What you need to know about the coronavirus right now

HERE'S what you need to know about the coronavirus right now:

WHO team didn't get all the data during China probe, Tedros says

Data was withheld from World Health Organization investigators who travelled to China in January and February to research the origins of the coronavirus epidemic, WHO Director-General Tedros Adhanom Ghebreyesus said on Tuesday.

Although the team concluded that a leak from a Wuhan laboratory was the least likely hypothesis for the virus that causes COVID-19, Tedros said the issue required further investigation, potentially with more missions to China.

"I do not believe that this assessment was extensive enough," he told member states in remarks released by the WHO. "Further data and studies will be needed to reach more robust conclusions."

Chinese city on Myanmar border orders home quarantine over new COVID cases

The southwestern Chinese city of Ruili that borders Myanmar ordered on Wednesday a one week home quarantine for residents of the city's urban area, and mass COVID testing, after reporting six new locally transmitted coronavirus cases.

Health authorities in Yunnan province, where Ruili is located, said the six new cases were Chinese citizens, while three asymptomatic patients, who are infected with the coronavirus but show no symptoms, were Myanmar citizens.

Ruili on Wednesday will crack down on illegal border crossings, according to a statement from the city government published by the Communist Party authorities of Yunnan province. The city will only allow individuals with a negative nucleic acid COVID-19 test within 72 hours to leave Ruili and will advise all people and vehicles coming to the city to turn back.

23 countries back idea of pandemic treaty

Leaders of 23 countries and the WHO on Tuesday backed drawing up an international treaty that would help deal with future health emergencies like the coronavirus pandemic by tightening rules on sharing information.

The idea of such a treaty, also aimed at ensuring universal and equitable access to vaccines, medicines and diagnostics for pandemics, was floated by the chairman of European Union leaders, Charles Michel, last November.

The leaders of China and the United States did not sign the treaty proposal, but Tedros said both powers had reacted positively to it, and all states would be represented in talks.

T cells induced by COVID-19 infection respond to new virus variants

A critical component of the immune system known as T cells that respond to fight infection from the original version of the novel coronavirus appear to also protect against three of the most concerning new virus variants, according to a U.S. laboratory study released on Tuesday.

Several recent studies have shown that certain variants of the novel coronavirus can undermine immune protection from antibodies and vaccines. But researchers analysing blood from 30 people who had recovered from COVID-19 before the emergence of the new, more contagious variants found the T-cell responses remained largely intact and could recognise virtually all mutations in the variants studied.

The findings add to a prior study that also suggested T cell protection appears to remain intact against the variants.

Germany limits use of AstraZeneca COVID shots

Germany will from Wednesday limit the use of AstraZeneca's AZN.L COVID-19 vaccine to people aged 60 and above as well as high-priority groups following further reports of a rare brain blood disorder.

"We have to be able trust the vaccines," Chancellor Angela Merkel told journalists at a news conference on Tuesday. "And transparency is the best way to deal with such a situation," she added.

People aged below 60 who have already received a first AstraZeneca shot have the option of either receiving their second shot as planned, if they are high priority, or to wait for STIKO to issue its recommendation, which it is expected to do by the end of April.