Transmission Dynamics of Bartonella sp. Strain OE 1-1 in Sundevall's Jirds (Meriones crassus)

ABSTRACTA high prevalence ofBartonellainfection is found in many natural systems; however, the transmission dynamics leading to observations of these infections is not fully understood. The capability ofXenopsylla ramesisfleas to serve as competent vectors ofBartonellasp. OE 1-1 (a strain closely related to the zoonoticBartonella elizabethae) toMeriones crassusjirds was investigated. NaïveX. ramesisfleas were placed for 72 h on naïve jirds or jirds that were either experimentally or naturally infected withBartonellasp. strain OE 1-1, after which they were placed on naïve jirds. Postfeeding, 69 to 100% of the fleas collected from eachBartonella-positive jird containedBartonellaDNA, and all naïve jirds became positive forBartonellasp. OE 1-1 after infestation with the infected fleas. In addition, maternal transmission ofBartonellasp. OE 1-1 in jirds was tested by mating 5Bartonella-positive and 5 naïve female jirds with 10 naïve male jirds in the absence of fleas. Fifteen offspring were delivered by each group. Cultures of blood drawn from all offspring on days 35 and 47 postdelivery were found to be negative forBartonella. A single spleen sample from the offspring of aBartonella-positive mother was found molecularly positive forBartonellasp. OE 1-1. This study demonstrates thatX. ramesisfleas are competent vectors ofBartonellasp. OE 1-1 toM. crassusjirds and indicates that maternal transmission is probably not the major transmission route from female jirds to their offspring. We suggest that the dynamics ofBartonellasp. OE 1-1 in theM. crassusjird population in nature is mostly dependent on its vectors.

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Prisoner’s insomnia prevalence, insomnia associated factors and interventions with sleep as an outcome: a review and narrative analysis

International Journal of Prisoner Health ◽

10.1108/ijph-01-2021-0014 ◽

2021 ◽

Vol ahead-of-print (ahead-of-print) ◽

Author(s):

Chris Griffiths ◽

Farah Hina

Keyword(s):

Narrative Analysis ◽

Associated Factors ◽

Behavioural Therapy ◽

Post Traumatic Stress ◽

Content Type ◽

Cognitive Behavioural ◽

High Prevalence ◽

Randomised Control Trials ◽

Post Traumatic ◽

Anxiety Depression

Purpose Insomnia is highly prevalent in prisoners. The purpose of this paper is a review of research evidence on interventions with sleep as an outcome (2000 to 2020) and rates of insomnia prevalence and associated factors in prisons (2015 to 2020). Design/methodology/approach An internet-based search used Medline, PubMed, PsycINFO (EBSCOhost), Embase, Web of Science and Scopus. Seven interventions and eight sleep prevalence or sleep-associated factor papers were identified. Findings Intervention research was very limited and the quality of the research design was generally poor. Interventions such as cognitive behavioural therapy for insomnia (CBT-I), yoga and mindfulness can be beneficial in a prison setting. This review identified a high prevalence of insomnia in prisons across the world, which was supported by recent evidence. Factors associated with insomnia include anxiety, depression, post-traumatic stress disorder, personality disorder and pain. Research limitations/implications There is a need for appropriately powered randomised control trials of CBT-I in prisons and a need to use objective measures of sleep quality. Originality/value Due to a lack of an up-to-date review, this paper fulfils the need for a review of the evidence on interventions in prison settings with sleep as an outcome, rates of insomnia prevalence and associated factors in prisons.

