Toxigenic Corynebacterium diphtheriae is an important and potentially fatal threat to patients and public health. During the current dramatic influx of refugees into Europe, our objective was to use whole genome sequencing for the characterization of a suspected outbreak of C. diphtheriae wound infections among refugees. After conventional culture, we identified C. diphtheriae using matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) and investigated toxigenicity by PCR. Whole genome sequencing was performed on a MiSeq Illumina with >70×coverage, 2×250 bp read length, and mapping against a reference genome. Twenty cases of cutaneous C. diphtheriae in refugees from East African countries and Syria identified between April and August 2015 were included. Patients presented with wound infections shortly after arrival in Switzerland and Germany. Toxin production was detected in 9/20 (45%) isolates. Whole genome sequencing-based typing revealed relatedness between isolates using neighbour-joining algorithms. We detected three separate clusters among epidemiologically related refugees. Although the isolates within a cluster showed strong relatedness, isolates differed by >50 nucleotide polymorphisms. Toxigenic C. diphtheriae associated wound infections are currently observed more frequently in Europe, due to refugees travelling under poor hygienic conditions. Close genetic relatedness of C. diphtheriae isolates from 20 refugees with wound infections indicates likely transmission between patients. However, the diversity within each cluster and phylogenetic time-tree analysis suggest that transmissions happened several months ago, most likely outside Europe. Whole genome sequencing offers the potential to describe outbreaks at very high resolution and is a helpful tool in infection tracking and identification of transmission routes.

We report an imported case of louse-borne relapsing fever in a young adult Eritrean refugee who presented with fever shortly after arriving in Switzerland. Analysis of blood smears revealed spirochetes identified as Borrelia recurrentis by 16S rRNA gene sequencing. We believe that louse-borne relapsing fever may be seen more frequently in Europe as a consequence of a recent increase in refugees from East Africa travelling to Europe under poor hygienic conditions in confined spaces.

The induction of antibodies against peptides requires the presence of a T helper cell epitope. In the absence of an added T-cell epitope only 10% of the mice, or less depending on the strain, gave an antibody response to a series of peptides of the measles virus (MV) fusion (F) protein. After coimmunization with a non-covalently coupled T-cell epitope more than 60% of the peptides became immunogenic. Considerable differences became apparent when BALB/c mice were immunized with peptides in the presence of different T-cell epitopes. An immunodominant T-cell epitope of the MV-F protein was more efficient than a subdominant or a cryptic T-cell epitope in providing help to a non-linked B-cell epitope. There is both a ranking order of the amount of help which B-cell epitopes require and a ranking order for the help T-cell epitopes are able to provide. The capability of a T-cell epitope to provide help to a B-cell epitope correlated with its own immunogenicity, i.e. the intensity of the antibody response to the peptide representing the T-cell epitope. The data suggest that for each MHC class II allele there is an optimal T-cell epitope which can provide help to a maximal number of B-cell epitopes and that such a peptide can be identified by its ability to induce antibodies against itself. By using this strategy, the authors were able to induce antibodies which cross-reacted with the MV.

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BACKGROUNDFresh-frozen plasma (FFP) may contain antibodies to hepatitis B surface antigen (HBsAg, anti-HBs). These anti-HBs may lead to a misinterpretation of the actual hepatitis B immune status. Furthermore, they may not only confer protection against hepatitis B virus (HBV), but may also favor the selection of HBsAg mutants.CASE REPORTWe report a case of de novo HBV infection in a HBV-naïve recipient with alcoholic liver disease, who received a liver from a donor with antibodies to hepatitis B core antigen (HBcAg, anti-HBc) and anti-HBs.RESULTSA lookback investigation revealed the following: 1) Due to anti-HBs passively acquired through FFP, the recipient was considered immune to HBV and did not receive anti-HBV prophylaxis. 2) Within 1 year after transplantation he developed hepatitis B in absence of any elevated liver enzymes after the anti-HBs by FFP declined. 3) Despite an infection with HBV-containing wild-type HBcAg, the patient did not seroconvert to anti-HBc positivity. 4) The replicating HBV encoded two HBsAg mutations, first sQ129R and 4 months later sP127S. They map to the highly conserved “α” determinant of the HBsAg loop.CONCLUSION1) Passive transfer of anti-HBs from FFP led to an erroneous pretransplant diagnosis of HBV immunity when the patient was in fact HBV-naïve. 2) HBsAg mutations might have been selected in escape from donor's actively produced anti-HBs and the recipient's anti-HBs by FFP might have favored this selection. 3) It is doubtful whether hepatitis B immunoglobulin could have prevented the reactivation. 4) Antiviral prophylaxis would have been crucial.

Legionella spp. are an important cause of pulmonary and rarely extrapulmonary infections. L. cincinnatiensis has only been implicated in five cases to date. We herein report the first case of L. cincinnatiensis septic arthritis in a 90-year old lady with a past medical history of chronic kidney disease. She developed septic arthritis of her left wrist after having received intraarticular corticosteroid injections and oral corticosteroids administered for presumed chondrocalcinosis. Appropriate antimicrobial treatment of L. cincinnatiensis septic arthritis was delayed until identification of this organism in joint biopsies by broad-range bacterial PCR targeting the 16S rRNA gene with subsequent rDNA sequence analysis and by culture on special media. Reviewing all reported cases of septic arthritis caused by Legionella spp. other than L. cincinnatiensis it is notable that diagnosis was established by PCR in the majority of cases and only subsequently confirmed by special culture. Although most patients were immunosuppressed, outcome was favourable. Treatment consisted of a fluoroquinolone alone or in combination with rifampicin or a macrolide. Our case highlights the need for a high index of suspicion for infections with unusual/fastidious organisms when symptoms are suggestive of septic arthritis but conventional methods fail to identify a causative organism.

Background and objectives: Anogenital warts (AGWs) are most commonly caused by low-risk human papillomavirus (HPV) types, and although they are the most frequent viral sexually transmitted infections (STIs), little is known about STI coinfections in affected patients. We therefore sought to assess STI coinfection rates in patients with AGW, specify STI coinfections and calculate the number needed to screen (NNS) for each STI. Methods:A retrospective cross-sectional study analyzing data sets from AGW patients treated in our clinic between 2008-2016.Results: 142/196 (72 %) patients had been variably screened for infections with HIV, HBV and HCV, Treponema pallidum, Neisseria gonorrhoeae, Chlamydia trachomatis, Mycoplasma genitalium and HSV. The STI coinfection rate in all tested patients was 24.6 %, yielding an NNS of 4.1 to detect any STI. Of note, the coinfection rate did not differ significantly between heterosexual men, homosexual men and women, respectively. The NNS for syphilis was 8.4, for HIV 14.0, for HCV 28.5 and for HBV 39.0. The NNS for asymptomatic patients tested for HSV, Chlamydia trachomatis and Mycoplasma genitalium were 1.4, 5.3 and 12.0, respectively.Conclusion: Due to the high prevalence of STI coinfections, AGW patients should be screened for other STIs.

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