What you need to know about the coronavirus right now

Here's what you need to know about the coronavirus right now:

New cluster in Australia's Melbourne expands to 10 cases Health authorities in Australia's Victoria state ramped up contact tracing and prepared for more mass testing of residents in Melbourne after a new COVID-19 cluster linked to a quarantine hotel grew to 10 cases on Thursday.

More than 22,500 test results were conducted in the past 24 hours in

Australia's second most populous city Melbourne and authorities urged residents to get tested amid fears of community transmission from a worker at the Holiday Inn in the city.

The latest outbreak was likely sparked by a medical device known as a nebuliser being used by a COVID-positive guest at the hotel.

Two masks, snug fit reduces COVID-19 spread, US study shows Making sure a mask fits snugly on the face and use of two masks is likely to significantly reduce a person's exposure to the coronavirus, US health officials on Wednesday said laboratory experiments showed.

The combination of a cloth mask over a three-ply medical procedure mask blocked 92.5% of the cough particles, the experiments conducted by the US Centers of Disease Control and Prevention (CDC) in January showed.

Re-useable devices known as mask-fitters were also an option to improve a mask's fit, CDC Director Rochelle Walensky told reporters.

Use AstraZeneca's COVID-19 shot, WHO panel says AstraZeneca COVID-19 vaccine is safe and effective and should be deployed widely, including in countries where the South African variant of the coronavirus may reduce its efficacy, a World Health Organization panel said on Wednesday.

In interim recommendations on the shot, the Strategic Advisory Group of Experts on Immunisation (SAGE) panel said the vaccine should be given in two doses with an interval of 8 to 12 weeks, and should also be used in people aged 65 and older.

"We have thousands of people dying from the infection, in many countries of the world, daily," Alejandro Cravioto, chair of the Strategic Advisory Group of Experts on Immunisation (SAGE) panel, said. "Anything we can do to use a product that might reduce that is totally justified."

Experimental drug may speed viral clearance An experimental antiviral drug significantly sped up the time it took to "clear" the virus in COVID-19 patients who did not need to be hospitalized, Toronto researchers have found in a report published on Friday in The Lancet Respiratory Medicine.

In a small trial, patients who received a single injection of peginterferon-lambda were more than four times as likely to test negative for the virus within seven days as patients who received a placebo.

Respiratory symptoms also appeared to resolve faster with peginterferon-lambda therapy, but the trial was too small to demonstrate a statistically significant difference. The team is planning a much larger trial, and studies are already underway testing the treatment in hospitalized patients.

SIA takes to the skies with fully vaccinated crew Singapore Airlines (SIA) began operating flights on Thursday with full sets of crew members vaccinated against COVID-19 as the city-state seeks to rejuvenate its status as an international travel hub.

The airline said pilots and cabin crew on three international flights from Singapore to Jakarta, Bangkok and Phnom Penh had received both of the required doses of the Pfizer-BioNTech vaccine.

The Singapore government has urged workers at the national airline to sign up for its inoculation programme in a bid to make SIA the world's first carrier with all staff vaccinated against COVID-19.