Pfizer CEO Albert Bourla has said that those who refuse to take a coronavirus vaccine will be the weak link which will allow the virus to spread again, CNBC reported on Tuesday. In his statement, Bourla said that those who choose not to get vaccinated will not only affect their own lives, but the lives of others as well. Pfizer is one of the companies developing a vaccine for COVID-19, and is in late-stage testing for inoculation and potential side effects which may be caused by the vaccine. To that end, in order to make sure the vaccine is safe to use, several medical companies have signed a pledge to uphold scientific standards even during the race to develop the coronavirus vaccine. The companies, including Pfizer, GlaxoSmithKline and AstraZeneca, issued what they called a "historic pledge" after a rise in concern that safety and efficacy standards might slip in the rush to find a vaccine. Pfizer has gone further, saying the company will only request authorization from the Food and Drug Administration after data shows that its vaccine is safe and effective.On Sunday, it was reported that nearly a quarter of Israelis would not take a coronavirus vaccine if it was approved for use, according to a recent survey.The survey, conducted by Assuta Medical Center in conjunction with Midgam, found that while about three-fourths of Israelis said they “think” or are “sure” they would take such a vaccine, 20% said they don’t think so or are sure they would not. Another 6% said they do not know.Reuters contributed to this report.