Nasal carriage of various staphylococcal species in small ruminant lentivirus-infected asymptomatic goats.

The study was carried out in Polish goat population to estimate the prevalence of the nasal cavity infection with various staphylococcal species including methicillin-resistant Staphylococcus aureus(MRSA), investigate the potential permissive role of small ruminant lentivirus (SRLV) infection and determine the level of clonality of S. aureus nasal isolates. Nasal swabs and blood samples were collec-ted from 1300 clinically healthy adult goats from 21 Polish goat herds. Blood samples were serological-ly screened for SRLV. Staphylococci were isolated from nasal swabs and identified using classical microbiological methods, MALDI-TOF, multiplex-PCR, and their clonality was assessed using PFGE. Antimicrobial resistance was determined on the basis of minimum inhibitory concentration and by demonstration of the presence of the mecA gene encoding the multiplex-PCR PBP2a protein and of the five main types of staphylococcal cassette chromosome mec. The apparent prevalence of staphylococ-cal and S. aureus infection of the nasal cavity was 29.1% (CI 95%: 26.9%, 31.5%) and 7.3% (CI 95%: 6.1%, 8.8%), respectively. No relationship was found between the SRLV-infection and the presence of any staphylococcal species including S. aureus (p=0.143). Only 9.8% of S. aureus isolates were resistant to amoxicillin/clavulanic acid and 5.9% to chloramphenicol and ciprofloxacin. All tested isolates proved to be phenotypically and genotypically sensitive to methicillin, which yielded the appar-ent prevalence of MRSA of 0% (CI 95%: 0%, 7.0%). S. aureus isolates show high genetic similarity within goat herds, however vary considerably between herds. Goats do not appear to be an important source of S. aureus for humans in Poland.

Sequence variation in virulence-related genes of Bordetella pertussis isolates from Poland in the period 1959-2013.

This study aimed to characterise Bordetella pertussis isolates circulating in Poland since 1959. Sequence analysis of ptxA, ptxC, prn, tcfA, fim2, fim3 and ptxP for 175 clinical isolates and currently and previously used vaccine strains was performed. Clinical isolates from the period 1995-2013 were found to be different to three currently used vaccine strains harbouring the allelic combination ptxA2-ptxC1-ptxP1-prn1-tcfA2-fim2-1-fim3-1, seen frequently in Poland in the early pertussis vaccination period but not found after 1995. Generally, among B. pertussis isolates from the period 2000-2013, two genotypes predominated, ptxA1-ptxC1-ptxP1-prn1-tcfA2-fim2-2-fim3-1 and ptxA1-ptxC1-ptxP1-prn2-tcfA2-fim2-1-fim3-1, with frequencies of 45% and 32.5%, respectively. The isolates harbouring ptxA1-ptxC2-ptxP3-prn2-tcfA2-fim2-1-fim3-2 and ptxA1-ptxC2-ptxP3-prn2-tcfA2-fim2-1-fim3-1 profiles, currently highly prevalent within other European Union (EU) countries, were rarely found in Poland, as they circulated in the period 2000-2013 with frequencies of 10% and 5%, respectively. We hypothesise that several previous changes of strain composition in whole-cell pertussis vaccine produced locally and used since 1960 in Poland resulted in a more diverse immune pressure in the population, resulting in different prevalence of alleles compared to elsewhere.

Analysis of Bordetella pertussis clinical isolates circulating in European countries during the period 1998-2012.

Despite more than 50 years of vaccination, pertussis is still an endemic disease, with regular epidemic outbreaks. With the exception of Poland, European countries have replaced whole-cell vaccines (WCVs) by acellular vaccines (ACVs) in the 1990s. Worldwide, antigenic divergence in vaccine antigens has been found between vaccine strains and circulating strains. In this work, 466 Bordetella pertussis isolates collected in the period 1998-2012 from 13 European countries were characterised by multi-locus antigen sequence typing (MAST) of the pertussis toxin promoter (ptxP) and of the genes coding for proteins used in the ACVs: pertussis toxin (Ptx), pertactin (Prn), type 2 fimbriae (Fim2) and type 3 fimbriae (Fim3). Isolates were further characterised by fimbrial serotyping, multi-locus variable-number tandem repeat analysis (MLVA) and pulsed-field gel electrophoresis (PFGE). The results showed a very similar B. pertussis population for 12 countries using ACVs, while Poland, which uses a WCV, was quite distinct, suggesting that ACVs and WCVs select for different B. pertussis populations. This study forms a baseline for future studies on the effect of vaccination programmes on B. pertussis populations.

Lactobacillus rhamnosus GG suspected infection in a newborn with intrauterine growth restriction.

A disseminated Lactobacillus rhamnosus GG ATCC 53103 infection was suspected in a 6 day-old newborn with intrauterine growth restriction (IUGR) symptoms, treated empirically with antibiotics and given L. rhamnosus GG with the aim of preventing antibiotic-associated gastrointestinal complications. The level of C-reactive protein on day 5 compared with day 2 was increased in spite of negative urine and cerebrospinal fluid cultures. The blood sampled on day 6 was found to be positive for lactobacilli, and the isolate was pre-identified as L. rhamnosus or Lactobacillus casei on day 11. The strain identity was then verified as L. rhamnosus GG through PCR and 16S rRNA sequencing. Genotyping with the rep-PCR and AFLP methods confirmed the 100% genetic similarity for both the strain isolated from patient blood and the probiotic product. The newborn became touch-sensitive, cried a lot, had worsening laboratory test results, and increased inflammation parameters, but no fever was observed. After a further 9 days of antibiotic therapy, blood cultures became negative, and laboratory tests improved on day 25. The patient was discharged from the hospital after 27 days. IUGR with a possible link to L. rhamnosus GG bacteraemia might be a new potential risk group, beside patients with organ failure, immunocompromised status and dysfunctional gut barrier mechanisms, for which safe use of probiotics needs careful attention. Universally accepted or improved guidelines for the safer administration of probiotics in risk groups are urgently needed. This report should not discourage the use of probiotics, but should highlight the need for their careful use in IUGR patients.

PFGE and AFLP genotyping of Staphylococcus aureus subsp. anaerobius isolated from goats with Morel's disease.

Staphylococcus aureus subsp. anaerobius is the etiological agent of the Morel's disease in sheep and goats. The disease presents with subcutaneous abscesses, located mainly in the superficial lymph nodes. Forty-one isolates of S. aureus subsp. anaerobius were collected from two outbreaks of the Morel's disease in Poland in years 2006-2008. Analysis of DNA SmaI digests by PFGE showed that 35 of 41 isolates belonged to the same PFGE type, identical to the type strain of S. aureus subsp. anaerobius ATCC 35844, confirming high level of clonality of the species. The DNA patterns of the remaining identical 6 isolates, different from the reference strain only by two bands, were found closely related. Genotyping performed with AFLP technique revealed two clonal groups including 16 and 25 isolates, respectively. The study indicated that AFLP technique might be a better discriminatory tool for genetic analysis of S. aureus subsp. anaerobius isolates, when compared to PFGE.