Mycobacterial Contamination Research Articles

Seasonal Dynamics of the Genetic Diversity of Mycobacteria in the Waters of Some Lowlands in Buruli Ulcer Endemic Areas in Côte d’Ivoire

The aim of this study was to assess the seasonal dynamics of mycobacterial genes from aquatic ecosystems. To achieve this goal, two field trips were conducted in four towns endemic to Buruli ulcer in Côte d’Ivoire: Abidjan, Daloa, Tiassalé, and Yamoussoukro; one during the dry season and the other during the rainy season. Water was analyzed for the presence of the insertion sequence IS2404 using real-time PCR. Conventional PCR was then used to highlight MIRU/VNTR sequences. Following the analyses, six samples presented the MIRU 1 sequence during the dry season, with one copy found in three samples and two copies in another three. In contrast, during the rainy season, seven samples contained the MIRU 1 sequence, with two copies in one sample and three copies in two others. It is important to note that all samples were negative for the Locus 6 gene. This study highlights the significant impact of seasonal climatic conditions on the genetic composition of water samples and suggests a close correlation between genetic markers and mycobacterial contamination. These findings could have important public health and water resource management implications, as they provide additional information to understanding the risks associated with water contamination based on seasons. This seasonal approach to studying genetic markers in water samples opens new avenues for further research aimed at deepening our understanding of the dynamics of microbiological contaminants caused by mycobacteria in aquatic ecosystems.

Building size and disinfectant type influence the detection and concentration of Mycobacterium spp. in hot water plumbing

The number of nontuberculous mycobacteria (NTM) lung disease cases is increasing in the United States (US). This respiratory disease is primarily caused by three NTM species: Mycobacterium avium, M. intracellulare, and M. abscessus. Since disease transmission could occur through water aerosolization, this study investigated these three species' occurrence (sporadic and persistent) in hot water samples collected from residences (n = 70) and office buildings (n = 30) across the US. A longitudinal survey design was used. Three quantitative Polymerase Chain Reaction (qPCR) assays were used to measure the mycobacterial species in the water samples. Additionally, the water's disinfectant residual was measured. A structure's age and square footage were evaluated to predict mycobacterial contamination. Also, the seasonal occurrence of each species was assessed by structure type. Residences had a 43 % (30/70), and office buildings had a 77 % (23/30) detection frequency of one or more Mycobacterium spp. in their hot water. The age of the structure influenced M. intracellulare detection frequency but not M. avium and M. abscessus. The structure's square footage affected M. avium and M. intracellulare detection frequency but not M. abscessus. In chlorinated water, M. intracellulare was detected 1.4× more often in office buildings' hot water than in chloraminated water. In chloraminated water, the Mycobacterium spp. were detected 2–2.5× more often in residences, while M. avium and M. abscessus were detected 1.5–2.3× more often in office buildings, compared to chlorinated water. Each Mycobacterium spp. had a different trend associated with the type of structure and disinfectant. Further research is needed to better understand NTM occurrence in the built environment to improve public health.

Mycobacterial contamination in tap and shower waters in Thailand.

Waterborne disease is increasingly becoming associated with opportunistic premise plumbing pathogens (OPPPs), which can resist residual chlorination, regrow throughout drinking water distribution systems, and colonize premise plumbing. Nontuberculous mycobacteria (NTM) include clinically important species and exert a high burden on healthcare systems. We briefly report a qPCR-based survey of Mycobacterium spp. numbers in tap, POU-treated, and shower waters from Bangkok, Thailand. Non-stagnant tap waters and non-stagnant shower waters had mean numbers of 1.3×103 and 2.4×103 copies/mL, respectively. Water stagnation resulted in mean numbers higher by up to 1.0 log. The lowest number, 25 copies/mL, was obtained from a POU-treated sample, while the highest number, 2.0×104 copies/mL, came from a stagnant tap. Comparing with international data, mean numbers in this study were greater than those in nine out of 11 (82%) comparable studies, and the maximum numbers in this study were also high. Our samples of Bangkok waters exhibited relatively high Mycobacterium spp. numbers, suggesting the need for appropriate POU treatment systems where NTM infection is a health concern. This survey data can be used to set inactivation performance targets in POU water disinfection system design and may also lead to quantitative microbial risk assessment (QMRA) studies.

