COVID-19, such as Rwanda and New Zealand, which said Monday it plans to open a virus-free "travel bubble" with the Cook Islands.With much of the world caught in a cycle of dispiriting outbreaks and economically crushing lockdowns, all eyes are on the race for a vaccine.A WHO overview said 165 candidate vaccines are being worked on around the world, with six reaching Phase 3 of clinical evaluation.But the WHO's emergencies director Michael Ryan warned that a vaccine was "only part of the answer," pointing to polio and measles as diseases with vaccines that have not been fully eradicated."You've got to be able to deliver that vaccine to a population that want and demand to have that vaccine," he said.- Europe feels the heat -Infections have.