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1.
Article in English | MEDLINE | ID: mdl-38874302

ABSTRACT

INTRODUCTION: Communication and collaboration are integral in radiation oncology practice. A recently published qualitative study identified several deficiencies in skills development for Australian/New Zealand trainees. We aim to validate these findings to guide curriculum development. METHODS: A quantitative survey was developed through an iterative process, using themes identified in the previous qualitative investigation. This survey was distributed to radiation oncologists and trainees across Australia and New Zealand via email. Data collection and management utilised the REDCap system. Question types varied to maximise richness of data, including ranking, likert-scales and free-text questions. Results are primarily reported descriptively. RESULTS: Totally 35 participants submitted completed survey responses with broad representation across geography, gender and clinician seniority. To learn communication, participants reported strong preferences towards informal observation (60% agreement) and self-reflection (49% agreement), and against online learning (77% disagreement) methodologies. Nearly 35% acknowledge poor communication at least weekly, with time pressure being a major barrier (63% agreement). Clinical uncertainty and existing patient/family assumptions (both 74% agreement) contribute to difficulties in breaking bad news, with online learning being the only negatively perceived training modality (23% agreement). No participants reported any formal training/mentoring in multi-disciplinary team (MDT) engagement. Conflict was commonly witnessed/experienced (97%) and 26% of participants avoid MDTs due to difficulties experienced. CONCLUSIONS: This study validates the themes previously identified. We identified a strong preference for informal learning methodologies and against online modules, discordant to published literature. Effective collaboration within MDTs is identified as a particular area of need. We recommend future curriculum modification considers these results to maximise efficacy.

2.
PLoS Negl Trop Dis ; 18(4): e0011390, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38648254

ABSTRACT

Assay validation is an essential component of disease surveillance testing, but can be problematic in settings where access to positive control material is limited and a safety risk for handlers. Here we describe a single non-infectious synthetic control that can help develop and validate the PCR based detection of the viral causes of Crimean-Congo hemorrhagic fever, Ebola virus disease, Lassa fever, Marburg virus disease and Rift Valley fever. We designed non-infectious synthetic DNA oligonucleotide sequences incorporating primer binding sites suitable for five assays, and a T7 promotor site which was used to transcribe the sequence. Transcribed RNA was used as template in a dilution series, extracted and amplified with RT-PCR and RT-qPCR to demonstrate successful recovery and determine limits of detection in a range of laboratory settings. Our results show this approach is adaptable to any diagnostic assay requiring validation of nucleic acid extraction and/or amplification, particularly where sourcing reliable, safe material for positive controls is infeasible.


Subject(s)
Hemorrhagic Fevers, Viral , Humans , Hemorrhagic Fevers, Viral/diagnosis , Hemorrhagic Fevers, Viral/virology , RNA, Viral/genetics , Real-Time Polymerase Chain Reaction/methods , DNA Primers/genetics , Sensitivity and Specificity
3.
Viruses ; 16(4)2024 04 12.
Article in English | MEDLINE | ID: mdl-38675936

ABSTRACT

Domestic dogs are currently recognized as being infected by 25 different canine papillomavirus (CPV) types classified into three genera. A short sequence from a novel CPV type was amplified, along with CPV1, from a papilloma (wart) from the mouth of a dog. The entire 7499 bp genome was amplified, and CPV26 contained putative coding regions that were predicted to produce four early proteins and two late ones. The ORF L1 showed less than 62% similarity for all previously sequenced CPV types but over 69% similarity to multiple Omegapapillomavirus types from a variety of Caniform species including the giant panda, Weddel seal, and polar bear. Phylogenetic analysis confirmed CPV26 clusters within the Omegapapillomavirus genus. Specific primers were used to investigate the presence of CPV26 DNA within a series of 37 canine proliferative lesions. CPV26 DNA was amplified from one lesion, a cutaneous papilloma that also contained CPV6. This is the first time a PV type within the Omegapapillomavirus genus has been detected in a non-domestic species and this provides evidence that the omegapapillomaviruses infected a common ancestor of, and then co-evolved with, the Caniform species. Whether CPV26 causes disease is uncertain, but the absence of an E7 protein may suggest low pathogenicity.


