Publications by authors named "John Stenos"

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  • The study examines how the Barwon South-West Public Health Unit managed COVID-19 cases during 2020, focusing on their operational model and the impact of community transmission.
  • Between March and October 2020, 575 confirmed cases were reported in the region, with a 4.7% hospitalization rate and a 1.7% fatality rate, particularly during a major outbreak in Wave 2.
  • The local interprofessional model of care was effective in controlling outbreaks, leading to the elimination of the virus within three months and offering valuable insights for future public health strategies in Victoria.
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  • Query fever, caused by the bacterium Coxiella burnetii, often presents as an influenza-like illness (ILI), making it easy to overlook in low-endemic areas where other common illnesses like COVID-19 are more prevalent.
  • A study tested 542 serum samples from patients aged 10-70 in New South Wales with undiagnosed probable ILI, finding only one case (0.2%) of missed acute Q fever, while 9.6% of 731 tests initiated by clinicians were positive during the same period.
  • The findings suggest that Q fever is more likely to be diagnosed through clinician-requested tests rather than incidental screening of patients with ILI symptoms.
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Macropods are often implicated as the main native Australian reservoir hosts of (Q fever); however, the maintenance and transmission capacity of these species are poorly understood. The objective of this cross-sectional study was to describe the epidemiology of in a high-density population of eastern grey kangaroos () in a peri-urban coastal nature reserve in New South Wales, Australia. Blood, faeces and swabs were collected from forty kangaroos as part of a population health assessment.

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  • - The study examines the presence of rickettsial species in ticks and ruminants in western Iran, highlighting a lack of prior knowledge on the topic despite its clinical importance.
  • - Researchers collected 250 blood samples from sheep and goats alongside 244 ticks, using advanced molecular methods like qPCR to detect rickettsial DNA, finding a significant presence of these pathogens in ticks.
  • - The findings, which showed rickettsial DNA in 53.7% of the tick samples and no presence in ruminant blood, suggest a need for increased awareness and monitoring of rickettsioses in Iran's public health system.
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Coxiella burnetii, the causative agent of Q fever, is a zoonotic bacteria of global public health significance. The organism has a complex, diverse, and relatively poorly understood animal reservoir but there is increasing evidence that macropods play some part in the epidemiology of Q fever in Australia. The aim of this cross-sectional survey was to estimate the animal- and tissue-level prevalence of coxiellosis amongst eastern grey (Macropus giganteus) and red (Osphranter rufus) kangaroos co-grazing with domestic cattle in a Q fever endemic area in Queensland.

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Introduction: Rickettsia spp. and Orientia spp. are the causes of neglected infections that can lead to severe febrile and systemic illnesses in humans.

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Coxiella burnetti is an intracellular bacterium that causes Q fever, a disease of worldwide importance. Q-VAX , the approved human Q fever vaccine, is a whole cell vaccine associated with safety concerns. Here a safe particulate subunit vaccine candidate is developed that is ambient-temperature stable and can be cost-effectively manufactured.

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  • Whipple disease (WD) is a rare infection caused by the bacterium Tropheryma whipplei, primarily affecting genetically predisposed individuals.
  • Researchers developed an immunofluorescence serological assay to detect antibodies against T. whipplei to help rule out WD in patients being evaluated for the disease.
  • In a study comparing 16 WD patients with 156 controls, low antibody titres were found in WD patients, and the assay demonstrated 91% specificity for excluding the disease, which could improve with further validation in diverse populations.
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  • Q fever is a disease caused by a bacterium that poses risks to people working in animal-related jobs and those in contact with wildlife.
  • While many people experience no symptoms, about 5% of those who do can develop serious long-term health issues, such as endocarditis.
  • The review discusses how the immune response to Q fever can influence disease outcomes and highlights ongoing efforts to develop a safer, cost-effective vaccine, as the current vaccine (Q-VAX) can cause adverse reactions in those previously exposed.
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Rickettsia felis is an emerging flea-borne spotted fever pathogen that causes febrile illness in humans. In Vietnam, R. felis was detected in hospitalized patients, but there is no information on its presence in the Vietnamese community.

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Q fever is an infectious zoonotic disease, caused by the Gram-negative bacterium Coxiella burnetii. Transmission occurs from livestock to humans through inhalation of a survival form of the bacterium, the Small Cell Variant, often via handling of animal parturition products. Q fever manifests as an acute self-limiting febrile illness or as a chronic disease with complications such as vasculitis and endocarditis.

