According to current understanding, infection with SARS-CoV-2 represents a hazard to all parts of the population, including the young and healthy. However, this is particularly true for people suffering from certain health conditions, especially cardiovascular disease. Besides the lungs, SARS-CoV-2 can inflict severe damage to the heart, even in patients without any pre-existing condition. In some patients, the initial signs of the infection are cardiovascular symptoms such as heart palpitations or tightness in the chest, rather than fever and cough. This is reason for the researchers at the VIVIT to get involved and develop a thorough understanding of this disease.
The so-called SARS-CoV-2 virus belongs to the family of coronaviruses, which can infect animals and humans. Four of these coronaviruses have been endemic in humans for decades or centuries. An estimated 30% of all common colds are caused by one of these four coronaviruses, and up to 90% of all adults show antibodies against them in their blood, in keeping with previous infections. However, SARS-CoV-2 had been confined to animals until very recently and transited to humans only a few months back. Hence, the human immune system has not encountered it in the past.
Coronaviruses store their genetic information in form of an RNA molecule, which they transfer to the human cell upon infection. In contrast to HIV, which gets stably incorporated into the human genome, coronaviruses don’t integrate. Hence, after the illness is over, coronaviruses disappear from the body, but antibodies remain detectable in the blood for a long time and provide immunity against re-infection.
Drugs and Vaccines
Currently there are no drugs aimed specifically at SARS-CoV-2. But a number of drugs that have been developed to treat other diseases have the potential to be effective against SARS-CoV-2 (Lopinavir/Ritonavir, Ribavirin, Remdesivir, Chloroquine, Camostat Methylat, …). Some of these are already being used in the most severe cases of COVID-19, the disease caused by SARS-CoV-2. Scientists are working at full speed to develop a vaccine against SARS-CoV-2. Currently, 15 vaccine candidates are being tested worldwide. How much time it will take for a vaccine to become available depends on the outcome of the respective trials, the scale-up of production, and on the regulatory process of granting market approval. While calling for a fast roll-out of novel treatment options, drugs and vaccines, it should not be forgotten that 28% of Austrians smoke and only 8% make use of an influenza vaccine.
Testing for SARS-CoV-2
There are three types of laboratory diagnostic methods for the detection of a SARS-CoV-2 infection: sequencing, PCR (polymerase chain reaction), and ELISA (enzyme-linked immunosorbent assay). Sequencing deciphers the complete viral genome and provides information about mutations of the virus and allows the path of its spread to be reconstructed. PCR is by far the most widely used method and currently the standard protocol. It is based on the detection of short, highly specific fragments of the virus’ genome, isolated from throat swabs. However, laboratory capacities in Vorarlberg and in Austria and the whole of Europe, are limited. Population-wide testing, let alone repeated testing, is not feasible. From an epidemiological standpoint, if the virus keeps spreading, at some point the identification of hotspots such as Lombardy, Madrid, and Tyrol, and of local clusters such as Arlberg and Nenzing will lose its significance. Once it comes to that, it makes sense to limit testing to high risk patients and to simply regard young patients with typical clinical symptoms but without comorbidities as corona cases, without further testing. In the medium term, laboratory diagnostic practice will shift from PCR to ELISA. The latter does not test for the virus itself but for the immune response to it by detecting antibodies in the blood of patients. At an advanced stage of the pandemic, ELISA offers critical advantages over PCR. It allows high-throughput testing and provides information about a history of SARS-CoV-2 infection, even when symptoms have subsided and the virus itself can no longer be detected. This is particularly important in mildly symptomatic and asymptomatic patients to find out whether they have encountered the virus or not. A positive result means the person is already immune to the virus and in most cases quarantine and home isolation are no longer needed. This information is of outmost importance in doctors and health care personnel. In the long-term, antibody detection by ELISA can be used to validate the effectiveness of a vaccine. Moreover, sample collection for ELISA is a lot less error-prone than for PCR (blood vs. throat swabs).
We urge people to stay away from DIY-testing kits that are currently entering the global market. Their sensitivity, i.e. the ability for them to detect an infection with high reliability and not yield a false-negative result, is often poor. The resulting false sense of security could spell great danger. In Vorarlberg, testing for SARS-CoV-2 is carried out at the pathology department of the State Hospital in Feldkirch (LKHF). Due to their specific qualification and vast expertise, members of the VIVIT have been called in to support the team on site. With great personal commitment, they work alongside staff of the pathology department to keep up with the growing demand for testing. In parallel, the abovementioned ELISA method is being implemented to enable testing for the level of immunity in the population. The current dramatic situation in some countries shows how important it is to have a robust health care system and scientific capabilities and how vital it is to have experts and research institutes in Vorarlberg.