The death toll from a new virus that has swept the Middle East and Europe has now fallen to 28 but the disease remains highly contagious and death rates remain high.
New cases have now fallen below the 60 daily average set in December, but epidemiologists warn that unless levels are consistently lowered, the infection remains a live threat to public health.
An outbreak of coronavirus in Saudi Arabia is no longer considered the likely source of the virus, and the US Centers for Disease Control and Prevention (CDC) said on Friday that it was removing its infection from its list of “emerging infectious diseases”.
New cases of the virus, formally known as NCoV, are falling for two reasons: non-immune infected people have died, and the disease’s high fatality rate means that while almost half of those infected have survived, the vast majority are still sick.
“The real question is will the outbreak die down?” said Paul Aseltine, a vaccine researcher at Columbia University. “Our definition of outbreak hasn’t changed since the first case was reported. That does not mean that it can’t start again.”
Research suggests that there is a very low risk of the virus setting off a major global pandemic, but the World Health Organisation (WHO) is reporting that the rate of the spread of coronavirus out of Saudi Arabia into the rest of the Middle East and Europe has slowed markedly.
Muhannad Al Sali of the WHO’s Geneva headquarters said: “The prevalence of infection appears to be stabilising in the countries of concern, where there have been over 2,000 reported cases.
“The slow rate of global spread, together with most acute illness occurring outside hospitals, is increasingly making it a low-probability event of international spread of NCoV, and [we are] closing the last transition zone on our current report.”
On Friday, the WHO lifted its immediate travel warning to Lebanon, while UK civil defence raised its pandemic alert to phase 1 – the highest level – but all further alerts remain at phase 2, which signifies the likelihood of a pandemic, despite the likelihood that a peak in cases has passed.
Sir Mike Rawlins, the chief executive of the UK’s health regulator, said in January that authorities would need to be ready if the virus broke out, but that predicted surges in cases may not materialise.
Meanwhile, the US health authority is hoping to get approval from the European Medicines Agency for a possible haemodialysis treatment for coronavirus sufferers, including nine Britons who have fallen ill.
Esograft Rössl, from the firm Pfizer, said the so-called “wash-away” pills would be most effective in the most severe cases.
The situation in the west, however, is different. In the UK, a previous extension to the cleaning regime at hospitals used to reduce the chance of catching infection has put the community back on alert.
Samples tested for MERS-CoV found “serious possibilities” from the first batch of tests, but the blood samples proved negative. The new samples, paid for by the Public Health England, will now be used to test for further natural and genetic mutations to the virus.
Britain’s department of health said that the NHS would continue to take a cautious approach to reporting.
“NHS Scotland and Public Health England have analysed fresh samples and confirmed that testing has been negative for any activity that may be associated with the recent MERS-CoV outbreak,” it said.
“Although there are new samples being collected, they are being sequenced to identify the organisms and require further analysis.”
There have been a number of scientific studies over the past week which found that the coronavirus is likely to be related to similar viruses that led to the deaths of thousands of people in the Middle East and Europe last year.
The WHO has predicted a 50% rise in MERS-CoV cases this year, putting it on a par with the annual peak of the 2012/13 H1N1 flu pandemic.