Knowledge and attitudes of pregnant women on maternal immunization against COVID-19 in Croatia.

OBJECTIVES: The aim of this study was to assess pregnant women's knowledge and attitudes regarding maternal COVID-19 immunization during pregnancy. METHODS: A cross-sectional study was performed in two teaching hospitals between May and October 2021 in Zagreb, Croatia. During antenatal clinic visit pregnant women were approached and asked to fill out a predesigned questionnaire about their knowledge and attitudes towards COVID-19 vaccination. Collected data was later analyzed. RESULTS: A total of 430 women participated in the study. Only 16% of women expressed their willingness to be vaccinated against COVID-19 if offered, despite that 71% of them believe that COVID-19 might be a serious illness in pregnant women. The most important obstacle in having better acceptance of the vaccines is in the assumption that the vaccines are not safe for pregnant women (73%) or the fetus (75%), or that the vaccines are not effective (41%). The relationship exists between acceptance of vaccination in general and willingness to get other vaccines in pregnancy and readiness to be vaccinated against COVID-19 in pregnancy. Only one out of 55 women who were not adherent to the current vaccination recommendations in Croatia would accept the COVID-19 vaccine during pregnancy if offered. 21 (5%) women stated that vaccination against influenza and pertussis during pregnancy is necessary and 13 (62%) of them would get vaccinated against COVID-19 if offered. CONCLUSIONS: This study showed that the crucial reasons for refusing vaccination against COVID-19 among pregnant women in Croatia are the concerns about the vaccines' effectiveness and safety. All healthcare providers should put more effort into education of pregnant women on risks of COVID-19, as well as on the benefits and safety of the vaccines.

Parents' attitudes toward childhood COVID-19 immunization in Croatia: a multicenter cross-sectional study.

AIM: To assess parents' attitudes toward childhood COVID-19 immunization in Croatia. METHODS: In this multicenter cross-sectional study, we collected data from four tertiary care facilities in Zagreb, Split, and Osijek between December 2021 and February 2022. During the visit to the Pediatric Emergency Departments, parents were asked to fill out a highly-structured questionnaire about their attitudes toward COVID-19 immunization in children. RESULTS: The sample consisted of 872 respondents. A total of 46.3% of respondents were hesitant about vaccinating their child against COVID-19, 35.2% definitely did not intend to vaccinate their child, and 18.5% definitely intended to vaccinate their child. Parents who were themselves vaccinated against COVID-19 were more likely than unvaccinated parents (29.2% and 3.2%, P<0.001) to vaccinate their children. Parents agreeing with the epidemiological guidelines were more inclined to vaccinate their children, as were parents of older children and parents of children vaccinated according to the national program schedule. Child comorbidities and respondents' history of COVID-19 were not associated with childhood vaccination intention. Ordinal logistic regression revealed that the most important predictors for a positive parents' attitude toward vaccinating their child were parents' vaccination status and regular vaccination of their child according to the national immunization program schedule. CONCLUSION: Our results demonstrate Croatian parents' mostly hesitant and negative attitudes toward childhood COVID-19 immunization. Future vaccination campaigns should target unvaccinated parents, parents with younger children, and parents of children with chronic diseases.

Campylobacter jejuni subdural hygroma infection in a 2-year old boy: case report and a brief literature review.

BACKGROUND: Campylobacter jejuni is a common cause of acute gastroenteritis, but central nervous system infections are rare manifestations of Campylobacter infection. Therefore, C. jejuni trauma-related subdural hygroma infection in children is poorly described in the literature. CASE PRESENTATION: We described a 2-year old boy with lobar holoprosencephaly presenting with subdural hygroma following head trauma. C. jejuni infection was confirmed from a subdural hygroma sample by culture as well as by DNA sequencing of a broad range 16S rDNA PCR product. Cerebrospinal fluid from the ventriculoperitoneal shunt remained sterile. Combined neurosurgical and antimicrobial treatment led to complete recovery. Review of the literature showed that the most common manifestation of Campylobacter central nervous system infection is meningitis, mostly in neonates, and subdural hygroma infection was described for only one case. CONCLUSIONS: Subdural hygroma infection caused by C. jejuni is a rare clinical condition in children. Molecular methods represent an important tool for the detection of rare or unexpected pathogens. No standard recommendations for antimicrobial treatment of C. jejuni subdural space infection in children are available, but meropenem treatment combined with surgery seems to be an effective approach.

