The Moderna COVID-19 vaccine was one of the first to begin human trials. Yet, Dr. Richard Novak, who is overseeing the study at University of Illinois at Chicago, said a vaccine in October is not realistic.
"As far as we are going to have an answer from that study, it's still going to be months from now and possibly longer," Novak said.
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Dr. Robert Redfield, director of the Centers for Disease Control and Prevention, told lawmakers the same thing Wednesday, only to be scorned a few hours later by President Donald Trump, rejecting his own scientists.
The president said a vaccine will be available by October, before the Nov. 3 election. The medical community said the mixed messaging and misinformation is damaging.
"I think, when the public hears there is going to be a vaccine even before it's ready, there is going to be a great deal of reluctance to take the vaccine," Novak said. "And that is nine tenths of the battle."
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Novak is also concerned the mixed messaging from the federal government will deter people from volunteering for vaccine trials. At UIC, some participants have already dropped out, but the University of Chicago is in the process of recruiting people for future COVID-19 trials.
Doctors said it's important to trust the scientists, who have a stake and expertise in infectious diseases
"Those of us who have training in epidemiology such as myself, we really want to protect people from the virus because we know how incredibly dangerous and lethal it is," said Dr. Jade Pagkas-Bather, an infectious disease specialist with University of Chicago Medicine.
There has also been mixed messaging over masks. The CDC and infectious disease experts said even when there is a safe vaccine for everyone, a mask remains an effective way to prevent the virus from spreading.