Predominance of influenza B/Yamagata lineage viruses in Bulgaria during the 2017/2018 season.

In this study, we investigated the antigenic and genetic characteristics of influenza viruses circulating in Bulgaria during the 2017/2018 season. The detection and typing/subtyping of influenza viruses were performed using real-time RT-PCR. Results of antigenic characterisation, phylogenetic and amino acid sequence analyses of representative influenza strains are presented. The season was characterised by the predominance of B/Yamagata viruses, accounting for 77% of detected influenza viruses, followed by A(H1N1)pdm09 (17%), B/Victoria (3.7%) and A(H3N2) (2.4%). The sequenced B/Yamagata, B/Victoria, A(H1N1)pdm09 and A(H3N2) viruses belonged to the genetic groups 3, 1A, 6B.1 and 3C.2a1, respectively. Amino acid analysis of B/Yamagata isolates revealed the presence of three changes in haemagglutinin (HA), eight changes in neuraminidase (NA) and a number of substitutions in internal proteins compared with the B/Phucket/3073/2013 vaccine virus. Despite the amino acid changes, B/Yamagata viruses remained antigenically related to the vaccine strain. B/Victoria isolates fell into a group of viruses with double deletion (Δ162-163) in HA1. Substitutions in HA and NA sequences of B/Victoria, A(H1N1)pdm09 and A(H3N2) viruses were also identified compared with the vaccine strains, including in antigenic sites. The results of this study confirm the genetic variability of circulating influenza viruses and the need for continual antigenic and molecular surveillance.

Th17 cells in Bulgarian children with chronic obstructive lung diseases.

INTRODUCTION AND OBJECTIVES: Th17 lymphocytes are now widely believed to be critical in various chronic pulmonary diseases. However, there is still a small number of investigations regarding children. We aimed to assess the percentage of Th17 lymphocytes and IL-17A in peripheral blood of children with chronic obstructive lung diseases. PATIENTS AND METHODS: We included a total of 42 children: 20 with bronchial asthma (BA), 12 with cystic fibrosis (CF) and 10 healthy children without a history of allergies, aged 4-17 years. Th17 cells (CD3+CD4+CD161+CCR6+) were determined in peripheral blood by flow cytometry. The concentration of serum IL-17A was measured by ELISA. RESULTS: The BA patients had a significantly higher percentage of Th17 (12.40±1.16%) compared to the CF children (7.64±0.87%, p=0.0035) and healthy (7.25±0.45%, p=0.008). Stratifying the BA group, we found higher levels of Th17 in patients with severe BA (p=0.03), whereas patients with moderate BA had Th17 cells close to those in CF and healthy children. We found that patients with better control of BA had Th17 closer to those with CF (p=0.98) than BA children with poor control (p<0.001) (post hoc, Bonferroni correction). CF patients with concomitant P. aeruginosa infection showed slightly higher percentages of Th17 cells than those without infection (8.08±3.09% vs. 6.25±2.42%, p=0.294). CONCLUSIONS: The percentage of Th17 cells was significantly increased in the peripheral blood of children with severe BA compared to the children with moderate BA, which suggests that the former could possibly benefit from future target therapies.

Paediatric pneumococcal disease in Central Europe.

Streptococcus pneumoniae causes considerable global paediatric morbidity and mortality, despite the availability of safe and effective pneumococcal conjugate vaccines (PCVs). To justify the introduction of PCVs, accurate information on the burden of disease is required. Here, we present an appraisal of the pneumococcal epidemiological situation in 11 Central European countries. The data are based on study findings presented at the 12th Central European Vaccine Advisory Group (CEVAG) meeting, held on 21-22 May 2010 in Sofia, Bulgaria, and a literature review of the PubMed database using the search terms 'pneumococcal' or 'Streptococcus pneumoniae', in combination with 'otitis media', 'pneumonia', 'meningitis' or 'bacteraemia/sepsis', and '[Central European country name]'. The incidence of pneumococcal disease appears to be lower in Central Europe than previously reported for Europe as a whole, with the highest risk in infants aged 0-2 years. The fatality rates in the under fives from invasive infections are up to 40%. A paucity of comprehensive country-specific data on pneumococcal disease burden arises from the lack of homogenous surveillance programmes. Standardised, active surveillance systems are required for the accurate evaluation of the pneumococcal disease burden in the region. Only then can the need for vaccination be addressed.

[Diagnostic importance of the cytologic examination of tracheal lavage fluid in high-risk newborn infants].

UNLABELLED: Aim of the study is to find out early diagnostic markers of chronic lung disease (CLD) in the tracheal lavage fluid (TLF) of high-risk neonates using the cytologic examination. MATERIAL AND METHODS: TLF from forty newborn infants treated by conventional ventilation (CV) and oxygen were studied. The infants were divided into three groups: I--12 term and 11 premature infants without signs of CLD on the 28th day of birth; II group--15 premature infants with persistent respiratory distress and oxygen dependence till the 28th day of life without signs of CLD after 36 weeks of gestation and III group--5 premature infants treated by CV more than 14 days with signs of CLD after 36 weeks of gestation. The diagnostic tracheal lavage (TL) was performed between the 4th and 10th day from the beginning of CV. A standart method for TL of neonates was used. The cytologic samples were prepared from filtrated TLF and examined by light microscopy. The percentage count of blood cell elements and the ratio between normal and metaplastic bronchoepithelial cells were determined and compared between the three groups. RESULTS: We found similar mean values of the cellular elements and the ratioes of the term and the preterm babies from I group: alveolar macrophages (AM)--75.8 +/- 11.35%; neutrophils (Neu)--22.78 +/-10.8%; lymphocytes (Ly)--1.1 +/- 0.32% and ratio between normal and metaplastic (N/M ratio) epithelial cells = 3,17:1. In the II group the mean value of Neu was 31.57 +/- 9.2%, which is higher than the Neu mean value of the I group, but the difference is not significant (p = 0.2). The mean value of AM was 65.7 +/- 9.8% and the of as well as between I and II group (p < 0,05) and between II and III group (p < 0.05). CONCLUSION: The percentage of the metaplastic respiratory cells in TLF has an early diagnostic value for CLD in high-risk newborn infants: metaplasia in less than 40% of the epithelial cells can be accepted as transitional, since it is reversible; mataplasia between 40% and 80% of the cells is associated with a risk of broncho-obstructive syndrome in early infancy. Squamous metaplasia of more than 80% of the cells in TLF has a diagnostic importance for CLD.

Protective, elective lung irradiation in non-metastatic Ewing's sarcoma.

Ewing's sarcoma in childhood is a disease from family of the peripheral primitive neuroectodermal tumours. For a period of 16 y (1984-2000), 34 children with Ewing's sarcoma were treated and followed in our department. Twenty-seven of these patients were without distant metastases. Complex treatment was applied to all these patients-chemotherapy VACA (vincristine, actinomycin D, cyclophosphamide, adriamycin), local radiotherapy to a total dose of 50-56 Gy +/- surgery. After, a local tumour control was achieved in 11 children with non-metastatic Ewing's sarcoma, elective whole lung irradiation to a total dose of 12-15 Gy was applied. Our experience in these 11 patients with non-metastatic Ewing's sarcoma, in whom elective lung irradiation was applied, showed significant reduction in the lung metastases, improved free of disease survival and overall survival. The achieved good treatment results necessitate extending this treatment approach through defining the risk groups of patients, suitable for elective lung radiotherapy combined with chemotherapy in non-metastatic Ewing's sarcoma.