Authors:Volker Micheel, Benedikt Hogan, Rivo Rakotoarivelo, Raphael Rakotozandrindrainy, Fetra Razafimanatsoa, Tsiriniaina Razafindrabe, Jean Rakotondrainiarivelo, Sabine Crusius, Sven Poppert, Norbert Schwarz, Jürgen May, Hagen Frickmann, and Ralf Hagen
This study assesses the nasal occurrence of β-lactamase-producing Enterobacteriaceae both in patients in a hospital department of infectious diseases at admission and in healthy Madagascan students and health care workers.Nasal swabs from 681 students, 824 health care workers, and 169 patients were obtained in Antananarivo, Madagascar, and transferred to Germany. Screening for β-lactamase (ESBL, ampC) producing Enterobacteriaceae was performed by cultural and molecular approaches, comprising Brilliance ESBL agar, E-testing, ABCD-testing, and commercial hyplex ESBL and SuperBug ID PCR.Regarding ESBL-positive strains and strains with resistance against at least three out of the four tested bactericidal antibiotic drugs, 0.3% (five out of 1541) of the students and health care workers group showed nasal colonization, whereas colonization was observed in 7.1% (12 out of 169) of the hospitalized patients at admission. No appreciably reduced detection rates after sample storage and intercontinental transport were observed.A considerable proportion of nasal colonization with cephalosporin-resistant Enterobacteriaceae was demonstrated in Madagascan hospital patients at admission, posing a risk of developing future endogenous infections. The nasal colonization of healthy individuals was negligible. Good storage and transport stability of Enterobacteriaceae will allow for future studies even in areas difficult to access.
Authors:Cosme Alvarado-Esquivel, Renata Vazquez-Morales, Edgar Colado-Romero, Ramiro Guzmán-Sánchez, Oliver Liesenfeld, and Jitender Dubey
We performed a cross-sectional study to determine the seroprevalence of Toxoplasma gondii infection in 308 domestic pigs slaughtered in La Paz, Baja California Sur State, Mexico using the modified agglutination test (MAT, cut off 1:25). Forty (13%) of the 308 pigs were seropositive with MAT titers of 1:25 in 16, 1:50 in 5, 1:100 in 4, 1:200 in 5, 1:400 in 3, 1:800 in 3, 1:1600 in 2, and 1:3200 in 2. Multivariate analysis of pigs’ characteristics showed that seropositivity to T. gondii was negatively associated with mixed breed (OR = 0.02; 95% CI: 0.003–0.26; P = 0.001). Other variables including sex, type of raising, and municipality did not show an association with T. gondii seropositivity by multivariate analysis. The frequency of high antibody titers (≥1:400) was significantly higher (P < 0.001) in Landrace pigs than mixed breed pigs. The seroprevalence of T. gondii infection in pigs for slaughter in Baja California Sur State is low compared with seroprevalences reported in pigs in other Mexican states. Landrace pigs demonstrated higher seroprevalence rates and antibody levels than mixed breed pigs. This is the first report of T. gondii infection in pigs raised in a desert climate.
Authors:Trudy Wassenaar, David Ussery, Lene Nielsen, and Hanne Ingmer
The qac genes of Staphylococcus species encode multidrug efflux pumps: membrane proteins that export toxic molecules and thus increase tolerance to a variety of compounds such as disinfecting agents, including quaternary ammonium compounds (for which they are named), intercalating dyes and some antibiotics. In Stapylococcus species, six different plasmid-encoded Qac efflux pumps have been described, and they belong to two major protein families. QacA and QacB are members of the Major Facilitator Superfamily, while QacC, QacG, QacH, and QacJ all belong to the Small Multidrug Resistance (SMR) family. Not all SMR proteins are called Qac and the reverse is also true, which has caused confusion in the literature and in gene annotations. The discovery of qac genes and their presence in various staphylococcal populations is briefly reviewed. A sequence comparison revealed that some of the PCR primers described in the literature for qac detection may miss particular qac genes due to lack of DNA conservation. Despite their resemblance in substrate specificity, the Qac proteins belonging to the two protein families have little in common. QacA and QacB are highly conserved in Staphylococcus species, while qacA was also detected in Enterococcus faecalis, suggesting that these plasmid-born genes have spread across bacterial genera. Nevertheless, these qacA and qacB genes are quite dissimilar to their closest homologues in other organisms. In contrast, SMR-type Qac proteins display considerable sequence variation, despite their short length, even within the Staphylococcus genus. Phylogenetic analysis of these genes identified similarity to a large number of other SMR members, found in staphylococci as well as in other genera. A number of phylogenetic trees of SMR Qac proteins are presented here, starting with genes present in S. aureus and S. epidermidis, and extending this to related genes found in other species of this genus, and finally to genes found in other genera.
Authors:Trudy M. Wassenaar, Anke Zschüttig, Claudia Beimfohr, Thomas Geske, Christian Auerbach, Helen Cook, Kurt Zimmermann, and Florian Gunzer
The probiotic product Symbioflor2 (DSM 17252) is a bacterial concentrate of six different Escherichia coli genotypes,
whose complete genome sequences are compared here, between each other as well as to other E. coli genomes. The genome
sequences of Symbioflor2 E. coli components contained a number of virulence-associated genes. Their presence seems to be
in conflict with a recorded history of safe use, and with the observed low frequency of adverse effects over a period of more than 6 years.
The genome sequences were used to identify unique sequences for each component, for which strain-specific hybridization probes were designed.
A colonization study was conducted whereby five volunteers were exposed to an exceptionally high single dose. The results showed that the probiotic
E. coli could be detected for 3 months or longer in their stools, and this was in particular the case for those components containing higher
numbers of virulence-associated genes. Adverse effects from this long-term colonization were absent. Thus, the presence of the identified
virulence genes does not result in a pathogenic phenotype in the genetic background of these probiotic E. coli.
