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During the pandemic, it became clear that children who contracted COVID-19 became less ill than adults. One hypothesis has been that common colds would give children immunity protecting against a severe form of the disease. Researchers at Karolinska Institutet are now able to show that OC43, one of the coronaviruses that cause common colds, boosts the immune response to COVID-19. The study, which is published in PNAS, could give rise to more tailored vaccine programmes for children and adults.

Katie Healy at the Department of Dental Medicine and Sebastian Ols at the Department of Medicine in Solna, receive the Sven Gard's scholarship 2023. Sven Gard's scholarship is awarded annually for the best dissertation in virology. The scholarship takes place as a result of nomination.

High levels of mucosal IgA antibodies in the airways protect against SARS-CoV-2 infection for at least eight months. Omicron infection generates durable mucosal antibodies, reducing the risk of re-infection. These are the findings of a study published in The Lancet Infectious Diseases by researchers at Karolinska Institutet and Danderyd Hospital in Sweden. The results raise further hope for the feasibility of future nasal vaccine platforms to protect against infection.

Losing too much weight when infected with COVID-19 has been linked to worse outcomes. Now, researchers at Karolinska Institutet have discovered that SARS-CoV-2 infection fuels blood vessel formation in fat tissues, thus revving up the body’s thermogenic metabolism. Blocking this process by using an existing drug curbed weight loss in mice and hamsters that were infected with the virus, according to the study published in the journal Nature Metabolism.

Antiviral drugs almost completely reduce the risk of mothers passing on HIV infection to their children, even in a low-income country with a high HIV incidence such as Tanzania, according to a new study in The Lancet HIV by researchers from Karolinska Institutet. The discovery raises hopes of achieving the World Health Organization’s goal of eliminating the spread of infection from mother to child.

The risk of being infected by parvovirus is elevated in those people who have blood group Rh(D), according to a study published in The Journal of Infectious Diseases by researchers from Karolinska Institutet in collaboration with Octapharma.

Researchers at Karolinska Institutet have shown that patients with acute COVID-19 infection have increased levels of the cytokine IL-26 in their blood. Moreover, high IL-26 levels correlate with an exaggerated inflammatory response that signifies severe cases of the disease. The findings, which are presented in Frontiers in Immunology, indicate that IL-26 is a potential biomarker for severe COVID-19.  

The Committee for Research at Karolinska Institutet has decided on recipients from the Jonas Söderquist scholarship foundation for basic research in virology and immunology 2022. Quirin Hammer at the Department of Medicine, Huddinge (MedH) and Daniel Sheward at the Department of Microbiology, Tumor- and Cell Biology (MTC)) are awarded.

A study at Karolinska Institutet shows that the coronavirus variant BA.2.75.2, an Omicron sublineage, largely evades neutralizing antibodies in the blood and is resistant to several monoclonal antibody antiviral treatments. The findings, published in the journal The Lancet Infectious Diseases, suggest a risk of increased SARS-CoV-2 infections this winter, unless the new updated bivalent vaccines help to boost immunity in the population.

Many people were delighted to hear that Professor Svante Pääbo has been awarded the 2022 Nobel Prize in Physiology or Medicine, particularly so Hugo Zeberg, researcher at Karolinska Institutet. He has collaborated with Svante Pääbo for years, not least on the work to find Neanderthal genes that can influence how ill different people become after contracting the COVID-19 virus.

Intravenous treatment with omega-3 fatty acids in elderly hospitalised patients in intensive care due to COVID-19 seems to have positive effects on the ability of the immune system to cope with the virus, according to a study from Karolinska Institutet. In the future, the study, published in the journal Clinical and Translational Medicine, could lead to a complementary, cost-effective treatment for COVID-19.

On September 27 a minisymposium will be arranged in association with the 2022 Nicholson lecture with focus on COVID-19 and the immune response against SARS-CoV-2

Children with certain immunodeficiency diseases carry mutations in genes that regulate the body’s immune system against viral infections and they have a higher mortality rate due to COVID-19. This is according to a study by researchers from Karolinska Institutet, published in the Journal of Allergy and Clinical Immunology.

