The COVID-19 mRNA BNT163b2 Vaccine Was Well Tolerated and Highly Immunogenic in Young Adults in Long Follow-Up after Haematopoietic Stem Cell Transplantation.

Sixty five patients (18-31 years) who had received allogeneic haematopoietic stem cell transplantation (3-27 years from HSCT) were evaluated for the tolerance and immunogenicity of the COVID-19 mRNA BNT163b2 vaccine. Methods: Patients were vaccinated with two doses at 5 weeks interval. After each dose, patients completed a survey concerning adverse events (AE) and anti-SARS-CoV-2 IgG antibodies were measured before the first vaccine dose (1stVD) and 14-21 days after the second dose (2ndVD). AE reported after 1stVD and 2ndVD, respectively were: fever 0%, 1.7%; fatigue 15.4%, 25.8%; headache 15.4%, 24.1%; chills 6.1%, 12.0%; muscle pain 15.4%, 24.1%; joint pain 3.0%, 6.9%; nausea 6.1%, 6.9%; pain at injection site 30.7%, 34.4%; swelling 3.0%, 10.3%; redness 0, 3.4%; pruritus 0, 5.2%; and axillary lymphadenopathy 3.0%, 1.7%. After 2ndVD, 96.5% patients were positive for anti-SARS-CoV-2 (GMC 3290.94 BAU/mL). No correlation presented between the antibody titer and symptoms of chronic Graft-versus-Host disease, total IgG, lymphocyte CD4+, or AE. Significantly higher titers were observed in COVID-19 convalescents, and inverse correlation (R2 = -0.0925, p = 0.02) between the time from HSCT and titers after 2ndVD was present. Conclusions: The young adults after HSCT tolerate the COVID-19 mRNA vaccine well and show immunologic response.

Mumps, measles and rubella vaccination in children with PFAPA syndrome.

There is no published data regarding immunologic response to vaccinations in children with PFAPA syndrome (periodic fever, aphthous stomatitis, pharyngitis and cervical adenitis). The aim of this study was to evaluate mumps, measles and rubella immunity in children with PFAPA. 31 children with PFAPA syndrome and 22 healthy children (control group - CG) were recruited to the study. All children were previously vaccinated with one dose of MMR vaccine according to the Polish obligatory vaccination schedule. The patients from both groups were evaluated for anti-measles, anti-mumps and anti-rubella IgG antibodies concentrations (ELISA tests; the reference values for protective antibody levels were 150IU/L, 16RU/L and 11IU/ml respectively). The percentage of patients with protective antibodies levels was as follows: measles - 93.55% of PFAPA and 95.45% of CG patients (p=0.77); mumps - 74.19% of PFAPA and 95.45% of CG patients (p=0.02); rubella - 80.65% of PFAPA and 90.9% of CG patients (p=0.30). CONCLUSIONS: Children with PFAPA syndrome present a good response to the measles and rubella component of the MMR vaccine, however immunity against mumps after one dose of MMR may not be sufficient. Further investigation concerning immunity against vaccine-preventable diseases and the safety of vaccinations in children with periodic fever syndromes is required.

[Study on genetic diversity of genes encoding main adhesins among nontypeable Haemophilus influenzae strains isolated from children in Poland]. / Badania profilu determinant genetycznych kodujacych glówne adhezyny bezotoczkowych szczepów Haemophilus influenzae izolowanych od dzieci w Polsce.

The study was based on hypothesis that in the nontypeable population of H. influenzae strains isolated from children there are some genetically predisposed to induce symptomatic infection in children and that they might be divided into different groups depending on profiles of genes encoding main adhesins synthesis. The work aimed at analysis of distribution of genes encoding adhesins and evaluation of domination possibility of some strains representing particular adhesins genes profiles among NTHi population. Results of the study revealed that among population of NTHi strains, distribution of genes encoding main adhesins are differing. Among children, NTHi strains harbouring genes encoding HA and HMW1/HMW2 adhesins were more prevalent in healthy children and in children with symptomatic infections, respectively. Analysis of strains harbouring main adhesins profiles might be a useful screening method in monitoring strains circulating among children, in order to determine the most invasive NTHi strains.

[Diagnostic difficulties in identification of Haemophilus influenzae colonising the nasopharynx of children]. / Problemy diagnostyczne przy identyfikacji szczepów Haemophilus influenzae kolonizujacych jame nosowo-gardlowa dzieci.

The frequency of capsulated or non-capsulated Haemophilus influenzae strains colonisation among children attending day-care centres or orphanages has been studied. Detection of capsulated or non-capsulated H. influenzae strains has been compared for agglutination test and PCR. Misdiagnosing of H. influenzae serotype with agglutination found in the study suggest that the frequency of Hib strains colonizing the nasopharynx might be lower that previously evaluated. Due to perspectives of the wider use of Hib Immunisation in the future, more efficient diagnosis scheme for identification/differentiation of capsulated and non-capsulated H. influenzae strain should be undertaken.

[Transmission of Haemophilus influenzae type b strains among children attending day-care centers and orphanages]. / Badania transmisji szczepów Haemophilus influenzae typu b krazacych w populacji dzieci w przedszkolach i domach dziecka.

Goal of the work was to evaluate the differences level among H. influenzae strains of b serotype isolated from children attending day-care centres and orphanages and among strains isolated from invasive infections. In the work PFGE in Hib strains transmission examination and for epidemiological studies among three sources of invasive infection was applied. Among 35 Hib strains tested and control strain 8 different pulsotyped were found. Among 21 strains colonising the nasopharynx of healthy children, and among 13 Hib strains isolated from cerebrospinal fluid, 6 and 1 pulsotypes were found, respectively. Results obtained show that healthy children might be colonizing with genotypes characteristic for Hib strains isolated from invasive infections. In this view wider Hib vaccination seems be expected, as Hib circulation is common.

Comparison of usefulness of randomly amplified polymorphic DNA and amplified-fragment length polymorphism techniques in epidemiological studies on nasopharyngeal carriage of non-typable Haemophilus influenzae.

Randomly amplified polymorphic DNA (RAPD) and automated amplified-fragment length polymorphism (AFLP) techniques with fluorescently labelled primers were used to type non-serotypable Haemophilus influenzae (NTHI) isolates. Eighty-seven isolates from healthy children attending day-care centres or living at orphanages in southern Poland were investigated. Through comparison of the AFLP data with RAPD analysis, it has been concluded that the discriminatory power of AFLP for NTHI typing is higher than RAPD. Generally, the NTHI isolates analysed were highly heterogeneous, as detected with a HindIII/TaqI AFLP genotyping scheme on intra/inter similarity levels of 94 and 96 % using Pearson's correlation coefficient. The range of similarity values found for isolates from children permanently residing at a particular day-care centre was much wider than that for isolates from orphanages. AFLP can efficiently access NTHI strain diversity and can monitor their turn-over for comparative typing in local and inter-local epidemiological investigations.