Chlamydia trachomatis, Mycoplasma genitalium and Ureaplasma urealyticum among students in northern Norway.

BACKGROUND: The prevalence of Mycoplasma genitalium and Ureaplasma genitalium in populations outside sexually transmitted infection clinics in Norway is unknown. OBJECTIVE: To assess the prevalence of potential sexually transmitted organisms in a non-clinical setting, among college students in Northern Norway. METHODS: In total 655 students, 449 men and 206 women, were tested for Chlamydia trachomatis, M. genitalium, and U. urealyticum by nucleic acid amplification testing of urine samples. All subjects completed questionnaires. RESULTS: Among the included men, the prevalences of C. trachomatis, M. genitalium, and U. urealyticum were 4.2%, 1.1% and 8.9%, respectively. Prevalence among included women was 1.9%, 1% and 8.2%, respectively. In men, the number of sexual partners in the preceding 6 months was associated with prevalence of U. urealyticum and C. trachomatis. CONCLUSIONS: U. urealyticum appeared more prevalent than C. trachomatis and increased number of sexual partners was associated with increased risk of a positive test. M. genitalium had a low prevalence.

Chlamydia trachomatis, Mycoplasma genitalium and Ureaplasma urealyticum in clinical and non-clinical settings, Arkhangelsk Oblast, Russia.

Russia and Eastern Europe have the fastest growing HIV epidemic in the world. As sexually transmitted infections (STIs) play an important role in HIV transmission, we conducted this study to find the prevalence of three microorganisms associated with STIs in Arkhangelsk Oblast, Russia. First void urine from 1729 participants was analysed using nucleic acid amplification testing, and all participants completed a questionnaire. One hundred and twelve (6.5%) were tested positive for Chlamydia trachomatis, 67 (3.9%) for Mycoplasma genitalium and 221 (12.8%) for Ureaplasma urealyticum. A significant association was found between C. trachomatis and U. urealyticum (odds ratio [OR] 1.85; 95% confidence interval [CI] 1.1 to 3.0). U. urealyticum was associated with similar social demographics and sexual risks as C. trachomatis and M. genitalium. This suggests that U. urealyticum has a possible role as an STI pathogen or might be a contributing factor for the spread of other STIs.

Novel real-time PCr for detection of Schistosoma japonicum in stool.

Chemotherapy has been used on a large scale in countries where the blood fluke Schistosoma japonicum is endemic. This has led to a lower intensity of infections and consequently lower diagnostic values of commonly used diagnostic tests like serology and Kato-Katz stool smear. We designed a novel real-time PCR method for detection of S. japonicum in stool samples. Further, we evaluated different versions of an inexpensive, non-commercial extraction method, ROSE, as well as the commercial QIAamp DNA Stool Mini Kit. PCR primer sequences were designed targeting the mitochondrial NADH dehydrogenase I gene. Bovine serum albumin was added to the DNA extracts and SYBR Green was used for detection. The PCR method was evaluated with non-infected stool samples spiked with S. japonicum eggs. It demonstrated high sensitivity, even in samples containing a single egg. The two extraction methods were equally effective. The PCR was specific for S. japonicum when tested against other Schistosoma species, Trichuris trichiura, hookworm and Taenia sp. We conclude that this novel real-time PCR, in combination with either ROSE or QIAamp DNA Stool Mini Kit extraction, is a sensitive and specific tool for diagnosing S. japonicum in human stool samples.

Laboratory diagnosis of respiratory diseases: PCR versus serology.

We present a comparison between serology and genetic detection of three bacterial pathogens causing lower respiratory tract infection (LRI). We evaluated serology and PCR for the detection of Mycoplasma pneumoniae, Bordetella pertussis and Chlamydia pneumoniae from 1712 nasopharyngeal and serum samples. For 856 nasopharyngeal samples, average PCR time was 7.2 days, the parallel serum samples was 13 days. Automated extraction of nucleic acids reduces average PCR time to 6.7 days.

Field detection of Francisella tularensis.