High levels of mucosal antibodies in the airways reduce the risk of being infected by omicron, but many do not receive detectable antibodies in the airways despite three doses of the SARS-CoV-2 vaccine. These are the findings of a study published in The New England Journal of Medicine, led by researchers at Karolinska Institutet and Danderyd Hospital.

In a recent study researchers from Karolinska Institutet, among others, have characterised the new omicron variant BA.2.75, comparing its ability to evade antibodies against current and previous variants. The study, published in the journal The Lancet Infectious Diseases, suggests that BA.2.75 is not more resistant to antibodies than the currently dominating BA.5, which is positive news.

Researchers at Karolinska Institutet are developing a coronavirus vaccine designed to be less sensitive to mutations and equipped for future strains. The vaccine showed promising results in mice in a newly published study in EMBO Molecular Medicine, and the researchers now hope to be able to take it to safety studies on humans.

In a new analysis, Karolinska Institutet is ranked number eight in a list of organizations with the most published articles on COVID-19 and the immune response. KI also stands out as one of the universities that has had the most international collaborations in the field. The analysis was conducted by Chinese researchers without a connection to KI and is published in the journal Frontiers in Public Health.

Researchers at Karolinska Institutet present the results of a refined clinical COVID-19 test, which has been used to track the spread of the Omicron variant in real time in the Swedish population. The study, published in the journal Med, provides new insights into the dominance transition of Omicron sublineages that occurred consistently across the world.

Researchers at Karolinska Institutet and Danderyd Hospital have followed participants who have received three doses of the SARS-CoV-2 vaccine and compared their immune responses after Omicron infection. The results, which are published in The Lancet Infectious Diseases, show that Omicron infection elicits significantly higher antibody responses in individuals without prior COVID-19 infection as compared to previously infected individuals.

Researchers at Uppsala University and Karolinska Institutet are one step closer to explaining why COVID-19 patients have a substantially increased risk of blood clots. The study, published in Nature Immunology, shows that a gene variant in the innate immune system influences the risk for blood clots in the lungs of severely ill COVID-19 patients.

Vaccines based on inactivated SARS-CoV-2 virus are commonly used in resource-poor countries due to their low cost. New research from Karolinska Institutet shows that a booster shot of mRNA vaccine to individuals who have received two doses of inactivated vaccine offers the same level of protection against COVID-19 as three doses of mRNA vaccine. The findings are published in the journal Nature Communications.

A team of scientists including at Karolinska Institutet has used mini-kidneys simulating those of diabetic patients to further our understanding of the link between diabetes and COVID-19. The researchers found that diabetic mini-kidneys have a higher susceptibility to SARS-CoV-2 infection than non-diabetic mini-kidneys. The study, which is published in the journal Cell Metabolism, also identified genetic evidence for the essential role of the ACE2 receptor in COVID-19.

Maike Winters at the Department of Global Public Health, is awarded for her thesis "Contagious (Mis)Communication: the role of risk communication and misinformation in infectious disease outbreaks".

Residential exposure to ambient air pollutants is linked to an elevated risk of SARS-CoV-2 infection, an observational study of young adults in Stockholm, Sweden shows. The study was conducted by researchers from Karolinska Institutet and is published in JAMA Network Open.

The Svedberg prize 2022 is awarded to Ben Murrell, Department of Microbiology, Tumor and Cell Biology, for his work characterizing antibody responses to viruses, especially the virus SARS-CoV-2.

Researchers at Karolinska Institutet have developed a novel strategy for identifying potent miniature antibodies, so-called nanobodies, against emerging SARS-CoV-2 variants. The approach led to the discovery of multiple nanobodies that in cell cultures and mice effectively blocked infection with different SARS-CoV-2 variants. The findings, which are described in the journals Nature Communications and Science Advances, could pave the way for new treatments against COVID-19.

