High vaccine confidence and strong approval of the mandatory immunization schedule among Bulgarian general practitioners in 2022.

In a context of recently decreasing childhood immunization coverage and low uptake of COVID-19 vaccines in Bulgaria, this study measures vaccine hesitancy among general practitioners (GPs) in the country, as they are central to forming patients' attitudes. In 2022, a face-to-face survey was conducted through a simple random sample from an exhaustive national database of Bulgarian GPs. This study measured attitudes on vaccine importance, safety, and effectiveness, and attitudes toward the Bulgarian immunization schedule. Information was collected on demographic and GP practice characteristics and possible predictors of vaccine confidence in order to test for associations with attitudes toward immunization. GP attitudes toward vaccines and the immunization schedule in Bulgaria were generally positive. Among 358 respondents, 351 (98%,95%CI96-99%) strongly agreed/agreed that vaccines are important, 352 (98%,95%CI96-99%) that vaccines are effective, and 341 (95%,95%CI93-97%) that vaccines are safe. 347 respondents (97%,95%CI95-98%) affirmed that "it's good that vaccines from the children's immunization schedule are mandatory", and 331 (92%,95%CI89-95%) agreed with the statement "Bulgaria's childhood immunization has my approval". Trust in information from official institutions was among the strongest predictors of vaccine confidence. Respondents' vaccine confidence levels are within the ranges reported by GPs in other European countries and above those reported within the general Bulgarian population. GPs' vaccine confidence is highly associated with trust in official institutions. It is important to maintain trust in official institutions and to support GPs in communicating vaccine knowledge with patients so that vaccine hesitancy in the general population is countered.

Bulgarian General Practitioners' Communication Styles about Child Vaccinations, Mainly Focused on Parental Decision Making in the Context of a Mandatory Immunization Schedule.

The communication practices of general practitioners in relation with vaccines have not been a topic of wide scientific interest. In this article, we outline them in the context of Bulgaria. A representative, cross-sectional, quantitative, face-to-face survey was conducted among 358 Bulgarian general practitioners in 2022 using simple random sampling. We conducted an exploratory factor analysis using questions about the role of the GPs, which measure models of communication. Based on the factor analysis, we distinguished four communication styles. They were called: active communicator, restrictive communicator, informing communicator, and strained communicator. One-way ANOVA and the T-test were carried out to explore the connections between factor scores (communication styles) and other variables. One of the most important results in the study was that the informing physician (emphasizing the choice of the parents) was the most common model in Bulgaria. This is somewhat contradictory, because of the mandatory status of most vaccines. We found connections between the communication styles and other variables-such as the type of settlement, having a hesitant parent in the practice, recommendations of non-mandatory vaccines, and experience with vaccine-preventable diseases. On the basis of the factor analysis and analysis of relationships with other variables, we reached the conclusion that in Bulgaria, hesitant parents are not sufficiently involved in active, effective communication about vaccines by GPs.

Features of Mpox infection: The analysis of the data submitted to the ID-IRI network.

Background: Mpox is a rare zoonotic disease caused by the Mpox virus. On May 21, 2022, WHO announced the emergence of confirmed Mpox cases in countries outside the endemic areas in Central and West Africa. Methods: This multicentre study was performed through the Infectious Diseases International Research Initiative network. Nineteen collaborating centres in 16 countries participated in the study. Consecutive cases with positive Mpoxv-DNA results by the polymerase chain reaction test were included in the study. Results: The mean age of 647 patients included in the study was 34.5.98.6% of cases were males, 95.3% were homosexual-bisexual, and 92.2% had a history of sexual contact. History of smallpox vaccination was present in 3.4% of cases. The median incubation period was 7.0 days. The most common symptoms and signs were rashes in 99.5%, lymphadenopathy in 65.1%, and fever in 54.9%. HIV infection was present in 93.8% of cases, and 17.8% were followed up in the hospital for further treatment. In the two weeks before the rash, prodromal symptoms occurred in 52.8% of cases. The incubation period was 3.5 days shorter in HIV-infected Mpox cases with CD4 count <200/µL, we disclosed the presence of lymphadenopathy, a characteristic finding for Mpox, accompanied the disease to a lesser extent in cases with smallpox vaccination. Conclusions: Mpox disseminates globally, not just in the endemic areas. Knowledge of clinical features, disease transmission kinetics, and rapid and effective implementation of public health measures are paramount, as reflected by our findings in this study.