Subject(s)
DNA, Viral , Dog Diseases , Genome, Viral , Papillomaviridae , Papillomavirus Infections , Phylogeny , Animals , Dogs , Papillomavirus Infections/virology , Papillomavirus Infections/veterinary , Papillomaviridae/genetics , Papillomaviridae/classification , Dog Diseases/virology , DNA, Viral/genetics , Open Reading Frames , Sequence Analysis, DNA
4.
Animals (Basel) ; 13(11)2023 Jun 02.
Article in English | MEDLINE | ID: mdl-37889803

ABSTRACT

A 14-year-old West Highland White terrier dog developed multiple raised plaques that were confined to the concave surface of the right pinna. Histology allowed a diagnosis of viral plaque, although the lesions contained some unusual microscopic features. A papillomaviral (PV) DNA sequence was amplified from the plaque using consensus PCR primers. The amplified sequence was used as a template to design 'outward facing' PCR primers, which allowed amplification of the complete PV DNA sequence. The sequence was 7778 bp and was predicted to code for five early genes and two late genes. The ORF L1 showed the highest (83.9%) similarity to CPV15, and phylogenetic analysis revealed the novel PV clustered with the species 3 ChiPVs. The novel PV was designated as canine papillomavirus (CPV) type 25. As CPV25 was not previously detected in a canine viral plaque, this PV type may be a rare cause of skin disease in dogs. However, as plaques that remain confined to the pinna were not previously reported in dogs, it is possible that CPV25 could be more common in plaques from this area of skin. The findings from this case expand the number of PV types that cause disease in dogs. Evidence from this case suggests that, compared to the other canine ChiPV types, infection by CPV25 results in viral plaques in atypical locations with unusual histological features.

5.
Vet Microbiol ; 284: 109813, 2023 Sep.
Article in English | MEDLINE | ID: mdl-37478511

ABSTRACT

Six Felis catus papillomavirus (FcaPV) types have been fully sequenceed from domestic cats including some that have been associated with the development of neoplasia. A sequence from a novel FcaPV type was amplified from a basal cell carcinoma that contained unusual histological evidence of PV infection and intense p16CDKN2A protein (p16) immunostaining. The entire 7467 bp genome was amplified using 'outward facing' primers. The PV was designated FcaPV7 and contained putative coding regions that were predicted to produce five early proteins and two late ones. The ORF L1 showed 77% similarity to that of FcaPV6. As the novel PV also showed greater than 60% similarity to three other feline Tau-PV types, FcaPV7 is proposed to be classified within this genus. Specific primers were designed but did not amplify FcaPV7 DNA from any of 60 samples from the mouth and skin of cats. FcaPV7 appears to rarely infect cats. However, FcaPV7 may be associated with skin cancer in this species.


Subject(s)
Cat Diseases , Papillomavirus Infections , Skin Neoplasms , Cats , Animals , DNA, Viral/genetics , Skin Neoplasms/veterinary , Papillomaviridae/genetics , Skin/pathology , Mouth , Papillomavirus Infections/veterinary , Cat Diseases/pathology
6.
Brachytherapy ; 22(5): 607-615, 2023.
Article in English | MEDLINE | ID: mdl-37423807

ABSTRACT

PURPOSE: Effective periprocedural analgesia is an important aspect of cervical brachytherapy delivery, with implications for patient comfort and attendance for subsequent fractions. We compared the efficacy and safety of three analgesic modalities: intravenous patient-controlled analgesia (IV-PCA), continuous epidural infusion (CEI) and programmed-intermittent epidural bolus with patient-controlled epidural analgesia (PIEB-PCEA). METHODS AND MATERIALS: Ninety-seven brachytherapy episodes involving 36 patients between July 2016 and June 2019 in a single tertiary center were retrospectively reviewed. Episodes were divided into two key phases: Phase 1 (while applicator remained in situ) and Phase 2 (following applicator removal until discharge or 4 h). For the primary endpoint, pain scores were retrieved and analyzed by analgesic modality with respect to median score and an internally defined "unacceptable" pain experience (>20% of scores being ≥4/10; i.e., moderate or greater). Total nonepidural oral morphine equivalent dose (OMED) and toxicity/complication events were reported as secondary endpoints. RESULTS: In Phase 1, there was a significantly higher median pain score (p < 0.001) and more episodes with unacceptable pain scores (46%) in the IV-PCA group compared with either epidural modality (6-14%; p < 0.001). In Phase 2, we observed a greater median pain score (p = 0.007) and higher proportion of patient episodes with unacceptable pain scores (38%) in the CEI group compared with both the IV-PCA (13%) and PIEB-PCEA (14%) groups (p = 0.001). There was a significant difference in median OMED used throughout all phases across the PIEB-PCEA (0 mg), IV-PCA (70 mg), and CEI (15 mg) groups (p < 0.001). CONCLUSIONS: PIEB-PCEA is safe and offers superior analgesia compared to IV-PCA or CEI for pain control after applicator placement in cervical brachytherapy.


