The scientific journal " British Journal of Haematology " published the article "Immunogenicity and clinical effectiveness of mRNA vaccine booster against SARS-CoV-2 Omicron in patients with haematological malignancies: A national prospective cohort study" by scientists from Vilnius and Cambridge Universities, which was prepared using health data provided by the State Data Agency.

The main goal of the study was to determine laboratory indicators that allow doctor to predict the risk of developing a severe COVID-19 disease caused by the omicron strain (coronavirus infection) in a patient with a malignant blood disease. By tracking the levels of antibodies directed against the coronavirus SARS-CoV-2 after vaccination, the researchers observed that patients with antibody levels above 500 BAU/ml had a less than 1 per cent risk of severe coronavirus infection. However, almost every fifth patient with an antibody concentration below 20 BAU/ml developed a severe form of the COVID-19 disease. Since the detection of antibodies is a relatively simple and widespread laboratory method, the results of a study based on it by scientists help doctors to select patients with the most impaired immune system function. Such persons are at risk of serious complications of the coronavirus disease (COVID-19). They may need hospitalization or additional help to fight the virus, for example, an antiviral drug should be prescribed as early as possible.

The researchers also sought to find out whether the third (booster) dose of the messenger RNA (mRNA) vaccine provides additional protection against the currently widespread omicron variant of SARS-CoV-2. Because the original Pfizer-BioNTech vaccine (Comirnaty) was directed against the first strain of the Wuhan virus, its effectiveness in protecting against the genetically altered omicron strain has been questioned. However, when comparing patients vaccinated with two and three doses of the vaccine, the researchers found that after the booster dose of the vaccine, the number of all infections caused by the omicron strain and the number of serious infections were reduced by 45 and 73 per cent respectively. This shows that booster doses improve anti-infectious immunity that is affected by a blood disease or its treatment.

"First of all, we would like to thank the State Data Agency team for excellent communication and all kinds of help. We knew exactly what to do and how to get access to health data. We were introduced to the main functionalities of the information system used by the State Data Agency, and we quickly received answers to questions that arose during the data analysis process. The data provided is well structured, it was easy to filter and use it on the Agency's statistical platform. A notable drawback is the longer than expected data loading and structuring time. Furthermore, the data use platform was not as user-friendly as it would have been, so the data analysis took time," the researchers share their cooperation experience with the State Data Agency.

The researchers point out that in most similar studies, infection cases were collected through a survey or using a single hospital (center) data registry. Consequently, some cases were lost or could be identified biasedly. One of the main advantages of this study is that receiving data from the State Data Agency allowed the registration of cases of the COVID-19 disease throughout the country. According to the researchers, the opportunity to get access to the national database significantly expands the possibilities of conducting large-scale scientific studies in Lithuania.