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The Lancet. Microbe Jul 2022Chlamydia psittaci can infect a wide range of avian species, occasionally causing psittacosis (also known as parrot fever) in humans. Most human psittacosis cases are...
BACKGROUND
Chlamydia psittaci can infect a wide range of avian species, occasionally causing psittacosis (also known as parrot fever) in humans. Most human psittacosis cases are associated with close contact with pet birds or poultry. In December, 2020, an outbreak of severe community-acquired pneumonia of unknown aetiology was reported in a hospital in Shandong province, China, and some of the patients' close contacts had respiratory symptoms. Our aims were to determine the causative agent of this epidemic and whether there had been human-to-human transmission.
METHODS
For this epidemiological and aetiological investigation study, we enrolled patients who had community-acquired pneumonia confirmed by chest CT at two local hospitals in Shandong Province in China. We collected sputum, bronchoalveolar lavage fluid, and nasopharyngeal swab samples from participants and detected pathogens by surveying for 22 target respiratory microbes using a commercial assay, followed by metagenomic next-generation sequencing, specific nested PCR, and qPCR tests. We excluded individuals who were C psittaci-negative on both tests. We recruited close contacts of the C psittaci-positive patients, and tested nasopharyngeal swabs from the close contacts and samples from ducks from the processing plant where these patients worked. We then integrated the epidemiological, clinical, and laboratory data to reveal the potential chain of transmission of C psittaci that characterised this outbreak.
FINDINGS
Between Dec 4 and 29, 2020, we used metagenomic next-generation sequencing and different PCR-based approaches to test 12 inpatients with community-acquired pneumonia, of whom six (50%) were workers at a duck-meat processing plant and two (17%) were unemployed people, who were positive for C psittaci and enrolled in this study. We contacted 61 close contacts of the six patients who worked at the duck-meat processing plant, of whom 61 (100%) were enrolled and tested, and we determined that the community-acquired pneumonia outbreak was caused by C psittaci. Within the outbreak cluster, 17 (77%) of 22 participants had confirmed C psittaci infections and five (23%) of 22 participants were asymptomatic C psittaci carriers. The outbreak had begun with avian-to-human transmission, and was followed by secondary and tertiary human-to-human transmission, which included transmission by several asymptomatic carriers and by health-care workers. In addition, some of the participants with confirmed C psittaci infection had no identified source of infection, which suggested cryptic bacterial transmission.
INTERPRETATION
Our study data might represent the first documented report of human-to-human transmission of C psittaci in China. Therefore, C psittaci has the potential to evolve human-to-human transmission via various routes, should be considered an elevated biosecurity and emergent risk, and be included as part of the routine diagnosis globally, especially for high-risk populations.
FUNDING
Academic Promotion Programme of Shandong First Medical University, National Science and Technology Major Project, ARC Australian Laureate Fellowship.
Topics: Animals; Australia; Birds; China; Chlamydophila psittaci; Community-Acquired Infections; Humans; Pneumonia; Psittacosis
PubMed: 35617977
DOI: 10.1016/S2666-5247(22)00064-7 -
Chinese Medical Journal Jan 2021
Topics: Chlamydophila psittaci; Humans; Pneumonia; Psittacosis
PubMed: 33410632
DOI: 10.1097/CM9.0000000000001313 -
The Clinical Respiratory Journal May 2023Conventional etiological detection and pathogenic antibody methods make it challenging to identify the atypical pathogens among the community-acquired pneumonia (CAP)....
INTRODUCTION
Conventional etiological detection and pathogenic antibody methods make it challenging to identify the atypical pathogens among the community-acquired pneumonia (CAP). Metagenomic next-generation sequencing (mNGS) could rapidly detect all potentially infectious diseases and identifies novel or potential pathogens.
METHODS
Eighteen patients diagnosed with atypical CAP were enrolled in this retrospective study, including nine Chlamydia psittaci pneumonia (C. p), four Legionella pneumonia (L. p) and five Mycoplasma pneumonia (M. p). We simultaneously tested bronchoalveolar lavage fluid (BALF) samples for conventional microbiological methods and mNGS, and blood specimens were analysed. We also collected and compared baseline and clinical characteristics and treatment responses.
