Occurrence of pathogenic Mycobacteria avium and Pseudomonas aeruginosa in outdoor decorative fountain water and the associated microbial community.

Outdoor decorative fountains usually attract residents to visit. However, opportunistic pathogens (OPs) can proliferate and grow in the stagnant fountain water, posing potential health risks to visitors due to the inhalation of spaying aerosols. In this study, the abundance of selected OPs and associated microbial communities in three large outdoor decorative fountain waters were investigated using quantitative PCR and 16S rRNA sequencing. The results indicated that Mycobacteria avium and Pseudomonas aeruginosa were consistently detected in all decorative fountain waters throughout the year. Redundancy analysis showed that OPs abundance was negatively correlated with water temperature but positively correlated with nutrient concentrations. The gene copy numbers of M. avium varied between 2.4 and 3.9 log10 (gene copies/mL), which were significantly lower than P. aeruginosa by several orders of magnitude, reaching 6.5-7.1 log10 (gene copies/mL) during winter. The analysis of taxonomic composition and prediction of functional potential also revealed pathogenic microorganisms and infectious disease metabolic pathways associated with microbial communities in different decorative fountain waters. This study provided a deeper understanding of the pathogenic conditions of the outdoor decorative fountain water, and future works should focus on accurately assessing the health risks posed by OPs in aerosols.

Chest wall pseudotumor: a case of non-tuberculous mycobacterial infection.

BACKGROUND: Non-tuberculous mycobacterial (NTM) infections are increasing worldwide, making them an international public health problem. Surgical management is often indicated for localized infectious disease; however, most surgeons are unaware of the potential risks of transmission during surgery. CASE PRESENTATION: An 88-year-old Asian female was referred to our hospital for a tumor in the right lateral thoracic region. One month prior, she had a feeling of fullness and complained of localized pain and warmth in the right lateral thoracic wall. Pain and warmth gradually resolved without intervention; however, the fullness was getting worse. Computed tomography (CT) scan showed a mass of approximately 65 × 30 mm with an osteolytic change, involving the right 8th rib. Based on the rapid growth rate and CT findings, we strongly suspected a malignant chest wall tumor, and en bloc tumor resection with the 8th rib was performed. When the specimen was cut, a large amount of viscous pus was drained and its culture showed growth of Mycobacterium avium. Microscopically, the non-caseating epithelioid cell granuloma extended into the rib, infiltrating the bone cortex. On follow-up 1 month after discharge, there were no signs of infection or other adverse events associated with the surgery. CONCLUSIONS: Herein, we report about a patient with a mass diagnosed as an NTM abscess involving the rib cage, which was confused with a malignant tumor and eventually diagnosed following surgical excision. This report emphasizes the need to be aware of the possibility of NTM infection and take appropriate precautions if the patient has a rapidly growing mass in the chest wall.

Outbreak of avian mycobacteriosis in a commercial turkey breeder flock.

Avian mycobacteriosis (AM) is a chronic and contagious disease of pet birds, captive exotic, wild and domestic fowl, and mammals. Mycobacterium avium subsp. avium is the most common cause of AM in poultry. For the first time, we report a chronic outbreak of AM in an Iranian breeder flock of 250 45-week-old turkeys (Meleagris gallopavo) with a morbidity and mortality rate of 91.6% and 80%, respectively. A well-defined clinical feature of the outbreak included a progressive weight loss, decreased egg production, listlessness, and lameness. Tuberculous nodules were seen on liver, spleen, ovary, and ribs. Granulomatous inflammation and acid-fast bacilli were confirmed by using Ziehl-Neelsen method on hepatic lesions. M. avium subsp. avium was identified by polymerase chain reaction techniques based on the presence of 16S ribosomal RNA gene and insertion elements IS1245 and IS901. In this report, we not only describe the epidemiological, pathological, and molecular characteristics of the outbreak in detail, but we also discuss multiple factors influencing the introduction and development of AM critically. In this case, wild feral pigeons might have been the source of infection, but further molecular-epidemiology studies are needed to understand the role of wild birds in the persistence and transmission of Mycobacterium.RESEARCH HIGHLIGHTS First report of avian mycobacteriosis in an Iranian commercial turkey flock is described in detail.Risk factors intrinsic to the bird and mycobacteria, as well as extrinsic factors influencing the introduction and development of avian mycobacteriosis in birds, are critically discussed.

