Corona Research Limburg

In March 2020, the World Health Organization (WHO) declared Europe as the epi
centre of the new coronavirus (SARS-CoV-2) pandemic [1]. Within six weeks of
the first reported confirmed corona patient in Europe, all 27 countries were
affected. In the Netherlands, the first confirmed COVID-19 patient was reported
on 27 February 2020 [2]. Limburg is one of the most severely affected
provinces with 442 infections per 100,000 inhabitants on 5 Aug 2020 [3].
The spread of the virus slows down when (part of) the population develops
immunity in a natural way [4]. The minimum proportion of people who must have
developed immunity to SARS-CoV-2 to be able to speak of group immunity has been
estimated at 67%, assuming that one infected person can infect two to three
others on average [5]. Several studies are conducted to gain more insight into
the obtained immunity against SARS-CoV-2 in the Dutch population
(seroprevalence). The National Institute for Public Health and the Environment
(RIVM) is currently conducting several studies. The RIVM previously
investigated the presence of SARS-CoV-2 antibodies in fingerprint blood of
2,096 people [6]. Antibodies could be detected in 5.5%, with no difference
being found between men and women. Individuals with antibodies against
SARS-CoV-2 were more likely to have complaints such as reduced odour/taste,
fever, general malaise, muscle pain and joint pain, compared to individuals
without antibodies. RIVM is currently conducting a large-scale study into group
immunity in a population of 6,000 Dutch people who previously participated in
the Pienter Study [7]. In the Pienter study, SARS-CoV-2 antibodies will be
determined using fingerprint blood too.
Finally, the RIVM, in collaboration with Sanquin, is investigating the extent
to which the Dutch population has SARS-CoV-2 antibodies. However, this only
concerns blood sample analysis and no additional data are collected [7]. Until
now, further studies into the presence of SARS-CoV-2 antibodies in a blood
sample obtained via venepuncture (seroprevalence) are lacking.
It is highly important to generate knowledge about the nature and determinants
of the spread of SARS-CoV-2 in Limburg, a region severely affected by the
COVID-19 pandemic. By researching determinants, we aim to generate knowledge
about the occurrence per region, and in certain groups (e.g. old/young,
male/female, chronically ill/not ill). We hope to gain more insight into why
Limburg has been hardly affected by looking at possible risk exposure (e.g.
attending an event, visiting choirs), relationship with border countries (e.g.
possible exposure in Gangelt) etc. The results of the study will, in addition
to providing insight, contribute to the more targeted deployment of COVID-19
measures in 2020.
Therefore, the aim of the study is to provide information about the
determinants associated with the proportion of positive SARS-CoV-2 antibody
tests in the Limburg population.

Which determinants (risk exposure, symptoms, compliance with measures) are
associated with a positive SARS-CoV-2 antibody test in inhabitants of the
province of Limburg?

Cross-sectional
The study is a cross-sectional study with invasive measurements.

Duration
The study (the collection of materials and data) is expectedly conducted within
a time frame of approximately 10 weeks.
However, the exact study duration depends on the number of respondents. The
targeted number of respondents for this study is 10,000 people.

Recruitment
Recruitment takes place through open media channels, where we refer to the GGD
website that contains all the relevant information on the study.

Enrolment
People who are potentially interested in participating in the study, can visit
the GGD website where they find all the study information. The website also
contains a weblink to register for the study after someone has had enough time
to think about it. After registering, the person will receive an email with the
detailed study information (including the Patient Information Letter). Also the
person will be contacted by phone by our call-center (*mondeling*). At that
moment, the study will be explained and the person can ask questions. Also at
that moment, the enrolment visit is scheduled. Enrolment entails registration,
information (written and by phone) and the informed consent procedure. The
enrolment visit takes place at least two days after the study information had
been send to the person (by email).
A total of 10,000 people can be included in the research. After the first
10,000 persons have registered, i.e. they have registered for the study via the
website, the registration will be closed. Other persons (up to 3,000) can then
still apply for the reserve list. If a person (out of the original 10,000)
does not wish to participate, the person who first registered for the reserve
list will be contacted for enrolment.


Participation
Participants have registered to be potentially interested in participating in
the study, they have been called (by the call-center) to schedule the enrolment
visit (to provide informed consent and have their blood drawn for testing on
SARS-Cov-2-antibodies. Participation starts with the blood drawing AFTER the
participants provided written informed consent. When the participants provide
consent, again they are given the opportunity to ask questions and
participation eligibility will be checked. After the blood test, participants
receive the online questionnaire (instructions are provided). A helpdesk is
available to help fill in the questionnaire.

Blood test
Minimally two days after (usually this will be a few days later, depending on
the logistics of the blood-sampling and staffing), blood is taken by
venipuncture (10ml EDTA 1 tube) by trained and qualified staff, under the
responsibility of the GGD.

Result
The blood-samples are tested batchwise in the laboratory of the MUMC+. The GGD
will inform the participants of the results (positive or negative) via email.
This means of communication allows for providing additional information and
explanation on the interpretation of the blood-test, information about corona
and other issues relevant for infection-prevention and public health.

This study is low risk.
The questionnaire is non-invasive, it costs some time to fill in (about 35-40
minutes).
The venipuncture is a minuma burden. It is being conducted by well-trained and
qualified staff, under the responsibility of the GGD. The risk therefore is
very small.
The participants receive the result of the corona-antibody test. Thet will be
extensively informed about the interpretation of the test results.