AIIMS Director Dr Randeep Guleria says India needs to have an aggressive surveillance and containment strategy against UK's coronavirus strain. Identifying sudden clusters is key, he says. All those arriving from UK need to be quarantined. All passengers who test negative also need to be quarantined and then ideally re-tested after the end of the quarantine, Dr Guleria says. Even if you are negative on arrival, you could be in the incubation period, he adds.