Successful treatment of an AIDS patient with prolonged Mycobacterium avium bacteremia, high HIV RNA, HBV infection, Kaposi's sarcoma and cytomegalovirus retinitis.

We report an AIDS patient with a high HIV RNA copy number in the plasma who was successfully treated for prolonged Mycobacterium avium bacteremia and other complications. An HIV-infected patient with high fever, anemia, high alkaline phosphatase, cystic lung lesions, hepatitis B virus infection and Kaposi's sarcoma was referred to our hospital. PCR of the blood revealed Mycobacterium avium bacteremia and the time to blood culture positivity was 8 days. The HIV-1 RNA copy number in the plasma was more than ten million copies/ml and the CD4-positive T cell count was 21 cells/µL. Although the high fever resolved five days after therapy for Mycobacterium avium was started, the fever recurred just before starting anti-retroviral therapy (ART) including dolutegravir. The patient experienced repeated but self-limiting bouts of severe inflammation. Mycobacteremia was intermittently detected up to 79 days, suggesting that the recurrent episodes of inflammation were due to the intermittent dissemination of mycobacteria, and that persistent treatment is needed. Five months after the beginning of ART, the HIV-1 RNA copy number in the plasma was still 28,000 copies/ml. An HIV drug-resistance test revealed sensitivity to all anti-retroviral drugs. Eleven months after the initiation of ART, the HIV RNA copy number in the plasma decreased to 45 copies/mL and the CD4-positive T cell count recovered to 205 cells/µL. Our case also suggests that dolutegravir can be effective in cases with prolonged high levels of HIV RNA. Our findings emphasize that prompt diagnosis and persistent therapy for mycobacterial infection are important for successful treatment.

Mycobacterium avium in Community and Household Water, Suburban Philadelphia, Pennsylvania, USA, 2010-2012.

Attention to environmental sources of Mycobacterium avium complex (MAC) infection is a vital component of disease prevention and control. We investigated MAC colonization of household plumbing in suburban Philadelphia, Pennsylvania, USA. We used variable-number tandem-repeat genotyping and whole-genome sequencing with core genome single-nucleotide variant analysis to compare M. avium from household plumbing biofilms with M. avium isolates from patient respiratory specimens. M. avium was recovered from 30 (81.1%) of 37 households, including 19 (90.5%) of 21 M. avium patient households. For 11 (52.4%) of 21 patients with M. avium disease, isolates recovered from their respiratory and household samples were of the same genotype. Within the same community, 18 (85.7%) of 21 M. avium respiratory isolates genotypically matched household plumbing isolates. Six predominant genotypes were recovered across multiple households and respiratory specimens. M. avium colonizing municipal water and household plumbing may be a substantial source of MAC pulmonary infection.

Chylous ascites, anti-interferon-gamma autoantibody, and angioimmunoblastic T-cell lymphoma: a rare but intriguing connection over Mycobacterium avium.

We report a case of non-AIDS (acquired immunodeficiency syndrome), non-CAPD (Continuous Ambulatory Peritoneal Dialysis), non-cirrhotic, Mycobacterium avium peritonitis, which is a rare form of mycobacterial infection. A 66-year-old Japanese man who had been treated previously for angioimmunoblastic T-cell lymphoma (AITL), had developed disseminated M. avium infection. Antimycobacterial regimen improved his symptoms; however, following an interruption in treatment, he developed chylous ascites. The patient died of uncontrolled peritonitis despite intensive treatment. Anti-interferon-γ autoantibody was positive, and AITL was presumed to be involved in autoantibody production. A rare coexistence of chylous ascites, autoantibody, and AITL taught us an intriguing lesson on the pathogenesis of M. avium infection. Particularly, we conclude that treatment strategies for M. avium infection should aim to restore immunity.

The sporadic nature of Legionella pneumophila, Legionella pneumophila Sg1 and Mycobacterium avium occurrence within residences and office buildings across 36 states in the United States.

