Scientists Discover One of the Longest-Lasting Cases of COVID-19

An international team, including researchers from HSE University, examined an unusual SARS-CoV-2 sample obtained from an HIV-positive patient. Genetic analysis revealed multiple mutations and showed that the virus had been evolving inside the patient’s body for two years. This finding supports the theory that the virus can persist in individuals for years, gradually accumulate mutations, and eventually spill back into the population. The study's findings have been published in Frontiers in Cellular and Infection Microbiology.
Although COVID-19 typically presents as an acute disease, rare cases of persistent, asymptomatic SARS-CoV-2 infection have been documented, most often in immunocompromised patients. Scientists hypothesise that such cases can give rise to dangerous viral variants, defined by the WHO as variants of concern (VOCs).
A team of researchers from Russia, Italy, Switzerland, the UK, and South Africa—including scientists from HSE University—identified a SARS-CoV-2 sample that had accumulated 89 mutations since diverging from its closest known relative. The sample was collected in 2022, while its nearest sequenced neighbour in the phylogenetic tree, obtained in September 2020 and belonging to the B.1.1 lineage, had largely disappeared by 2022. This indicates that SARS-CoV-2 had been persisting, evolving, and accumulating mutations in a single individual’s body for two years—one of the longest documented cases of COVID-19.
Galya Klink
'The sample came from an HIV-positive patient in Kaluga who had never received highly active antiretroviral therapy (HAART). We had only one sample from her, and in theory, it could have been assumed that this was an acute infection caused by a previously unknown coronavirus variant. However, our analysis showed that such a large number of mutations could have accumulated through acute infections only over roughly seven years of viral circulation in the population—longer than SARS-CoV-2 has existed. Using phylodynamic analysis, we established that the patient had already been living with COVID-19 for two years by the time the sample was collected,' explains Galya Klink, Senior Research Fellow of the International Laboratory of Statistical and Computational Genomics at the HSE University Faculty of Computer Science.
The scientists also found that the virus had been evolving three to four times faster than typical SARS-CoV-2 strains; of the 89 mutations detected, 33 occurred in the spike protein, including changes characteristic of variants with increased transmissibility and antibody resistance.
In addition, some of the mutations matched those found in wastewater-derived coronavirus variants. Wastewater analysis is routinely used during periods of rising infections, as it often allows new viral variants to be detected earlier than in the population. The presence of mutations in this sample that are characteristic of wastewater rather than the respiratory tract suggests that the virus may have undergone adaptation to the gastrointestinal tract.
The researchers emphasise that persistent infections are typical in immunosuppressed patients. This highlights the need for close monitoring of such individuals to identify potentially dangerous viral variants in a timely manner.
'Our patient did not infect anyone during the course of her illness. Over time, the sample accumulated mutations that overlapped with those later seen in the Omicron variant, even though Omicron had not yet emerged or spread at that point. This means that the natural selection acting within a single patient differs from that between individuals,' says Klink. 'At the same time, the mutations we observed in the sample support the theory that new, potentially dangerous coronavirus variants can emerge in individuals with weakened immune systems, and that the virus may circulate through different parts of the host’s body.'
See also:
HSE Scientists Use MEG for Precise Language Mapping in the Brain
Scientists at the HSE Centre for Language and Brain have demonstrated a more accurate way to identify the boundaries of language regions in the brain. They used magnetoencephalography (MEG) together with a sentence-completion task, which activates language areas and reveals their functioning in real time. This approach can help clinicians plan surgeries more effectively and improve diagnostic accuracy in cases where fMRI is not the optimal method. The study has been published in the European Journal of Neuroscience.
For the First Time, Linguists Describe the History of Russian Sign Language Interpreter Training
A team of researchers from Russia and the United Kingdom has, for the first time, provided a detailed account of the emergence and evolution of the Russian Sign Language (RSL) interpreter training system. This large-scale study spans from the 19th century to the present day, revealing both the achievements and challenges faced by the professional community. Results have been published in The Routledge Handbook of Sign Language Translation and Interpreting.
HSE Scientists Develop DeepGQ: AI-based 'Google Maps' for G-Quadruplexes
Researchers at the HSE AI Research Centre have developed an AI model that opens up new possibilities for the diagnosis and treatment of serious diseases, including brain cancer and neurodegenerative disorders. Using artificial intelligence, the team studied G-quadruplexes—structures that play a crucial role in cellular function and in the development of organs and tissues. The findings have been published in Scientific Reports.
New Catalyst Maintains Effectiveness for 12 Hours
An international team including researchers from HSE MIEM has developed a catalyst that enables fast and low-cost hydrogen production from water. To achieve this, the scientists synthesised nanoparticles of a complex oxide containing six metals and anchored them onto various substrates. The catalyst supported on reduced graphene layers proved to be nearly three times more efficient than the same oxide without a substrate. This development could significantly reduce the cost of hydrogen production and accelerate the transition to green energy. The study has been published in ACS Applied Energy Materials. The work was carried out under a grant from the Russian Science Foundation.
HSE Strategic Technological Projects in 2025
In 2025, HSE University continued its participation in the Priority 2030 Strategic Academic Leadership Programme, maintaining a strong focus on technological leadership in line with the programme’s updated framework. A key element of the university’s technological leadership strategy is its Strategic Technological Projects (STPs), aimed at creating in-demand, knowledge-intensive products and services.
‘Algebraic Geometry Is the Geometry of Ideal Forms’
Founded 15 years ago at HSE University, the Laboratory of Algebraic Geometry and Its Applications studies fundamental mathematics and helps to shape a unified language of mathematical science. The laboratory has become a well-known and respected research centre; recognition of its achievements includes presentations by its staff at international mathematical congresses and publications in leading global mathematical journals. The HSE News Service spoke with the head of the laboratory, Professor of the Russian Academy of Sciences Dmitry Kaledin, about its work.
HSE Researchers Offer Guidance to Prevent Undergraduate Burnout
Researchers at the HSE Institute of Education have identified how much time students should ideally devote to their studies, extracurricular activities, and personal life to maintain strong academic performance without compromising their mental health. An analysis of responses from 2,753 students, combined with their actual academic results, revealed several risk factors—such as excessive homework—as well as positive factors, including sufficient sleep, regular exercise, and moderate participation in projects. Based on these findings, the researchers developed practical recommendations for both students and universities. The paper has been published in the European Journal of Education.
Scientists Discover Why Parents May Favour One Child Over Another
An international team that included Prof. Marina Butovskaya from HSE University studied how willing parents are to care for a child depending on the child’s resemblance to them. The researchers found that similarity to the mother or father affects the level of care provided by parents and grandparents differently. Moreover, this relationship varies across Russia, Brazil, and the United States, reflecting deep cultural differences in family structures in these countries. The study's findings have been published in Social Evolution & History.
When a Virus Steps on a Mine: Ancient Mechanism of Infected Cell Self-Destruction Discovered
When a virus enters a cell, it disrupts the cell’s normal functions. It was previously believed that the cell's protective response to the virus triggered cellular self-destruction. However, a study involving bioinformatics researchers at HSE University has revealed a different mechanism: the cell does not react to the virus itself but to its own transcripts, which become abnormally long. The study has been published in Nature.
Researchers Identify Link between Bilingualism and Cognitive Efficiency
An international team of researchers, including scholars from HSE University, has discovered that knowledge of a foreign language can improve memory performance and increase automaticity when solving complex tasks. The higher a person’s language proficiency, the stronger the effect. The results have been published in the journal Brain and Cognition.


