Antibodies against the novel coronavirus declined rapidly in the British population during the summer, a study found, suggesting protection after infection may not be long lasting and raising the prospect of waning immunity in the community.

The European Union agreed to pay more than 1 billion euros ($1.2 billion) to Gilead for a six-month supply of the company’s antiviral drug remdesivir, shortly before the publication of final results for the largest trial of the Covid-19 medication.

The widely used BCG tuberculosis vaccine will be tested on frontline care workers in Britain for its effectiveness against Covid-19, researchers running the UK arm of a global trial said.

The global coronavirus death toll surpassed 1 million according to a Reuters tally, a bleak statistic in a pandemic that has devastated the global economy, overloaded health systems and turned daily life upside down.

Researchers from Aarhus University in Denmark published research indicating that Parkinson’s disease is actually two types of the disease.

The adverse events that led to a pause in trials evaluating AstraZeneca Plc’s Covid-19 vaccine candidate may not have been associated with the vaccine itself, according to a document outlining participant information that was posted online by the Oxford University.

AstraZeneca resumed British clinical trials of the company’s Covid-19 vaccine, one of the most advanced in development, after getting the green light from safety watchdogs.

Political polarization and online misinformation are threatening vaccination programs worldwide, with public trust volatile and varying widely between countries, according to a global vaccine confidence study.

AstraZeneca should still know by year-end whether the company’s experimental vaccine protects people against coronavirus, as long as AZD1222 is cleared to resume trials soon, the drugmaker’s chief executive said amid doubts over the potential vaccine’s rollout.

The U.S. Centers for Disease Control and Prevention (CDC) asked state public health officials to prepare to distribute a potential coronavirus vaccine to high-risk groups as soon as late October, documents published by the agency showed.