AIM: Premise plumbing may disseminate the bacteria Legionella pneumophila and Mycobacterium avium, the causative agents for legionellosis and pulmonary nontuberculous mycobacterium disease respectively. METHODS AND RESULTS: Using quantitative PCR, the occurrence and persistence of L. pneumophila, L. pneumophila serogroup (Sg)1 and M. avium were evaluated in drinking water samples from 108 cold water taps (residences: n = 43) and (office buildings: n = 65). Mycobacterium avium, L. pneumophila and L. pneumophila Sg1 were detected 45, 41 and 25% of all structures respectively. Two occurrence patterns were evaluated: sporadic (a single detection from the three samplings) and persistent (detections in two or more of the three samples). CONCLUSIONS: The micro-organism's occurrence was largely sporadic. Office buildings were prone to microbial persistence independent of building age and square footage. Microbial persistence at residences was observed in those older than 40 years for L. pneumophila and was rarely observed for M. avium. The microbial occurrence was evenly distributed between structure types but there were differences in density and persistence. SIGNIFICANCE OF AND IMPACT OF THE STUDY: The study is important because residences are often suspected to be the source when a case of disease is reported. These data demonstrate that this may not be the case for a sporadic incidence.

Moxifloxacin resistance and genotyping of Mycobacterium avium and Mycobacterium intracellulare isolates in Japan.

BACKGROUND: Although fluoroquinolones are considered as alternative therapies of pulmonary Mycobacterium avium complex (MAC) disease, the association between fluoroquinolone resistance and MAC genotypes in clinical isolates from individuals not previously treated for MAC infection is not fully clear. METHODS: Totals of 154 M. avium isolates and 35 Mycobacterium intracellulare isolates were obtained from treatment-naïve patients with pulmonary MAC disease at the diagnosis of MAC infection at 8 hospitals in Japan. Their susceptibilities of moxifloxacin were determined by broth microdilution methods. Moxifloxacin-resistant isolates were examined for mutations of gyrA and gyrB. Variable numbers of tandem repeats (VNTR) assay was performed using 15 M. avium VNTR loci and 16 M. intracellulare VNTR loci. RESULTS: Moxifloxacin susceptibility was categorized as resistant and intermediate for 6.5% and 16.9%, respectively, of M. avium isolates and 8.6% and 17.1% of M. intracellulare isolates. Although the isolates of both species had amino acid substitutions of Thr 96 and Thr 522 at the sites corresponding to Ser 95 in the M. tuberculosis GyrA and Gly 520 in the M. tuberculosis GyrB, respectively, these substitutions were observed irrespective of susceptibility and did not confer resistance. The VNTR assays showed revealed three clusters among M. avium isolates and two clusters among M. intracellulare isolates. No significant differences in moxifloxacin resistance were observed among these clusters. CONCLUSIONS: Although resistance or intermediate resistance to moxifloxacin was observed in approximately one-fourth of M. avium and M. intracellulare isolates, this resistance was not associated with mutations in gyrA and gyrB or with VNTR genotypes.

Development of a LAMP assay for rapid and sensitive detection and differentiation of Mycobacterium avium subsp. avium and subsp. hominissuis.

Mycobacterium avium causes atypical mycobacterial infection in humans and animals worldwide. M. avium comprises the subspecies avium (MAA), hominissuis (MAH), silvaticum (MAS) and paratuberculosis (MAP). The M. avium complex (MAC), comprising M. avium and M. intracellulare, causes opportunistic infections of humans. M. avium subsp. avium (MAA) mainly causes avian tuberculosis while subsp. hominissuis (MAH) mainly infects pig. Distinguishing between these two subspecies is essential to the effective control of these atypical mycobacterial infections and minimization of the resulting economic loss. For this purpose, we developed a loop-mediated isothermal amplification (LAMP) assay that rapidly and sensitively detects and differentiates MAA and MAH. This MAA-LAMP assay targeting IS901 correctly detected four MAA isolates but did not detect 27 MAH and 19 non-MAA/non-MAH mycobacterial isolates. The MAAH-LAMP assay targeting IS1245 detected four MAA and 27 MAH isolates but not the other 19 mycobacterial isolates. We believe that implementation of this LAMP assay will significantly improve public health and safety. SIGNIFICANCE AND IMPACT OF THE STUDY: Mycobacterium avium, which is pathogenic for humans and animals, represents a continuing threat to public health and safety and to food production. Therefore, improved methods are urgently required to readily and efficiently identify M. avium subspecies. Compared with conventional PCR methods, the LAMP assay herein developed more rapidly detects and better distinguishes between two major M. avium subspecies that cause disease of pig. Importantly, this highly accurate and sensitive LAMP assay detects mycobacterial DNAs using real-time fluorescence or the unaided eye with a colour-change dye, making it ideal for translation to the clinic and slaughterhouse.

