What you need to know about the coronavirus right now

Vaccine hopes

Results from an early safety study of Moderna's coronavirus vaccine candidate in older adults showed that it produced virus-neutralizing antibodies at levels similar to those seen in younger adults, with side effects roughly on par with high-dose flu shots.

The findings are reassuring because immunity tends to weaken with age, Dr. Evan Anderson, one of the study's lead researchers, said in a phone interview.

Meanwhile, the chief executive of GlaxoSmithKline, the world's largest maker of vaccines, said she was optimistic the industry will be able to make an immunisation widely available next year.

Germany's CureVac said it has started a mid-stage study testing its experimental vaccine and plans to begin a decisive global trial with about 30,000 volunteers in the fourth quarter.

Treatment hopes

Oxford University said it would study whether the world's best-selling prescription medicine, adalimumab, was an effective treatment for COVID-19 patients, the latest effort to repurpose existing drugs as potential coronavirus therapies.

Adalimumab, sold by AbbVie under the brand name Humira, is a type of anti-inflammatory known as an anti-tumour necrosis factor (anti-TNF) drug. Recent studies have shown that COVID-19 patients already taking anti-TNF drugs for inflammatory bowel disease and inflammatory arthritis are less likely to be admitted to hospital.

Regeneron Pharmaceuticals said its experimental two-antibody cocktail reduced viral levels and improved symptoms in non-hospitalized COVID-19 patients, enhancing its chances of becoming a treatment for the disease.

Cases up among young U.S. adults

Coronavirus cases among young adults rose steadily across the United States in recent weeks as universities reopened, suggesting the need for this group to take more measures to prevent the spread of COVID-19, a U.S. health agency said.

Universities that want to reopen for in-person learning need to implement mitigation steps such as mask wearing and social distancing to curb the spread of the virus among young adults, researchers from the Centers for Disease Control and Prevention said in the report.

Between Aug. 2 and Sept. 5, weekly cases of COVID-19 among people aged 18 to 22 rose 55.1%. The Northeast region recorded a 144% increase while Midwest cases rose 123.4%, the report said.

Return to normal in Australia?

Australia's coronavirus hotspot of Victoria state maintained its steady downward trend in new infections on Wednesday as states began easing internal border closures, fuelling optimism about a return to normal.

Victoria's quick containment of a second wave of the outbreak prompted Western Australia state to relax its travel restrictions, allowing travelers from the southeastern state to quarantine at home rather than in a hotel from Monday.

Sydney Opera House, a national symbol, said it would work to reopen its venues from November after the New South Wales state government raised the seating capacity in theatres to 50% from Thursday.

Merkel says Germany can avoid second lockdown

German Chancellor Angela Merkel said on Wednesday that she wanted to do everything in her power to avoid another national lockdown as coronavirus infection numbers rise again in Europe's largest economy, expressing confidence the goal was achievable.

"We all want to avoid a second national shutdown and we can do that," Merkel said, adding that people knew much more about how to protect themselves and the health system than they did back in March, when a national lockdown was implemented.

Merkel and the leaders of Germany's 16 states have agreed to restrict the size of gatherings and to fine anyone who flouts tracking rules.