COVID-19 case cluster study

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The COVID-19 case cluster study (Covid-19 case cluster study) - often referred to in the media as the Heinsberg study - is a study published on May 4, 2020 about the spread and course of the SARS-CoV-2 triggered COVID-19 pandemic in Gangelt .

The study was initiated by the state government of North Rhine-Westphalia together with the Heinsberg district and the Institute for Virology at the University of Bonn . It is headed by the director of the institute Hendrik Streeck . The state government is co-financing the study.

The study was published to the public from April 6 to 12, 2020 by the Berlin PR agency StoryMachine on Facebook and Twitter as the Heinsberg protocol and HEINSBERG PROTOCOL. marketed.

background

In the district of Heinsberg , the first major spread of the COVID-19 pandemic in Germany was caused - probably as a result of a carnival session in Gangelt , in which an infected couple took part . The pandemic has appeared in the Heinsberg district since February 27, 2020 with a high number of cases (infections and deaths) across Germany as part of the COVID-19 pandemic, with superspreading events playing a role. In Germany, Heinsberg is regarded as the “first region” and “epicenter” of the pandemic. Since March 6, 2020, the Robert Koch Institute ( RKI ) has listed the Heinsberg district as a “particularly affected area in Germany”.

study

aims

The study is to examine lethality , unreported numbers and immunity with regard to SARS-CoV-2 and give recommendations for action.

Action

The study began on March 30, 2020 and was designed to last four weeks. Around 600 households were asked to participate in a serial letter . A total of around 1,000 residents from around 400 households took part by April 8, 2020.

There are questionnaires filled in throat swabs taken and blood for the presence of antibodies tested. An ELISA antibody test from Euroimmun was used for this.

Intermediate results

The first results of the study were published on April 9, 2020 via Facebook and Twitter. The data on 509 people were included in this first analysis. An existing immunity of about 14% of the participants was determined, about 2% of the people had a current SARS-CoV-2 infection, the infection rate was about 15% and the "case fatality rate" related to the According to the preliminary data from this study, the total number of infected people in the Gangelt community is around 0.37%. This value is to that of the Johns Hopkins University determined naive Confirmed case-dead-share ( English naive confirmed case fatality rate ) compared which would have been at the time 1.98%, which lie on a good 5-fold level. This difference results from the fact that the Heinsberg study aims to map an infected / deceased proportion by selecting the infected as a sample, i.e. a mortality based on the total number of infected people, while the Johns Hopkins University obtained a quota of confirmed deaths calculated on the confirmed cases , with unclear test surveys and high numbers of unreported cases . Referred to in the pre-release mortality of Johns Hopkins University is in the literature as a naive case-dead-share ( English naive case fatality rate , called) because they do not take into account the systemic distortions in an ongoing epidemic; the numbers of the different estimates of the lethality naive case deceased content ( English naive case fatality rate ), case-dead portion ( English case fatality rate ), and infected-dead portion ( English infection fatality rate ) (deaths per infected) differ in principle and can therefore not be equated, but are often confused.

The data - according to Streeck - showed that most infections did not take place in restaurants or supermarkets, but in places with "a lot of singing and dancing".

In a press conference on April 9, 2020 with the Prime Minister of North Rhine-Westphalia, Armin Laschet , Streeck recommended that politicians enter phase 2 of the assessment by the German Society for Hospital Hygiene, i.e. start with the removal of the restrictions on the population.

Results

On May 4, 2020, Hendrik Streeck, Gunther Hartmann and co-authors presented further results in a pre-publication. Of 919 people from 405 randomly selected households in Gangelt, 138 had tested positive for antibodies (15.02%). Statistically corrected IgG values ​​showed an infection rate of 15.5%. Seven people had died of COVID-19, which, when projected, results in an infected-deceased proportion (IFR), which in contrast to the case-deceased proportion (CFR) also includes asymptomatic cases, of 0.36% ( confidence interval 0.29%) up to 0.45%). Based on the IFR values ​​in Gangelt and the number of officially 6575 COVID-19 deaths in Germany (data from the Robert Koch Institute on May 2, 2020), the authors say that there is an estimated number of 1.8 million infected people in Germany . As the authors themselves restrict, if the survey period had been extended beyond April 6, the IFR would have been 0.41, since another person died of COVID-19 by April 20. In addition, with regard to the portability of the IFR data, the authors noted that the association with the carnival event could also have influenced the IFR, as both the risk of infection and the number of symptoms were higher in people who were at a carnival event. One possible explanation is a higher viral load from speaking and singing louder at meetings.