Vaccination against COVID-19 during pregnancy is not associated with a higher risk of pregnancy complications, according to a large-scale registry study from Karolinska Institutet in Sweden and the Norwegian Institute of Public Health published in the journal JAMA.

Late last year, preliminary studies revealed that the fast-spreading Omicron SARS-CoV-2 variant was likely to evade COVID-19 antibodies but, in many people, less so than expected. Now one of those studies from Karolinska Institutet has been published in the prestigious journal The Lancet Infectious Diseases. KI researcher Ben Murrell explains the findings and recalls the rush to understand the new variant.

People who were bedridden for at least a week due to COVID-19 were more likely to experience anxiety and depression for up to 16 months after the infection, compared with those who only had mild symptoms or were never infected. That is according to a large study based on data from six countries and conducted by an international team of researchers including those from Karolinska Institutet and the University of Iceland. The findings are published in The Lancet Public Health.

There is a lack of understanding as to why some people suffer from long-lasting symptoms after COVID-19 infection. A new study from Karolinska Institutet in Sweden, the Helmholtz Center Munich (HMGU) and the Technical University of Munich (TUM), both in Germany, now demonstrates that a certain type of immune cell called macrophages show altered inflammatory and metabolic expression several months after mild COVID-19. The findings are published in the journal Mucosal Immunology.

The EU-funded research network Vaccelerate has now opened a European volunteer-registry of study participants for research on COVID-19 vaccines. The aim of this initiative is to boost the capacity for clinical studies on COVID-19 vaccines in the EU, but also to support vaccine research in future pandemics.

Little has been known to date about how the immune system’s natural killer (NK) cells detect which cells have been infected with SARS-CoV-2. An international team of scientist led by researchers from Karolinska Institutet now shows that NK cells respond to a certain peptide on the surface of infected cells. The study, which is published in Cell Reports, is an important piece of the puzzle in our understanding of how the immune system reacts to COVID-19.

Hopefully we are nearing the end of the pandemic. But the virus is still there and scientists expect that new variants may emerge. Making us more sick, however, is not on the viral agenda.

The omicron variant can partly evade the antibody response provided by vaccination or infection with previous variants of SARS-CoV-2. However, T cells still recognise omicron, scientists at Karolinska Institutet report in a study published in the journal Nature Medicine.

An international metastudy led by researchers at Karolinska Institutet has identified a specific gene variant that protects against severe COVID-19 infection. The researchers managed to pinpoint the variant by studying people of different ancestries, a feat they say highlights the importance of conducting clinical trials that include people of diverse descents. The results are published in the journal Nature Genetics.

KI researcher Marcus Buggert has been awarded the prestigious ERC Starting Grant for his research on human cell-mediated immunity against virus diseases. In all, the European Research Council through this call will invest EUR 619 million in 397 young research leaders.

Researchers at Karolinska Institutet have charted the number of healthcare workers in Stockholm who were on duty during the first wave of the pandemic despite being infected with SARS-CoV-2, having been asymptomatic at the time. The results of the study, which is published in the journal PLOS ONE, present very low figures but the researchers believe that this could still have affected the spread of infection.

The risk of adverse pregnancy outcomes in women who tested positive for SARS-CoV-2 is likely lower than several earlier studies have suggested, a national study of all pregnant Swedish women tested for SARS-CoV-2 between March 2020 and January 2021 reports. The study, published in BJOG: An International Journal of Obstetrics and Gynaecology and led by researchers at Karolinska Institutet, shows that the association varies widely depending on the routines used for testing pregnant women.

Researchers at Karolinska Institutet have analysed the presence of SARS-CoV-2-specific antibodies and memory cells of the immune system in young adults. The results, published in The Journal of Allergy and Clinical Immunology, show that over one in four had antibodies due to the infection. Fewer of these individuals had measurable levels of memory B and T cells compared with other age groups. The researchers will now study long COVID in young adults and the effects of vaccination on immunity.

