Coronavirus incubation period in doubt as US patient recovers using experimental Ebola drug

Chinese county has increased its coronavirus quarantine period from 14 to 21 days after a patient took more than a month to show symptoms.

The 14-day incubation period for the deadly coronavirus has been thrown into doubt, with several patients in China taking more than a fortnight to show symptoms.

At least four provinces in China have reported cases of the COVID-19 virus taking longer than 14 days to confirm after transmission, according to the South China Morning Post.

One person in the central Henan province took 34 days to test positive after being exposed to the virus during a trip to Wuhan in mid-January, the Post said.

He was sent to hospital with suspected symptoms on January 28, but twice tested negative for the disease before testing positive on February 16.

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The local county government has now extended its imposed quarantine period from 14 to 21 days, with similar cases also reported in China’s southern Guangdong province and eastern Anhui and Shandong provinces.

But the World Health Organisation (WHO) last week said it was sticking to its recommended 14 days of isolation.

The outbreak of the novel virus began in China two months ago. Picture: Chinatopix via AP

The death toll has jumped to 1,770 in China after 105 more people died on Monday, according to the National Health Commission. Picture: STR/AFP

A recent study conducted by a team of Chinese scientists showed the virus’s incubation period could actually span up to 24 days.

Though Dr Michael Ryan, the executive director of the WHO’s health emergencies program, said those cases may have been outliers.

“We’ve seen this in Ebola. We’ve seen very long incubation periods and then when we investigate, we find that there was a second exposure a week later, or two weeks later, and that’s when the actual infection occurred,” he said in a press conference.

“There very often can be outliers, and they can be because of the recording of the exposure. We need to be really careful when we look at outlier figures.”

US PATIENT TREATED WITH EBOLA DRUG

More than 71,000 people have now been infected with the virus, which was first detected at a seafood market in Wuhan in December and at least 1,770 people have died.

Researchers across the world are hurriedly working towards developing a vaccine, though doctors in the United States have said they successfully treated a man with the experimental antiviral drug, remdesivir.

According to theSouth China Morning Post, a 35-year-old was given the drug at the Providence Regional Medical Centre in Washington after a lung X-ray showed he was developing pneumonia.

The next day his fever went away and he began feeling better.

Researchers are now racing to develop a vaccine for the coronavirus. Picture: GREG BAKER/AFP

“It is only one case,” Dr George Diaz, the hospital’s chief of infectious diseases, said.

“It’s the first person in the world who got this medication for novel coronavirus, but it seems to have worked.”

US biotech firm Gilead originally developed remdesivir as a treatment for Ebola, but it ultimately proved ineffective against that disease. The drug is now being used in two clinical trials in China.

AUSSIES PREPARE TO EVACUATE

The news comes as about 200 Australians stranded on a cruise ship in Japan are preparing to be evacuated.

The virus-hit Diamond Princess has been quarantined at the port of Yokohama for more than two weeks, with more than 450 cases confirmed on the ship, including at least 16 Australians.

But stranded Australian passengers have now been given the option to be evacuated to the unused Howard Springs workers site near Darwin on Wednesday.

There, they will have to undergo another two-week quarantine period.

“Given there has been recent cases, we cannot be absolutely sure that any of the currently-well people on the ship who are coming home on Wednesday are not carrying the virus,” Australia’s chief medical officer Brendan Murphy said.

“It’s frustrating and it’s unfortunate, but it is absolutely necessary to ensure that we put the measures in place that have been so effective in containing the spread of this virus,” Prime Minister Scott Morrison said.

There have been 15 cases of COVID-19 in Australia, with eight people now recovered and the rest in a stable condition.

– With wires