Detection of measles virus in Bulgaria from 2012 to 2018.

AIM: To determine the circulation patterns of measles virus in Bulgaria from 2012 to 2018 after a large measles outbreak in the country (2009-2011). METHODS: Three types of clinical material were collected: serum samples, urine samples, and nasal swabs. Enzyme-linked immunosorbent assay (ELISA) was used to detect specific viral immunoglobulin (Ig) M/IgG antibodies. Viral RNA was extracted from all urine and nasal swabs. RESULTS: In the investigated period, 102 patients were confirmed to have measles (age range: two months to 55 years). A total of 101 samples (99%) were measles-IgM positive. Most of them were detected in 2017 (73%, 74/101), when a measles outbreak in the country was reported. The majority of patients were unvaccinated children aged under 13 months. Out of 101 measles serum samples confirmed by ELISA, 18 (20.45%) were measles-IgG positive and 15 (17.05%) were borderline. Thirty-three positive PCR products were sequenced and genotyped. In 2013, 2016, 2017, and 2018, three different measles viral genotypes were detected: D8, H1, and B3. Most patients were unvaccinated or insufficiently vaccinated. CONCLUSION: Preventive measures are indispensable to limit the infection in different regions of Bulgaria and its spread to other countries. As vaccination coverage against measles and other vaccine-preventable infections, including SARS-Co2, is low, it is necessary to perform molecular identification of viruses to monitor their circulation and pathogenicity.

Measles Virus and Subacute Sclerosing Panencephalitis.

BACKGROUND: Subacute Sclerosing Panencephalitis (SSPE) mainly affects children and young people. It is a rare, chronic progressive degenerative form of cerebral inflammation with various infectious noxa, which develops for years after a primary, uncomplicated infection, and the highest percentage can be caused by measles virus and in rare cases by rubella. The aim of the present study is to investigate in the laboratory the role of measles virus in the development of neurological symptoms and diseases of the CNS. METHODS: A total of 46 clinical materials (23 sera samples and 23 CSF) obtained from 23 patients with neurological symptoms and diagnoses: "SSPE" (in 10 patients) and "Encephalitis" (in 13 patients), in the period January 2011 - December 2020 were tested in the National Reference Laboratory (NRL) "Measles, mumps and rubella" at National Centre of Infectious and Parasitic Diseases (NCIPD), Sofia, Bulgaria. Serological (indirect ELISA test for the detection of specific measles IgG/IgM antibodies in serum samples and cerebrospinal fluid) and molecular (RT-PCR for the demonstration of viral RNA) methods were used. RESULTS: The study was performed by parallel testing of serum samples and CSF from each patient. Positive results for measles IgG antibodies in sera were found in 21 patients. Presence of measles IgG antibodies in CSF was demonstrated in four children with diagnosis SSPE (two children at 4 years, one child at 4 years and 6 months, and one at 11 years old). All children with positive laboratory results for SSPE had evidence of MeV infection before 2 years of age. The patients with SSPE had high antibody titers (CSF > 230 U/mL) in their CSF. Patients with positive anti-Measles IgG in the CSF were also found to have positive results for protective measles IgG in the serum samples and their IgG titers were nearly twice as high compared to other patients' sera. The presence of specific measles IgM antibodies was not demonstrated in the tested specimens. RT-PCR test was performed for all samples, and the presence of viral RNA was not detected. CONCLUSIONS: The measles infection can be a reason for developing serious complications affecting CNS in all age groups. SSPE itself is extremely difficult to diagnose, which is why laboratory confirmation of any clinical case is a necessary condition for effective disease surveillance.

Clinical significance and role of coinfections with respiratory pathogens among individuals with confirmed severe acute respiratory syndrome coronavirus-2 infection.

