Scientists hunt pandemic hotspots in race to test vaccines

Professor Adrian Hill, Director of the Jenner Institute, and Chief Investigator of the trials, holds a phial containing the Ebola vaccine at the Oxford Vaccine Group Centre for Clinical Vaccinology and Tropical Medicine (CCVTM) in Oxford, southern England September 17, 2014 [Photo:Reuters]

The first wave of the Covid-19 pandemic may be waning. For vaccine developers, that could be a problem.

Scientists in Europe and the United States say the relative success of draconian lockdown and social distancing policies in some areas and countries means virus transmission rates may be at such low levels that there is not enough disease circulating to truly test potential vaccines.