A team of scientists from the University of Arkansas for Medical Sciences (UAMS) conducted an eight-month seroprevalence survey that found that at the end of 2020, 85% of the state’s population was still susceptible to the virus.

This project — recently published by the Public Library of Science ONE — focused on the number of Arkansans infected with the virus that causes COVID-19 between May and December 2020 and the primary similarities between the infections.

Victor Cardenas, a now-retired epidemiologist from the UAMS Fay W. Boozman College of Public Health and lead author of the report, said: “We used a random sample of adults to find out where the positive cases were, their demographics, occupation and lifestyle in the state, and to find out if they recall being around a COVID-19 patient inside or outside their household.

“Recent seroprevalence data from the Centers for Disease Control and Prevention indicates that 64% of Arkansas residents have been infected with the coronavirus. Our study ended in late 2020 and the level of infection has quadrupled since then.”

A seroprevalence survey uses antibody tests to estimate the percentage of people in a population who have antibodies to COVID-19. Antibodies are proteins that your immune system makes to fight infection. When a person gets a virus like the one that causes COVID-19, their immune system makes antibodies. An individual’s immune system can also produce antibodies from vaccination against a virus. Once a person has antibodies to a specific disease, they gain some protection against that disease or virus.

1,500 subjects were examined for the survey. Based on the data and estimates, there was a prevalence of just over 15% of the Arkansas population presenting COVID-19 antibodies as of December 2020 – or one in six people in Arkansas had evidence of COVID-19 infection.

As a result, most of the state was still vulnerable to infection despite the availability of vaccines. As of the summer of 2021, only 46% of Arkansas adults were fully vaccinated.

Combine that with the arrival of the Delta and Omicron variants, both of which were extremely transferrable, and Arkansas had a situation conducive to massive surges.

“The state is lagging behind in the number of people who have received the vaccine,” Cardenas said. “It even affects what is going on today. It’s not too late to get vaccinated and get your loved ones vaccinated. The vaccines are working.”

“Our study emphasized the importance of residents of this state getting the vaccine,” he said. Currently, 56% of Arkansans ages 5 and older are fully immunized and 13.2% are partially immunized, according to the Arkansas Department of Health.

The survey also drew attention to the large number of people who had COVID-19 but did not know they were infected. This also fueled the spread of the virus.

Using information from a nationwide probability sample, the researchers learned that there were portions of the Arkansas population that had unusually high rates of infection.

People with a lower level of education or low income had high rates of infection. People with an infected person living in the same household had high rates of infection. Some of the largest infection numbers in the state have also been linked to minorities.

The study also found that people with an essential job or occupation that did not allow them to work from home or socially distance themselves from their colleagues had a higher prevalence of infection. The survey also reports that regardless of the other risk factors, a significant proportion of those infected appear to have contracted the virus while visiting a friend or family member.

Meanwhile, Arkansans who stayed home, worked from home, and limited their face-to-face interactions with others had a much lower rate of infection.

“At the beginning of the pandemic, the focus was on contact tracing,” Cardenas said. “From an early stage, great emphasis was also placed on social distancing and effectively limiting contact between people. The social distancing worked.”

While simple safeguards make a difference, Arkansans must be willing to apply them, he said.

“Portability hasn’t changed, but the contact rate has gone down due to the lockdown. Every time we relaxed it, the transmission would resume,” Cardenas said. “The restriction of movement, wearing the masks – those things work.”

Cardenas acknowledged that most of the poll’s results came as no surprise; However, the research has lent further validation to what is known about best practices to protect Arkansas residents from another COVID-19 surge.

“Every time we let go of our vigilance, the number of COVID-19 cases increases,” he said. “The reason for this is that many people in Arkansas are still susceptible to the virus.

“We have to pay attention to what’s going on and to the latest trends. We have to get vaccinated. This also includes being boosted. You need to make sure you are protected and so are your household members.”