Study on coronavirus prevalence launched

Today, the University of Tartu researchers start a three-month study on the prevalence of coronavirus in Estonia among both symptomatic and asymptomatic people. For that, at least 16,000 residents of Estonia based on a random statistical sample will be interviewed and invited to be tested for coronavirus.

The study consists of eight waves of one week with 2000–4000 people interviewed and tested in each wave. Today, the social and market research company AS Emor sends the electronic invitation and questionnaire to the first 2,000 people who have been randomly selected to participate in the study based on data retrieved from the population register. Phone interviews will be done with elderly people who cannot fill in the electronic questionnaire. Participation in the survey is voluntary for all people who receive the invitation and people may withdraw from the survey any time.

The electronic questionnaire can be completed in Estonian or Russian within five days. After filling in the questionnaire, the person will receive a call from the joint testing call centre of SYNLAB and Medicum to agree on when the person can come to the public testing site by car. Testing by a nasopharyngeal swab through an open car window is done in Tallinn, Tartu, Narva, Pärnu, Viljandi, Rakvere, Kohtla-Järve, Haapsalu, Paide, Jõgeva, Kuressaare and Kärdla.

For people with special needs or for those who are unable to drive to the testing site by car, the private medical companies will organise testing for coronavirus at home. SYNLAB analyses the samples for coronavirus RNA, indicating an active infection.

“We have sufficient capacity for both the drive-through testing sites and testing at home to ensure high-quality and timely testing of people referred by family doctors, working on the frontline and involved in the study,” confirms the coordinator of public testing, CEO of Medicum Tõnis Allik. “By cooperating with the University of Tartu in this project, we are hoping to bring benefit both to the tested people and the country as a whole.”

CEO of SYNLAB Estonia Rainar Aamisepp added that an average of 1,000–1,500 coronavirus samples are analysed at their laboratories every day, while their maximum capacity is 3,000 samples. “Thanks to the sufficient reserve of capacity we can partner with the University of Tartu in the project we consider very important. It helps us to know more about the coronavirus and the spread of the disease it causes, to keep the spread under control and thus better plan our gradual return to normal life,” explained Aamisepp.

All infected persons identified during the study will be monitored and interviewed weekly until the disease subsides. If the infected person is asymptomatic, the person will be interviewed for two weeks.

The head of the study, Head of the Institute of Family Medicine and Public Health, Professor Ruth Kalda said that the study will involve a random selection of men and women from different age groups from different counties based on the distribution of Estonian population. “Thus, the respondents will form a small model of the Estonian society. Based on the results of the study, we can draw conclusions on the actual spread of coronavirus in different population groups and provide the government with weekly evidence-based information for modifying the measures of the emergency situation,” Kalda added.

In addition to data on the actual prevalence of the virus, the study will give insight into the changes in the number and percentage of the infected and the factors these numbers are connected to. Also, by comparing the results of the interviews and testing, the study will reveal the main background characteristics and risk factors of infection (e.g. concomitant diseases, size of household, socioeconomic status, types of contact, etc.) and how they relate to prevalence. By monitoring both symptomatic and asymptomatic infected persons, we can get information on the course of the infection and the disease and how this relates to the background characteristics and risk factors of the person.

Further information: Ruth Kalda, University of Tartu, Head of the Institute of Family Medicine and Public Health, Professor of Family Medicine, +372 5698 5599, ruth.kalda@ut.ee