22% of those infected said they had no symptoms at all. The risk of infection in households of one to four people did not depend on the number of people. Contrary to expectations, the study also found a relatively moderate increase in the secondary risk of infection with the number of people in the household: from the basic risk of infection of 15.5%, it rose for two people in the household to 43.6% for the second person and for three people in the household Household for the second and third person to 35.7% each and with four people in the household for the second, third and fourth person to 18.3% each. The cause is unknown, but according to the authors it is possibly due to the fact that the other household members have acquired a certain immunity that is not reflected in the ELISA tests. In households with at least one infected “child under the age of 18”, the probability of infection of the other people in the household was 66.6% in three-person households and 33.3% in four-person households.

financing

The state government of North Rhine-Westphalia is funding the study with 65,315 euros. The public relations work is financed separately by at least three companies in the private sector with more than 60,000 euros, more than half of it by StoryMachine itself. Hendrik Streeck expects the total cost of the study to be around 250,000 euros, which would mainly be paid with funds from the participating university institutes, which 65,315 euros from the state of North Rhine-Westphalia did not even cover the material requirements.

public relation

Logo of the study on Facebook and Twitter

The study was accompanied by the PR agency StoryMachine from April 6 to 12, 2020 with ten employees. Unusually for a scientific study, numerous contributions were posted on Facebook and Twitter. Philipp Jessen, former Stern.de boss and managing director of the agency, which otherwise does not appear publicly, said that the aim was "to enable this scientific work to be as public and visible as possible."

The public relations work of StoryMachine - founded by Kai Diekmann , Jessen and Michael Mronz - is not financed by the state of North Rhine-Westphalia. According to Mronz, the agency does not receive any money from tax revenues or from the Bonn University Hospital. Instead, according to Jessen , StoryMachine will receive 30,000 euros from two companies - Deutsche Glasfaser and Gries Deco Holding - for the project and take care of the rest. Mronz has been known to Streeck "privately" for a long time. The SPD politician Sarah Philipp criticized this constellation as an “unfair competitive advantage” because Streeck had awarded the contract to Mronz. The science journalist Joachim Müller-Jung commented that Streeck had given a technically completely unskilled marketing agency "Propaganda-Prokura". The German Council for Public Relations is investigating the role of the agency for possible violations of the transparency requirement.

In contrast, it became known that StoryMachine advertised potential co-financiers of the project by saying that the aim of the study support was to create a narrative to relax the sanctions. So stated u. a. Annette Leßmöllmann , the impression arose that the results were known beforehand and that efforts were made to convey the following message to the public: "The easing of the lockdown is a good thing and we will provide you with facts". That is a promise that "science cannot actually make". According to the magazine Kontraste , Prime Minister Armin Laschet also made several false statements about the PR work accompanying the course. In mid-April, Laschet repeatedly expressed ignorance about the accompanying PR work and still said on April 19 that he did not know "which PR agency does what, whether it will be accompanied, whether Mr Streeck will be helped, to answer press inquiries from all over the world in a coordinated manner ". The state government did not know anything about PR support for the study. In fact, Laschet was informed about the PR activities of Storymachine for the study at the beginning of April.

Regarding the criticism of the monitoring of the study by StoryMachine , Streeck said: “We made our support clear and transparent from the very first moment. [...] In the interests of maximum transparency towards the public, I gladly accepted this offer and coordinated it with the management of the university hospital. "

reception

Intermediate results

After the interim results were announced, the method and informative value of the study as well as the roles of Prime Minister Laschet and StoryMachine were criticized.

scientist

Christian Drosten , professor and institute director at the Charité in Berlin, criticized the study and Streeck's recommendations. If an unsuitable antibody test was used, there would be a high rate of false-positive results for technical reasons. In addition, Drosten continued, he could not deduce anything from the presentation given due to the lack of explanations. Streeck replied: “Of course, that ultimately has to be decided by politics. We provide data and facts. ”Streeck is a member of a group of experts in North Rhine-Westphalia that advised politicians and made recommendations on easing the restrictions.

Drosten also said that a value of 0.37% mortality per case of infection roughly corresponds to what was already assumed in preliminary considerations with politicians and scientists weeks before the introduction of the contact blocks. He questioned the stated rate of 15% immunity; one has to see whether these are detailed diagnoses or just laboratory tests, which often show false positive and require confirmatory examinations in the laboratory. He asked for clarification as to whether these tests had taken place in order to correctly translate the figures for the political and public.

Alexander Kekulé , professor at the Martin Luther University Halle-Wittenberg , described the study as a “special case” in his podcast in an initial statement and advised to be careful with recommendations based on the study. With regard to lethality, he said that the number was in the range that was expected. In 31 studies to date with a total of 53,631 positive cases, the result is a very weak evidence-based estimate of around 0.3% with a 95% confidence interval of 0.0% to 1.0%.

Gérard Krause, epidemiologist at the Helmholtz Center for Infection Research , initially criticized the fact that all people in the selected households were tested and included in the calculations. One should “by no means take all the results from these households and convert them to percentages, but at most one person per household.” Later he corrected himself to the effect that in his original statement he had not specifically referred to the Heinsberg study, “but to general aspects in studies of this kind. "He had spoken to one of the participants in the study and saw" no reason to suspect or even to assume failures in the epidemiological methodology. "

Simon Clarke, a microbiologist at the University of Reading , points out that the thesis that the presence of antibodies proves immunity has not been confirmed. David Heymann from the London School of Hygiene and Tropical Medicine points out the possibility of false-positive antibody tests and raises concerns that it is premature to postulate herd immunity based on experience with immunity with other coronaviruses . Keith Neal, Professor Emeritus of Epidemiology, on the other hand, comments on the study as a good sign that the mortality rate from the disease is lower than previously assumed, but also points out that the results depend on the quality of the antibody test used.

