Interferons (IFNs) are cytokines released by host cells in response to the presence of pathogens or tumor cells. The aim of this review was to present the previously known and new findings about the role of interferons type I and II, and recently discovered type III in Mycobacterium tuberculosis (M. tuberculosis) infection control. Infection of various cell types with M. tuberculosis induce both IFN-α and IFN-β synthesis. The majority of the studies support the findings that IFN type I actually promotes infection with M. tuberculosis. It has been well establish that IFN-γ has protective function against M. tuberculosis and the other mycobacteria and that the primary source of this cytokine are CD4(+) and CD8(+) T cells. Recently, it has been shown that also the innate lymphocytes, γδ T cells, natural killer (NK) T cells, and NK cells can also be the source of IFN-γ in response to mycobacterial infection. Several studies have shown that CD4(+) T cells protect mice against M. tuberculosis independently of IFN-γ. The balance between IFN-γ and different cytokines such as IL-10 and other Th2 cell cytokines is likely to influence disease outcome. Type I IFN appears to be detrimental through at least three separate, but overlapping, type I IFN-mediated mechanisms: induction of excessive apoptosis, specific suppression of Th1 and IFN-γ responses, and dampening of the immune response by strong IL-10 induction. Recently it has been found that M. tuberculosis infection in A549 lung epithelial cells stimulate up-regulation of IFN-λ genes in vitro. IFN-λs also have a role in modulation of Th1/Th2 response. IFN-λs are not essential for M. tuberculosis infection control, but can give some contribution in immune response to this pathogen.

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In humans, there are three members of type III interferon family, designated as IFN-k1 (IL-29), IFN-k2 (IL-28A) and IFN-k3 (IL-28B). Bacterial infections, including Mycobacterium tuberculosis infection, trigger the expression of interferon I and II genes, but little is known about their effect on IFN-k genes. It has been found that M. tuberculosis infection in A549 lung epithelial cells stimulate upregulation of IFN-k2 genes in vitro. The aim of this study was to determine the IFN-k2 levels in sputum of patients with active pulmonary tuberculosis comparing with levels in healthy persons sputum and sputum of persons with latent tuberculosis. IFN-k2 level in the samples was quantified with sandwich enzyme-linked immunoassay kit for quantization of human IFN-k2 (IL-28A). The IFN-k2 level in sputum of patients with pulmonary tuberculosis was significantly higher comparing with IFN-k2 levels in healthy group (P = 0.001) and latent tuberculosis group (P = 0.005). Logistic regression analysis has shown that IFN-k2 level in sputum is related to culture result (OR = 4.14; 95% CI = 1.28-17.5; P = 0.019). There was the correlation between Bartlett score and IFN-k2 levels in group with pulmonary tuberculosis (r = 0.641; P < 0.01).In conclusion, we have found that the inflammatory cells in sputum can be source of IFN-k after receptor stimulation by M. tuberculosis components.

Calluna vulgaris L. Hull (Ericaceae) has been used for treatment of urinary tract infections in traditional medicine. In this study we analyzed in vitro antibacterial activity of the plant extracts on different strains of Escherichia coli, Enterococcus faecalis and Proteus vulgaris, as well as the concentrations of total phenols and flavonoids in the extracts. Minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were determined. The concentrations of total phenols were examined by using Folin-Ciocalteu reagent and ranged between 67.55 to 142.46 mg GAE/g. The concentrations of flavonoids in extracts were determined using spectrophotometric method with aluminum chloride and the values ranged from 42.11 to 63.68 mg RUE/g. The aqueous extract of C. vulgaris showed a significant antibacterial activity. The values of MIC were in the range from 2.5 mg/ml to 20 mg/ml for this extract. Proteus vulgaris strains were found to be the most sensitive. The results obtained suggest that all tested extracts of C. vulgaris inhibit the growth of human pathogens, especially the aqueous extract.

