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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.

Anti-retroviral drugs are a vital tool in the prevention and treatment of HIV. A new study of pregnant women in Tanzania shows that life-long antiviral treatment also seems to prevent viral transmission from mother to baby. The results of the study, which was conducted in part by researchers at Karolinska Institutet and published in Lancet HIV, make a promising contribution to the WHO’s work with HIV prevention in low and middle-income countries.

Treating severe COVID-19 patients with the anticancer drug bevacizumab may reduce mortality and speed up recovery, according to a small clinical study in Italy and China that was led by researchers at Karolinska Institutet in Sweden between February and April 2020. On average, blood oxygen levels, body temperature and inflammatory markers significantly improved in patients treated with a single dose of bevacizumab in addition to standard care. The research is published in Nature Communications.

The blood is the main source of studies on the immune system, despite the fact that most diseases are combated by immune cells in the body’s tissues. A new study from Karolinska Institutet and the University of Pennsylvania has identified which immune cells patrol the human body’s tissues and circulate back into the blood. The study, which is published in Cell, shows that not all T cells do this – some are found mostly in the blood where they constitute a unique part of our immune system.

Researchers at Karolinska Institutet have led an international team of scientists who have tested a vaccine for Crimean-Congo virus on primates for the first time. The vaccine provided protection against the virus, which can cause fatal haemorrhagic fever, and showed no serious side-effects. The study is published in the journal Nature Microbiology. The next big step will be to test the vaccine on humans.

It is largely unknown why influenza infections lead to an increased risk of bacterial pneumonia. Researchers at Karolinska Institutet have now described important findings leading to so-called superinfections, which claim many lives around the world every year. The study is published in the journal PNAS, Proceedings of the National Academy of Sciences, and can also contribute to research on COVID-19.

Researchers at Karolinska Institutet in Sweden report promising results from an in vitro combination therapy against COVID-19. In a study published in EMBO Molecular Medicine, the researchers show that a combination of remdesivir, an approved drug against COVID-19, and hrsACE2, a medicine currently in phase II trials for COVID-19 treatment, reduced the viral load of SARS-CoV-2 and inhibited viral replication in cell cultures and organoids.

The rheumatoid arthritis drug baricitinib can block viral entry and reduce mortality in patients with moderate to severe COVID-19, according to translational research by an international team coordinated by researchers from Karolinska Institutet in Sweden. The findings, published in the journal Science Advances, support the continuation of ongoing randomized clinical trials.

By screening hundreds of synthetic antibodies, researchers at Karolinska Institutet in Sweden and EMBL Hamburg in Germany have identified an antibody that may prevent the new coronavirus from infecting human cells. The study, which is published in the journal Nature Communications, also shows how antibodies can be quickly produced in the event of future pandemics.

The 2020 Nobel Prize in Physiology or Medicine is awarded for the discovery of the hepatitis C virus. Thanks to the work of the laureates, it is now possible to detect the virus in blood and to provide an effective treatment for the infection. It has saved the lives of millions of people. The prize also focuses on the importance of research into viruses.

A study published in Nature shows that a segment of DNA that causes their carriers to have an up to three times higher risk of developing severe COVID-19 is inherited from Neandertals. The study was conducted by researchers at Karolinska Institutet and Max Planck Institute for Evolutionary Anthropology.

A type of anti-bacterial T cells, so-called MAIT cells, are strongly activated in people with moderate to severe COVID-19 disease, according to a study by researchers at Karolinska Institutet in Sweden that is published in the journal Science Immunology. The findings contribute to increased understanding about how our immune system responds against COVID-19 infection.

More than 10 percent of young and previously healthy people who develop severe COVID-19 have misguided antibodies that attack the immune system itself, and another 3.5 percent carry a specific genetic mutation. This is according to new research published in Science by an international consortium involving researchers at Karolinska Institutet in Sweden.

In a study published in JAMA researchers at Karolinska Institutet and Karolinska University Hospital have examined the association between a positive SARS-CoV-2 test during pregnancy and complications in mothers and their newborn babies. Almost two out of three pregnant women who tested positive for SARS-CoV-2 were asymptomatic and the researchers found no higher prevalence of complications during delivery or of ill-health in the neonates. However, preeclampsia was more common in infected women.