RESULTS
Patients with C. p and L. p had similar symptoms, including fever, cough, headache, dyspnoea, asthenia, shivering and headache, compared with M. p, whose symptoms were slight. C. p and L. p usually showed multiple lobar distributions with pleural effusion. Serologic testing indicated that L. p had higher levels of white blood cells (WBCs), neutrophils, C-reactive protein (CRP), procalcitonin (PCT), alanine aminotransferase (ALT), lactate dehydrogenase (LDH) and creatinine compared with M. p and L. p (p < 0.05). However, patients with C. p had lower levels of albumin (p < 0.05), and M. p had a minimum risk of cardiac volume loads (p < 0.05). CD4/CD8 ratio, lymphocytes, aspartate aminotransferase (AST), creatine kinase (CK), cell counting of BALF and coagulation had no difference (p < 0.05). Pathogenic IgM assay showed that 4/5 cases were positive for M. p and no positive detection for C. p and L. p infection. We timely adjusted the antibiotics according to the final mNGS results. Eventually, 16/18 patients recovered fully. Conditions of L. p patients were worse than those of C. p patients, and those of M. p patients were the least.
CONCLUSION
Early application of mNGS detection increased the atypical pathogenic identification, improved the prognosis and made up for the deficiency of conventional detection methods.
Topics: Humans; Pneumonia, Mycoplasma; Chlamydophila psittaci; Legionella; Retrospective Studies; Pneumonia; Albumins
PubMed: 36929690
DOI: 10.1111/crj.13603 -
Journal of the American Veterinary... Dec 2002Considerable progress continues to be made in understanding chlamydial organisms, their host species, diagnosis, and treatment. (1-3) Thus, national guidelines are... (Review)
Review
Considerable progress continues to be made in understanding chlamydial organisms, their host species, diagnosis, and treatment. (1-3) Thus, national guidelines are updated annually to provide a standardized approach to handling infections in humans and birds. (2-3) Prior to development of these guidelines, considerable variation in approach by state agencies has been documented. (39) A more recent national assessment of state regulations and procedures has not been conducted. Decreasing imports of birds and increasing education may contribute to a reduction in human risk from avian infections. Keeping new birds separate from old birds in aviaries and poultry production facilities may reduce the incidence of avian chlamydiosis. Although wide-scale testing of birds may not be cost effective, (28) focal testing and treatment may help reduce human risk. The recent loss of a major source for pelleted feed for small birds, such as budgerigars, was a severe setback for veterinarians and local agencies in managing this disease. However, new medication formulas under development may help to address this problem. (2-3)
Topics: Animals; Bird Diseases; Birds; Chlamydophila psittaci; Disease Outbreaks; Humans; Mammals; Poultry; Psittacosis; Zoonoses
PubMed: 12494967
DOI: 10.2460/javma.2002.221.1710 -
Frontiers in Cellular and Infection... 2023Recently, the incidence of chlamydial pneumonia caused by rare pathogens such as or has shown a significant upward trend. The non-specific clinical manifestations and...
INTRODUCTION
Recently, the incidence of chlamydial pneumonia caused by rare pathogens such as or has shown a significant upward trend. The non-specific clinical manifestations and the limitations of traditional pathogen identification methods determine that chlamydial pneumonia is likely to be poorly diagnosed or even misdiagnosed, and may further result in delayed treatment or unnecessary antibiotic use. mNGS's non-preference and high sensitivity give us the opportunity to obtain more sensitive detection results than traditional methods for rare pathogens such as or .
METHODS
In the present study, we investigated both the pathogenic profile characteristics and the lower respiratory tract microbiota of pneumonia patients with different chlamydial infection patterns using mNGS.
RESULTS
More co-infecting pathogens were found to be detectable in clinical samples from patients infected with compared to , suggesting that patients infected with may have a higher risk of mixed infection, which in turn leads to more severe clinical symptoms and a longer disease course cycle. Further, we also used mNGS data to analyze for the first time the characteristic differences in the lower respiratory tract microbiota of patients with and without chlamydial pneumonia, the impact of the pattern of infection on the lower respiratory tract microbiota, and the clinical relevance of these characteristics. Significantly different profiles of lower respiratory tract microbiota and microecological diversity were found among different clinical subgroups, and in particular, mixed infections with and resulted in lower lung microbiota diversity, suggesting that chlamydial infections shape the unique lung microbiota pathology, while mixed infections with different may have important effects on the composition and diversity of the lung microbiota.
DISCUSSION
The present study provides possible evidences supporting the close correlation between chlamydial infection, altered microbial diversity in patients' lungs and clinical parameters associated with infection or inflammation in patients, which also provides a new research direction to better understand the pathogenic mechanisms of pulmonary infections caused by
Topics: Humans; Chlamydophila psittaci; Chlamydial Pneumonia; Coinfection; Chlamydia; Microbiota; Pneumonia; Chlamydia Infections; High-Throughput Nucleotide Sequencing
PubMed: 37434780
DOI: 10.3389/fcimb.2023.1157540 -
Revue Scientifique Et Technique... Dec 2011The aim of this study was to investigate the epidemiology of chlamydiosis in free-ranging asymptomatic and diarrhoeic sheep and goats in Egypt. Faecal swabs were...