Use of slide scrape lysates for polymerase chain reaction confirmation of disseminated Mycobacterium avium infection in a cat.

Disseminated mycobacteriosis in a 3-year-old domestic medium-haired cat was diagnosed on lymph node cytology. Slide scrape lysates from the cytology submission were used to confirm Mycobacterium avium by polymerase chain reaction (PCR) and sequencing and proved a simple technique that could be a valuable tool in veterinary diagnostics and research.

Utilisation d'un lysat de grattage de lame pour la confirmation par amplification en chaîne par la polymérase d'une infection disséminée à Mycobacterium avium chez un chat. Une mycobactériose disséminée chez un chat domestique à poil moyen âgé de 3 ans a été diagnostiquée à l'aide d'une cytologie des ganglions lymphatiques. La soumission d'un lysat de grattage d'une lame provenant de la soumission de cytologie a été utilisé pour confirmer Mycobacterium avium par amplification en chaîne par la (PCR) et séquençage et elle s'est avérée une technique simple qui pourrait être un outil utile dans les diagnostics et la recherche vétérinaires.(Traduit par Isabelle Vallières).

Increase in Childhood Nontuberculous Mycobacterial Infections After Bacille Calmette-Guérin Coverage Drop: A Nationwide, Population-Based Retrospective Study, Finland, 1995-2016.

Background: Epidemiological data on childhood nontuberculous mycobacterial (NTM) disease is scarce and the protective effect of bacille Calmette-Guérin (BCG) vaccination remains debated. In 2006, the BCG policy in Finland changed from universal to selective. We aimed to study the effect of the BCG coverage decrease on the incidence of childhood NTM infections in Finland. Methods: We conducted a nationwide, population-based, retrospective study of NTM notifications recorded to the National Infectious Diseases Register between 1995 and 2016 and identified native-born children aged 0-4 years infected with NTM. Poisson log-linear model was used to estimate the change in the incidence rate of cohorts born during universal or selective BCG policy between 1995 and 2015. Results: We identified 97 native-born children aged <5 years infected with NTM (median age, 27 months; female-to-male ratio, 2:1). The most common species was Mycobacterium avium (n = 69 [71%]). The estimated incidence rates of NTM in universal-BCG and selective-BCG cohorts were 0.2 and 3.9 per 100000 person-years, respectively. The incidence rate ratio of selective-BCG cohorts compared to universal-BCG cohorts was 19.03 (95% confidence interval, 8.82-41.07; P < .001). Conclusions: After infant BCG coverage in Finland decreased, childhood NTM infections increased drastically. As there is no other apparent cause for the increase, this indicates that BCG offers protection against childhood NTM disease. This observation adds to the understanding of childhood NTM epidemiology and might explain why the disease is emerging in some countries.

Metal worker's lung: spatial association with Mycobacterium avium.

BACKGROUND: Outbreaks of hypersensitivity pneumonitis (HP) are not uncommon in workplaces where metal working fluid (MWF) is used to facilitate metal turning. Inhalation of microbe-contaminated MWF has been assumed to be the cause, but previous investigations have failed to establish a spatial relationship between a contaminated source and an outbreak. OBJECTIVES: After an outbreak of five cases of HP in a UK factory, we carried out blinded, molecular-based microbiological investigation of MWF samples in order to identify potential links between specific microbial taxa and machines in the outbreak zone. METHODS: Custom-quantitative PCR assays, microscopy and phylogenetic analyses were performed on blinded MWF samples to quantify microbial burden and identify potential aetiological agents of HP in metal workers. MEASUREMENTS AND MAIN RESULTS: MWF from machines fed by a central sump, but not those with an isolated supply, was contaminated by mycobacteria. The factory sump and a single linked machine at the centre of the outbreak zone, known to be the workstation of the index cases, had very high levels of detectable organisms. Phylogenetic placement of mycobacterial taxonomic marker genes generated from these samples indicated that the contaminating organisms were closely related to Mycobacterium avium. CONCLUSIONS: We describe, for the first time, a close spatial relationship between the abundance of a mycobacterium-like organism, most probably M. avium, and a localised outbreak of MWF-associated HP. The further development of sequence-based analytic techniques should assist in the prevention of this important occupational disease.