Subject(s)
Analgesia, Epidural , Brachytherapy , Humans , Female , Anesthetics, Local , Retrospective Studies , Brachytherapy/methods , Analgesics/therapeutic use , Analgesia, Epidural/methods , Pain
7.
J Med Imaging Radiat Oncol ; 67(5): 556-563, 2023 Aug.
Article in English | MEDLINE | ID: mdl-37343171

ABSTRACT

INTRODUCTION: This study aimed to investigate the patterns of practices of radiation oncologists (ROs) and urologists in Australia and New Zealand with respect to the utilisation of post-prostatectomy radiation therapy (RT) and help guide the development of an update to the existing Faculty of Radiation Oncology Genito-Urinary Group post-prostatectomy guidelines. METHODS: ROs and urologists with subspecialty practice in prostate cancer from Australia and New Zealand were invited to participate in an online survey comprised of clinical scenarios regarding post-prostatectomy RT. RESULTS: Sixty-five ROs and 28 urologists responded to the survey. In the setting of low-risk biochemical relapse, the threshold for initiating RT was lower for ROs than urologists. ROs were more likely than urologists to recommend adjuvant RT for node-positive disease. When salvage RT was advised for a pT3N0R1 recurrence, there was no consensus amongst ROs on whether to add either ADT or nodal treatment over prostate bed RT alone. For a solitary PSMA-avid pelvic lymph node recurrence, whole pelvis RT with androgen deprivation therapy was the preferred treatment option (72% ROs, 43% urologists). Most ROs (92%) recommended conventionally fractionated RT to 66-70 Gy, with a boost to any PSMA PET avid recurrent disease. CONCLUSION: This survey highlights the marked discordance in practice for the management of prostate cancer relapse post-prostatectomy. This is seen not only between specialties but also within the radiation oncology community. This emphasises the need for an updated evidence-based guideline to be produced.


Subject(s)
Prostatic Neoplasms , Urologists , Male , Humans , Prostate/pathology , Prostatic Neoplasms/radiotherapy , Prostatic Neoplasms/surgery , Prostatic Neoplasms/pathology , Radiation Oncologists , New Zealand , Androgen Antagonists , Reactive Oxygen Species , Neoplasm Recurrence, Local/surgery , Prostatectomy , Salvage Therapy , Australia
8.
Front Cell Infect Microbiol ; 13: 1178576, 2023.
Article in English | MEDLINE | ID: mdl-37284498

ABSTRACT

Cryptosporidiosis is a worldwide diarrheal disease caused by the protozoan Cryptosporidium. The primary symptom is diarrhea, but patients may exhibit different symptoms based on the species of the Cryptosporidium parasite they are infected with. Furthermore, some genotypes within species are more transmissible and apparently virulent than others. The mechanisms underpinning these differences are not understood, and an effective in vitro system for Cryptosporidium culture would help advance our understanding of these differences. Using COLO-680N cells, we employed flow cytometry and microscopy along with the C. parvum-specific antibody Sporo-Glo™ to characterize infected cells 48 h following an infection with C. parvum or C. hominis. The Cryptosporidium parvum-infected cells showed higher levels of signal using Sporo-Glo™ than C. hominis-infected cells, which was likely because Sporo-Glo™ was generated against C. parvum. We found a subset of cells from infected cultures that expressed a novel, dose-dependent auto-fluorescent signal that was detectable across a range of wavelengths. The population of cells that expressed this signal increased proportionately to the multiplicity of infection. The spectral cytometry results confirmed that the signature of this subset of host cells closely matched that of oocysts present in the infectious ecosystem, pointing to a parasitic origin. Present in both C. parvum and C. hominis cultures, we named this Sig M, and due to its distinct profile in cells from both infections, it could be a better marker for assessing Cryptosporidium infection in COLO-680N cells than Sporo-Glo™. We also noted Sig M's impact on Sporo-Glo™ detection as Sporo-Glo™ uses fluoroscein-isothiocynate, which is detected where Sig M also fluoresces. Lastly, we used NanoString nCounter® analysis to investigate the transcriptomic landscape for the two Cryptosporidium species, assessing the gene expression of 144 host and parasite genes. Despite the host gene expression being at high levels, the levels of putative intracellular Cryptosporidium gene expression were low, with no significant difference from controls, which could be, in part, explained by the abundance of uninfected cells present as determined by both Sporo-Glo™ and Sig M analyses. This study shows for the first time that a natural auto-fluorescent signal, Sig M, linked to Cryptosporidium infection can be detected in infected host cells without any fluorescent labeling strategies and that the COLO-680N cell line and spectral cytometry could be useful tools to advance the understanding of Cryptosporidium infectivity.


