What is needed to control this pandemic?
A vaccine would be our greatest weapon against the coronavirus pandemic that is sweeping across the world.
No vaccine currently exists, because this is a new virus.
The global scientific community is locked in a race to develop one but experts at the World Health Organisation say it will take 12 to 18 months.
The number of diagnosed cases of Covid-19 worldwide topped 350,000 yesterday. With that figure expected to soar in the coming weeks, the predicted timeline for the development of a vaccine is concerning.
But there are a few important things to consider.
Why will it take so long?
Dr Maire Connolly, Adjunct Professor of Global Health and Development in Discipline of Bacteriology, School of Medicine at NUI Galway, explains: "People need to understand that the development of a vaccine is a hugely complex endeavour, primarily to ensure the safety of each vaccine.
"Vaccines have got to work and be safe. Initial studies have to be carried out on animal models before they are tested on people in clinical trials.
"And it is a brand new virus. It is quite similar to Sars Cov-1 that occurred in 2003 but the vaccine developed took 20 months to be ready for testing in humans."
The outbreak was under control at this point so the vaccine was not used.
"We were very lucky during Sars because people were not infectious until they were six days into the illness, which made it so much easier to identify people, isolate them and identify contacts.
"That outbreak was stopped at about 8,000 cases and 800 dead. Some of this work can be built on but Sars Cov-2 is still a new virus."
Professor Connolly drew a comparison with the annual flu vaccine, which is adapted every year to counter different emerging strains.
"With the flu vaccine, we already have a model we build on. Every year, the strains of flu change, but we already have the vaccine platform and you can adapt it. That's why the pandemic vaccine was developed in record time in 2009.
"Whereas here we have a brand new virus."
What can we do now?
Professor Connolly said there were measures we could take until a vaccine is rolled out.
"This virus will circulate until a high proportion of the population become immune to it so the priority is that inevitability.
"What really is crucial is to reinforce the message to people that we can control this disease by self- protection and prevention of transmission of infection to others while we wait for the development of a vaccine."
What has been done already?
In terms of important research, Australian scientists have mapped the immune responses from one of the first coronavirus patients.
This is a vital step in developing a vaccine and treatment.
While most people infected experience only mild symptoms, up to 20pc of patients will develop severe or critical illness.
Scientists at Australia's Peter Doherty Institute for Infection and Immunity examined the blood results from a woman in her 40s who returned from Wuhan to Australia.
They discovered that a person's immune response to coronavirus acts in the same way as the flu.
As researchers monitored her immune response, they were able to accurately predict when she would recover.
The findings helped scientists understand why some patients develop mild symptoms and recover while others develop more serious respiratory problems.
The first human trial on a vaccine began in the US last week, the National Institute of Allergy and Infectious Diseases announced.
Scientists will first test whether the vaccine is safe and later programmes will determine how well it works.
The trial was "launched in record speed", Dr Anthony Fauci, the institute's director, said in a statement.
The rapid development of a potential vaccine is unprecedented, and it was possible because researchers were able to use what they already knew about related coronaviruses such as Sars and Mers. However, if the vaccine is proved safe and effective against the virus, it will still take at least a year to roll out.
China has also approved the start of a vaccine clinical trial that has been developed by researchers led by a biowarfare expert Chen Wei of the Academy of Military Medical Sciences in Wuhan.
She said: "We are a community of shared future for mankind, and the vaccine is one of the most powerful scientific and technological weapons to end the novel coronavirus epidemic."