By Chris Tye

CHICAGO (CBS) — Public health officials announced more than 10,000 new COVID-19 cases in Illinois Monday, but experts say there may be a light at the end of the coronavirus tunnel. Pfizer announced its COVID-19 vaccine is 90% effective.

The puts it on par with the effectiveness of the childhood measles vaccine. Pfizer bosses call it a historic moment.

The drug maker is asking for emergency authorization. They say by the end of the year they will have 50 million doses available.

If approved this vaccine has the upside of being mass produced easily, but the downside is the requirement it be kept extremely cold in transit.

“It’s the challenge to maintain that temperature from the manufacturer all the way to an individualizing arm. That would be the challenge,” said Dr. Habib Ahsan with the University of Chicago.

It needs to be refrigerated at a constant 35 degrees or frozen to -112 degrees.

“This level of temperature is not easy to say the least,” Ahsan said.

It is even trickier to try to get it to every corner of rural America.

We don’t know how many doses will be available when a vaccine rollout begins, but the Illinois Department of Public Health lays out this scenario in their plans filed with the Centers for Disease Control and Prevention: If there are 200,000 doses available statewide, suburban Cook County, which has 28% of the state population excluding Chicago, would get 28% of the vaccine — or 56,000 doses.

A CDC report outlines who within these groups gets priority access. Those include critical workers and first responders; those with an increased risk for severe COVID-19 illness; those in nursing homes and with underlying medical conditions; those with an increased risk of acquiring or transmitting COVID-19, such as racial groups with heightened numbers, tribal communities and those in college; and those with limited access to routine vaccinations, like those in rural areas, the disabled and the underinsured.

“Ninety percent effectiveness for a vaccine is quite promising,” said Ahsan.

Pfizer still needs to clear more testing to secure FDA approval.

Two non-Prizer trials are underway at the University of Chicago. One has finished patient enrollment, and enrollment is still underway for the other.

“How historic, it remains to be seen, based on the ultimate result when the full trial is completed,” Ahsan said.