Subject(s)
Cryptosporidiosis , Cryptosporidium parvum , Cryptosporidium , Humans , Cryptosporidium/genetics , Cryptosporidium parvum/genetics , Cryptosporidiosis/epidemiology , Transcriptome , Coloring Agents , Ecosystem , Diarrhea/epidemiology
9.
PLOS Glob Public Health ; 3(5): e0001527, 2023.
Article in English | MEDLINE | ID: mdl-37252910

ABSTRACT

Cryptosporidium and Giardia are major causes of diarrhoea globally, and two of the most notified infectious diseases in New Zealand. Diagnosis requires laboratory confirmation carried out mostly via antigen or microscopy-based techniques. However, these methods are increasingly being superseded by molecular techniques. Here we investigate the level of protozoa detection by molecular methods in campylobacteriosis cases missed through antigen-based assays and investigate different molecular testing protocols. We report findings from two observational studies; the first among 111 people during a Campylobacter outbreak and the second during normal surveillance activities among 158 people presenting with diarrhoea and a positive Campylobacter test, but negative Cryptosporidium and Giardia antigen-based test results. The molecular methods used for comparison were in-house end-point PCR tests targeting the gp60 gene for Cryptosporidium and gdh gene for Giardia. DNA extraction was performed with and without bead-beating and comparisons with commercial real-time quantitative (qPCR) were made using clinical Cryptosporidium positive sample dilutions down to 10-5. The Cryptosporidium prevalence was 9% (95% CI: 3-15; 10/111) and Giardia prevalence 21% (95% CI: 12-29; 23/111) in the 111 Campylobacter outbreak patients. The Cryptosporidium prevalence was 40% (95% CI: 32-48; 62/158) and Giardia prevalence 1.3% (95% CI: 0.2-4.5; 2/158) in the 158 routine surveillance samples. Sequencing identified Cryptosporidium hominis, C. parvum, and Giardia intestinalis assemblages A and B. We found no statistical difference in positive test results between samples using end-point PCR with or without bead-beating prior to DNA extraction, or between the in-house end-point PCR and qPCR. The qPCR Ct value was 36 (95% CI: 35-37) for 1 oocyst, suggesting a high limit of detection. In conclusion in surveillance and outbreak situations we found diagnostic serology testing underdiagnoses Cryptosporidium and Giardia coinfections in Campylobacter patients, suggesting the impact of protozoa infections may be underestimated through underdiagnosis using antigen-based assays.

10.
Infect Genet Evol ; 112: 105456, 2023 08.
Article in English | MEDLINE | ID: mdl-37257800

ABSTRACT

Picobirnaviruses are double-stranded RNA viruses known from a wide range of host species and locations but with unknown pathogenicity and host relationships. Here, we examined the diversity of picobirnaviruses from cattle and gorillas within and around Bwindi Impenetrable Forest National Park (BIFNP), Uganda, where wild and domesticated animals and humans live in relatively close contact. We use metagenomic sequencing with bioinformatic analyses to examine genetic diversity. We compared our findings to global Picobirnavirus diversity using clustering-based analyses. Picobirnavirus diversity at Bwindi was high, with 14 near-complete RdRp and 15 capsid protein sequences, and 497 new partial viral sequences recovered from 44 gorilla samples and 664 from 16 cattle samples. Sequences were distributed throughout a phylogenetic tree of globally derived picobirnaviruses. The relationship with Picobirnavirus diversity and host taxonomy follows a similar pattern to the global dataset, generally lacking pattern with either host or geography.