Gold nanoparticle-based probes for the colorimetric detection of Mycobacterium avium subspecies paratuberculosis DNA.

Gold nanoparticle (AuNP) is considered to be the most stable metal nanoparticle having the ability to be functionalized with biomolecules. Recently, AuNP-based DNA detection methods captured the interest of researchers worldwide. Paratuberculosis or Johne's disease, a chronic gastroenteritis in ruminants caused by Mycobacterium avium subsp. paratuberculosis (MAP), was found to have negative effect in the livestock industry. In this study, AuNP-based probes were evaluated for the specific and sensitive detection of MAP DNA. AuNP-based probe was produced by functionalization of AuNPs with thiol-modified oligonucleotide and was confirmed by Fourier-Transform Infrared (FTIR) spectroscopy. UV-Vis spectroscopy and Scanning Electron Microscopy (SEM) were used to characterize AuNPs. DNA detection was done by hybridization of 10 µL of DNA with 5 µL of probe at 63 °C for 10 min and addition of 3 µL salt solution. The method was specific to MAP with detection limit of 103 ng. UV-Vis and SEM showed dispersion and aggregation of the AuNPs for the positive and negative results, respectively, with no observed particle growth. This study therefore reports an AuNP-based probes which can be used for the specific and sensitive detection of MAP DNA.

Environmental Mycobacterium avium subsp. hominissuis have a higher probability to act as a recipient in conjugation than clinical strains.

Mycobacterium avium subsp. hominissuis (MAH) is a widespread opportunistic pathogen that can be isolated from environment (dust, soil and water) and patients with lung or lymphnode infection. In our previous research we revealed the pronounced genetic diversity in MAH by identifying eight different types of a newly described genomic island. In order to identify mechanisms of such horizontal gene transfer we now analyzed the ability of 47 MAH isolates to inherit the conjugative plasmid pRAW from M. marinum. A higher percentage of environmental isolates (22.7%) compared to clinical isolates (8%) had the capacity to function as recipient in conjugal plasmid transfer. Genetic analysis showed additionally that environmental isolates contained more genes homologous to genes present on conjugative mycobacterial plasmids than clinical isolates. Comparative analysis of the genomes of the isolates pointed to a possible association between the ability to act as recipient in conjugation and the structure of a genomic region containing the radC gene and a type I restriction/modification system. Finally we found that uptake of pRAW decreased the resistance against various antibiotics.

Identification and genetic characterization of polyomaviruses in estrildid and fringillid finches.

Polyomavirus infections were detected in 40 companion bird individuals belonging to a broad species range of estrildid and fringillid finches and originating from 21 different bird aviaries. Based on partial virus protein 1 (VP1) sequences, the viruses were identified as Serinus canaria polyomavirus 1 and Pyrrhula pyrrhula polyomavirus 1. Serinus canaria polyomavirus 1 was found in 18 birds belonging to one estrildid and four fringillid species. Pyrrhula pyrrhula polyomavirus 1 was detected in 22 birds of six estrildid and three fringillid species. There was a large overlap in host range. Increased mortality was frequently found in the affected bird aviaries while clinical signs were diverse. Co-infections with other viruses, bacteria or fungal pathogens were common and might have influenced the clinical signs. Sequence analyses, including partial VP1 sequences of the 40 virus strains, and full genome sequences of selected strains revealed a high genetic heterogeneity among virus subgroups of Serinus canaria polyomavirus 1 and Pyrrhula pyrrhula polyomavirus 1, indicating the existence of two virus variants for both virus species. For Pyrrhula pyrrhula polyomavirus 1, two genotypes were found that associated with the family of the finches, Estrildidae or Fringillidae.

