Results of the most recent wave of the COVID-19 prevalence study led by the University of Tartu (TÜ) indicate that nearly one in 30 adults in Estonia is currently infected with the COVID virus and is still contagious, comparable to late March figures. According to researchers, however, there is no cause for alarm as the course of the disease is now mostly mild.
During the study wave from August 17-29, a total of 2,570 adults across Estonia were tested for COVID. Of these, 5.5 percent were infected with the COVID virus, but 3.3 percent, or one in 31 adults, were contagious, according to a TÜ press release.
As found in previous study waves as well, COVID prevalence was lowest among those who have recovered from the disease and have also been vaccinated against COVID.
Although current infection rates are comparable with the end of March, the burden on hospitals is nonetheless three times lower, said study lead Ruth Kalda, professor of family medicine and director of TÜ's Institute of Family Medicine and Public Health.
"The predominant COVID strain is omicron BA.5, which causes relatively mild symptoms," Kalda explained. "Therefore, despite the current rather wide spread of the virus, there is probably no need for serious special measures, and we can head into the new school year quite calmly."
This wave of the COVID antibody prevalence study included 2,431 adults. Of these, the presence of antibodies was confirmed in 88 percent.
Antibodies were found in almost all vaccinated people, 70 percent of those who have not been vaccinated but have recovered from the disease as well as 37 percent of those who have not been vaccinated nor are aware of having had the disease.
"Antibody prevalence has remained almost unchanged since March," Kalda said. "I assume we've reached a certain level that will persist: just as quickly as antibodies disappear from some people's blood over time because it's been a long time since they were infected or had their last dose of vaccine, others will develop antibodies either in recovering from the disease or via vaccination."
The prevalence of antibodies in people over 65, however, is close to 95 percent.
Results of a behavioral survey conducted during the study indicate that less and less attention is being paid to precautions aimed at preventing the spread of infection. Although recent data indicates that nearly one in 10 adults has been in contact with an infected person, most do not take any action to prevent the further spread of the infection.
Kalda noted that although the currently prevalent COVID strain tends to cause milder symptoms, it would still be wise for at-risk groups to protect themselves against possible severe disease by getting a booster dose of the vaccine.
"In that respect, the survey data is quite encouraging: nearly half of vaccinated seniors who have not yet received a booster dose plan to do so," she highlighted. "Older men are particularly willing to get a booster dose."
According to Mikk Jürisson, chief executive of the study and associate professor of public health at TÜ, monthly monitoring is currently the only way to gain a comprehensive picture of the prevalence of COVID in the adult population as well as to assess future trends.
"A big thank you to everyone who has agreed to participate in the survey thus far or will do so in the future," Jürisson said. "In such a rapidly changing environment, your willingness to cooperate has provided evidence-based support in tackling health issues important to society as a whole."
The COVID-19 prevalence study is being conducted by a broad-based research group at TÜ in cooperation with Synlab Eesti, Medicum and Kantar Emor.
Editor: Aili Vahtla