Information gathering at the beginning of the SEMViD-50 pandemic

In the early phase of the SEMViD-50 pandemic the focus was to recognize the virus and to collect information about its nature. Another important point was the attempt to prevent widespread disease via infection-chains and the warning of people who were at high risk.

Gaining of information

Genomic analysis and molecular characteristics

In order to develop an effective vaccine and potential medications for treating SEMVID as early as possible, researchers placed particular emphasis on sequencing both the viral RNA from plasma and the integrated proviral DNA from host cells. Using blood samples from infected individuals, a group of researchers at ETH Zurich under Prof. Dr. G.Nome completed a comprehensive analysis of the viral genome within a few days, leading to the identification of a new subfamily of retroviruses—the semviruses—which were responsible for the disease.

Protein and Receptor Analyses The pathophysiology of the virus was determined using additional laboratory techniques. Through various protein and receptor analyses at Charité in Berlin, two surface proteins were identified that were found to be responsible, on the one hand, for crossing the blood-brain barrier and, on the other hand, for infecting nerve cells and triggering encephalitis.

Continuous Sequencing and Variant Classification Through continuous sequencing of the viral genome at regular intervals—particularly in severe cases—mutations and variants of the virus were quickly identified, allowing for a timely response. This enabled corresponding adjustments to be made to the vaccine to provide the broadest possible coverage against all variants. The variants were classified using the Greek alphabet to provide a structured and consistent overview.

Clinical and Epidemiological Data Collection

Patient interviews and follow-up examinations With regard to the first reported severe cases of encephalitis in southern Switzerland among a group of young academics on a hiking trip, interviews were conducted with the patients and their immediate social circle. This revealed a common thread in their various recreational activities, particularly a hiking trip. Using cross-hospital data collection systems from emergency departments, the incidence of encephalitis in other locations was closely monitored, confirming a significant increase in the disease. Tick bites were quickly identified as the cause among the young patients, after which TBE or other similar diseases were initially blamed for the symptoms. Within a few weeks, however, this diagnosis was proven to be incorrect, and the novel SEMViD was identified as the actual cause of the disease.

Analysis of blood donations and organ transplants (screening, Red Cross) A few weeks after the unusual cluster of encephalitis cases in southern Switzerland was reported, further reports of severe disease progression emerged in Germany as well. In these cases, however, no tick bite could be identified as the cause, prompting intensive investigations into possible contacts. These cases proved to be particularly fatal, as nearly all of those affected died from encephalitis within a very short time. These were individuals who were already seriously ill and required blood transfusions as part of their treatment. As a result, the donated blood units were examined more closely, and it was determined that the donors were members of the hiking group in southern Switzerland in question, although they had not developed any symptoms despite being bitten by ticks. Based on this finding, the route of transmission for the viral infection was expanded to include blood-to-blood transmission. As a result of this tragic turn of events, strict regulations on blood donations were immediately implemented, which in turn led to a massive shortage of these products.

Monitoring of Mucosal Transmission and Partner Screening Despite strict monitoring of blood donation systems and intensified tick screening measures, an ever-increasing number of cases was recorded in the summer of 2050. This led scientists to suspect that the virus had likely undergone a mutation, enabling it to spread through other mechanisms as well. Through questionnaires and rigorous contact tracing of affected individuals, a cluster of cases within intimate partnerships was quickly identified. As a result, the transmission routes were expanded to include mucosal contact, such as sexual intercourse, which in turn contributed significantly to increased stigmatization of the disease.

Assessment of Perinatal Risks (Miscarriages, Birth Defects) As a result, increased attention was focused on assessing the perinatal risks associated with infection in pregnant women. Particularly among infected women in the first trimester, a number of miscarriages were recorded, caused by severe damage to the developing central nervous system. For this reason, pregnant individuals were urged to exercise particular caution regarding potential sources of infection and were informed through their treating gynecologists and informational brochures. For fetuses born with birth defects, a possible infection during the last two trimesters of pregnancy was ruled out postnatally by conducting an antibody screening test on the newborn.