Researchers at Karolinska Institutet have developed a method for fast, cheap, yet accurate testing for COVID-19 infection. The method simplifies and frees the testing from expensive reaction steps, enabling upscaling of the diagnostics. This makes the method particularly attractive for places and situations with limited resources, for repeated testing and for moving resources from expensive diagnostics to other parts of the care chain. The study is published in Nature Communications.

Sweden chose a different pandemic strategy than its peer nations. This included the timing of pandemic-related actions, how parts of the healthcare system reacted to the pandemic, the legal framework for the relationship between the Government and other actors and actions taken with regard to schools. In a paper published in Acta Paediatrica, Professor Jonas F Ludvigsson presents a detailed timeline on how Sweden tackled COVID-19 during the eight months up to 1 September, 2020.

Researchers at Karolinska Institutet in Sweden have identified a small neutralizing antibody, a so-called nanobody, that has the capacity to block SARS-CoV-2 from entering human cells. The researchers believe this nanobody has the potential to be developed as an antiviral treatment against COVID-19. The results are published in the journal Nature Communications.

A blood test on hospital admission showing the presence or absence of SARS-CoV-2 can identify patients at a high risk of severe COVID-19. Admitted patients without virus in their blood have a good chance of rapid recovery. This according to researchers at Karolinska Institutet and Danderyd Hospital in a new study published in the scientific journal Clinical Infectious Diseases.

Researchers may have come one step closer toward understanding how the immune system contributes to severe COVID-19. In a study published in Science Immunology, researchers at Karolinska Institutet in Sweden show that so-called natural killer (NK) cells were strongly activated early after SARS-CoV-2 infection but that the type of activation differed in patients with moderate and severe COVID-19. The discovery contributes to our understanding of development of hyperinflammation in some patients.

A new study from Karolinska Institutet and Karolinska University Hospital shows that many people with mild or asymptomatic COVID-19 demonstrate so-called T-cell-mediated immunity to the new coronavirus, even if they have not tested positively for antibodies. According to the researchers, this means that public immunity is probably higher than antibody tests suggest. The article has been published in the esteemed scientific journal Cell. [This news article has been updated]

A literature review coordinated by Karolinska Institutet in Sweden and McMaster University in Canada demonstrates that cloth face masks provide clinically useful levels of filtration, which has the potential to reduce the spread of viruses such as SARS-CoV-2. The findings, now published in the journal Mayo Clinic Proceedings, support the wearing of cloth masks to reduce the spread of the new coronavirus, according to the researchers.

It is highly likely that children can transmit the new coronavirus, which causes COVID-19, but several factors suggest that children are unlikely to be the main drivers of the pandemic. Opening up schools and kindergartens is unlikely to impact COVID-19 mortality rates in older people, according to a systematic review that spanned 47 publications and was conducted by researchers at Karolinska Institutet. The paper is published in the scientific journal Acta Paediatrica.

Researchers at Karolinska Institutet are coordinating a recently initiated multi-national clinical trial that will evaluate the effect of hyperbaric oxygen treatment (HBO) in severe cases of COVID-19. A total of 200 adults admitted to hospital with moderately severe COVID-19 pneumonia will be recruited. The trial could start as early as next week at a hospital in Region Blekinge, Sweden.

EU-financed Innovative Medicines Initiative (IMI) has boosted funding for research on diagnostics, medicines and vaccines against the new coronavirus SARS-CoV-2. Ali Mirazimi, researcher at Karolinska Institutet and Sweden’s National Veterinary Institute (SVA), coordinates one of eight projects provisionally selected among 144 applicants.

According to many observations, certain virus infections may play a part in the autoimmune attack that leads to type 1 diabetes. Researchers at Karolinska Institutet in Sweden and their Finnish colleagues have now produced a vaccine for these viruses in the hope that it could provide protection against the disease. The study is published today in the scientific journal Science Advances.

Researchers at Karolinska Institutet have together with researchers in China developed a new diagnostic test for COVID-19. The test can be performed without advanced laboratory equipment and deliver the result in about half an hour, according to a study published in the journal Clinical Chemistry. The researchers are now working on verifying the test results on confirmed COVID-19 patients at the Karolinska University Hospital.

