The Brazilian city of Manaus remains in a state of crisis as its second surge of Covid-19 cases continues to overwhelm its hospitals and kill hundreds of people every day. Dr Marcus Lacerda, a clinical researcher at the FioCruz Institute talks to Claudia about the city’s medical oxygen supply shortage and why the coronavirus has caused even more suffering during this second surge of cases. One of the commonest symptoms of Covid-19 illness is the loss of the sense of smell. It returns after a few weeks in most people but a significant minority still can’t smell anything many months later. We talk to Professor Carl Philpott of Norwich Medical School who’s led an international panel of nose doctors, assessing the evidence for the best therapies to restore the olfactory sense to people who’ve lost it following respiratory infections. So-called smell training comes out top as the most evidence-based approach. Carl explains how it works and we hear from two people who are trying to regain their sense of smell. Can some people suffer from the side effects of some drugs because they are expecting to experience them, and not because the drugs are actually causing them? That does seem to the case with statins, the cholesterol-lowering drugs prescribed to many millions of people around the world. Many people stop taking them because of side effects such as joint pain and muscle aches. But a fascinating study suggests that in many patients, it’s not the drugs that are the problem but something known as the nocebo effect - the evil twin of the placebo effect. We hear from Imperial College London cardiologist James Howard and one of the study’s participants. Doctor Graham Easton is Claudia’s guest of the week, talking about whether Covid vaccines will be effective against the new, more infectious variants of the coronavirus; a link between afternoon naps and sharper mental agility; and he comments on the nocebo effect in medicine. Presenter: Claudia Hammond Producer: Andrew Luck-Baker (Picture: A man holds an oxygen tank in Manaus, Amazonas State, Brazil in January 2021 amid the Covid-19 pandemic. Photo credit: Michael Dantas/AFP/Getty Images.)