Introduction: This study aimed to determine the prevalence, viral profile, and clinical features of coinfections with severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) and other respiratory viruses. Methods: Nasopharyngeal samples and clinical data of 221 hospitalized patients and 21 outpatients were collected and analyzed. Real-time reverse transcription-polymerase chain reaction was used to detect SARS-CoV-2, influenza virus, respiratory syncytial virus (RSV), human metapneumovirus (HMPV), parainfluenza virus (PIV) 1,2,3, rhinovirus (RV), adenovirus (AdV), bocaviruses (BoV), and seasonal coronaviruses (OC43, 229E, NL63, and HKU1). Viral load was determined by capillary electrophoresis. Results: From November 2020 to mid-March 2022, 242 SARS-CoV-2 positive patients were tested for seasonal respiratory viruses, and 24 (9.9%) cases of coinfections were detected. The distribution of viruses involved in cases of coinfections were as follows: HMPV (n = 6; 25%), RSV (n = 4;16.7%), AdV (n = 4; 16.7%), BoV (n = 4; 16.7%), PIV3 (n = 2; 8.3%), influenza A (H3N2; n = 2; 8.3%), RV (n = 1; 4.62%), and RV+BoV (n = 1; 4.62%). The proportion of detected coinfections with SARS-CoV-2 was highest in children aged 0-5 years (59%), followed by those >65 years (33%). In specimens with detected coinfection, the viral load of influenza was higher than that of SARS-CoV-2, and the mean viral load of SARS-CoV-2 was higher than that of the other respiratory viruses. C-reactive protein (CRP) and lymphocytes count in co-infected patients >65 years of age were on average higher than in children <16 years of age (mean CRP of 161.8 ± 133.1 mg/L; 19.7 ± 3.09% vs. mean 6.9 ± 8.9 mg/L, 0.9 ± 3.1%; p < 0.01). Patients >65 years of age co-infected with SARS-CoV-2 and other respiratory viruses had longer hospital stays than those <16 years of age (mean 9 ± 3.96 days vs. 5.44 ± 1.89 days; p = 0.025). The combination of AdV and SARS-CoV-2 is fatal for patients aged >65 years. Conclusion: In patients aged >65 years, coinfection with SARS CoV-2 and other respiratory viruses, together with concomitant diseases, causes worsening of the clinical picture and complications, and can be fatal. Screening of patients with SARS CoV-2 for other respiratory viruses is needed to select appropriate treatments and prevent a fatal outcome of the disease.

Primate Erythroparvovirus 1 Infection in Patients with Hematological Disorders.

Primate erythroparvovirus 1, commonly referred to as Parvovirus B19 (B19V), is a DNA virus that normally results in a mild childhood infection called "erythema infectiosum". Besides respiratory spread, B19V can also be transmitted through transfusions, which may result in persistent anemia in immunodeficient hosts. Dialysis patients often face acute or chronic anemia after infection with B19V. Here, we describe the laboratory investigation of 21 patients with hematological disorders for B19V infections. B19V DNA was detected in 13 (62%) of them, with specific IgM antibodies in three of the DNA positives. All 13 patients received treatment and were laboratory-monitored over a period of one year. In only two patients (a 14-year-old child with a kidney transplantation and a 39-year-old patient with aplastic anemia), markers of recent B19V infection were still detectable in follow-up samples. For four B19V DNA positive samples, short sequences could be obtained, which clustered with genotype 1a reference strains. Our findings suggest that all cases of hematological disorders should be examined for specific B19V antibodies and DNA for accurate diagnosis and appropriate patient management.

Q fever in Bulgaria: Laboratory and epidemiological findings on human cases and outbreaks, 2011 to 2017.