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Cross-Sectional Study Reveals High Prevalence of Clostridium difficile Non-PCR Ribotype 078 Strains in Australian Veal Calves at Slaughter

Applied and Environmental Microbiology ◽

10.1128/aem.03951-12 ◽

2013 ◽

Vol 79 (8) ◽

pp. 2630-2635 ◽

Cited By ~ 57

Author(s):

Daniel R. Knight ◽

Sara Thean ◽

Papanin Putsathit ◽

Stan Fenwick ◽

Thomas V. Riley

Keyword(s):

Clostridium Difficile ◽

Cross Sectional Study ◽

Sectional Study ◽

Cross Sectional ◽

Adult Cattle ◽

Content Type ◽

Retail Meats ◽

High Prevalence ◽

Pcr Ribotyping ◽

Ribotype 078

ABSTRACTRecent reports in North America and Europe ofClostridium difficilebeing isolated from livestock and retail meats of bovine origin have raised concerns about the risk to public health. To assess the situation in Australia, we investigated the prevalence and genetic diversity ofC. difficilein adult cattle and calves at slaughter. Carcass washings, gastrointestinal contents, and feces were collected from abattoirs across five Australian states. Selective culture, toxin profiling, and PCR ribotyping were performed. The prevalence ofC. difficilewas 56% (203/360 samples) in feces from <7-day-old calves, 3.8% (1/26) in 2- to 6-month-old calves, and 1.8% (5/280) in adult cattle. Three PCR ribotypes (RTs), RT127, RT033, and RT126, predominated in <7-day-old calves and comprised 77.8% (158/203 samples) of isolates. RT056, which has not been reported in cattle before, was found in 16 <7-day-old calves (7.7%). Surprisingly, RT078 strains, which dominate production animal carriage studies in the Northern Hemisphere, were not isolated.

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Anaplasma marginale Superinfection Attributable to Pathogen Strains with Distinct Genomic Backgrounds

Infection and Immunity ◽

10.1128/iai.02537-14 ◽

2014 ◽

Vol 82 (12) ◽

pp. 5286-5292 ◽

Cited By ~ 11

Author(s):

Eduardo Vallejo Esquerra ◽

David R. Herndon ◽

Francisco Alpirez Mendoza ◽

Juan Mosqueda ◽

Guy H. Palmer

Keyword(s):

High Throughput Sequencing ◽

Anaplasma Marginale ◽

Host Population ◽

Content Type ◽

Tropical Regions ◽

Disease Epidemiology ◽

Infectious Disease Epidemiology ◽

Perfect Sequence ◽

Significant Difference ◽

High Prevalence

ABSTRACTStrain superinfection occurs when a second pathogen strain infects a host already infected with a primary strain. The selective pressures that drive strain divergence, which underlies superinfection, and allow penetration of a new strain into a host population are critical knowledge gaps relevant to shifts in infectious disease epidemiology. In regions of endemicity with a high prevalence of infection, broad population immunity develops againstAnaplasma marginale, a highly antigenically variant rickettsial pathogen, and creates strong selective pressure for emergence of and superinfection with strains that differ in their Msp2 variant repertoires. The strains may emerge either bymsp2locus duplication and allelic divergence on an existing genomic background or by introduction of a strain with a differentmsp2allelic repertoire on a distinct genomic background. To answer this question, we developed a multilocus typing assay based on high-throughput sequencing of non-msp2target loci to distinguish among strains with different genomic backgrounds. The technical error level was statistically defined based on the percentage of perfect sequence matches of clones of each target locus and validated using experimental single strains and strain pairs. Testing ofA. marginale-positive samples from tropical regions whereA. marginaleinfection is endemic identified individual infections that contained unique alleles for all five targeted loci. The data revealed a highly significant difference in the number of strains per animal in the tropical regions compared to infections in temperate regions and strongly supported the hypothesis that transmission of genomically distinctA. marginalestrains predominates in high-prevalence areas of endemicity.

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Prediction of Local Transmission of Mycobacterium tuberculosis Isolates of a Predominantly Beijing Lineage by Use of a Variable-Number Tandem-Repeat Typing Method Incorporating a Consensus Set of Hypervariable Loci

Journal of Clinical Microbiology ◽

10.1128/jcm.01016-17 ◽

2017 ◽

Vol 56 (1) ◽

Author(s):

Yoshiro Murase ◽

Kiyohiko Izumi ◽

Akihiro Ohkado ◽

Akio Aono ◽

Kinuyo Chikamatsu ◽

...