Pediatric tertiary emergency care departments in Zagreb, Rijeka, and Split before and during the coronavirus disease 2019 pandemic: a Croatian national multicenter study.

AIM: To assess the number of visits to pediatric emergency departments in Croatia and reasons for visiting before and during the coronavirus disease 2019 (COVID-19) pandemic. METHODS: We reviewed the medical records of pediatric patients visiting emergency departments of four tertiary medical centers between February 25 and April 25, 2018 and 2019, and between February 25 and April 24, 2020. Antimicrobial prescription was analyzed as well. RESULTS: There were altogether 46 544 visits - 18218 in 2018, 19699 in 2019, and 8634 in 2020. The overall number of visits in 2020 significantly decreased compared with 2018 and 2019 (52% and 56% reduction, respectively), mostly due to a decreased number of visits due to certain infectious diseases: acute gastroenteritis (89.2%), sepsis/bacteremia (81.2%), urinary tract infections (55.3%), and lower respiratory tract infections (58%). Most visits were self-referrals regardless of the analyzed period, and the majority of patients did not require hospitalization. There were no significant differences in the number of visits requiring urgent medical care, such as those due to seizures and urgent surgery. The most frequently prescribed antibiotic in all periods was amoxicillin, followed by amoxicillin/clavulanate and oral cephalosporins. CONCLUSION: A significant reduction in the number of pediatric emergency department visits and hospital admissions is indirectly related to the COVID-19 pandemic. Most of the reduction was due to a decreased number of infectious disease cases. However, the number of visits requiring urgent medical intervention did not change.

Epidemiological and clinical features of Croatian children and adolescents with a PCR-confirmed coronavirus disease 2019: differences between the first and second epidemic wave.

AIM: To describe epidemiological and clinical features of Croatian children and adolescents with a polymerase chain reaction (PCR)-confirmed coronavirus disease 2019. METHODS: Data on patients aged ≤19 years with a positive SARS-CoV-2 PCR test recorded in the period March 12-May 12 (first wave) and June 19-July 19, 2020 (second wave) were retrospectively analyzed. The periods were separated by several weeks with no incident cases. RESULTS: We analyzed data on 289 children and adolescents (6.5% of all cases; incidence rate [IR]=3.54, 95% confidence interval [CI] 3.14-3.97/million person-days), 124 in the first wave (IR=2.27) and 165 in the second wave (IR=6.37): IRR second/first=2.71 (2.13-3.44). During the first wave, the incidence was highest in infants (IR=3.48), while during the second wave it progressively increased to IR = 7.37 in 15-19-year olds. Family members were the key epidemiological contacts (72.6% cases), particularly during the first wave (95.8% vs 56.3%). Overall, 41.3% patients were asymptomatic, 25.3% in the first and 52.6% in the second wave. Age 15-19 years (vs younger) was associated with a higher (RR = 1.26, 1.02-1.54) and infection in the second wave with a lower probability (RR=0.66, 0.53-0.81) of being symptomatic. The most common symptoms were fever, cough, and rhinorrhea. In children aged ≥7 years, headache, anosmia/ageusia, and sore throat were also recorded. Only one child suffered a severe disease. All but 18 (7.8%) children were treated only symptomatically, and all fully recovered. CONCLUSION: A large proportion of SARS-CoV-2 PCR-positive children/adolescents were asymptomatic. The associated disease was predominantly mild, comparably so in the first and second pandemic wave.

High Detection Rates of Human Bocavirus in Infants and Small Children with Lower Respiratory Tract Infection from Croatia.