Subject(s)
Picobirnavirus , Humans , Animals , Cattle , Picobirnavirus/genetics , Phylogeny , RNA, Double-Stranded/genetics , Gorilla gorilla , Animals, Domestic
11.
J Wildl Dis ; 59(1): 202-206, 2023 01 01.
Article in English | MEDLINE | ID: mdl-36791463

ABSTRACT

Bats host several zoonotic pathogens. Island biogeography and epidemiologic theory predict small remote islands have lower infection diversity. Molecular studies of urine and feces from three species at 10 sites from three islands suggest multiple pathogenic Leptospira, but not coronavirus, paramyxovirus, or Histoplasma, circulate in isolated Pacific Fijian bat populations.


Subject(s)
Chiroptera , Coronavirus , Leptospira , Leptospirosis , Animals , Leptospirosis/veterinary , Phylogeny
12.
Viruses ; 14(11)2022 10 26.
Article in English | MEDLINE | ID: mdl-36366455

ABSTRACT

Numerous large dark plaques developed over the ventrum, legs and head of a 9-year-old pug dog over a 4-year-period. Histology confirmed a diagnosis of viral pigmented plaque and a short section of a novel papillomavirus (PV) type was amplified using consensus PCR primers. Taking advantage of the circular nature of PV DNA, 'outward facing' PCR primers allowed amplification of the full sequence. As this is the 24th PV known to infect dogs, the novel PV was designated canine papillomavirus (CPV) type 24. The CPV24 genome contained putative coding regions for 5 early proteins and 2 late ones. The CPV24 open reading frame L1 showed the highest (78.2%) similarity to CPV4 and phylogenetic analysis showed that CPV24 clustered with CPV4 and CPV16 suggesting CPV24 is the third species 2 Chipapillomavirus type identified in dogs. This is the third report of extensive pigmented plaques covering a high proportion of the skin. Both previous cases were caused CPV4 and, considering the high genetic similarity between CPV4 and CP24, infection by these CPV types may predispose to more severe clinical disease. In addition, as plaques caused by CPV16 appear more likely to progress to neoplasia, the detection of a species 2 Chipapillomavirus within a pigmented plaque may indicate the potential for more severe disease.


Subject(s)
Dog Diseases , Papillomavirus Infections , Dogs , Animals , Phylogeny , DNA, Viral/genetics , DNA, Viral/analysis , Papillomaviridae/genetics , Genomics , DNA Primers , Papillomavirus Infections/veterinary
13.
Infect Dis Poverty ; 11(1): 49, 2022 May 04.
Article in English | MEDLINE | ID: mdl-35509037

ABSTRACT

BACKGROUND: Giardia intestinalis is one of the most common causes of diarrhoea worldwide. Molecular techniques have greatly improved our understanding of the taxonomy and epidemiology of this parasite. Co-infection with mixed (sub-) assemblages has been reported, however, Sanger sequencing is sometimes unable to identify shared subtypes between samples involved in the same epidemiologically linked event, due to samples showing multiple dominant subtypes within the same outbreak. Here, we aimed to use a metabarcoding approach to uncover the genetic diversity within samples from sporadic and outbreak cases of giardiasis to characterise the subtype diversity, and determine if there are common sequences shared by epidemiologically linked cases that are missed by Sanger sequencing. METHODS: We built a database with 1109 unique glutamate dehydrogenase (gdh) locus sequences covering most of the assemblages of G. intestinalis and used gdh metabarcoding to analyse 16 samples from sporadic and outbreak cases of giardiasis that occurred in New Zealand between 2010 and 2018. RESULTS: There is considerable diversity of subtypes of G. intestinalis present in each sample. The utilisation of metabarcoding enabled the identification of shared subtypes between samples from the same outbreak. Multiple variants were identified in 13 of 16 samples, with Assemblage B variants most common, and Assemblages E and A present in mixed infections. CONCLUSIONS: This study showed that G. intestinalis infections in humans are frequently mixed, with multiple subtypes present in each host. Shared sequences among epidemiologically linked cases not identified through Sanger sequencing were detected. Considering the variation in symptoms observed in cases of giardiasis, and the potential link between symptoms and (sub-) assemblages, the frequency of mixed infections could have implications for our understanding of host-pathogen interactions.