The aim of this study was to investigate the epidemiology of chlamydiosis in free-ranging asymptomatic and diarrhoeic sheep and goats in Egypt. Faecal swabs were examined for the presence of Chlamydiae by culture in Vero cells and chick embryos, and staining with Giménez, direct fluorescein-conjugated monoclonal antibodies, and immunoperoxidase. Specific chlamydial DNA was identified by amplification of the omp2 gene. The asymptomatic goats were 50% positive for the presence of the omp2 gene of the family Chlamydiaceae, and all isolates were Chlamydophila psittaci. The percentage of diseased goats in which Chlamydiaceae were identified was 16.2%, and all were positive for Cp. psittaci. Of the asymptomatic sheep, 6.7% were positive for the omp2 gene of the family Chlamydiaceae, and again all were positive for Cp. psittaci. In contrast, 42.9% of the samples that were collected from the diseased sheep were positive for Chlamydiaceae, of which 25.7% were Cp. psittaci and 4.8% Cp. pecorum.
Topics: Animals; Bacterial Outer Membrane Proteins; Chick Embryo; Chlamydophila; Chlamydophila Infections; Chlamydophila psittaci; Chlorocebus aethiops; DNA, Bacterial; Egypt; Electrophoresis, Agar Gel; Feces; Fluorescent Antibody Technique, Direct; Goat Diseases; Goats; Immunoenzyme Techniques; Polymerase Chain Reaction; Polymorphism, Restriction Fragment Length; Psittacosis; Sheep; Sheep Diseases; Specific Pathogen-Free Organisms; Staining and Labeling; Vero Cells
PubMed: 22435204
DOI: 10.20506/rst.30.3.2088 -
Revue Scientifique Et Technique... Aug 2000Avian chlamydiosis (AC) can be economically devastating to producers and a serious public health problem. Most infections in humans are due to exposure to psittacine... (Review)
Review
Avian chlamydiosis (AC) can be economically devastating to producers and a serious public health problem. Most infections in humans are due to exposure to psittacine birds and pigeons; however, outbreaks resulting in severe disease and even death do occur in abattoir workers following processing of infected flocks. The disease occurs primarily in turkeys and ducks, but can affect all types of poultry. In poultry, the disease varies from one producing high morbidity and mortality to one that is asymptomatic. Farm workers and abattoir workers are at risk following exposure to either extreme. Although outbreaks of AC have declined since the 1970s, some parts of the world are now experiencing a rise in incidence. Whether the initial decrease was due to changes in production methods or to the increased use of antibiotics is not known. The mechanism for introduction of the disease into a flock or area is poorly understood. Wild birds are often infected by the same strains as domestic flocks and are therefore thought to play a major role in introduction. Data also indicate that vertical transmission may occur. Persistently infected carrier birds are known to be a source of chlamydiosis in the pet bird industry, but have not been confirmed as a source of infection in poultry flocks.
Topics: Animals; Chlamydophila psittaci; Ducks; Humans; Poultry Diseases; Psittacosis; Turkeys; Zoonoses
PubMed: 10935270
DOI: No ID Found -
Clinical Microbiology and Infection :... Jan 2009Human psittacosis is a zoonotic infectious disease which is caused by the obligate intracellular bacterium Chlamydophila psittaci. Transmission of the disease usually... (Review)
Review
Human psittacosis is a zoonotic infectious disease which is caused by the obligate intracellular bacterium Chlamydophila psittaci. Transmission of the disease usually originates from close contact with infected birds, most frequently in the context of the poultry industry, and from contact with Psittaciformes (cockatoos, parrots, parakeets and lories). Due to a low awareness of the disease and a variable clinical presentation psittacosis is often not recognised as such by general practitioners. This review therefore gives an overview of the epidemiology, symptoms, diagnosis and possible treatments for psittacosis in humans. The current case definition for epidemiological surveillance, as issued by the CDC, is discussed, as well as the possible emergence of Cp. psittaci antibiotic-resistant strains. There is an urgent need for information and for awareness campaigns directed at professional health care workers and the general public. In addition, a broader use of new diagnostic methods in medical laboratories and the development of prophylactics are called for.
Topics: Adult; Animals; Birds; Child; Chlamydophila psittaci; Female; Humans; Pregnancy; Psittacosis; Zoonoses
PubMed: 19220335
DOI: 10.1111/j.1469-0691.2008.02669.x -
Annals of Palliative Medicine Jul 2021Psittacosis ranges from a mild illness to fulminant severe pneumonia with multi-organ failure. It's crucial to understand the clinical characteristics and identify risk...