Keyword(s):

Mycobacterium Tuberculosis ◽

Tandem Repeat ◽

Variable Number Tandem Repeat ◽

Variable Number ◽

Trend Test ◽

Typing Method ◽

Content Type ◽

Tuberculosis Transmission ◽

High Prevalence ◽

Hypervariable Loci

ABSTRACT Strain genotyping based on the variable-number tandem repeat (VNTR) is widely applied for identifying the transmission of Mycobacterium tuberculosis. A consensus set of four hypervariable loci (1982, 3232, 3820, and 4120) has been proposed to improve the discrimination of Beijing lineage strains. Herein, we evaluated the utility of these four hypervariable loci for tracing local tuberculosis transmission in 981 cases over a 14-month period in Japan (2010 to 2011). We used six different VNTR systems, with or without the four hypervariable loci. Patient ages and weighted standard distances (a measure of the dispersion of genotype-clustered cases) were used as proxies for estimating local tuberculosis transmission. The highest levels of isolate discrimination were achieved with VNTR systems that incorporated the four hypervariable loci (i.e., the Japan Anti-Tuberculosis Association [JATA]18-VNTR, mycobacterial interspersed repetitive unit [MIRU]28-VNTR, and 24Beijing-VNTR). The clustering rates by JATA12-VNTR, MIRU15-VNTR, JATA15-VNTR, JATA18-VNTR, MIRU28-VNTR, and 24Beijing-VNTR systems were 52.2%, 51.0%, 39.0%, 24.1%, 23.1%, and 22.0%, respectively. As the discriminative power increased, the median weighted standard distances of the clusters tended to decrease (from 311 to 80 km, P < 0.001, Jonckheere-Terpstra trend test). Concurrently, the median ages of patients in the clusters tended to decrease (from 68 to 60 years, P < 0.001, Jonckheere-Terpstra trend test). These findings suggest that strain typing using the four hypervariable loci improves the prediction of active local tuberculosis transmission. The four-locus set can therefore contribute to the targeted control of tuberculosis in settings with high prevalence of Beijing lineage strains.

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Toxoplasma gondii Development of Its Replicative Niche: in Its Host Cell and Beyond

Eukaryotic Cell ◽

10.1128/ec.00081-14 ◽

2014 ◽

Vol 13 (8) ◽

pp. 965-976 ◽

Cited By ~ 32

Author(s):

Ira J. Blader ◽

Anita A. Koshy

Keyword(s):

Toxoplasma Gondii ◽

Host Cell ◽

Host Cells ◽

Content Type ◽

Obligate Intracellular ◽

Cellular Processes ◽

High Prevalence ◽

Life Threatening ◽

Cell Processes ◽

Cellular Pathways

ABSTRACTIntracellular pathogens can replicate efficiently only after they manipulate and modify their host cells to create an environment conducive to replication. While diverse cellular pathways are targeted by different pathogens, metabolism, membrane and cytoskeletal architecture formation, and cell death are the three primary cellular processes that are modified by infections.Toxoplasma gondiiis an obligate intracellular protozoan that infects ∼30% of the world's population and causes severe and life-threatening disease in developing fetuses, in immune-comprised patients, and in certain otherwise healthy individuals who are primarily found in South America. The high prevalence ofToxoplasmain humans is in large part a result of its ability to modulate these three host cell processes. Here, we highlight recent work defining the mechanisms by whichToxoplasmainteracts with these processes. In addition, we hypothesize why some processes are modified not only in the infected host cell but also in neighboring uninfected cells.

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A Novel Method of Serum Resistance by Escherichia coli That Causes Urosepsis

mBio ◽

10.1128/mbio.00920-18 ◽

2018 ◽

Vol 9 (3) ◽

Cited By ~ 6

Author(s):

Carrie F. Coggon ◽

Andrew Jiang ◽

Kelvin G. K. Goh ◽

Ian R. Henderson ◽

Mark A. Schembri ◽

...

