By Agence France-Presse
For WHO chief Tedros Adhanom Ghebreyesus, the key question in the battle against the novel coronavirus is how quickly it is spreading beyond China.
Pedestrians wear face masks, as a preventative measure against the COVID-19 coronavirus, as they walk on a footbridge in Hong Kong on February 12, 2020. - The virus, officially named COVID-19, has spooked markets around the world, having killed more than 1,100 people and infected tens of thousands since it emerged in central China at the end of last year. (Photo by Anthony WALLACE / AFP / MANILA BULLETIN)
"The detection of a small number of cases may indicate more widespread transmission in other countries; in short, we may only be seeing the tip of the iceberg," he warned in a recent tweet.
Here are some of the key issues:
How the virus transmits
It is a respiratory virus, spreading through contact with an infected person: their coughs, sneezes or droplets of saliva or discharge from the nose.
Scientists think a person needs to be within a meter of an infected person to risk catching it.
Health officials stress basic precautionary measures: washing hands frequently, covering up coughing or sneezing. And if you are infected, wear a mask to protect others.
Diarrhea may be a secondary mode of transmission, according to one team of researchers.
And Chinese scientists writing in the New England Journal of Medicine suggested every person infected would, on average, infect another 2.2 individuals.
That is a higher rate than winter flu (1.3), lower than an infectious disease such as measles (more than 12) and comparable to SARS (3) -- the last major virus that broke out in China, in 2002-03.
When it becomes contagious
Scientists initially thought the virus became contagious several days after symptoms started to appear, as happened with SARS, Arnaud Fontanet of the Institut Pasteur told AFP.
They now think it could be infectious earlier than that.
"Today, everybody agrees that the contagious period starts as soon as symptoms appear," said Fontanet, a specialist in tracking emerging diseases.
There had even been a few cases of transmission from people who showed no symptoms, he added.
One reason these cases are rare is that coughing is a major means of transmission -- and a symptomless carrier does not cough.
Even so, transmission by symptomless carriers makes it harder to contain the virus because they are harder to spot.
Spread outside China
The concern expressed by Ghebreyesus about the spread of the virus beyond China came as news broke of a British national infected in Singapore.
He went on to infect several other Britons during a stay at a French Alpine ski resort, before finally being diagnosed back home in England.
By then, he had infected at least 11 people, including a nine-year-old child.
"What is concerning is the source of these infections, which appears to have been a conference in Singapore attended by some participants from China," said Nathalie MacDermott of Imperial College London.
Some of the 90 other people there might also have taken the virus back to their home countries, said MacDermott, a specialist in pediatric infectious diseases.
Every time health officials identify an infected person, they have to track down those they might have infected to ensure they, in turn, are not passing it on, she said.
She and other experts are already worried about "the potential for this epidemic to develop into a pandemic."
Catching it in hospital
On Friday, Chinese researchers published a study of 138 coronavirus patients at a hospital in Wuhan, the epicenter of the outbreak.
In their paper, published in the Journal of the American Medical Association, they noted that more than 40 percent of these patients -- 57 -- caught it in hospital.
Seventeen were already in hospital for other reasons and the other 40 were health professionals.
This was already a problem during the outbreak of SARS and the Middle East Respiratory Syndrome coronavirus (MERS), two other deadly outbreaks featuring different types of coronavirus.
That makes treating patients not infected all the more difficult, said Fontanet.
Ridding a hospital of coronavirus when it has this kind of transmission is "extremely difficult," he added.
Overworked, unprotected
Doctors on the frontline of China's new coronavirus epidemic are facing a daunting task: treat an ever-growing number of infected patients and risk getting infected themselves due to a drastic shortage of masks and other protective equipment.
Tired and understaffed, medical workers have had to deal with thousands of new cases per week in Wuhan.
Many doctors have had to see patients without proper masks or protective body suits, resorting to reusing the same equipment when they should be changed regularly.
Some have even worn diapers to avoid having to take off the equipment and make it last longer, according to a health official.
One doctor at a community clinic in Wuhan said he and at least 16 other colleagues were showing symptoms similar to the new virus, including lung infections and coughing.
"As doctors, we do not want to work while being a source of infection," he told AFP, requesting anonymity for fear of reprisals.
But "right now, there is no one to replace you," the doctor explained, adding that all medical staff without a fever are expected to work.
"What would happen if there was no one working on the frontline?"
Some 44 percent of the 42,600 cases nationwide -- and the majority of more than 1,100 deaths -- have been in Wuhan, home to a wild animal market where the virus is suspected of having originated before spreading between humans.
The risks medical staff are facing was highlighted on Friday after Li Wenliang, a whistleblowing doctor in Wuhan, succumbed to the disease more than a month after he first raised alarm about a new SARS-like virus in the city.
His death unleashed an outpouring of grief and anger on Chinese social media, with 10 academics in Wuhan circulating an open letter calling for political reform and freedom of speech.
Mask deficit
The deputy mayor of Wuhan said the city is facing a daily shortage of 56,000 N95 masks and 41,000 protective suits.
Medical staff in protective suits will "wear diapers, reduce how much water they drink, and reduce how many times they use the bathroom," said Jiao Yahui, a top official at China's National Health Commission.
Some of them will wear the same protective suit for six or even nine hours, when they should not be worn for more than four hours in a quarantined ward, she said last week.
"Of course, we don't advocate this method, but medical staff really have no alternative," she admitted.
The Chinese government has responded by mobilizing the entire country to increase the production of masks and suits. China has also imported more than 300 million masks and about 3.9 million articles of protective clothing since January 24, an official said last week.
The Red Cross Society of China too has received over 900 million yuan ($129 million) in donations for epidemic relief -- though it has drawn scrutiny for its lack of transparency and efficiency.
"Even if we receive more masks, the number of patients increases even faster," said a doctor at a major Wuhan hospital, who requested anonymity because she was not authorized to speak with media.
"The consumption of masks in the hospital is enormous," she emphasized. "They have a permanent lack of masks."
Calls for help
Handling the daily deluge of new cases takes another kind of toll too, said the doctor at the large hospital in Wuhan, whose colleagues are handling confirmed cases of virus patients.
"They are exhausted," she told AFP. One of her colleagues, for instance, works at a clinic that receives 400 patients within eight hours.
Many are dealing with patients "who die very quickly, whom they have not managed to save," she said.
"They have a lot of pressure," the doctor said, adding that her hospital had set up psychological monitoring.
Many Wuhan residents are worried, too, said the doctor at the community clinic.
He and his colleagues receive calls from distressed community members, he said -- some of whom are too afraid to leave their homes.
"You can hear their calls for help, but your hands are tied," the doctor said, describing families where patients are stuck at home without medical treatment. "There's nothing we can do."
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