The aim of the study was to assess the seroprevalence of SARS-CoV-2 in the Republic of Srpska, Bosnia and Herzegovina, and to analyse the knowledge, attitudes and practices of the population toward COVID-19. This population-based study was conducted in a group of 1,855 randomly selected individuals from all municipalities from 1 December 2020 to 15 January 2021. All individuals were asked to sign a consent form and to fill in a questionnaire, following which a blood samples were collected. Total anti-SARS-CoV-2 antibodies were determined in serum specimens using the total Ab ELISA assay. The overall seroprevalence rate was 40.3%. Subjects aged <65 years were 2.06 times more likely to be seropositive than those aged ≥65, and 30% of seropositive individuals presented no COVID-19 symptoms. The household members of seropositive individuals were 2.24 times more likely to develop COVID-19 symptoms than the household members of seronegative individuals. More than 95% of respondents believe that preventive measures are very important to control the infection transmission. Majority of respondents wear the masks properly, maintain the required physical distance whenever possible and wash hands with soap. Nearly 50% of individuals were of the opinion that the vaccine could prevent the infection. This study showed that an overall SARS-CoV-2 seropositivity rate by the middle of January 2021 was very high. Attitudes and practices regarding the COVID-19 indicate that additional efforts should be taken in order to improve the health education with a focus on preventive measures and vaccination.

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Healthcare workers (HCW) in primary healthcare centres in the Republic of Srpska, Bosnia and Herzegovina, are on the first combat line with COVID-19. This study aimed to assess the seroprevalence of SARS-CoV-2 among HCW at the primary healthcare centres and to analyse the risk exposure to COVID-19, clinical signs and vaccination status. A cross-sectional study was conducted among HCW at the selected primary healthcare centres between 19 March and 30 April 2021. Antibodies against the SARS-CoV-2 virus were detected by enzyme-linked immunosorbent assay (ELISA). A total of 1,023 HCW (mean age 45 years; 71% female) were included in the study. The anti-SARS-CoV-2 antibodies were detected in 69.5% of all participants. There was a significant difference in seropositivity among primary healthcare centres from different geographical regions. As many as 432 (42%) of all participants had confirmed COVID-19 symptoms before the study and, 84.8% of them were seropositive. This study showed that 702 primary HCW were vaccinated with any of these vaccines: Sputnik V, Sinopharm, Pfizer/Biontech. High titre of SARS-CoV-2 antibodies was found amongst those who received one (92.6%) or both (97.2%) doses of vaccines. In this study, we report high prevalence of SARS-CoV-2 antibody among HCW in primary healthcare in the Republic of Srpska, Bosnia and Herzegovina during the third pandemic wave.

Introduction:During the last two and a half years, severe acute respiratory syndrome coronavirus 2 (sars-Cov-2) infection has spread around the world. Most of the sars-Cov-2 vaccines are designed to produce anti-sars-Cov-2 immunoglobulin G (igG) against the viral s-glycoprotein. The aim of this study was to measure the anti-s antibody titres among the medical personnel who had been fully vaccinated with different types of vaccines, and to compare them with those who were CoviD-19 convalescents.Material and methods: in this study serum was collected from 261 healthcare workers, of whom 227 were vaccinated, while 34 were recovered participants who were not immunised. serum samples were collected 21 days after the first dose and 60 and 180 days after the second dose of the vaccines and tested with a commercial eLisa kit.Results: The highest antibody level (12 aU/ml) was measured in the Pfizer-BionTech group, followed by sinopharm (9.3 aU/ml), sputnik v (5.9 aU/ml), sinovac (4.6 aU/ml) and oxford/astra-Zeneca vaccine (2.5 aU/ml) 60 days after the second dose of the vaccines (90 days after the first dose). The seropositivity rate for mrna vaccine was 88.5%, for vector vaccines 86.2% and for inactivated vaccines 71.4%. When comparing these antibody levels with CoviD-19 convalescents, higher antibody titres were found in vaccinated participants (5.76 aU/ml vs 7.06 aU/ml), but the difference was not significant (p = 0.08).Conclusions: individuals vaccinated with mRNa and vector vaccines had a higher seroconversion rate compared to the group vaccinated with inactivated vaccines, or convalescents.