A drug already tested against lung disease could potentially inhibit COVID-19 by reducing the coronavirus load that enters the lungs and other organs. That is according to a study in human cell cultures and organoids by researchers at Karolinska Institutet in Sweden and the University of British Columbia (UBC) in Canada, published in the journal Cell.

In a small clinical trial just granted approval, about 30 COVID-19 patients at Karolinska University Hospital may soon begin to receive blood plasma from people who have recovered from the disease. Sweden’s Ethical Review Authority has approved the trial treatment, and its effectiveness will be evaluated in a study by researchers at Karolinska Institutet and the Karolinska University Hospital.

Children infected with the new coronavirus generally have less severe symptoms than adults, they rarely need intensive care and very few child deaths have been reported. This according to a systematic review of COVID-19 in children, based on 45 relevant publications and performed by researchers at Karolinska Institutet. The review is published in the scientific journal Acta Paediatrica.

Researchers at Karolinska Institutet in Sweden and the University of Basel in Switzerland have produced a mathematical model that shows that the spread of the new coronavirus can decline in the summer and then return in the autumn and winter. The analysis has been published in the scientific journal Swiss Medical Weekly.

Karolinska Institutet has launched COVID-19 courses for care providers and medical personnel following a request from the National Board of Health and Welfare. After one week of intense preparation, two online courses are now available.

The human papillomavirus (HPV) causes, amongst other diseases, cancer of the cervix and oropharynx. A Swedish-Finnish study published in The Journal of Infectious Diseases now shows that the most oncogenic HPV types can be eliminated, but only if both girls and boys are vaccinated. Both genders will be offered vaccination in Sweden as of 2020.

Professor Ali Mirazimi at Karolinska Institutet is part of a consortium that has received 1 million Canadian dollars (almost 7 million kronor) to try to develop a drug candidate against COVID-19. Mirazimi will assist with in vitro and in vivo infection models for SARS-CoV-2. The project is a collaboration with Canadian and Chinese researchers.

Karolinska Institutet’s Centre for Research on Health Care in Disasters has been tasked by the National Board of Health and Welfare to arrange an education, training and practice package (e.g. on the handling of personal protective equipment) for medical personnel in connection with the Covid-19 outbreak.

Researchers at Karolinska Institutet are on track to produce a vaccine against the new coronavirus, SARS-CoV-2. Several vaccine candidates are currently available in the freezers at the Department of Laboratory Medicine and the first animal studies are slated to begin at the end of March, according to Professor and Head of Department Matti Sällberg who is leading the effort together with virus researcher and Professor Ali Mirazimi and researcher Gustaf Ahlén.

Three coronavirus projects coordinated by researchers at Karolinska Institutet have moved onto the grant negotiation phase in a bid for 9 million euros (95 million kronor) in EU funding. The projects aim to find a vaccine, immunotherapies and neutralizing antibodies against SARS-CoV-2 and are being coordinated by KI’s Matti Sällberg, Qiang Pan Hammarström and Benjamin Murrell.

Researchers worldwide are trying to develop a vaccine and antiviral treatments against the new corona virus spreading in China. At Karolinska Institutet, virus researchers Ali Mirazimi and Matti Sällberg are working to develop a prototype vaccine against the virus. But vaccine development takes time, and it will likely take at least six to nine months before an application for clinical studies can be filed and another two to three years before a vaccine could be ready for the public.

When Human Immunodeficiency Virus Type 1 (HIV-1) infects a cell, the virus often becomes invisible to both the immune system and drugs. Now research from Karolinska Institutet shows that the integrated virus mimics a specific chromatin structure that lets the virus sequence remain accessible while preventing production of new viruses.

The new corona virus continues to spread despite significant measures taken by the authorities in China to stop the outbreak. However, this time the fast response coupled with increased knowledge about the nature of the virus means the world is better placed to handle the outbreak compared to 18 years ago when SARS caused widespread concern, says virus researcher Ali Mirazimi, adjunct professor at the Department of Laboratory Medicine at Karolinska Institutet.