The US government has asked Beijing for permission to send a team of experts from the Centres for Disease Control and Prevention (CDC) to work with domestic health workers on the front lines of the Wuhan coronavirus outbreak there.
It has also asked Beijing for more data on confirmed cases in China, as health authorities around the world work to contain the spread of the illness.
In a Washington news conference on Tuesday about the US response to the outbreak, Health and Human Services Secretary Alex Azar said his department was waiting for a response from the Chinese government to the request to form a bilateral team, or to accept a team of US experts working under the authority of the World Health Organisation.
Azar said that he had personally extended “the offer … which we do hope that the Chinese government will take us up on that CDC experts are standing by ready, willing, able to go immediately to China either on a bilateral basis or under the auspices of the World Health Organisation”.
Concerning information about the transmission of the disease, CDC Director Robert Redfield said that the agency in particular seeks data on cases caused by contact with individuals who did not present any signs of the illness, which could provide key insights into how the disease is spread and how dangerous it is.
“The Chinese have reported evidence of transmission in the asymptomatic phase, based on data that they have reviewed. The CDC has not been given an opportunity to review that data,” Redfield said. “What we say is that we have not been able to confirm by data the impact of transmission during the asymptomatic phase.
“The Chinese believe they have that data, so our hope is that we could get directly involved in China to be able to review and be more definitive.”
Currently 110 people are being evaluated in the United States for infection, with five confirmed cases.
But the total number of confirmed cases has climbed to more than 4,500 in China alone, with 106 deaths – 26 new deaths reported in the country on Tuesday. Most of those who have died were from Hubei province, at the epicentre of the outbreak.
Hubei’s capital, Wuhan, which was put under a travel ban last week, is a major high-speed rail and air transit hub.
Working in the most heavily infected areas of China would help the CDC speed its development of possible treatments and a vaccine for the new coronavirus, said Anthony Fauci, director of the US National Institute of Allergy and Infectious Diseases.
“There is no proven therapy for coronavirus infection,” Fauci said, adding that having more isolates of the new virus would help build on progress health authorities had made in using antiretroviral medication to treat cases of severe acute respiratory syndrome (Sars), which caused nearly 800 deaths in 17 countries in 2002-2003.
More isolates would also help in the development of monoclonal antibodies as a possible cure for the Hubei coronavirus, Fauci said.
“When we were dealing with Sars, we developed monoclonal antibodies as potential therapeutics,” he explained. “No proven therapy because they were not used. They were only used in in-vitro and animal models. Given the somewhat close homology between Sars and the new novel coronavirus, there could be some cross reactivity there that could be utilised.”
Meanwhile, the CDC expects to have a vaccine in a “phase-one” trial within the next three months, based on isolates taken from the five cases confirmed in the US, Fauci added.
Also attending the news conference was Nancy Messonnier, director of the CDC’s National Centre for Immunisation and Respiratory Diseases, who said that screening for signs of illness among passengers returning to the US from Wuhan is being expanded from five international airports – in New York, Chicago, Atlanta, San Francisco and Los Angeles – to 20.
In addition to air transmission, the coronavirus can be spread through physical contact, China’s National Health Commission (NHC) said on Tuesday.
The incubation period of the new virus is on average three to seven days, with the longest being no more than 14 days, the NHC stated, adding that the coronavirus strain was 85 per cent similar to Sars).
A risk assessment report based on analysis of 2,744 infections recorded up to Sunday by the Chinese Centre for Disease Control and Prevention, released on Monday, found that the main route of transmission was respiratory droplets and close physical contact.
“The virus is highly contagious, with a reproduction number [the average number of cases each case generates during the infectious period] of between two and three,” the report said.
That virulence prompted authorities in China last week to institute a travel ban for Wuhan and most other cities in Hubei province.
Responding to the ban, the US State Department has arranged for a flight on Wednesday to transport American consular staff and private citizens from Wuhan to Los Angeles.
“We will be heavily engaged with that flight and the transport of those individuals,” Azar said. “They will be screened and evaluated constantly. There will be physicians on the flight, and we’ll take whatever the appropriate evidence-based public health measures are with them as we would in any other situation.