CHICAGO (WLS) -- With many states reporting more cases, there has been a lot of talk about "herd immunity."
On Thursday, Dr. Anthony Fauci weighted in on the concept of "herd immunity."
President Trump returned to the campaign trail this week with a vengeance and held packed rallies while talking about herd immunity to beat the virus.
"'Heard immunity' is what we use for a lot of infectious diseases, whereby a large proportion of the population has immunity to the infectious condition, thereby preventing the spread," said Dr. Sadiya Kahn from Northwestern University Feinberg School of Medicine.
Kahn, an epidemiologist, said herd immunity should be achieved through a vaccine, not what the White House has suggested which is allow people who are at minimal risk to live their lives normally now in order to build up an immunity.
Kahn said the risk is huge if protocols are abandoned and life returns to normal.
"The numbers of cases will skyrocket, the hospitals would be overflowing and more and more people would be dying," Kahn said.
Kahn said her biggest concerns are the long term health effects on COVID-19 patients like Sotiria Tejeda.
Tejeda, 22, was perfectly healthy and athletic before she got sick in March.
Several months later, Tejeda's symptoms remain.
"I'm still short of breath, I sometimes have a cough that comes back, the fevers come at night all the time. My oxygen levels are low," Tejeda said.
Tejeda and doctors warned that COVID-19 is far from the common cold or the flu.
"We need to be making thoughtful choices, herd immunity is not one of those," Tejeda said.
Infectious disease experts said what they have learned is that COVID-19 is a dangerous disease that affects a broad spectrum of people of all ages.
Doctors said that waiting for a safe and reliable vaccine is the appropriate strategy.