COVID-19 Study

Dear resident of Raatuse 22 dormitory

We invite you to participate in the study

„SARS-CoV-2 outbreak in Tartu Raatuse 22 student dormitory in April 2020: an outbreak investigation to assess the incubation period and serial interval“.

Participation in the study is voluntary. You can decide to participate and can decide not to participate. You can also start to fill in the questionnaire and then abort it at any time without any consequences. Please read the following information before deciding to participate.

  • The COVID-19 is caused by SARS-CoV-2, a virus discovered in China in December 2019 that can cause serious illness in humans. COVID-19 has been declared a pandemic by the World Health Organization.
  • Mathematical models are used to describe the spread of communicable diseases in order to predict the number of cases and the impact of control measures. The models are based on data collected from outbreak studies. Important characteristics of an outbreak are the incubation period (time from infection to onset of the disease) and the serial interval (time from onset of the disease in infector person to the onset of the disease in the infected person).
  • In April 2020, a COVID-19 outbreak occurred in the Raatuse 22 student dormitory in Tartu. The aim of the present study is to evaluate the incubation period and serial interval on the basis of the data of the Raatuse 22 outbreak and to use the obtained results to specify the models describing the spread of COVID-19 in Estonia.
  • In order to participate in the survey, we ask you to answer questions about the results of the virus test performed on you, the symptoms of your illness and the meetings of the residents in the student dormitory during April. Based on your answers, we can find the probable dates of infection and the dates when the symptoms in the patients started, which is the basis for estimating the incubation period and serial interval.
  • It does not take more than 5-10 minutes to complete the questionnaire; depending on their test results and the signs of the disease, the residents are asked different numbers of questions.

For the study to be successful, it is important that as many residents as possible of the Raatuse 22 dormitory answer the questions, regardless of the result of their virus test and the presence of signs of the disease.

This is an anonymous survey: you will not be asked for information that would allow to relate your answers to your identity.

We will be grateful if you decide to participate in the survey. By doing this you will help us to better model the impact of COVID-19 in Estonia.

The study is conducted by:

Marika Tammaru (Research Department of the East Tallinn Central Hospital)

Krista Fischer (Institute of Mathematics and Statistics, University of Tartu)

You can contact the researchers by e-mail

The collected data will be destroyed after their analysis; they will not be stored or shared.

The study is approved by Research Ethics Committee of the University of Tartu.

By completing the questionnaire, you give your consent to participate in the study


The questionnaire is open until May 26th.