BackgroundQ fever is a zoonosis, included in category B of particularly dangerous infectious agents and as such merits careful surveillance and regular updating of the information about its distribution.AimThis observational retrospective study aimed to provide an overview of Q fever incidence in Bulgaria in the period 2011 to 2017.MethodsAggregated surveillance data from Bulgaria's mandatory surveillance system, laboratory data on individual samples received at the National Reference Laboratory Rickettsiae and Cell Cultures and outbreak reports sent by the regional health authorities to the National Centre of Infectious and Parasitic Diseases, were used in this analysis. Cases were described by year, region, age group and most commonly identified risk behaviours.ResultsA total of 139 confirmed cases were reported in the study period (average annual incidence: 0.27 cases/100,000 inhabitants). No seasonality or trend in reported cases was observed. Cases were mostly sporadic, with two small outbreaks in 2017. Identified risk behaviours among cases were occupational exposure and consumption of milk and dairy products, although exposure data were incomplete. The male/female ratio was 1.4. The identification and resolution of the two rural outbreaks in 2017 with a total of 18 cases involved good practices: active case finding and collaboration between public health and veterinary authorities.ConclusionBetween 2011 and 2017, Bulgaria retained low Q fever incidence, mostly sporadic cases and two small outbreaks. Occupational exposure and consumption of milk and dairy products were the most often reported likely exposures among cases. The outbreak investigations demonstrate the application of good control practices.

Combined Laboratory Approach to Detection of Parvovirus B19 and Coxiella Burnetii in Patients with Fever of Unknown Origin.

BACKGROUND: Fever of unknown origin (FUO) is one of the greatest challenges for clinicians and patients. There are more than 200 etiological agents of FUO, among these the most common is the role of infection, neoplasms, and diseases of connective tissue. The aim of the present study is to investigate the role of the infectious agents parvovirus B19 (B19V) and Coxiella burnetii (C. burnetii) in the development of fever of unknown origin by a set of immunoenzymatic and molecular methods. METHODS: The present study included a total of 70 adult patients diagnosed with FUO and hospitalized in Bulgarian Hospitals. A control group of 26 healthy people were also included. Serological (indirect enzyme immunoassay test for detection of B19V and C. burnetii Ph. II specific IgM/IgG) and molecular (extraction and detection of infectious nucleic acids) methods were used. RESULTS: From all patients with FUO, a positive result for B19V-IgM was obtained in 18/70 (25.71%, 95% CI: 15.47 - 35.95) and the highest percentage was found in age groups 0 - 9 and 10 - 19 years. Protective B19V immunity and past viral infection was reported in 41/70 (58.57%, 95% CI: 47.03 - 70.11), and this percentage corresponded with the control group 16/26 (61.54%, 95% CI: 42.84 - 80.24). Anti-C. burnetii Ph. II-IgM was demonstrated in 13/70 (18.57%, 95% CI: 9.46 - 27.68). A relatively high percentage of affected patients were ≤ 40 years. Anti-C. burnetii Ph. II-IgG was detected in 24/70 (34.29%, 95% CI: 23.17 - 45.41). The control group has a 100% negative result for acute B19V and C. burnetii infection. A positive B19V-DNA result was obtained in 12/70 (17.14%, 95% CI: 8.31 - 25.97) patients. In 11/12 (91.67%) it was in combination with positive B19V-IgM marker. Of the total 70 sera tested, a positive PCR results for C. burnetii-DNA were obtained in 11 (15.71%, 95% CI: 7.18 - 24.24). According to clinical manifestation and concomitant symptoms, a high percentage of B19V and C. burnetii positives were associated with FUO and fever, headache, chills, and rash. CONCLUSIONS: It is of particular importance for a correct diagnosis of FUO to use a combined laboratory approach to prove acute or persistent infection and to test for a set of etiological agents.

Preliminary findings indicate nosocomial transmission and Roma population as most affected group in ongoing measles B3 genotype outbreak in Bulgaria, March to August 2017.

From March to August 2017, 165 measles cases were reported from three regions in Bulgaria. The age range was 0-55 years and 66% of the cases were under 9 years. The Roma population was disproportionally affected (89% of cases), 41% cases were unvaccinated and in 24 cases there was nosocomial transmission mostly in paediatric departments. A child under 12 months of age died. Control measures have been taken and the investigation is still ongoing.