Christiane Woopen , herself a member of the NRW Expert Council, criticized Streeck in a talk show for his recommendations, since "ultimately, no political recommendations for action can be drawn from the interim results of a study." At the press conference on April 9, 2020, she “even joined the Expert Council pronounced against it ”. Streeck was "very surprised about the statement made by Ms. Woopen (...) because the expert council never discussed when we would present the interim results." There were also no specifications "how and when a publication should take place."

Politician

Several prime ministers, the Federal Minister of Economics Peter Altmaier and Chancellor Angela Merkel warned against hasty steps and warned not to be reckless. NRW Prime Minister Laschet discussed the study on April 15, 2020 with the Federal Chancellor and the heads of the other state governments. A group of experts set up by Laschet, which includes Hendrik Streeck, Udo Di Fabio , Christiane Woopen and Christoph M. Schmidt , had suggested “gradually re-permitting individual areas of public life and controlling containment measures in a more differentiated manner”, including schools and universities and retail. Earlier, on April 14, 2020, he and the responsible state ministers announced the opening of schools and day-care centers from April 20 and 27, respectively. The heads of government decided on different dates.

Journalists

Kathrin Zinkant noted in the Süddeutsche Zeitung that the one-and-a-half- page press release accompanying the announcement of preliminary results did not meet the criteria for a scientific pre-publication (“preprint”).

In a detailed analysis, Christian Schwägerl and Joachim Budde reconstructed the entire complex of the study, its initiation, the entanglement with the accompanying media campaign by StoryMaschine , the personal motives of Streeck, his role in the expert committee of NRW Prime Minister Laschet and the reception of the social media The media, the press conference and the “interim report” (as put in quotation marks by the authors) followed the campaign. The authors quoted Annette Leßmöllmann , holder of the chair for science communication at the Karlsruhe Institute of Technology, with the words: "PR and journalism are mixed together extremely skilfully." And further reported that the makers of the Heinsberg Protocol , i.e. the StoryMachine , changed hands on Easter Sunday 6 p.m. on Twitter had tentatively said goodbye to their audience, punctually “at the end of the lockdown-easing offensive of the North Rhine-Westphalian Prime Minister”.

Results

scientist

Christian Drosten said that no raw data from the confirmed antibody test could be found in the manuscript, “not only the ELISA, the initial values, but also the confirmation by the neutralization test.” The authors did, but did not include the results in the evaluation. He is not sure "whether you can just do it like that, convert everything so directly to nationwide registration numbers." He believes there are effects that were not taken into account in the rough calculations.

Gérard Krause described the study as a "very good starting point"; extrapolation to Germany is "difficult" because of the low number of deaths.

Journalists

Stephan Sahm , Christoph Sahm and journalists from the SWR criticize the fact that a number of 1.8 million infected people in Germany could not be derived from the study. The study contained statistical errors. With a 95% confidence level , the upper limit would be 0.7% infection mortality , almost double the value given in the study. Based on the study, mortality in Germany can only be estimated with great uncertainty. However, this is not what the study's authors have shown. The authors of the study rejected this criticism: The number of 1.8 million infected people is clearly shown as an example calculation, an estimate of the death rate in all of Germany is not the subject of the study. Therefore, this criticism misses the goals of the work.

Scientific work in context

With regard to the test system used in the Heinsberg study, questions about reliability were raised. Regarding the cross-reactivity in question, Streeck stated in an interview that the manufacturer of the antibody test used had previously checked it on 1,600 sera from blood donors. In this case, false positive test results should have been found in the event of cross-reactivity, since approx. Five to ten percent of the population were already infected with coronaviruses other than Sars-CoV-2. However, since this was apparently only the case to a very small extent, the manufacturer stated the specificity with more than 99 percent.

A study by Christian Drosten's research group, which was provisionally published on March 20, 2020, found cross-reactivity to the common cold virus HCoV OC43 in a validation of a prototype of the commercial ELISA system used in the Heinsberg study . Whether the test was so advanced at the time of the Heinsberg study that this cross-reactivity could be reduced or even ruled out is unclear based on time estimates .

A study by Fudan University in Shanghai, published on April 6, 2020, examined 175 patients who had survived COVID-19 with regard to their antibody formation using ELISA and a subsequent neutralization test . The authors came to the conclusion that there was no measurable antibody formation in 10 patients and only a low, quantitatively measurable antibody response was present in around a third of the patients. On the basis of the data collected, the authors questioned the regular development of antibody-mediated immunity in mild cases and recommended further investigations. The neutralization test is the gold standard in medical virology for determining protective and thus immunity-inducing antibodies.

On April 10, 2020, a prior publication reported further cross-reactions of the ELISA system. When comparing several commercial test systems, the Euroimmun-ELISA stood out due to cross-reactions with antibodies against, among others, adenoviruses and the human coronavirus HKU1 . Cross-reactivity increased with the presence of multiple cold virus antibodies in the blood samples.

The Robert Koch Institute announced three studies in Germany. During the examinations, blood samples should be examined for antibodies.

Web links

Individual evidence

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