The numbers make headlines every day: 43,000 people sickened by the novel coronavirus traced to Wuhan, China; a death toll over 1,000. But as the outbreak continues, another number is on the rise: those who’ve recovered.
Over 4,000 people have overcome the virus, according to data compiled by Johns Hopkins’ Center for Systems Science and Engineering. The majority of recovered cases are in China, where the majority of cases are occurring.
Other recoveries include the 35-year-old man in Washington state who became the first coronavirus case in the U.S., and seven people in Singapore.
As the nature of the crisis evolves, new, pressing questions are emerging, like, can those who’ve recovered get coronavirus again?
Nearly two weeks after the World Health Organization declared the coronavirus a global health emergency, Fortune posed that big question and four others to experts to better understand the concerning outbreak that’s captured the world’s attention.
1. How does the coronavirus spread?
The main route of infection is droplets expelled in the coughs and sneezes of an infected person. Any surfaces and objects that the droplets fall on will be contaminated, which is why experts recommend you sneeze into your elbow, not your hands.
“That’s how it passes—when someone else comes into contact with the contaminated objects or through handshakes, and then accidentally touches their nose or mouth,” said Eng Eong Ooi, a professor of emerging infectious diseases at Singapore’s Duke-NUS Medical School.
Ooi said that theoretically the coronavirus could spread through airborne aerosols, but so far its spread is “very unlike an airborne transmission” like the measles, a far more infectious virus that can travel hundreds of feet through the air.
2. What are the best ways to avoid it?
Consistent hand-washing, above all else, is the best way to avoid catching and spreading the virus. Hand sanitizer is fine, Ooi said, but regular hand-washing with soap and water is paramount.
“Between the two I would still say hand-washing is better because you literally wash the virus away; you’re not relying on something else to kill the virus,” Ooi said.
Ooi added that surgical face masks—which have seen global shortages in recent weeks—are designed for doctors and nurses to wear during surgical procedures, not to protect the wearer out in public day-to-day.
“Hand hygiene is a lot more efficient in preventing the spread,” Ooi said. “If anything, masks would lull the wearer into complacency and forget all about the more important things that they can do to prevent infection.”
Even if a mask did shield a wearer from coming into contact with infected droplets, then the person would need to be very careful taking off the mask to avoid touching the infected surface, and then immediately wash their hands.
3. If you catch the coronavirus and recover, can you get it again?
Based on existing knowledge of the body’s immune response to infection, individuals who recover should be protected against re-infection “definitely in the short-term, likely also in the long-term, and possibly for life,” said Ooi.
Though officials from China’s National Health Commission said it is “possible” for individuals sickened by the coronavirus to contract the illness a second time, because scientists do not know how long the antibodies produced to fight the infection will last, according to a news report from Chinese state media outlet CGTN. Officials encouraged recovered individuals to remain vigilant about their hygiene and health.
The question Ooi wants to explore is whether any post-infection immunity from the novel coronavirus will protect individuals from other animal-borne viruses—like this coronavirus and SARS before it—in the future.
“Will this new coronavirus prevent another SARS-like outbreak in the future?” Ooi said. “That we don’t know, and that will require a lot of research to answer the question.”
Ooi added that once the coronavirus is under control and the infection risk recedes, there will be a continued impact on recovered patients, especially people deemed “super spreaders.” Ooi encouraged compassion towards such individuals.
“They’ve been isolated for so long, and even when they’re discharged, if people stigmatize them and stay away from them…how would that label ‘super spreader’ affect their psychological well-being?” Ooi said.
4. How should businesses respond?
Spain has just two confirmed cases of the coronavirus, but Amazon, Ericsson, LG, ZTE, and NVIDIA have all pulled out of the Mobile World Congress, the high-profile tech show held this year in Barcelona, due to coronavirus-related concerns.
MWC organizers are banning visitors from Hubei province, where the outbreak originated, and has told attendees of the networking meetup to forgo handshakes.
Conferences and events across Asia, from Art Basel Hong Kong to a United Nations biodiversity conference, have been postponed, cancelled, or moved out of China over worries about the coronavirus.
In assessing coronavirus risks, public health officials and businesses should do what likely comes naturally: conduct cost-benefit analyses to the situation, said Ooi. “Everything we’re doing right now is literally with that goal in mind,” he said.
Companies have to consider whether employees working from home will affect productivity, or if the risk of the virus spreading is high enough to cancel an important conference.
“There’s a cost to everything and sometimes the cost is much more than the benefit you can derive from not having that meeting,” Ooi said. “In that instance, by all means you should go ahead, but where possible I think avoiding congregations of large numbers of people would be a good idea at this time.”
Millions of white-collar workers in China and all government employees in Hong Kong are working from home in an effort to halt the spread of the virus.
Eugene Hung, a molecular virologist at the Hong Kong University of Science and Technology, said working from home is an effective policy because it minimizes contact with other people, and the virus spreads through close contact with infected individuals.
“It makes sense to play safe,” Hung said.
Hung added that given the fatality rate of the disease, which is much lower than that of SARS, and the fact that the spread of the virus is “not out of control in places other than Hubei,” there is no reason for people to be “overly scared,” provided public health officials “deal with it carefully.”
“I have to say, the chance of catching the disease in Hong Kong is lower than the chance of winning the second prize in Mark Six,” said Hung, referring to a popular lottery in Hong Kong. The special administrative region has reported 42 cases of the coronavirus and one death.
5. How long will it last?
“Bringing this outbreak under control is going to require a global effort,” Ooi said.
Vaccines and symptom-reducing drugs are in the pipeline in various countries, but they will take time. Even if drug development is fast-tracked to bypass the standard regulations, which can take years to bring a drug from the lab to the clinic, “[i]t’s not something that we should expect in the next few months,” Ooi said.
“Forecasting epidemics is a little bit like trying to forecast the stock market—you’ll probably get it wrong most of the time,” Ooi said. “The best thing is to do whatever we can, focus our attention on whatever we can to prevent spreading the virus.”
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—Why China is still so susceptible to disease outbreaks
—A new coronavirus red flag on the horizon—a stronger dollar
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