Subject(s)
Coinfection , Giardia lamblia , Giardiasis , Coinfection/epidemiology , Disease Outbreaks , Feces/parasitology , Genetic Variation , Genotype , Giardia lamblia/genetics , Giardiasis/epidemiology , Giardiasis/parasitology , Glutamate Dehydrogenase/genetics , Humans , New Zealand/epidemiology
14.
PLoS One ; 16(11): e0254467, 2021.
Article in English | MEDLINE | ID: mdl-34818325

ABSTRACT

Cross-species transmission of pathogens is intimately linked to human and environmental health. With limited healthcare and challenging living conditions, people living in poverty may be particularly susceptible to endemic and emerging diseases. Similarly, wildlife is impacted by human influences, including pathogen sharing, especially for species in close contact with people and domesticated animals. Here we investigate human and animal contacts and human health in a community living around the Bwindi Impenetrable National Park (BINP), Uganda. We used contact and health survey data to identify opportunities for cross-species pathogen transmission, focusing mostly on people and the endangered mountain gorilla. We conducted a survey with background questions and self-reported diaries to investigate 100 participants' health, such as symptoms and behaviours, and contact patterns, including direct contacts and sightings over a week. Contacts were revealed through networks, including humans, domestic, peri-domestic, and wild animal groups for 1) contacts seen in the week of background questionnaire completion, and 2) contacts seen during the diary week. Participants frequently felt unwell during the study, reporting from one to 10 disease symptoms at different intensity levels, with severe symptoms comprising 6.4% of the diary records and tiredness and headaches the most common symptoms. After human-human contacts, direct contact with livestock and peri-domestic animals were the most common. The contact networks were moderately connected and revealed a preference in contacts within the same taxon and within their taxa groups. Sightings of wildlife were much more common than touching. However, despite contact with wildlife being the rarest of all contact types, one direct contact with a gorilla with a timeline including concerning participant health symptoms was reported. When considering all interaction types, gorillas mostly exhibited intra-species contact, but were found to interact with five other species, including people and domestic animals. Our findings reveal a local human population with recurrent symptoms of illness in a location with intense exposure to factors that can increase pathogen transmission, such as direct contact with domestic and wild animals and proximity among animal species. Despite significant biases and study limitations, the information generated here can guide future studies, such as models for disease spread and One Health interventions.


Subject(s)
Human-Animal Interaction , Parks, Recreational , Public Health , Zoonoses/transmission , Adult , Aged , Animals , Animals, Wild , Female , Health Surveys , Humans , Male , Middle Aged , Uganda , Young Adult
15.
Virology ; 563: 20-27, 2021 11.
Article in English | MEDLINE | ID: mdl-34411808

ABSTRACT

Viruses of the subfamily Orthocoronavirinae can cause mild to severe disease in people, including COVID-19, MERS and SARS. Their most common natural hosts are bat and bird species, which are mostly split across four virus genera. Molecular clock analyses of orthocoronaviruses suggested the most recent common ancestor of these viruses might have emerged either around 10,000 years ago or, using models accounting for selection, many millions of years. Here, we reassess the evolutionary history of these viruses. We present time-aware phylogenetic analyses of a RNA-dependent RNA polymerase locus from 123 orthocoronaviruses isolated from birds and bats, including those in New Zealand, which were geographically isolated from other bats around 35 million years ago. We used this age, as well as the age of the avian-mammals split, to calibrate the molecular clocks, under the assumption that these ages are applicable to the analyzed viruses. We found that the time to the most recent ancestor common for all orthocoronaviruses is likely 150 or more million years, supporting clock analyses that account for selection.