BACKGROUND: Human bocavirus (HBoV) is known to cause lower respiratory tract infections (LRTI) in children and may result in substantial morbidity and mortality. The aim of this study was to determine HBoV prevalence among hospitalized infants and small children with acute LRTI in Zagreb, Croatia, as well as to evaluate HBoV DNA quantity in samples in relation to the patients' age and co-infection with other respiratory viruses. METHODS: During winter season 2016/2017, a total of 295 children younger than three years of age who were admitted to hospitals with LRTI were tested for the presence of HBoV, respiratory syncytial virus (RSV), adenovirus (ADV), parainfluenza virus (PIV) types 1 to 3, and human metapneumovirus (HMPV). HBoV was detected with a real-time PCR method, and the other viruses were diagnosed using monoclonal antibodies in direct fluorescence assay. RESULTS: Viral etiology was proven in 225/295 (76.3%) of patients. The most commonly diagnosed virus was RSV (59.3%), followed by HBoV (23.1%), PIVs (4.4%), ADV (3.1%), and HMPV (1.4%). HBoV-infected children were older than RSV-infected children; likewise, detection rates of HBoV infection increased with age, while RSV infection rates decreased with age. In 51% of HBoV-positive samples an additional respiratory virus was also detected. There was no difference in HBoV DNA quantity between samples with single virus detection and those with multiple virus detection (p = 0.056), although samples positive only for HBoV showed higher cycle threshold values. There was no difference in HBoV DNA quantity in samples of different age groups (p > 0.05). CONCLUSIONS: Frequent detection of HBoV in small children with LRTI, even in combination with other viruses, highlights its role in the pathogenesis of respiratory disease.

Chemokines CXCL10, CXCL11, and CXCL13 in acute disseminated encephalomyelitis, non-polio enterovirus aseptic meningitis, and neuroborreliosis: CXCL10 as initial discriminator in diagnostic algorithm?

We investigated potential diagnostic usefulness of serum and cerebrospinal fluid (CSF) concentrations of chemokines CXCL10, CXCL11, and CXCL13 in pediatric patients with acute disseminated encephalomyelitis (ADEM) (n = 23), non-polio enterovirus aseptic meningitis (NPEV AM) (n = 20), and neuroborreliosis (NB) (n = 21) and children with acute infectious diseases with neurological symptoms but with excluded neuroinfection/neuroinflammation (controls, n = 20). CSF levels of CXCL10 and CXCL11 were higher in patients with NPEV AM than those in other children, and CXCL10 levels showed a high discriminative potential (area under the receiver operating characteristic curve, ROC, 0.982) with high specificity and sensitivity (both 95%). CSF levels of CXCL13 were higher in NB patients than those in other children; however, discriminative potential (area under ROC curve 0.814) and diagnostic properties were moderate (sensitivity 67%, specificity 97%). Data suggest usefulness of chemokine quantification as a diagnostic aid in children with suspected ADEM, NPEV AM, or NB.

Common position of indels that cause deviations from canonical genome organization in different measles virus strains.

BACKGROUND: The canonical genome organization of measles virus (MV) is characterized by total size of 15 894 nucleotides (nts) and defined length of every genomic region, both coding and non-coding. Only rarely have reports of strains possessing non-canonical genomic properties (possessing indels, with or without the change of total genome length) been published. The observed mutations are mutually compensatory in a sense that the total genome length remains polyhexameric. Although programmed and highly precise pseudo-templated nucleotide additions during transcription are inherent to polymerases of all viruses belonging to family Paramyxoviridae, a similar mechanism that would serve to non-randomly correct genome length, if an indel has occurred during replication, has so far not been described in the context of a complete virus genome. METHODS: We compiled all complete MV genomic sequences (64 in total) available in open access sequence databases. Multiple sequence comparisons and phylogenetic analyses were performed with the aim of exploring whether non-recombinant and non-evolutionary linked measles strains that show deviations from canonical genome organization possess a common genetic characteristic. RESULTS: In 11 MV sequences we detected deviations from canonical genome organization due to short indels located within homopolymeric stretches or next to them. In nine out of 11 identified non-canonical MV sequences, a common feature was observed: one mutation, either an insertion or a deletion, was located in a 28 nts long region in F gene 5' untranslated region (positions 5051-5078 in genomic cDNA of canonical strains). This segment is composed of five tandemly linked homopolymeric stretches, its consensus sequence is G6-7C7-8A6-7G1-3C5-6. Although none of the mononucleotide repeats within this segment has fixed length, the total number of nts in canonical strains is always 28. These nine non-canonical strains, as well as the tenth (not mutated in 5051-5078 segment), can be grouped in three clusters, based on their passage histories/epidemiological data/genetic similarities. There are no indications that the 3 clusters are evolutionary linked, other than the fact that they all belong to clade D. CONCLUSIONS: A common narrow genomic region was found to be mutated in different, non-related, wild type strains suggesting that this region might have a function in non-random genome length corrections occurring during MV replication.

