Related Content
UNLV immunologist Jeffrey Ebersole and other experts agree: The COVID-19 vaccines being rolled out across Nevada and the country this month have gone through rigorous testing for safety and effectiveness.
The challenge now is social acceptance, Ebersole said. The only way to change the trajectory of the pandemic is getting people vaccinated, meaning getting accurate information to the community about the vaccine is paramount, Ebersole said.
“There’s so much opportunity for misinformation to be out there that the scientists and the public health officials and the media really need to make sure that we’re getting accurate information out there, and hopefully helping to convince the population out there that this is a safe and effective vaccine — and they’re not just doing it for themselves, but they’re doing it for their families and communities, because we’re all protecting each other through this process,” Ebersole said.
Nevada will receive more than 164,000 doses of vaccines developed by Pfizer and Moderna this month. The initial allotment will go to hospital staff, skilled nursing facility staff and residents and frontline individuals.
Another round of doses is expected about three to four weeks after the initial batch; both the Pfizer and Moderna COVID-19 vaccines require two doses to be fully effective.
Federal officials have reported that widespread vaccinations won’t be rolled out until the spring.
Ebersole, a biomedical sciences professor and immunologist with UNLV’s dental school, sat down with the Sun to answer some questions about the vaccines. Answers have been edited for clarity.
How do the Pfizer and Moderna vaccines work?
Pfizer and Moderna, and others, I’m sure, have been working with what’s called nucleic acid vaccines for probably at least the last decade. They were just working on it targeting other types of viruses. So they were very well-positioned when COVID came along to say, "We’re just going to switch our direction a little bit and see if this same technology would work with COVID."
The other thing that allowed it to sort of fast track is that this coronavirus is very closely related to the virus about a decade ago that caused SARS and the one that caused MERS. Both of those were respiratory infections. They were caused by coronaviruses, and COVID is related to them, so we learned even a decade ago how those viruses cause the infection — and the way they do it is they have this spike protein that allows them to bind to lots of our cells and allows them to very rapidly infect and replicate in those cells.
This coronavirus uses the same type of a spike protein, so these vaccine companies not only had a technology that was sort of waiting to be used, but they had a good feeling of what the best target would be.
In most vaccines, you have to give enough of what’s called the antigen. That’s what induces the immunity. You have to give enough of it to trigger your immune response sufficiently strongly. With the nucleic acid vaccine, what they’re doing is they’re injecting the nucleic acid in liposomes, these lipid molecules, as the vaccine itself. Your cells pick up these pieces of nucleic acid and then your cells start making this spike protein, so they really amplify the availability of the antigen and your body can make a very strong immune response to the antigen.
What is the importance of following through with the booster shot?
You can get the single dosage, but the data from Pfizer or Moderna would say that you’re not sufficiently immune protected at that point in time.
How are the Moderna and Pfizer vaccines similar and how are they different?
They’re similar in that they’re both nucleic acid vaccines. As far as I’m aware, they both use liposomes to help deliver the nucleic acid to the host cells, so they are more similar than they are different. They both approach using the virus’ genetic material to produce the protein that our immune system responds to.
How can people decide which vaccine is better for them?
Relative to the technology, relative to the safety and efficacy of it, there’s no available information to say that one should choose the Pfizer versus the Moderna. There’s just no data to say that they would not both work very well.
Are there other vaccines in development and close to distribution?
There are a lot in development. The one that’s closest is the one from Oxford University and AstraZeneca. They’ve taken a different approach: They take the coronavirus nucleic acid for the spike protein and they put it into another, like a cold virus. That cold virus that they use won’t cause symptoms in humans, but it can infect and it can reproduce, and it produces this spike protein, so now your body reacts to that spike protein. With the Moderna and Pfizer one, we are asking our own cells to produce it.
Is there a nasal mist in development?
I have not seen that. The benefit of the nasal vaccine is that it induces what we would call mucosal immunity. When you get injected, your immunity is circulating in your blood. With the mucosal vaccine, the whole basis of that is stopping the infection from occurring because you’re stopping it right at the nasal surfaces, the lung surfaces and oral surfaces. I would not be surprised if they gradually move in that direction, but that type of vaccine technology is much less proven than the one where they inject it and cause what we call systemic immunity in your blood. This is such a global massive issue that they wanted to go with something that had a little bit more track record.
Compare the COVID-19 vaccine to the flu and other familiar vaccines.
The flu vaccine that everybody’s familiar with, we get that on a yearly basis. We get that on a yearly basis because the flu is a bit of a unique virus in that it actually can take its DNA, its genome, and it can scramble it, and it scrambles it each year. Usually that occurs as it transfers through various animal species. Usually this happens in Southeast Asia. Each year the public health officials, epidemiologists, infectious disease folks are sort of guessing at what the likely flu will look like for that season, and it’s based upon some of that early information coming out of Southeast Asia, so they prepare vaccine specifically to deal with the flu that year. It uses the whole flu virus and they kill it so that you can’t get a flu infection from that vaccine.
The other vaccine that people are very familiar with, the diphtheria-pertussis-and-tetanus vaccine, they actually use pieces of the proteins derived from the bacteria, and you get immunized with those and your body responds and protects you.
The mumps measles and rubella one is a vaccine that actually uses the mumps and the measles and the rubella virus, but they’ve been what’s called attenuated. In other words, once they’re injected, they will replicate but they can’t cause disease, so your body responds to the virus, but you can’t get the disease from these as well.
If someone has recovered from COVID-19, should they still get the vaccine?
There’s not a clear answer for that yet. I think the information that is out there would submit that if you’re already infected and recovered, getting the vaccine won’t hurt and in fact it may enhance a longer-term availability of protection for those individuals. But we just don’t have that data yet.
How much of Las Vegas would need to be vaccinated to get herd immunity and return to normal?
I’m not a public health doc, but in my reading of the science and in listening to those, I was actually in more of the area of 70 to 75% of the population needs to have immunity. That immunity can come with infection and recovery or it can come with vaccination.
This is a vicious virus. It is much more problematic than the annual flu in its morbidity and mortality and lack of understanding of who are the individuals in our population that would have this really bad outcome. That’s a difference that I think we really have to emphasize to the population. We need a large portion of the population who is immune. The best way to get that is through a vaccine.
The COVID vaccine is not only to protect us, but it’s to protect our community. It protects your family and your parents and your kids. If we want to get back to some level of normalcy, it’s going to take time to get up to that percentage of immunity. During that time, we’re going to have to continue to use the public health measures — the masking, the social distancing — and not let down our guard. The vaccine will more rapidly affect the trajectory of infections and hospitalizations and deaths and that’s a great thing, but it’s not going to make it go away.