Keyword(s):

Escherichia Coli ◽

Urinary Tract ◽

Serum Resistance ◽

Gram Negative ◽

Content Type ◽

Bacterial Surface ◽

O Antigen ◽

High Prevalence ◽

Novel Method ◽

Inhibitory Antibodies

ABSTRACT Uropathogenic Escherichia coli (UPEC) is the most common cause of urinary tract infection, which in some patients can develop into life-threatening urosepsis. Serum resistance is a key virulence trait of strains that cause urosepsis. Recently, we identified a novel method of serum resistance in patients with Pseudomonas aeruginosa lung infections, where patients possessed antibodies that inhibited complement-mediated killing (instead of protecting against infection). These inhibitory antibodies were of the IgG2 subtype, specific to the O-antigen component of lipopolysaccharide (LPS) and coated the bacterial surface, preventing bacterial lysis by complement. As this mechanism could apply to any Gram-negative bacterial infection, we hypothesized that inhibitory antibodies may represent an uncharacterized mechanism of serum resistance in UPEC. To test this, 45 urosepsis patients with paired blood culture UPEC isolates were screened for serum titers of IgG2 specific for their cognate strain’s LPS. Eleven patients had sufficiently high titers of the antibody to inhibit serum-mediated killing of UPEC isolates by pooled healthy control sera. Depletion of IgG or removal of O-antigen restored sensitivity of the isolates to the cognate patient serum. Importantly, the isolates from these 11 patients were more sensitive to killing by serum than isolates from patients with no inhibitory antibodies. This suggests the presence of inhibitory antibodies may have allowed these strains to infect the bloodstream. The high prevalence of patients with inhibitory antibodies (24%) suggests that this phenomenon is an important mechanism of UPEC serum resistance. LPS-specific inhibitory antibodies have now been identified against three Gram-negative pathogens that cause disparate diseases. IMPORTANCE Despite improvements in the early detection and management of sepsis, morbidity and mortality are still high. Infections of the urinary tract are one of the most frequent sources of sepsis with Escherichia coli the main causative agent. Serum resistance is vital for bacteria to infect the bloodstream. Here we report a novel method of serum resistance found in patients with UPEC-mediated sepsis. Antibodies in sera usually protect against infection, but here we found that 24% of patients expressed “inhibitory antibodies” capable of preventing serum-mediated killing of their infecting isolate. Our data suggest that these antibodies would allow otherwise serum-sensitive UPEC strains to cause sepsis. The high prevalence of patients with inhibitory antibodies in this cohort suggests that this is a widespread mechanism of resistance to complement-mediated killing in urosepsis patients, invoking the potential for the application of new methods to prevent and treat sepsis.

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Africa’s vaccine deficit presents risks of variance

Emerald Expert Briefings ◽

10.1108/oxan-db264027 ◽

2021 ◽

Keyword(s):

Economic Recovery ◽

African Union ◽

Protective Measures ◽

Content Type ◽

High Transmission ◽

Self Sufficiency ◽

High Prevalence

Significance Both the WHO and African Union (AU) have called for a moratorium on booster shot programmes to allow more supply to flow to regions such as Africa, where vaccination numbers remain extremely low. Impacts High prevalence of co-morbidities such as HIV may require African nations to consider additional protective measures beyond vaccines. New cooperative initiatives across Africa represent a step towards self-sufficiency, but only if they are sustained. High transmission of new variants may force governments to consider new lockdowns, further slowing economic recovery.

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Respiratory Bacteria Stabilize and Promote Airborne Transmission of Influenza A Virus

mSystems ◽

10.1128/msystems.00762-20 ◽

2020 ◽

Vol 5 (5) ◽

Author(s):

Hannah M. Rowe ◽

Brandi Livingston ◽

Elisa Margolis ◽

Amy Davis ◽

Victoria A. Meliopoulos ◽

...

