Latest on the worldwide spread of the coronavirus

Pfizer Inc said on Wednesday a booster dose of its two-shot COVID-19 vaccine spurs a more than three-fold increase in antibodies against the coronavirus, as the company seeks U.S. regulatory approval for a third injection.

DEATHS AND INFECTIONS EUROPE * Europe's medicines regulator has approved additional manufacturing sites for mRNA-based coronavirus vaccines developed by Pfizer-BioNTech and Moderna. * Switzerland ordered millions more doses of COVID-19 vaccine as it braced for a resurgent wave of coronavirus that could require more restrictions on public life. ASIA-PACIFIC * Sydney's COVID-19 infections hit a daily record, putting parts of the health system under pressure, officials said, calling for vaccinations to be stepped up to stem the tide of hospital admissions. * India will supply millions of additional vaccine doses to its states to try to inoculate all schoolteachers by early next month, as the country gradually resumes physical classes. * Thailand's coronavirus task force called on pregnant women in the country to get vaccinated, citing a higher risk of deaths among those who become infected with the coronavirus.