The collection of epiphyllous bryophytes in the lowland rainforests of Phang-Nga province and in the neighbouring Phuket and Surat Thani provinces resulted in 54 liverwort and one moss species, of which 14 are new records for the bryoflora of Thailand. Epiphyllous bryophyte assemblages from nine localities are evaluated for species richness and beta diversity, as well as for their phytogeographical status.
Authors:Esther Fröhlich, R. Mayerhofer, and P. Holzer
With microbiome research being a fiercely contested playground in science, new data are being published at tremendous pace. The review at hand serves to critically revise four microbial metabolites widely applied in research: butyric acid, flagellin, lipoteichoic acid, and propionic acid. All four metabolites are physiologically present in healthy humans. Nevertheless, all four are likewise involved in pathologies ranging from cancer to mental retardation. Their inflammatory potential is equally friend and foe. The authors systematically analyze positive and negative attributes of the aforementioned substances, indicating chances and dangers with the use of pre- and probiotic therapeutics. Furthermore, the widespread actions of microbial metabolites on distinct organs and diseases are reconciled. Moreover, the review serves as critical discourse on scientific methods commonly employed in microbiome research and comparability as well as reproducibility issues arising thereof.
Authors:Miles Beaman, Mahdad Karimi, Meredith Hodge, Anthony Keil, and Peter Campbell
We assessed IgA antibodies and polymerase chain reaction (PCR) for diagnosis of pertussis in nasopharyngeal aspiration (NPA) samples from outpatients in Australia.A total of 1700 patients (849 adults, 851 children) from Western Australia and the Northern Territory fulfilled the laboratory case definition for pertussis between 2004 and 2013: 732 specimens were positive by NPA IgA alone, 559 by PCR alone, and 409 by both tests. Overall, 968 cases (56.8%) were positive by PCR and 1141 cases (67.2%) by IgA [p < 0.00025]. Among pediatric patients, PCR was positive in 524 (61.3%) and IgA in 569 (67%). In 849 adult cases, the respective proportions were 52.3% and 67.4% [p < 0.00025].The duration of cough in 507 patients was shorter in 262 pediatric cases (mean, 2.51 weeks; standard deviation [SD], 2.25) than 245 adult patients (3.27 weeks; SD, 2.79) [p = 0.0009]. PCR positivity showed a season-dependent variance (range, 5.6 to 85.9%) and peaked in the second week (71.7%) of illness. IgA antibodies peaked in the fifth week (89.5%) postinfection, and the positivity rate for NPA IgA was less variable (range, 38.3–97.2%).Nasopharyngeal Bordetella pertussis-specific IgA antibodies are valuable in diagnosis of pertussis in Australia. Reliance on PCR alone misses a significant proportion of pertussis cases, especially those with a delayed presentation.
Authors:Cosme Alvarado-Esquivel, Sandy Pacheco-Vega, Jesús Hernández-Tinoco, Diana Saldaña-Simental, Luis Sánchez-Anguiano, Misael Salcedo-Jáquez, Agar Ramos-Nevárez, Oliver Liesenfeld, José Márquez-Conde, Sandra Cerrillo-Soto, Lucio Martínez-Ramírez, and Carlos Guido-Arreola
The association of infection with Toxoplasma gondii and occupational exposure to animals has been scantly determined. We performed a case-control study with 200 subjects from Durango Province, Mexico, occupationally exposed to animals and 200 age- and gender-matched subjects without this occupation. Sera from all participants were analyzed for anti-T. gondii IgG and IgM antibodies using enzyme-linked immunoassays. The association of seroprevalence with sociodemographic, work, clinical, and behavioral characteristics in cases was determined.Cases and controls had similar frequencies of anti-T. gondii IgG antibodies (12/200: 6.0% and 11/200: 5.5%, respectively) (OR = 3.0; 95% CI: 0.12–73.64; P = 1.0). The frequency of sera with high (>150 IU/ml) levels of anti-T. gondii IgG antibodies was comparable among cases and controls (P = 0.61). Seroprevalence of anti-T. gondii IgM antibodies was similar in cases (4, 2.0%) than in controls (4, 2.0%) (P = 1.0). Multivariate analysis showed that seropositivity was associated with eating while working (OR = 7.14; 95% CI: 1.91–26.72; P = 0.003) and consumption of duck meat (OR = 5.43; 95% CI: 1.43–20.54; P = 0.01).No association between seropositivity to T. gondii and occupational exposure to animals was found. However, risk factors for infection found should be taken into account to reduce the exposure to T. gondii.
Authors:Olugbenga Olowe, Olufunmilola Makanjuola, Rita Olowe, and Daniel Adekanle
Vaginal infections in pregnancy are associated with considerable discomfort and adverse pregnancy outcomes including preterm delivery, low birth weight and increased infant mortality and also predisposition to HIV/AIDS. This study evaluated the prevalence and factors associated with vulvovaginal candidiasis, trichomoniasis and bacterial vaginosis among women attending antenatal clinic at a hospital in Nigeria. A semi-structured questionnaire was administered and high vaginal swab samples were obtained from consenting pregnant women. The samples were processed following standard protocols. The prevalence of vulvovaginal candidiasis was 36%, while those of trichomoniasis and bacterial vaginosis were 2% and 38%, respectively. Infections were higher in the third trimester and many women admitted to practices that increase risk of these infections. Significant association was found between recent intake of antibiotics and vaginal candidiasis, same association was also found with bacterial vaginosis. Adequate investigation and prompt treatment will reduce the morbidity and attendant effects of these prevalent infections on mother and fetus.