Subject(s)
Birds/virology , Chiroptera/virology , Coronaviridae Infections/virology , Coronaviridae , Genome, Viral , Animals , Coronaviridae/classification , Coronaviridae/genetics , Evolution, Molecular , New Zealand/epidemiology
16.
Acta Trop ; 220: 105969, 2021 Aug.
Article in English | MEDLINE | ID: mdl-34029530

ABSTRACT

Giardia duodenalis (syn. G. intestinalis and G. lamblia) is a protozoan parasite that cause disease (giardiasis) in humans and other animals. The pathogen is classified into eight assemblages, further divided into sub-assemblages, based on genetic divergence and host specificities. There are two zoonotic subtypes known as assemblages A and B, whilst assemblages from C to H are mainly found in domesticated animals, rodents and marine mammals. Here, we report for the first time the presence of assemblage E and sub-assemblage AIII in human isolates from the South Island in New Zealand. We identified a > 99% nucleotide similarity of assemblage E and sub-assemblage AIII with sequences of the gdh gene available in GenBank from individual human samples collected in Dunedin and Christchurch, respectively. We also performed a deep sequencing approach to assess intra-host assemblage variation. The sample from Dunedin showed evidence of mixed assemblage E and zoonotic sub-assemblage BIV. The report of two novel assemblages and mixed infections provides insights into the genetic diversity, epidemiology and transmission dynamics of Giardia duodenalis in New Zealand.


Subject(s)
Giardia lamblia/physiology , Giardiasis/epidemiology , Animals , Coinfection/epidemiology , Feces/parasitology , Genotype , Giardia lamblia/genetics , Giardia lamblia/isolation & purification , Humans , New Zealand/epidemiology
17.
Clin Infect Dis ; 73(7): e1570-e1578, 2021 10 05.
Article in English | MEDLINE | ID: mdl-32777036

ABSTRACT

BACKGROUND: Salmonella Enteritidis and Salmonella Typhimurium are major causes of bloodstream infection and diarrheal disease in East Africa. Sources of human infection, including the role of the meat pathway, are poorly understood. METHODS: We collected cattle, goat, and poultry meat pathway samples from December 2015 through August 2017 in Tanzania and isolated Salmonella using standard methods. Meat pathway isolates were compared with nontyphoidal serovars of Salmonella enterica (NTS) isolated from persons with bloodstream infections and diarrheal disease from 2007 through 2017 from Kenya by core genome multi-locus sequence typing (cgMLST). Isolates were characterized for antimicrobial resistance, virulence genes, and diversity. RESULTS: We isolated NTS from 164 meat pathway samples. Of 172 human NTS isolates, 90 (52.3%) from stool and 82 (47.7%) from blood, 53 (30.8%) were Salmonella Enteritidis sequence type (ST) 11 and 62 (36.0%) were Salmonella Typhimurium ST313. We identified cgMLST clusters within Salmonella Enteritidis ST11, Salmonella Heidelberg ST15, Salmonella Typhimurium ST19, and Salmonella II 42:r:- ST1208 that included both human and meat pathway isolates. Salmonella Typhimurium ST313 was isolated exclusively from human samples. Human and poultry isolates bore more antimicrobial resistance and virulence genes and were less diverse than isolates from other sources. CONCLUSIONS: Our findings suggest that the meat pathway may be an important source of human infection with some clades of Salmonella Enteritidis ST11 in East Africa, but not of human infection by Salmonella Typhimurium ST313. Research is needed to systematically examine the contributions of other types of meat, animal products, produce, water, and the environment to nontyphoidal Salmonella disease in East Africa.


Subject(s)
Salmonella typhimurium , Sepsis , Animals , Anti-Bacterial Agents , Cattle , Diarrhea/epidemiology , Humans , Meat , Multilocus Sequence Typing , Salmonella enteritidis/genetics , Salmonella typhimurium/genetics , Tanzania
18.
Curr Protoc Microbiol ; 59(1): e117, 2020 12.
Article in English | MEDLINE | ID: mdl-33034399

ABSTRACT

Giardia is an enteric protozoan parasite that causes gastroenteritis in all classes of vertebrates. It is ranked among the leading causes of death in children under 5 years of age. Giardiasis affects approximately 280 million people worldwide annually, a situation exacerbated by the low availability of effective treatments and the lack of a vaccine. In addition, the parasite is difficult to manipulate in in vitro environments, which hampers the development of effective disease management strategies. This article highlights the development of a method for the purification of viable Giardia cysts from fecal samples, verified by a trypan blue dye exclusion test. This protocol produces a 10-fold increase in yield over current methods. By combining sucrose flotation with gated filtration, the protocol significantly reduces the amount of debris in the purified cysts suspension. Cyst viability is verified by a trypan blue dye exclusion test. The ability to purify large quantities of Giardia from fecal samples could advance the development of effective treatments to target this worldwide prevalent parasite. © 2020 Wiley Periodicals LLC. Basic Protocol: Purification of Giardia cysts from fecal samples Support Protocol: Cyst viability test.