Antibodies in the airways quickly wane after SARS-CoV-2 infection, but vaccination results in a strong increase in antibody levels, especially after two doses, according to a new study from Karolinska Institutet published in the journal JCI Insight. The results suggest that having a second dose of vaccine also after recovering from COVID-19 may be important for protecting against re-infection and to prevent transmission.

During the pandemic, it has become evident that people with cardiovascular disease and obesity are at much higher risk of developing very severe, even fatal COVID-19 disease. Researchers at Karolinska Institutet have identified some metabolic processes that SARS-CoV-2 uses to attack lung tissue. The results, which are published in Molecular & Cellular Proteomics, could one day be used to treat COVID-19, and potentially for other viruses like the Crimean-Congo hemorrhagic fever virus and HIV-1.

COVID-19 disease severity seems to be affected by the characteristics of white blood cells called granulocytes, which are part of the innate immune system. Combined measurements of granulocytes and well-known biomarkers in the blood can predict the severity of the disease, according to a new study from Karolinska Institutet. The results are published in the journal PNAS and may eventually contribute to more tailored treatments for COVID-19 patients.

In March 2020, thousands of researchers across the globe joined forces to answer the question of why some COVID-19 patients develop a severe, life-threatening disease, while others manage with mild or no symptoms. A comprehensive summary of their findings to date, based on the analyses of nearly 50,000 patients and published in Nature today, reveals 13 genetic regions that are strongly associated with infection or severe COVID-19.

Researchers at Karolinska Institutet have developed a technology for cost-effective surveillance of the global spread of new SARS-CoV-2 variants. The technique is presented in the scientific journal Nature Communications.

The human papillomavirus (HPV) can cause cancer and many countries run national vaccination programmes to minimise the risk. Studies involving researchers at German Cancer Research Center, Karolinska Institutet and Tampere University now report on the longitudinal effect of common HPV vaccines. The results, which are published in The Journal of Infectious Diseases and Lancet Infectious Diseases, show lasting protection against more HPV variants than the vaccines were developed for.

Researchers at Karolinska Institutet and the Public Health Agency of Sweden have studied newborn babies whose mothers tested positive for SARS-CoV-2 during pregnancy or childbirth. The results show that although babies born of test-positive mothers are more likely to be born early, extremely few were infected with COVID-19. The study, which is published in the esteemed journal JAMA, supports the Swedish recommendation not to separate mother and baby after delivery.

A study involving researchers at Karolinska Institutet and IMBA – Institute of Molecular Biotechnology of the Austrian Academy of Sciences – demonstrates how zika and herpes viruses can lead to brain malformations during early pregnancy. The researchers used 3D models of human brains to study which mechanisms are involved in virus-induced microcephaly, a condition where babies are born with smaller-than-usual heads. The results are published in the journal Cell Stem Cell.

An international consortium that includes researchers at Karolinska Institutet has developed a ‘double antibody’ that targets two different sites of the SARS-CoV-2 virus, thereby preventing the virus from mutating to resist the therapy. A study published in the scientific journal Nature shows that the antibody potently neutralises SARS-CoV-2 and its variants and protects against COVID-19 in mice.

Researchers at Karolinska Institutet are investigating the efficacy and safety of COVID-19 vaccines in a new study on patients with compromised immune systems, who can become seriously ill if they are affected by COVID-19. On February 23, the first patient in the study was vaccinated with an mRNA vaccine at Karolinska University Hospital. So far, the project has received two grants from the Knut and Alice Wallenberg Foundation of SEK 10 million in total.

Last year, researchers at Karolinska Institutet and the Max Planck Institute for Evolutionary Anthropology in Leipzig, Germany showed that a major genetic risk factor for severe COVID-19 is inherited from Neandertals. Now the same researchers show, in a study published in PNAS, that Neandertals also contributed a protective variant. Half of all people outside Africa carry a Neandertal gene variant that reduces the risk of needing intensive care for COVID-19 by 20 percent.