Editor’s note: This is the third article in a three-part report on COVID-19, featuring local epidemiologist Dr. Bonny Specker.

BROOKINGS – Don’t be in a rush to get infected with COVID-19 because you think it will give you “herd immunity,” warns a local epidemiologist, Dr. Bonny Specker. An epidemiologist studies diseases and how they spread.

To reach herd immunity, many people would have to contract the virus and the death count would be “a very large number,” she said. “That is not a good idea.”

You don’t want to get this disease: COVID-19 is dangerous in and of itself, but the after-effects could reach far into the future, she said.

Finally, there is evidence the antibodies wear off and people might be able to get COVID more than once, so there would be no “herd immunity” anyway, she said.

The numbers don’t lie

Herd immunity isn’t a simple concept, Specker said.

“With herd immunity … you have to have a very large percent of the population that’s immune. In the case of COVID, people think that’s around 70%. So 70% of the population would either have to have had the disease or been vaccinated against it,” Specker said.

Since there is no vaccine, that means 70% of the population would have had to get COVID, which can be deadly.

“You’re talking about a very large number of deaths in order to get 70% immunity through having the disease,” Specker said.

She pointed to Sweden as an example. Sweden didn’t shut down the country when COVID hit. 

“They thought that it would be more important for the economics of the country to just keep it going,” Specker said. “They’ve had a huge number of deaths.”

In a country that has a population of a little more than 10 million, there have been nearly 80,000 COVID-19 cases and almost 5,700 deaths, according to Johns Hopkins University & Medicine (coronavirus.jhu.edu).

Specker said it was important to look at the mortality rate, which is the number of deaths per million people and she compared Sweden’s results with their neighbor, Norway.

Norway did shut down the country. Norway has a population of almost 5.5 million people, but has had only 255 deaths from COVID, according to coronavirus.jhu.edu.

“Big difference,” Specker said.

Sweden has had approximately 545 deaths per million people; Norway has had approximately 46 deaths per million people, “so a 10th of the death rate that Sweden has,” Specker said.

“Now (Sweden’s) economy has really tanked out compared to their neighbors that shut down,” Specker said.

To compare it to South Dakota, she said about 2% of South Dakota’s population has been exposed to COVID-19. As of Aug. 3, South Dakota has had 9,020 positive cases and 135 deaths from COVID. Brookings County has had 120 cases and one death.

Herd immunity isn’t magic, Specker said.

“Try to have patience with the social distancing and the mask-wearing until there’s a vaccine and get the ‘herd immunity’ through the vaccine. Then you don’t have the deaths,” Specker said.

Antibodies may not protect

Getting COVID-19 may not give you long-term immunity, anyway.

Scientists have been closely monitoring the blood of people who have had COVID-19, looking for antibodies. They’re finding them, but don’t bank on those antibodies to save you in the future, Specker said.

“There are quite a few studies that have looked at the amount of antibodies. Antibodies are what’s in your body that are gonna fight the virus … so the idea is next time you’re exposed to it, the antibodies will kill the virus,” she said.

“But what they find is the level of those antibodies decrease over time, so you’ll be immune for a while, but it’s not clear how long,” Specker said.

That’s why the race to find a vaccine is so important.

COVID not going away

The COVID-19 pandemic is not going away, and science is racing to find a vaccine to combat it. Vaccines help prevent many different diseases: polio and measles among them, and Specker thinks COVID will be added to the list.

“COVID is probably gonna end up like flu vaccine, where (you get the vaccine) every year,” she said.

She also speculated any future COVID vaccine will have to be tweaked every year, just like the flu vaccine is. 

“No one knows that yet,” Specker said, but “viruses change. They mutate.”

If a vaccine targets a certain aspect of the virus, then that part of the virus changes, the vaccine won’t be as effective and a new vaccine will be needed, she said.

“That’s what happens with flu. You have the different strains of flu,” Specker said. 

Because the virus that causes COVID is in the same family as the one that causes the common cold, they suspect people will be able to get COVID more than once, just like you get the cold repeatedly, she said.

“We can’t assume that this (COVID) virus, if you get sick, that you’re gonna be immune to it,” Specker said.

Long-term brain problems

There could be long-term health problems for people who have contracted COVID, which researchers are just beginning to study.

There were two studies, one done in Iceland and the other in Italy, where researchers took random samples from the population and tested them for COVID-19. Half the people showed no signs of the disease.

“Of the remaining 50%, 40% of those are probably gonna have fairly moderate type illness … 10% are gonna have really bad outcome. Well, that’s just at that time,” Specker said.

Of the 40% who get sick from COVID-19, they “could end up having these long-term sequellae (residual effects) that we know nothing about,” Specker said. 

She cited an article in The Guardian on what British neurologists have learned from more than 40 mildly affected or recovering COVID-19 patients who were experiencing serious or potentially fatal brain conditions.

“The cases, published in the journal Brain, revealed a rise in a life-threatening condition called acute disseminated encephalomyelitis (Adem), as the first wave of infections swept through Britain,” according to The Guardian. One woman, 59, died of the complication. Survivors have breathlessness and fatigue, others have numbness, weakness and memory problems.

“Some patients are left with long-term disability, others can make a good recovery,” The Guardian quoted Michael Zandi, a senior author on the study and a consultant at the institute and University College London Hospitals NHS foundation trust.

Because COVID is so new, no one can say for sure what the long-term effects for anyone are, Specker said.

“That is one of the scariest things,” she added.

Contact Jodelle Greiner at jgreiner@brookingsregister.com.