BACKGROUND
Psittacosis ranges from a mild illness to fulminant severe pneumonia with multi-organ failure. It's crucial to understand the clinical characteristics and identify risk factors for a better outcome.
METHODS
We conducted a retrospective analysis designed to identify risk factors for severe Chlamydia psittaci pneumonia (C. psittaci pneumonia) by comparing the clinical characteristics of patients with severe and less severe forms of the disease. Epidemiological, clinical, laboratory, computed tomography (CT) imaging, and outcome data were collected.
RESULTS
We enrolled 27 patients with C. psittaci pneumonia, with a median age of 63 (range, 47-82) years, and 23 of whom (85.2%) had a history of avian exposure. Dyspnea was seen in 15 patients with severe C. psittaci pneumonia (100%), and four in 12 non-severe patients (33.3%) (P<0.01). Compared to non-severe patients, those with severe C. psittaci pneumonia had significantly higher levels of procalcitonin, urea nitrogen, lactate dehydrogenase, creatine kinase (CK), B natriuretic peptide (BNP), myoglobin, IL-6, and IL-10, as well as lower lymphocyte and CD8+ T cell counts, and PaO2/FiO2 ratio. Among patients with severe infection, CT showed that 46.7% had multi-lobar (more than two lobes) pneumonia, whereas its incidence was 0% in non-severe patients (P=0.01). Multivariate analysis revealed that the independent risk factors associated with severe C. psittaci pneumonia were abnormal CK (OR 15.2, 95% CI: 1.1-204.8, P=0.04) and BNP (OR 22.3, 95% CI: 1.8-281.9, P=0.02).
CONCLUSIONS
A history of prior avian exposure in middle-aged patients should serve as a clue in the diagnosis of C. psittaci pneumonia, and patients with its severe form are more likely to develop dyspnea and progress into respiratory failure, with involvement of multiple lung lobes. Abnormal CK and BNP levels are risk factors associated with severe C. psittaci pneumonia.
Topics: Aged; Aged, 80 and over; Chlamydophila psittaci; Humans; Middle Aged; Pneumonia; Psittacosis; Retrospective Studies; Risk Factors
PubMed: 34353090
DOI: 10.21037/apm-21-1502 -
Frontiers in Cellular and Infection... 2022The incidence of severe () pneumonia and coinfections is increasing. Early detection of this condition is needed to prevent negative outcomes, along with detailed...
The incidence of severe () pneumonia and coinfections is increasing. Early detection of this condition is needed to prevent negative outcomes, along with detailed descriptions of its associated clinical characteristics. Our study contributes by undertaking etiological analysis of patients with . pneumonia based on metagenomic next-generation sequencing (mNGS). A retrospective analysis of 30 patients with pneumonia was undertaken and confirmed by mNGS or polymerase chain reaction (PCR). Clinical manifestations of the severe and non-severe pneumonia groups were compared for clinical reference. Etiological analyses were also performed to comprehensively understand pathogeny and coinfection with other respiratory pathogens in patients. The absolute value of lymphocytes (LYM) in the severe group was lower than in the non-severe group. At the same time, neutrophil-to-lymphocyte ratio (NLR), procalcitonin (PCT), alanine aminotransferase (ALT), D-II polymer, brain natriuretic peptide (BNP), myoglobin (MYO), and cardiac troponin I (cTnI) were significantly higher ( < 0.05) in the severe group. mNGS has a broader pathogen spectrum and can more sensitively detect and other low-abundance pathogens with a higher positive detection rate (100%, 13/13 vs. 46%, 6/13, 0.05) than conventional culture methods. mNGS detected the following dominant species associated with in patients: bacteria (53.2%, 39% gram-positive, 61% gram-negative), fungi (12.9%), and viruses (33.9%). A total of 73.3% (11/15) of patients had suspected coinfections, with a coinfection rate of 91.7% (11/12) in the severe group. No coinfection or death occurred in the non-severe group. Prognosis in the severe group was poor, with a mortality rate of 27.3% (3/11) for patients with coinfection. Eight of 11 patients with coinfections (72.7%) recovered. In conclusion, the clinical symptoms of severe pneumonia manifested as abnormal inflammatory indicators, impaired liver function, myocardial injury, coagulation, and relatively low immune responses. The higher proportion of patients with coinfections in our study supports the use of mNGS for comprehensive early detection of respiratory infections in patients with pneumonia. Simultaneous early identification of coinfections would further improve the clinical treatment of these patients.
Topics: Humans; Chlamydophila psittaci; Retrospective Studies; Sensitivity and Specificity; Metagenomics; High-Throughput Nucleotide Sequencing; Pneumonia; Coinfection
PubMed: 36310873
DOI: 10.3389/fcimb.2022.1006117