Asymptomatic Leishmania infantum infections in humans living in endemic and non-endemic areas of Croatia, 2007 to 2009.

The prevalence of asymptomatic leishmaniasis in the general population of Croatia has not been studied to date. To assess the prevalence of Leishmania infantum specific IgG antibodies among immunocompetent residents of Croatia, sera from 2,035 persons (eastern coast of Adriatic Sea, n=1,186; Adriatic islands, n=653; mainland, n=196), were tested by an enzyme immunoassay. A total of 231 (11.4%) persons had anti-Leishmania antibodies. Multivariate analysis revealed that seropositivity was associated with geographic location and age. Residents of coastal areas and islands were significantly more seropositive than mainland residents (odds ratios (OR) 20.37 to 28.51). Moderate to high anti-Leishmania seroprevalence was found throughout the eastern Adriatic coast and islands (4.0% to 22.2%) including the sites previously considered non-endemic. A highly endemic focus was identified in central coastal Dalmatia (seroprevalence 22.2%; OR: 1.72; 95% confidence interval (CI): 1.33-2.22). Regarding age, children aged 0-9 years were the most vulnerable group for asymptomatic Leishmania infection (OR: 2.19; 95% CI: 1.16-4.14).

Prevalence of Toscana virus antibodies in residents of Croatia.

To assess the prevalence of Toscana virus (TOSV) infection among healthy residents of Croatia we tested sera from 2016 persons, for IgG antibodies to TOSV, by an enzyme immunoassay. A total of 755 (37.5%) persons had IgG antibodies to TOSV: 53.9%, 33.6% and 6.1% among residents of the islands, coastal area and mainland of Croatia, respectively. Risk factors significantly associated with seropositivity to TOSV were: living on islands (OR, 11.10; 95% CI, 6.02-20.50; p <0.001) or in coastal areas (OR, 6.96; 95% CI, 3.81-12.71; p <0.001) and increase of age (OR, 1.03; 95% CI, 1.02-1.03; p <0.001).

Antimicrobial susceptibility and beta-lactamase production of selected gram-negative bacilli from two Croatian hospitals: MYSTIC study results.

The meropenem yearly Susceptibility Test Information Collection (MYSTIC) programme is a global, longitudinal resistance surveillance network that monitors the activity of meropenem and compares its activity with other broadspectrum antimicrobial agents. We now report the antimicrobial efficacy of meropenem compared to other broad-spectrum agents within the selective Gram-negative pathogen groups from two Croatian Hospitals investigated between 2002-2007. A total of 1510 Gram-negative pathogens were tested and the minimum-inhibitory concentrations (MICs) were determined by broth microdilution method according to CLSI.There was no resistance to either imipenem or meropenem observed for Escherichia coli, Klebsiella pneumoniae and Proteus mirabilis in both medical centers. High resistance rates of K. pneumoniae to ceftazidime (18%), cefepime (17%) and gentamicin (39%) are raising concern. Acinetobacter baumannii turned out to be the most resistant Gram-negative bacteria with 81% resistant to ceftazidime, 73% to cefepime, 69% to gentamicin and 71% to ciprofloxacin. Almost 20% of Pseudomonas aeruginosa strains were resistant to imipenem, 13% to meropenem, 69% to gentamicin and 38% to ciprofloxacin.The prevalence of extended-spectrum beta-lactamases (ESBLs) in E. coli was 10% and in K. pneumoniae 49%. PCR and sequencing of the amplicons revealed the presence of SHV-5 in nine E. coli strains and additional tem-1 beta-lactamase five strains. Five K. pneumoniae strains were positive for bla(SHV-5 )gene. Eight ESBL positive Enterobacter spp. strains were found to produce tem and CtX-m beta-lactamases. Plasmid-mediated AmpC beta-lactamases were not found among K. pneumoniae, E. coli and Enterobacter spp. Three A. baumannii strains from Zagreb University Center were identified by multiplex PCR as OXA-58 like producers. Six A. baumannii strains from Split University Center were found to possess an ISAba1 insertion sequence upstream of bla(OXA-51 )gene. According to our results meropenem remains an appropriate antibiotic for the treatment of severe infections caused by Gram-negative bacteria. These data indicate that despite continued use of meropenem, carbapenem resistance is not increasing among species tested, except for A. Baumannii, in the two study hospitals and suggest that clinicians can still administer carbapenems as a reliable and effective choice in managing serious nosocomial infections.

