Coronavirus are a broad family of viruses, but only six (the new novel coronavirus makes it seven) are known to infect people.
On January 30th, the World Health Organization (WHO) declared the coronavirus outbreak a global health emergency – as it did with swine flu and Ebola. The organization’s director-general, Tedros Adhanom Ghebreyesus, said his main concern was that the outbreak could spread to countries with fragile health systems.
Declaring a “public health emergency of international concern” (PHEIC) is the WHO’s highest level of alarm — a step it reserves for events that pose a risk to multiple countries and that require a coordinated international response.
How severe are the symptoms?
It seems to start with a fever, followed by a dry cough and then, after a week, leads to shortness of breath and some patients needing hospital treatment.
Around one-in-four cases are thought to be severe.
Notably, the infection rarely seems to cause a runny nose or sneezing.
The earliest documented case has been traced back to 1 December.
The coronavirus family itself can cause symptoms ranging from a mild cold all the way through to death.
How easily does it spread between people?
At the beginning of the outbreak, the Chinese authorities said the virus was not spreading between people – but now, such cases have been identified.
Scientists have now revealed each infected person is passing the virus on to between 1.4 and 2.5 people.
This figure is called the virus’ basic reproduction number – anything higher than 1 means it’s self-sustaining.
We now know this is not a virus that will burn out on its own and disappear.
Only the decisions being made in China – including shutting down cities – can stop it spreading.
While those figures are early estimates, they put coronavirus in roughly the same league as Sars.
When are people infectious?
Chinese scientists have confirmed people are infectious even before their symptoms appear.
The time between infection and symptoms – known as the incubation period – lasts between one and 14 days.
Sars and Ebola are contagious only when symptoms appear. Such outbreaks are relatively easy to stop: identify and isolate people who are sick and monitor anyone they came into contact with.
Flu, however, is the most famous example of a virus that you spread before you even know you’re ill. It is common for lung infections to spread without symptoms.
What is not known is how infectious people with coronavirus are during the incubation period.
How can the virus be stopped?
There is also no vaccine to give people immunity to the virus. However, the work to develop them is already under way. It is hoped that research into developing a vaccine for Mers, which is also a coronavirus, will make this an easier job.
And hospitals are testing anti-viral drugs to see if they have an impact.
The only option is to prevent people who have become infected from spreading the virus to others.
- Limiting people’s movement
- Encouraging hand-washing
- Treating patients in isolation with healthcare workers wearing protective gear
A massive feat of detective work will also be needed to identify people whom patients have come into contact with to see if they have the virus.