Early Evolution of Human Respiratory Syncytial Virus ON1 Strains: Analysis of the Diversity in the C-Terminal Hypervariable Region of Glycoprotein Gene within the First 3.5 Years since Their Detection.

OBJECTIVE: Characterization of the phylogeny and diversity of human respiratory syncytial virus (HRSV) genotype ON1 that occurred during its early evolution (within the first 3.5 years since the detection of the first ON1 strains). ON1 strains have a 72-nucleotide-long in-frame duplication within the second hypervariable domain of the glycoprotein gene (HVR2). METHODS: All available HVR2 sequences of strains belonging to the ON1 genotype published prior to June 20, 2014 were collected. Multiple sequence alignments, phylogeny, phylogeography, sequence clustering and putative protein analyses were performed. RESULTS: The worldwide spread and diversification of ON1 strains are presented. Only in a minority of ON1 strains do the two replicas remain identical, and various ON1 strains possess common differences between the first and the second copy (segments A and B). Mutations of the progenitor sequence were more frequent in segment B, a higher overall diversity on the protein level and more putative glycosylation sites exist in segment B, and, unlike in segment A, positive selection acts on that protein region. CONCLUSIONS: The fast spread of the novel HRSV genotype ON1 has been accompanied by its rapid concurrent diversification. Differences in variability of the two replicas within HVR2 were detected, with C-terminal replica being more variable.

Risk factors for coronary artery abnormalities in children with Kawasaki disease: a 10-year experience.

Kawasaki disease (KD) is an acute systemic vasculitis of childhood. Due to development of coronary artery aneurysms (CAA) it is considered the most common cause of acquired heart disease in children. The clinical and laboratory features of patients with complete and incomplete KD were compared in order to identify the possible predictors of CAA development. A cross-sectional study of children with KD treated at the University Hospital for Infectious Diseases, Zagreb, between January 2003 and December 2012 was conducted. A total of 111 KD patients were included; 70.3% patients had complete KD. Patients with complete KD had more frequently rash, changes on extremities and mucous membranes, as well as higher serum bilirubin, aminotransferases, gamma-glutamyl transferase and lactate dehydrogenase levels. Patients with incomplete KD had longer duration of fever before the diagnosis (8 vs. 7 days) and delayed IVIG treatment (day 8 vs. 7). CAA was detected in seven children (6.3%). Disease duration before hospitalization >6 days (OR 7.16, 95% CI 1.51-100.35), age <6 months (OR 25.86, 95% CI 1.68-398.35) and platelet count >771 after the 7th day of disease (OR 13.33, 95% CI 2.19-80.87) were independently associated with CAA development. The diagnosis and treatment in incomplete KD can be delayed due to the absence of major criteria. Age, duration of symptoms prior hospitalization and platelet count were identified as independent predictors of CAA development.

Epidemiologic and Clinical Characteristics and Risk Factors for Severe Community-Acquired Clostridium Difficile Infection in Children.

Although children most frequently suffer from milder forms of community-acquired Clostridium difficile infection, severe cases and fatal outcomes have been recorded. In this study we identified older children (>12 years of age) and patients who had surgery up to 6 months before Clostridium difficile infection onset as a subgroup at somewhat higher risk for severe community-acquired Clostridium difficile infection.

Invasive meningococcal disease in South-Eastern European countries: Do we need to revise vaccination strategies?

