A new trial is about to start in the UK, seeing if different vaccines can be mixed and matched in a two-dose schedule, and whether the timing matters. Governments want to know the answer as vaccines are in short supply. Oxford University’s Matthew Snape takes Roland Pease through the thinking.

Despite the numbers of vaccines being approved for use we still need treatments for Covid-19. A team at the University of North Carolina is upgrading the kind of manufactured antibodies that have been used to treat patients during the pandemic, monoclonal antibodies. Lisa Gralinski explains how they are designing souped-up antibodies that’ll neutralise not just SARS-CoV-2, but a whole range of coronaviruses.

Before global warming, the big ecological worry that exercised environmentalists was acid rain. We’d routinely see pictures of forests across the world dying because of the acid soaking they’d had poisoning the soil. In a way, this has been one of environmental activism’s success stories. The culprit was sulphur in coal and in forecourt fuels – which could be removed, with immediate effect on air quality. But biogeochemist Tobias Goldhammer of the Leibniz Institute in Berlin and colleagues have found that sulphur, from other sources, is still polluting water courses.

There’s been debate over when and where dogs became man’s best friend. Geoff Marsh reports on new research from archaeology and genetics that puts the time at around 20,000 years ago and the place as Siberia.

Could being happier help us fight infectious disease?

As the world embarks on a mass vaccination programme to protect populations from Covid-19, Crowdscience asks whether our mood has any impact on our immune systems. In other words, could being happier help us fight infectious diseases? Marnie Chesterton explores how our mental wellbeing can impact our physical health and hears that stress and anxiety make it harder for our natural defence systems to kick in – a field known as psychoneuroimmunology. Professor Kavita Vedhara from the University of Nottingham explains flu jabs are less successful in patients with chronic stress.

So scientists are coming up with non-pharmacological ways to improve vaccine efficiency. We investigate the idea that watching a short feel-good video before receiving the inoculation could lead to increased production of antibodies to a virus. And talk to Professor Richard Davidson who says mindfulness reduces stress and makes vaccines more effective.

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