Scientists expect one or more coronavirus vaccines to emerge from the multiple research efforts underway, but caution that the overall impact depends on public acceptance. A vaccine could be only partially effective in protecting any one individual, as is the case with flu shots. Without "herd immunity" through mass vaccination, COVID-19 would continue to spread, although vaccinated individuals would be at least somewhat protected.
Dr. Anthony Fauci, the prominent government spokesman on the pandemic, cited "anti-science, anti-authority, anti-vaccine" views in the U.S. as an obstacle in a CNN interview. A May CNN poll found that a third of Americans would not try to get a vaccine. Fauci said a vaccine only 75% effective, taken by only 2/3 of the population, would be "unlikely" to stop the disease.