch-like systems contain sensors. These collect data that can point to health or disease.

The researchers gave 31 of the 49 recruits (成员们) nose drops with a flu virus. Trials where volunteers agree to receive a virus are unusual. They also can be dangerous. So the researchers made sure the volunteers were healthy and would not give the flu to others. Recruits started wearing the wristbands before they were exposed. The sensors continued to collect data for several days after the exposure. Some data were measured more than 30 times per second. That means the 49 recruits had up to 19 million data points each. Dunn tested its predictions in the remainder of the data. Her final model accurately predicted infections 9 times in every 10.

One challenge for the study is that many viral infections have similar symptoms. In fact, many things other than viruses trigger (引起) the same symptoms. What’s more, in real life, we don’t know who was exposed to some viruses and when.

Could such a system one day point to people coming down with COVID-19? Maybe, says Dunn. Similar technologies are being developed elsewhere to provide early warnings of that infection.

“Such studies sound exciting, but also very pilot,” Dunn says. “95 percent of prediction accuracy sounds good. But that number means telling one out of every 20 people every night that they will get the flu when they actually won’t.”

At some point in life, many people develop a mental problem. While most people get over it, for others it doesn’t go away easily.

The WHO says that about 20 percent of teenagers worldwide suffer from mental illness. It’s thought that the number of teenagers with mental illness around the world will increase by half by 2022. It will become one of the main causes of illness, and even death.

In China, the picture isn’t bright, either. About one tenth of teenagers under the age of 17 have a mental health challenge.

The world is changing fast. Study and relationships have always caused stress, but today the stress is much higher than before, the WHO said.

A research centre in Oxford University says that young people today have big stresses at school. For example, they experience bullying. In a 2017 report, the centre noted that the Internet was a special source of stress. Online, young people often see “messages about perfection” and this causes the young “great uncertainty about their futures”, says the centre.

Also, according to China Daily, Chinese people don’t ask for help with their mental problems. They fear that others will think less of them if they say that they are in mental trouble. Elaine Peng, a US mental health educator, makes a similar point. And in the UK, over three quarters of young people believe their mental problems have a social stigma. It is reported in 2017 that a quarter of young UK people wouldn’t ask for help if they developed a mental problem.

Young people who don’t ask for help for their condition may be creating problems for themselves in the future. Elaine Peng warned that, “If we hide our mental health, it may remain a problem forever.”

“My message for young people is, if you feel something is wrong within you—ask for help,” he told China Daily.