COVID-19: What you need to know about the coronavirus pandemic on 4 August

Confirmed cases of COVID-19 have passed 199.5 million globally, according to Johns Hopkins University. The number of confirmed deaths stands at more than 4.24 million. More than 4.21 billion vaccination doses have been administered globally, according to Our World in Data.

Australia has reported one of its youngest COVID-19-related deaths, a man in his 20s, who had no underlying health issues and was unvaccinated.

Authorities in the state of Queensland have warned separately that a lockdown in capital Brisbane could be extended beyond Sunday.

New York has become the first major US city to require proof of COVID-19 vaccination at restaurants, gyms and other businesses.

Dubai's state airport operator expects to see a surge in passenger traffic over the coming weeks and months after the UAE announced an easing of travel restrictions from African and Asian countries.

New COVID-19 cases in Turkey jumped to nearly 25,000 yesterday, the highest level in almost three months.

Macau, China, will test its 600,000 people and close some entertainment venues after confirming four new COVID-19 cases.

Thailand has reported 20,200 new COVID-19 cases and 188 deaths, both the highest daily increases of the pandemic so far.

Mexico has reported 18,911 new confirmed COVID-19 cases and 657 deaths. The government has said the real number of cases is likely much higher.

A large English prevalence study has found that fully-vaccinated people have around a 50-60% reduced risk of infection from COVID-19, including those who are asymptomatic.

The research, part of Imperial College London's REACT-1, was conducted at a time when the Delta variant had completely displaced the previously dominant Alpha variant.

The researchers said that overall, the prevalence in unvaccinated people was 1.21%, three times higher than the 0.40% prevalence in fully vaccinated people, and that the viral load among people with COVID was also lower in vaccinated people.

COVID-19 vaccination programmes in Latin America should focus on vulnerable groups, such as indigenous people and the homeless, Unesco said yesterday.

Health workers, educators, the elderly and people with pre-existing conditions have been prioritized, but the region's economic divisions should also be considered, an official told Reuters.

"This is the region hardest hit by COVID in the world. And it is a region with a lot of inequality," Guillermo Anllo, regional head for Latin America and the Caribbean of the agency's Scientific, Technological and Innovation Policy Program, said in a telephone interview from his office in Montevideo.

Unesco projects that just a third of the population of Latin America and the Caribbean will be vaccinated by the end of 2021.