Characterization of non-tuberculous mycobacterium from humans and water in an Agropastoral area in Zambia.

BACKGROUND: The non-tuberculous mycobacteria include those mycobacterium species that are not members of the Mycobacterium tuberculosis complex, the causative agent of pulmonary tuberculosis and Mycobacterium leprae. In Zambia, Non-tuberculous Mycobacteria are gaining recognition as pathogens of public health significance. However, there is scanty information on the isolation and speciation of these organisms for better patient management, consequently reducing the burden of these infections. Given the above information, the thrust of this study was to isolate and characterize NTM from humans and water in Namwala district of Zambia. METHOD: This was a cross-sectional study were 153 individuals with suspected TB were sampled from four health facilities in Namwala district, sputum samples were also collected. Additionally, 149 water samples were collected from different water drinking sources such as Tap water, Borehole water, rivers, wells and streams. Standard TB culture methods were employed to isolate Non-tuberculous Mycobacteria and later 16S-23S internal transcribed spacer region Sequencing was employed to characterize NTM. RESULTS: Seven (7, 4.6%) NTM species were identified from humans with M. arupense (3, 42.9%) being the most common organism, while twenty three (23, 15.4%) NTM were identified from water with the common species being Mycobacterium gordonae (5, 21.7%). Mycobacterium avium and Mycobacterium fortuitum were both identified from human and water samples. CONCLUSION: This study has shown the isolation of NTM species from humans and water. The isolation of NTM from drinking water sources could signify a public health risk to humans.

Small-Cell Lung Cancer Comorbid with Pulmonary Mycobacterium avium Infection: A Case Report.

BACKGROUND: Small-cell lung cancer (SCLC) rarely coexists with pulmonary Mycobacterium avium intracellular complex (MAC) infection. The key drug for SCLC treatment is etoposide, which is metabolized by cytochrome P-450 (CYP) 3A4. Meanwhile, the key drugs for pulmonary MAC infection are clarithromycin (CAM) and rifampicin (RFP), and their metabolism influences CYP3A4. Therefore, treatment of concurrent SCLC and pulmonary MAC infection is difficult, and to the best of our knowledge, no report of treatments for concurrent SCLC and pulmonary MAC infection has been published. Patient Concerns and Diagnoses: A 65-year-old man presented to our hospital with abnormal findings of chest computed tomography: (1) a hilar region nodule in the left lung and mediastinal lymphadenopathy and (2) a thick-walled cavity lesion in the right upper lobe of the lung. After further examinations, the former lesions were diagnosed as SCLC, cT4N3M0, stage IIIC and the latter as pulmonary MAC infection, fibrocavitary disease. INTERVENTIONS AND OUTCOMES: Concurrent treatment was conducted with discontinuation of CAM and RFP before and after etoposide administration. Specifically, intravenous cisplatin and etoposide were administered on day 1 and days 1-3, respectively, and CAM, RFP, and ethambutol (EB) were administered orally on days 6-22 every 4 weeks. Concurrent radiotherapy was added to the drug administration on days 1-27 of the first cycle. The chemotherapy was continued for 4 cycles, followed by continuation of CAM and RFP administration. EB was discontinued because of optic nerve disorder. The treatments were conducted completely and safely, and both of the SCLC lesions and the MAC lesion were improved. CONCLUSIONS: Treatments for concurrent SCLC and pulmonary MAC infection may be successfully conducted with discontinuation of CAM and RFP before and after etoposide administration.

Differences in drug susceptibility pattern between Mycobacterium avium and Mycobacterium intracellulare isolated in respiratory specimens.