Epidemiological features of Mediterranean spotted fever, murine typhus, and Q fever in Split-Dalmatia County (Croatia), 1982-2002.

We determined the epidemiological features of three zoonoses in hospitalized patients in southern Croatia. Patients were diagnosed by serological testing. Clinical and epidemiological data were also collected. Between 1982 and 2002, Mediterranean spotted fever (MSF) was diagnosed in 126 (incidence rate 1.27/100,000 per year), murine typhus (MT), in 57 (incidence rate 0.57/100,000 per year), and Q fever in 170 (incidence rate 1.7/100,000 per year) patients. MSF and Q fever were characterized by a marked seasonality. Incidences of Q fever and of MSF were higher for males than for females (P<0.0001 and P=0.0024, respectively). The most frequent of the three zoonoses in children was MSF. Q fever and MT cases were mostly seen in the 21-50 years age group. We found no statistically significant differences between season- and gender-specific incidence rates of MT. Whereas infections due to rickettsiae decreased, the incidence of Q fever increased over the last 12 years of the study.

[Monitoring bacterial resistance to antibiotics in the CroatianRepublic]. / Pracenje rezistencije bakterija na antibiotike u Republici Hrvatskoj.

In 1996 a Committee for antibiotic resistance surveillance in Croatia was founded by the Croatian Academy of Medical Sciences. In this study antibiotic surveillance results for the period June 1-December 31, 1997 from 12 microbiology laboratories throughout Croatia are presented. Sensitivity to antibiotics was determined by disk diffusion method for the following bacteria: Streptococcus pneumoniae, Staphylococcus aureus, Enterococcus spp., Escherichia coli, Klebsiella spp. and Pseudomonas aeruginosa. In general, high proportion of resistant isolates was recorded throughout Croatia, although some regional variations were noticed. Mean resistance of pneumococci to penicillin was 38%, in S. aureus resistance to methicillin was 47%, and 3rd generation cephalosporin-resistance in E. coli was 6% and in Klebsiella spp. 21%. In P. aeruginosa resistance to gentamicin averaged 50%, to imipenem 13% and to ceftazidim 8%. Future aims of the Committee are to continue routine antibiotic resistance surveillance during certain periods every year, and to estimate clinical significance of resistant bacteria, detect mechanisms of resistance and improve the quality of laboratory work through education and quality control projects.

Antibiotic resistance among enterococcal strains isolated from clinical specimens.

The distribution and resistance patterns of clinical isolates of enterococci from hospital patients were compared with those obtained from outpatients. Of 235 enterococcal isolates 212 (90.2%) were identified as Enterococcus faecalis and 23 (9.8%) as E. faecium. E. faecium occurred more frequently in specimens from hospitalized patients than from outpatients (P < 0.001). Over 90% of all E. faecalis isolates were susceptible to ampicillin. Resistance to ampicillin occurred in 66.7% of hospital strains of E. faecium. High-level resistance to gentamicin (MIC > 500 mg/l) was seen in 37.03% of inpatients' and in 11.5% of outpatients' E. faecalis isolates and in 76.2% of hospital isolates of E. faecium. High-level streptomycin resistance (MIC > 2000 mg/l) occurred in 52.8% of E. faecalis and 76.2% of E. faecium hospital isolates. There were no isolates resistant to vancomycin. The community acquired strains isolated from outpatients were more susceptible than isolates from hospitalized patients to all antimicrobial agents tested.

Prevalence of antibodies to Toxoplasma gondii in the female population of the County of Split Dalmatia, Croatia.