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Rickettsia felis, a zoonotic vector-borne bacteria, is reported globally in humans, animals, and its invertebrate hosts. This study was designed to detect antibodies against R. felis and the DNA of R.

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The obligate intracellular bacterial pathogen has been identified in a few species of marine mammals, some of which are showing population declines. It has been hypothesized that in marine mammals is a distinct genotype that varies significantly from the typical terrestrial genotypes. It appears to lack an IS1111.

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Ticks and tick-borne pathogens pose a significant threat to the health and welfare of humans and animals. Our knowledge about pathogens carried by ticks of Australian wildlife is limited. This study aimed to characterise ticks and tick-borne microorganisms from a range of wildlife species across six sites in Victoria, Australia.

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Recently, has been described as a novel pathogen potentially contributing to decreased pup production in Australian fur seals (AusFS, ). Pacific gulls (PGs, ) are known to scavenge AusFS placental material during the fur seal breeding season. It is hypothesized that PGs may act as vectors for this pathogen.

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In Australia, there is a paucity of data about the extent and impact of zoonotic tick-related illnesses. Even less is understood about a multifaceted illness referred to as Debilitating Symptom Complexes Attributed to Ticks (DSCATT). Here, we describe a research plan for investigating the aetiology, pathophysiology, and clinical outcomes of human tick-associated disease in Australia.

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  • - The study investigated the genetic diversity of the zoonotic agent linked to Q fever in Iran, as no previous data was available on its genotypes there.
  • - Researchers confirmed 14 positive samples from sheep, goats, and cattle using quantitative polymerase chain reaction (qPCR) and amplified ten specific genetic spacers for further analysis.
  • - The findings revealed two new alleles leading to four novel MST genotypes and one previously identified genotype, indicating a diverse circulation of these genotypes among Iranian domestic ruminants, which is crucial for managing Q fever outbreaks.
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Q fever is caused by the bacterium and is spread to humans from infected animals especially goats, sheep and cattle, predominantly when giving birth. There is an effective human vaccine (Q-VAX) against Q fever, and although Q fever is a worldwide problem, the vaccine is only used in Australia due to difficulties associated with its use and the risk of adverse reactions. The desire to protect humans, particularly farmers and abattoir workers, from Q fever prompted the development of a new safe and effective human vaccine without all the difficulties associated with the current vaccine.

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is the causative agent of Mediterranean spotted fever (MSF). Misdiagnosis of MSF may occur with febrile syndromes associated with rash and thrombocytopenia, such as Crimean-Congo hemorrhagic fever (CCHF). This study aimed to determine the prevalence of among serum samples obtained from 260 suspected CCHF patients with features of MSF in Iran (2018-2020).

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Scrub typhus is a common bacterial infection in Asia caused by . This serological cohort study estimated the incidence of infection in a rural population in South India. Participants were enrolled through systematic sampling in 46 villages at baseline, and revisited the following year.

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Leptospirosis is among the most important zoonotic diseases in (sub-)tropical countries. The research objective was to evaluate the accuracy of the Serion IgM ELISA EST125M against the Microscopic Agglutination Test (MAT = imperfect reference test); to assess its ability to diagnose acute leptospirosis infections and to detect previous exposure to leptospires in an endemic setting. In addition, to estimate the overall Leptospira spp.

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Kangaroos are considered to be an important reservoir of Q fever in Australia, although there is limited knowledge on the true prevalence and distribution of coxiellosis in Australian macropod populations. Serological tests serve as useful surveillance tools, but formal test validation is needed to be able to estimate true seroprevalence rates, and few tests have been validated to screen wildlife species for Q fever. In this study, we modified and optimized a phase-specific indirect immunofluorescence assay (IFA) for the detection of IgG antibodies against Coxiella burnetii in macropod sera.

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Host biomarkers are increasingly being considered as tools for improved COVID-19 detection and prognosis. We recently profiled circulating host-encoded microRNA (miRNAs) during SARS-CoV-2 infection, revealing a signature that classified COVID-19 cases with 99.9% accuracy.

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Article Synopsis
  • - A 61-year-old man in a southeastern Iranian village died from Mediterranean spotted fever, which led to septic shock.
  • - He had a recent history of being bitten by a tick, which is how the infection likely started.
  • - Genetic analysis confirmed that he was infected with the Rickettsia conorii subspecies israelensis bacterium.
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Rickettsioses are arthropod-borne zoonotic diseases, several of which occur in Australia. This study aimed to assess the exposure levels and risk factors for spp. among Australian wildlife rehabilitators (AWRs) using serology, PCR and a questionnaire.

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