Mycobacterium avium complex (MAC) is the most common etiologic organisms of nontuberculous mycobacteria (NTM) lung disease. In this study, we aimed to retrospectively investigate the differences in drug susceptibility patterns of two major MAC species; Mycobacterium avium and Mycobacterium intracellulare. A total of 1883 major two MAC isolates (1060 M. avium and 823 M. intracellulare) from respiratory specimens were included in this study during the period 2011─2016. The minimum inhibitory concentrations (MICs) were determined by broth microdilution method and MIC50/MIC90 values were derived from MIC distribution. M. intracellulare had generally low susceptible rates than M. avium for almost all tested antimicrobials except ethambutol and amikacin. The susceptible rate to clarithromycin was >94% of the MAC without significant differences between the two species. The MIC50 values of ciprofloxacin, clarithromycin, linezolid, moxifloxacin, and rifampicin were higher in M. intracellulare than in M. avium, contrary to the results of ethambutol with a higher MIC50 in M. avium. In general, M. intracellulare showed a higher resistance rate and higher MIC50 values than M. avium. Differences between this study and previous reports suggest regional differences in drug susceptibility profile of MAC species.

Variation of bacterioplankton community along an urban river impacted by touristic city: With a focus on pathogen.

Bacterioplankton communities play a critical role in ecological processes in river systems, and shifts of their composition may impact microbial levels and raise public health concerns. The aim of this study was to comprehensively analyze the essential factors influencing bacterioplankton community, along with pathogen, and to estimate the health risk caused by the pathogens downstream of the Liushahe River, which is located in the famous touristic city Xishuangbanna. Results showed that wastewater treatment plants (WWTPs) and a subtropical recreational park impacted the bacterioplankton community and pathogen population, and potential pathogen identification demonstrated that 76 of 145 reference genera were present in the river. Moreover, the bacterioplankton community and pathogen were differently impacted by environmental gradients, and SRP, NO2 and pH were main factors influencing bacterioplankton community while pathogen population was highly correlated with temperature and turbidity. In addition, it is noted that the pathogen population was dominated by bacterioplankton community and this might because the capacity of resistance invasion pathogen was determined by of bacterioplankton community diversity. Therefore, bacterioplankton community diversity can be used to control and predict the amount of pathogens. Quantitative microbial risk assessment (QMRA) also revealed that the infection risks of Escherichia coli (E. coli), Mycobacterium avium (M. avium), and Pseudomonas aeruginosa (P. aeruginosa) during five recreational activities, especially water-based activities in the touristic city, were greater than that in natural areas and mostly exceeded the U.S. EPA risk limit for recreational activities. Our study offered the first insight into the potential relationship between the bacterioplankton community and bacterial pathogens within a touristic river.

Prevalence and risk factors of mycobacterial infections in farm and trade cattle in southwestern Nigeria.

We evaluated the prevalence of mycobacterial infections (i.e., Mycobacterium bovis and non-tuberculous mycobacteria [NTM]) and their associated risk factors among cattle herds and trade cattle in southwestern Nigeria. Through cross-sectional study design, cattle herds from three locations were screened using the single intradermal comparative cervical tuberculin test based on two diagnostic standards; more than 4 mm (˃ 4 mm) and more than 2 mm (˃ 2 mm) cut-off points. Abattoir study involved screening trade cattle for tuberculous lesions. Overall, 515 cattle from 45 herds were screened. Using > 4 mm, animal level and herd prevalence of 11.7 and 46.7% were recorded, respectively. Applying the ˃ 2 mm cut-off, animal level and herd prevalence increased to 31.1 and 60.0%, respectively. Significantly, using the ˃ 2 mm cut-off, cattle in medium size herds/extensive management system (OR = 1.6; 95% CI 1.1-2.5) and Sokoto Gudali (OR = 2.3; 95% CI 1.4-3.8) were more at risk of being positive reactors, while Rahaji (OR = 0.3; 95% CI 0.1-0.7) breeds of cattle and cows in the peri-urban area (OR = 0.4; 95% CI 0.2-0.9) were less at risk of being positive reactors. Again, M. avium reactor of 21.7% was observed. In the abattoir, 1797 cattle were examined with 126 lesions suggestive of tuberculosis (TB). Culture/molecular analyses confirmed 2.2% M. bovis and 0.9% NTM infections. Risk factors associated with bovine TB among trade cattle were sex (OR = 4.0; 95% CI 1.2-13.5) and age (OR = 0.3; 95% CI 0.1-0.9). We confirm 11.7% prevalence of mycobacterial infections among populations of cattle screened with breed and herd size being major risk factors.