The prevalence of IgG antibodies reactive with Toxoplasma gondii in the female population of the County of Split Dalmatia was investigated by enzyme linked immunosorbent assay. Of a total of 1109 serum samples collected from female subjects, 423 (38.1%) reacted with T. gondii. The frequency of positive sera increased with age. Theoretical incidence of congenital toxoplasmosis was calculated from the annual increase in cumulative prevalence of antibodies between different age groups among the women of childbearing age. The estimated theoretical incidence of congenital toxoplasmosis was 1.4 per 100 pregnancies of adolescents (16-20 years) and decreased to 0.1% in seronegative pregnant women aged 41-45.

[Rickettsiales--modern findings]. / Rickettsiales--suvremene spoznaje.

The term rickettsiae has as a rule encompassed the intracellular bacteria. Molecular studies brought new data to rickettsial taxonomy. Many new data on rickettsia have been accumulated over recent years, and a comparison of the newly discovered diseases with previously known rickettsioses, as well as with their agents is of interest. The number of "new" agents that have been discovered in the last few years is remarkable. This review discusses the current knowledge of bacterial species that historically belonged to the order Rickettsiales, as well as the role of these agents as human and animal pathogens.

Synergistic anti-varicella-zoster virus activity of interferon-alpha 2a and acyclovir in corneal cells.

Human corneal stromal (HCS) cells in cultures established from donor corneas can serve as host cells for replication of varicella-zoster virus (VZV). Comparative infectious centers assays suggest that HCS cells are more restrictive hosts than MRC-5 cells, a line of human embryonic lung fibroblasts, commonly used for VZV isolation. VZV propagated in MRC-5 cells was infectious for both MRC-5 and HCS cells, but titers in HCS were one fifth of those in MRC-5 cells. Inhibition of VZV replication in HCS cells by acyclovir (ACV), recombinant human interferon-alpha 2a (IFN-alpha 2a), or the combination of these two antivirals was detected by both an infectious centers-plaque-reduction assay and an ELISA method using monoclonal anti-VZV antibody. In the infectious centers-plaque-reduction assay combinations of ACV with IFN-alpha 2a showed synergistic anti-VZV activity. VZV protein synthesis, as detected by the ELISA, was a less sensitive measure of the antiviral effects producing an ED50 value of 50 microM for ACV, five to ten times the ED50 determined in the plaque reduction assay. In the ELISA, high titers of IFN-alpha 2a (2000 IU/ml) decreased virus antigen expression only slightly, while combinations of ACV and IFN-alpha 2a were synergistic in their detected anti-VZV activity. These data document the replication of VZV in HCS cells and demonstrate that VZV is sensitive to the synergistic antiviral action of combinations of IFN-alpha 2a and ACV.

Two outbreaks of typhoid fever related to the war in Bosnia and Herzegovina.

Two outbreaks of typhoid fever caused by Salmonella typhi of the same phagotype (A, biotype II), and antibiotic susceptibility are reported. Both occurred during the war in Bosnia and Herzegovina. The first outbreak appeared among the refugees from the town of Jajce. The second outbreak appeared among the inhabitants in the village of Vidosi near Livno. This report describes main clinical, epidemiological and laboratory findings for 22 patients treated in Split University Hospital, Croatia, in the period November 1992-January 1993. Possible epidemiological connections between those two outbreaks are discussed.

Prevalence of antibodies to rickettsiae in the north-western part of Bosnia and Herzegovina.

The prevalence of rickettsial antibodies in north-western part of Bosnia and Herzegovina was studied. Among 231 sera tested by complement fixation (CF) positive were: 61.5% for Rickettsia typhi, 4.3% for R. prowazekii, 1.7% for R. conorii and 19.0% for Coxiella burnetii. Of 183 sera tested by indirect immunofluorescence assay (IFA) 37.7% reacted with R. typhi, 1.6% with R. conorii and 22.4% with C. burnetii. The results show that at least R. typhi and C. burnetii are highly endemic in this area.