In an incredible scientific feat, COVID-19 vaccines have been developed within less than a year after the virus was first detected. Several vaccines that have become available have shown different levels of efficacy. So what is vaccine efficacy? Dr Lee Hampton, a paediatrician and medical epidemiologist with GAVI, the Vaccine Alliance, explains.
As Ebola immunization scales up in Guinea, the country’s neighbouring nations are on high alert, urgently preparing to detect, isolate and manage any cases and quickly stamp out potential cross-border outbreaks.