Keyword(s):

Influenza A Virus ◽

Influenza A ◽

Bacterial Species ◽

Bacterial Flora ◽

Transmission Dynamics ◽

Environmental Stability ◽

Upper Respiratory Tract ◽

Airborne Transmission ◽

Content Type ◽

Mortality And Morbidity

Infection with influenza A virus (IAV), especially when complicated with a secondary bacterial infection, is a leading cause of global mortality and morbidity. Gaining a greater understanding of the transmission dynamics of IAV is important during seasonal IAV epidemics and in the event of a pandemic. Direct bacterium-virus interactions are a recently appreciated aspect of infectious disease biology. Direct interactions between IAV and specific bacterial species of the human upper respiratory tract were found to promote the stability and infectivity of IAV during desiccation stress. Viral environmental stability is an important aspect during transmission, suggesting a potential role for bacterial respiratory communities in IAV transmission. Airborne transmission of IAV was abrogated upon depletion of nasal bacterial flora with topical antibiotics. This defect could be functionally complemented by S. pneumoniae coinfection. These data suggest that bacterial coinfection may be an underappreciated aspect of IAV transmission dynamics.

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Yellow fever in Brazil: thoughts and hypotheses on the emergence in previously free areas

Revista de Saúde Pública ◽

10.1590/s0034-89102010005000046 ◽

2010 ◽

Vol 44 (6) ◽

pp. 1144-1149 ◽

Cited By ~ 63

Author(s):

Pedro Fernando da Costa Vasconcelos

Keyword(s):

Yellow Fever ◽

Human Population ◽

Transmission Dynamics ◽

Southeastern Brazil ◽

Surveillance Program ◽

Genetic Lineage ◽

Rio Grande Do Sul ◽

Climate Conditions ◽

Factors Associated ◽

High Prevalence

This article describes and discusses factors associated to the reemergence of yellow fever and its transmission dynamics in the states of São Paulo (Southeastern Brazil) and Rio Grande do Sul (Southern) during 2008 and 2009. The following factors have played a pivotal role for the reemergence of yellow fever in these areas: large susceptible human population; high prevalence of vectors and primary hosts (non-human primates); favorable climate conditions, especially increased rainfall; emergence of a new genetic lineage; and circulation of people and/or monkeys infected by virus. There is a need for an effective surveillance program to prevent the reemergence of yellow fever in other Brazilian states.

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Stable Establishment of Cardinium spp. in the Brown Planthopper Nilaparvata lugens despite Decreased Host Fitness

Applied and Environmental Microbiology ◽

10.1128/aem.02509-19 ◽

2019 ◽

Vol 86 (4) ◽

Author(s):

Tong-Pu Li ◽

Chun-Ying Zhou ◽

Si-Si Zha ◽

Jun-Tao Gong ◽

Zhiyong Xi ◽

...

Keyword(s):

Cytoplasmic Incompatibility ◽

Developmental Stages ◽

Brown Planthopper ◽

Nilaparvata Lugens ◽

Hatching Rate ◽

Wild Populations ◽

Maternal Transmission ◽

Sogatella Furcifera ◽

Content Type ◽

Major Pest

ABSTRACT The brown planthopper Nilaparvata lugens (Hemiptera) is a major pest of rice crops in Asia. Artificial transinfections of Wolbachia have recently been used for reducing host impacts, but transinfections have not yet been undertaken with another important endosymbiont, Cardinium. This endosymbiont can manipulate the reproduction of hosts through phenotypes such as cytoplasmic incompatibility (CI), which is strong in the related white-backed planthopper, Sogatella furcifera (Hemiptera). Here, we stably infected N. lugens with Cardinium from S. furcifera and showed that it exhibits perfect maternal transmission in N. lugens. The density of Cardinium varied across developmental stages and tissues of the transinfected host. Cardinium did not induce strong CI in N. lugens, likely due to its low density in testicles. The infection did decrease fecundity and hatching rate in the transinfected host, but a decrease in fecundity was not apparent when transinfected females mated with Wolbachia-infected males. The experiments show the feasibility of transferring Cardinium endosymbionts across hosts, but the deleterious effects of Cardinium on N. lugens limit its potential to spread in wild populations of N. lugens in the absence of strong CI. IMPORTANCE In this study we established a Cardinium-infected N. lugens line that possessed complete maternal transmission. Cardinium had a widespread distribution in tissues of N. lugens, and this infection decreased the fecundity and hatching rate of the host. Our findings emphasize the feasibility of transinfection of Cardinium in insects, which expands the range of endosymbionts that could be manipulated for pest control.

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