Subject(s)
Cysts/parasitology , Feces/parasitology , Giardia lamblia/isolation & purification , Parasitology/instrumentation , Parasitology/methods , Animals , DNA, Protozoan , Giardia/isolation & purification , Giardiasis/diagnosis , Giardiasis/parasitology , Humans , Sensitivity and Specificity
19.
Int J Parasitol Parasites Wildl ; 13: 160-170, 2020 Dec.
Article in English | MEDLINE | ID: mdl-33117650

ABSTRACT

In 2013 there was an outbreak of crusting ventral dermatitis among a group of juvenile rowi (Apteryx rowi), a species of the endangered New Zealand kiwi, that were being raised on an off-shore island sanctuary. Biopsies taken at the time found nematodes migrating within the epidermis of affected skin but the specific identity and origin of the organisms was not established, and sporadic cases of similar skin disease continue to occur on the island. On examination of additional sections from the original skin biopsies, adult nematodes and eggs were identified, the histomorphology of which was consistent with Capillaria sensu lato. PCR was performed on DNA extracted from archived formalin-fixed, paraffin-embedded tissue blocks of skin from eight affected rowi, using primers targeting the 18S region of nuclear ribosomal DNA and the COI gene of mitochondrial DNA of capillarid nematodes. The 18S sequences from all rowi samples were identical and matched sequences from members of the genus Eucoleus. In contrast, two distinct capillarid COI sequences were obtained, in one case both from the same rowi skin biopsy. While there were no close matches, both COI sequences also aligned nearest to sequences identified as Eucoleus spp. It is considered unlikely that two different nematode species are involved in the rowi skin lesions and the possible amplification of a COI pseudogene or "numt" is discussed. A species-level identification of the capillarid nematodes causing skin disease in rowi was not obtained, however based on histological evaluation the infections include reproductively-active adult nematodes. This finding indicates the possibility of perpetuation of the skin disease in the absence of the original source, as well as raising potential for the transfer of infection from the island when the juvenile rowi are translocated to their new habitats.

20.
Front Immunol ; 11: 1612, 2020.
Article in English | MEDLINE | ID: mdl-32793238

ABSTRACT

Understanding of the role of immunity in the regulation of cancer growth continues to rapidly increase. This is fuelled by the impressive results yielded in recent years by immune checkpoint inhibitors, which block regulatory pathways to increase immune-mediated cancer destruction. Exosomes are cell-secreted membranous nanoscale vesicles that play important roles in regulating physiological and pathophysiological processes. Cancer-derived exosomes (CDEXs) and their biologically-active cargos have been proven to have varied effects in malignant progression, including the promotion of angiogenesis, metastasis, and favorable microenvironment modification. More recently, there is an increasing appreciation of their role in immune evasion. In addition to CDEXs, there are immune-derived exosomes that facilitate communication between immune cells in the non-malignant setting. Investigation of cancer-mediated mechanisms behind interruption or modification of these normal exosomal pathways may provide further understanding of how malignant immune evasion is accomplished. Accumulating evidence indicates that immune-active CDEXs also have the potential to impact clinical oncological management. Whilst immune checkpoint inhibitors have well-established pharmacologically-targeted pathways involving the immune system, other widely used treatments such as radiation and cytotoxic chemotherapies do not. Thus, investigating exosomes in immunotherapy is important for the development of next-generation combination therapies. In this article, we review the ways in which CDEXs impact individual immune cell types and how this contributes to the development of immune evasion. We discuss the relevance of lymphocytes and myeloid-lineage cells in the control of malignancy. In addition, we highlight the ways that CDEXs and their immune effects can impact current cancer therapies and the resulting clinical implications.


Subject(s)
Cell-Derived Microparticles/metabolism , Exosomes/metabolism , Immunomodulation , Neoplasms/immunology , Neoplasms/metabolism , Animals , Biomarkers, Tumor , Cell Communication , Combined Modality Therapy , Disease Management , Humans , Immune Checkpoint Proteins/metabolism , Immunity, Innate , Neoplasms/pathology , Neoplasms/therapy , Treatment Outcome , Tumor Microenvironment
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