Invasive meningococcal disease (IMD) is an acute life-threatening infection caused by the gram-negative bacterium, Neisseria meningitidis. Globally, there are approximately half a million cases of IMD each year, with incidence varying across geographical regions. Vaccination has proven to be successful against IMD, as part of controlling outbreaks, and when incorporated into national immunization programs. The South-Eastern Europe Meningococcal Advocacy Group (including representatives from Croatia, the Czech Republic, Greece, Hungary, Poland, Romania, Serbia, Slovenia and Ukraine) was formed in order to discuss the potential challenges of IMD faced in the region. The incidence of IMD across Europe has been relatively low over the past decade; of the countries that came together for the South-Eastern Meningococcal Advocacy Group, the notification rates were lower than the European average for some country. The age distribution of IMD cases was highest in infants and children, and most countries also had a further peak in adolescents and young adults. Across the nine included countries between 2010 and 2020, the largest contributors to IMD were serogroups B and C; however, each individual country had distinct patterns for serogroup distribution. Along with the variations in epidemiology of IMD between the included countries, vaccination policies also differ.

Rotavirus vaccination in central Europe.

Each year, rotavirus (RV) infection is the leading cause of acute gastroenteritis requiring hospitalisation and of nosocomially transmitted diseases in children younger than 5 years across Central European Vaccination Awareness Group (CEVAG) countries; however, inadequate surveillance systems and lack of routine RV testing still exist in most CEVAG countries, making it difficult to accurately assess the present burden of acute RV gastroenteritis in the younger population. Furthermore, routine immunisation of infants with RV vaccines has not been implemented, and no official and uniform recommendations exist in most of the countries in these territories. The present study provides CEVAG country-specific estimates of the disease burden of RV gastroenteritis among the youngest population and presents evidence-based advice on the use of RV vaccines in the region, while providing a framework for vaccination at the national level.

Herpes simplex primo-infection in an immunocompetent host with eosinophilic esophagitis.

Eosinophilic esophagitis and herpes simplex esophagitis are separately well-described entities, but their simultaneous occurrence may pose a special challenge to the clinician, especially regarding the optimal therapeutic approach. The following case report describes a patient with a history of cow's milk and dairy products intolerance, but without an underlying immunologic defect, in whom eosinophilic esophagitis was diagnosed in the course of primary herpes simplex virus 1 (HSV1) infection that clinically presented as herpes labialis and severe esophagitis. The diagnosis was confirmed by a polymerase chain reaction from cytological brush and by immunohistochemical staining that detected the presence of HSV1 DNA in esophageal mucosa, and histologically by persistent eosinophil-predominant inflammation, typical of eosinophilic esophagitis. Despite severe clinical presentation, the HSV1 infection was self-limited. After a directed elimination diet was introduced, the clinical course was favorable, without the need for antiviral therapy.

Incidence and Clinical Phenotype of Multisystem Inflammatory Syndrome in Children After Two SARS-CoV-2 Pandemic Waves: A Croatian Prospective Nationwide Study.

This prospective nationwide study in Croatia (March 1, 2020-December 31, 2021) embraced 121 children with multisystem inflammatory syndrome. Incidence rates, disease course and outcomes were similar to those reported from other European countries. The severe acute respiratory syndrome coronavirus 2 virus Alpha strain appeared associated with a higher propensity to result in multisystem inflammatory syndrome in children than the Delta strain but did not appear related to disease severity.

Distribution of Epstein-Barr Virus LMP1 Variants in Patients with Infectious Mononucleosis and Association with Selected Biochemical and Hematological Parameters.

The molecular diversity of Epstein-Barr virus (EBV) is exceptionally complex and based on the characterization of sequences coding for several viral genes. The aim of this study was to analyze the distribution of EBV types 1 and 2 and to characterize LMP1 variants in a cohort of 73 patients with infectious mononucleosis (IM), as well as to investigate a possible association between viral diversity and relevant clinical parameters. Population-based sequencing of EBNA-2 gene showed the presence of EBV type 1 in all IM patients. Analysis of LMP1 gene found a restricted repertoire of LMP1 variants with the predominance of wild-type B95-8, China1, Mediterranean and North Carolina variants with the presence of more than one LMP1 variant in 16.4% of patients. Co-infections with different LMP1 variants were associated with significantly higher levels of C-reactive protein and lower levels of maximal neutrophil counts and minimal platelet count. The results of this study have shown a narrow repertoire of LMP1 variants and an exclusive presence of EBV type 1 in a cohort of IM from Croatia, suggesting a characteristic local molecular pattern of this virus. The clinical importance of distinct immunobiological features of IM patients with LMP1 variant co-infections needs to be investigated further.