Don’t rely on contact-tracing apps

EVERYTHING HAPPENSThe EconomistThe Economist Today faster in a crisis. Faced with covid-19, vaccine-makers are cutting as many corners as they safely can. Anti-viral drugs are being rushed into clinical trials. Even so, it will be months until anything is available. With 297,000 people recorded dead, the wait is agonising. But caution is crucial. Medicine’s history is full of promising treatments that, when tested, turned out not to work or even to cause harm.