A field investigation was undertaken following an outbreak of water-borne tularemia in Northern Norway. Francisella tularensis bacterial cellular components were analysed by rapid immunochromatography (RI)-testing, enzyme-linked immunosorbent assay (ELISA) and polymerase chain reaction (PCR). Water from 1 reservoir, fed from a rapid stream, tested negative. From another reservoir, 2 of a chain of 3 wells tested negative. The third well, at the end of the chain, contained lemming (Lemmus lemmus) carcasses and gave ample proof of F. tularensis contamination. We concluded that the origin of the outbreak was dead, infective lemming carcasses in the water sources. For the various sampling materials, the RI-test proved itself particularly handy and versatile, compared with the ELISA and the PCR.

Long PCRs of transposons in the structural analysis of genes encoding acquired glycopeptide resistance in enterococci.

Glycopeptide-resistant enterococci (GRE) associated with multiple antibiotic resistance present a major challenge to clinical practice and infection control due to limited or nonexistent antimicrobial treatment options. The genes encoding VanA- and VanB-type glycopeptide resistance have been shown to reside on transposons Tn1546 and Tn1547, respectively. These transferable genetic elements may carry the resistance determinants between and within different ecological niches. Molecular epidemiological studies of nosocomial outbreaks of VanA- and VanB-type GRE indicate horizontal transfer of glycopeptide resistance genes as an important mechanism for the spread of GRE. To target infection control and better understand the epidemiology of GRE, outbreak investigations and molecular epidemiological studies should therefore apply at least two different approaches, i.e., molecular-typing methods to analyze bacterial genomic heterogeneity and structural analysis of mobile resistance determinants. Here we describe the development and use of long PCRs in the structural analysis of vanA and vanB gene clusters in GRE.

Transmission of VanA-type vancomycin-resistant enterococci and vanA resistance elements between chicken and humans at avoparcin-exposed farms.

The genetical relatedness between epidemiologically linked fecal VRE strains from poultry farmers (n = 5) and their broilers (n = 7) at five avoparcin-exposed Norwegian farms was examined. Pulsed-field gel electrophoresis (PFGE) of bacterial chromosomal digests and structural analysis of vanA resistance elements was performed. Animal and human Enterococcus faecium strains at one farm were genetically closely related with indistinguishable vanA elements and a single band position difference in PFGE analysis. Examination of the vanA elements in genetically unrelated strains by restriction enzyme digestion of Tn1546 long-PCR amplicons and ORF2-vanR intergenic sequencing revealed a pool of at least two distinct vanA gene cluster groups in the two reservoirs. The results indicate that transmission of VanA glycopeptide resistance in enterococci between human and animal at avoparcin-exposed farms can occur by direct transfer of VRE strains as well as horizontal spread of resistance genes between strains.

Experimental expression in mice and spontaneous expression in human SLE of polyomavirus T-antigen. A molecular basis for induction of antibodies to DNA and eukaryotic transcription factors.

We have previously demonstrated that experimental expression of the polyomavirus transcription factor T-antigen has the potential to induce anti-DNA antibodies in mice. Two sets of independent evidences are presented here that demonstrate a biological relevance for this model. First, we describe results demonstrating that mice inoculated with T-antigen-expressing plasmids produced antibodies, not only to T-antigen and DNA, but also to the DNA-binding eukaryotic transcription factors TATA-binding protein (TBP), and to the cAMP-response-element-binding protein (CREB). Secondly, we investigated whether polyomavirus reactivation occurs in SLE patients, and whether antibodies to T-antigen, DNA, and to TBP and CREB are linked to such events. Both within and among these SLE patients, frequent polyomavirus reactivations were observed that could not be explained by certain rearrangements of the noncoding control regions, nor by corticosteroid treatment. Linked to these events, antibodies to T-antigen, DNA, TBP, and CREB were detected, identical to what we observed in mice. Antibodies recognizing double-stranded DNA were confined to patients with frequent polyomavirus reactivations. The results described here indicate that cognate interaction of B cells recognizing DNA or DNA-associated proteins and T cells recognizing T antigen had taken place as a consequence of complex formation between T ag and DNA in vivo in the context of polyomavirus reactivations.