From Memorial Hermann Hospital - The Next Steps for COVID-19: Antibodies, Herd-Immunity and Vaccines
As time has progressed, we’ve learned more about COVID-19. And not all of the developments have been encouraging.
“But there’s hope, thanks to great work, hustle and collaboration of scientists on a global scale,” says Annamaria Macaluso Davidson, MD, MBA, CMQ, associate vice president of medical operations at Memorial Hermann Medical Group.
As time has progressed, we’ve learned more about COVID-19. Here's what you should know.
For those without a medical degree, Dr. Davidson explains terms and expectations for antibodies, vaccines and herd immunity—and how scientists are fighting COVID-19.
Q. What are antibodies?
Antibodies are proteins produced by our body to fight infection. These warriors surround and neutralize the coronavirus that threatens to infect our cells.
Should the virus slip through and you fall ill, some of these soldiers will guard you post-recovery. They can call in reinforcements, giving us immunity.
“For the most part, if you’ve had COVID-19, you have protection in the short term,” Dr. Davidson says.
According to Dr. Davidson, studies suggest immunity lingers at lease three months—but antibodies don’t serve as a get-out-of-jail-free card. “Researchers don’t know yet whether it will last months or years longer,” she says.
Q. How are vaccines made?
Many vaccines isolate and deactivate genetic pieces of the virus. Others deliver a low dose of a live virus. According to Dr. Davidson, either approach will awaken your body’s warriors, or immune response, to slay the assailing virus.
“There are more than 160 vaccines in development for the coronavirus” she says.
Q. What are the steps to make a vaccine?
Creating a safe, effective vaccine involves four stages.
Scientists start with preclinical testing, in which vaccines are tried on mice, rats or other animals.
Only then do scientists move to phase one, in which a small number of volunteers —as few as 30—receive the vaccine to determine safety and dosage levels.
Phase two expands that to hundreds of men, women, children and the elderly to reveal immune response and side effects in a broad population.
The final phase looks at efficacy in a large scale, double-blind, placebo-controlled study, in which some participants get the vaccine and others don’t. To avoid biases, neither participants nor researchers know who’s getting the vaccine and who isn’t—till afterward. “Researchers see whether the vaccine produces enough of an immune response to control the disease,” she says.
If a vaccine is found to be safe and effective in half of recipients, the U.S. Food and Drug Administration approves it, and then it goes to market—and to battle.
To speed the process, some studies are combining phases one and two, or phases two and three, Dr. Davidson explains. “The timeline is much faster than usual,” she says.
At least one entrant in the viral sweepstakes, Moderna, reached phase three in late July, with people across the nation, including Houston, participating. That vaccine is delivered in two doses, taken four weeks apart.
Q. What is a realistic timeline for having a vaccine?
Usually vaccines take at least a year and a half to reach the marketplace, but Dr. Davidson believes worldwide efforts will lead to approved vaccines by early 2021, and possibly as soon as this December.
Federal and private sectors already are exploring how to ramp up production and distribution so that Americans nationwide can be vaccinated as soon as possible, she says.
Q. What is herd immunity, and can it be achieved?
When enough people in a population are resistant to or have immunity to a virus, that’s called herd immunity.
At that threshold, even those without individual immunity have a level of protection because the virus can’t be spread as easily. That may be due to a vaccine.
COVID-19 is crafty. And to deliberately go to war with the disease without the backup of a vaccine could be costly. “We have to get there the right way,” Dr. Davidson says.
That way is not via COVID-19 parties, where guests deliberately gather to expose themselves to the coronavirus. “Do not get sick on purpose, because we don’t know what your response will be,” she says.
While some may have mild symptoms, others may have long-term health impacts. “We’re still learning about the disease’s consequences.”
Obesity, diabetes, lung disease and autoimmune disorders escalate your risks.
Q. What should people do while awaiting a vaccine?
“Stay as healthy as you can,” Dr. Davidson says. “Don’t stop addressing your healthcare needs for fear of catching COVID-19.”
Also stay up-to-date for flu, shingles, measles and other vaccines. “Vaccines are really important to keep you and your children well,” she says. “They help protect pediatric and vulnerable populations.”
Exercise, eat a healthy diet, sleep well, continue to practice social distancing and wear masks.
“Keep calm and carry on,” she says. “And wash your hands. It’s important.”
The information in this article was accurate as of August 25, 2020.