Wuhan virus: Current estimate is 20% of patients will become severely ill, says Singapore infectious diseases expert

People are seen wearing masks as they walk down Orchard Road on Jan 26, 2020. ST PHOTO: KELLY HUI

SINGAPORE - An estimated 20 per cent of the people infected with the Wuhan virus will become very ill, such as with more severe pneumonia, says a Singapore infectious diseases expert.

That is the current estimate and this may change when more is known about the Wuhan coronavirus, also known as the 2019-novel coronavirus (2019-nCoV), says Dr Shawn Vasoo, the acting clinical director at the National Centre for Infectious Diseases (NCID).

There are currently four confirmed cases of the 2019-novel coronavirus in Singapore. The patients had all travelled from China where the virus is spreading fast.

With concerns growing, The Straits Times asked Dr Vasoo to explain what else is known about the virus that has so far reportedly killed more than 50 people in China.

Q: Why does the virus lead to pneumonia and will everyone get it?

A: In some people, the virus infects the lower respiratory tract (lungs) and this results in pneumonia. Not everyone will get pneumonia but in most diagnosed cases so far, pneumonia, of varying severities, has been commonly described.

Q: How do I get cured of pneumonia? Is pneumonia the worst that can happen to me if I get the virus?

A: As there are currently no proven specific anti-viral medications for the 2019-novel coronavirus, one overcomes the infection with our immune system, and recovers thereafter.

Not all cases of pneumonia are severe, but most patients who have fared poorly are those who have gone on to develop severe pneumonia.

Severe cases may have more concurrent chronic medical problems such as cardiovascular disease or lung disease.

Currently, an estimated 20 per cent of the people infected with the 2019-novel coronavirus will become very ill (more severe pneumonia). However, this estimate may change as we learn more about this disease.

Q: What are the symptoms of the Wuhan virus?

A: The common symptoms include fever, cough, in more severe cases, shortness of breath, especially when there is pneumonia. Occasionally some symptoms may be absent, for example fever.

Q: How do I know if the coughing, fever and other respiratory symptoms that I have is the common cold, flu, dengue or the Wuhan virus?

A: It is not possible to distinguish clearly between the common cold, influenza and the 2019-novel coronavirus.

Even influenza, which is more common, can lead to severe disease and pneumonia. It also causes death.

However, unlike in Wuhan, there is currently no widespread community transmission in Singapore.

Hence, we would be concerned about a possible 2019-novel coronavirus infection only if one has travelled to China or if one has been in contact with a known case of the infection.

As for dengue, respiratory symptoms are less common and fever, rash, muscle aches and headaches are more common.

Q: When should I go to a general practitioner (GP)?

A: You should seek medical attention if you are not feeling well in general, particularly if symptoms have not improved in two to three days. You should seek immediate medical attention if you have risk factors for the 2019-novel coronavirus as described above, so your doctor can assess you.

Q: If I have symptoms, should I go straight to the NCID or a hospital?

A: If you have symptoms you can see your family doctor or polyclinic who will make the initial assessment.

If more urgent medical attention is needed, or if it is a medical emergency, you should seek medical attention at the nearest emergency clinic or hospital.

Q: What is the best way to not catch the Wuhan virus?

A: Avoid travelling to affected areas, in particular the Hubei province. If you are travelling to China, you should exercise caution and observe good hand hygiene (hand washing or use of hand sanitisers) and avoid crowded places.

A photo of a man with a mask on at Plaza Singapura MRT on Jan 26, 2020. ST PHOTO: KELLY HUI

Q: What does wearing a mask do?

A: As infection by the 2019-novel coronavirus and other common respiratory viruses are spread by respiratory droplets carrying the virus, surgical masks can prevent inhalation of these droplets.

You should wear a surgical mask if you are ill to prevent spreading whatever respiratory virus you have to others (this is most commonly influenza and the common cold viruses). This is part of being civic conscious.

Surgical masks may help prevent infection from respiratory viruses in general, if one is around sick people.

Those who are more prone to infection, such as the elderly or those with poor immune systems, would want to consider wearing them.

I would discourage the routine use of N95 masks as mask fitting is typically required for its proper use.

It is also more stuffy and uncomfortable if used for prolonged periods, and may actually be less effective than a surgical mask if used improperly.

There is no known transmission of the 2019-novel coronavirus in the community in Singapore at this point, so the routine use of a mask to prevent this particular infection is probably unnecessary.

However, If you are going to an affected area, you should strongly consider the use of a surgical face mask.

Q: If I were in contact with someone who has the Wuhan virus and am infected, how long would it take for the symptoms in me to show?

A: This may vary, as patients have developed symptoms as early as in two days while others may develop symptoms later, for example in 10 to 14 days. The average is estimated to be about one week.

Q: At which stage am I most likely to infect other people?

A: You are most likely infectious when you have symptoms, in particular fever and cough.

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