Proceedings of the 2019 Viral Clearance Symposium, Session 7: Cell Banks and U.S. Pharmacopeia.

Adventitious contamination of a manufacturing process is a major concern for biopharmaceutical manufacturers. This session focused on rapid detection methods for adventitious agents and mitigation methods for upstream media and feeds. In the first session, it was shown that next-generation sequencing (NGS) can be a good rapid alternative to existing methods used to detect adventitious virus contamination. The second session showed that upstream virus barrier filters can robustly remove virus from media and feeds and could be a good alternative to high-temperature short time (HTST) aimed at facility contamination risk mitigation. In the third session, testing for Mycobacterium species was requested by the Chinese health authority for cell banks. In this case, the risk of mycobacterial contamination was minimal for well-characterized cell banks, and robust downstream processes are in place to remove any potential adventitious contaminants such as viruses and bacteria; therefore, it was not needed. In the final session, a review of rapid testing methods for viral detection was discussed as well as the possibility of using these technologies to replace existing methods.

Nosocomial Outbreak of Port-site Infection due to Atypical Mycobacteria following Laparoscopy: Suggested Infection Control Strategies

Introduction: Atypical mycobacteria can survive in conditions that make them hard to eradicate, despite using the standard decontamination procedures and protocols. Thus, errors in sterilisation techniques for laparoscopic instruments can be responsible for outbreaks caused by such bacteria and make it a problem mainly affecting developing countries including India. Aim: To investigate the outbreak of postlaparoscopic wound infection caused by atypical mycobacteria. Materials and Methods: An institution based cross-sectional study was conducted over a two-month period from January 2020 to February 2020. A total of 14 patients presented with postlaparoscopic surgical site wound infections were evaluated with Ziehl-Neelsen (ZN) staining and pus culture on Lowenstein Jensen (LJ) medium and subsequently treated with appropriate antibiotics. For further investigation of the outbreak, environmental samples were collected and isolation rates (percentage) of atypical mycobacteria from these samples were analysed. Results: All the patients included in the study were diagnosed with postlaparoscopic surgical site wound infections caused by atypical mycobacteria. Infection control investigation of the Operation Theatres (OTs) revealed multiple sources of atypical mycobacterial contamination viz., laparoscopic surgical instruments, used disinfectant (gluteraldehyde disinfectant solution) and tap aerators. Conclusion: Negative routine bacterial culture report of samples collected from port-sites should be further investigated for other aetiology e.g., atypical mycobacteria which do not grow on routine bacterial culture. Since high indices of suspicion followed by timely and efficient management of patients with postlaparoscopic surgical site infection are of critical importance.

Screening Novel Agent Combinations to Expedite CTCL Therapeutic Development

Screening Novel Agent Combinations to Expedite CTCL Therapeutic Development

Cutaneous T-Cell Lymphoma (CTCL) Cell Line-Derived Extracellular Vesicles Contain HERV-W-Encoded Fusogenic Syncytin-1

Cutaneous T-Cell Lymphoma (CTCL) Cell Line-Derived Extracellular Vesicles Contain HERV-W-Encoded Fusogenic Syncytin-1

Mycobacterial contamination of heater cooler units used in ECMO is not aerosolised into the environment: a single center experience

Mycobacterial contamination of heater cooler units used in ECMO is not aerosolised into the environment: a single center experience

3-5 気管支鏡の抗酸菌汚染対策( 第29回日本呼吸器内視鏡学会総会)

3-5 気管支鏡の抗酸菌汚染対策( 第29回日本呼吸器内視鏡学会総会)

Mycobacterial contamination of bronchoscopes: Challenges and possible solutions in low resource settings

The use of bronchoscopes has increased in tuberculosis (TB) diagnostics to circumvent the diagnostic challenges that are associated with low sputum volume and smear-negative TB. In healthcare facilities situated in low income countries that have a high burden of TB, adequate decontamination of bronchoscopes is a challenge and often overlooked to save on time and costs. This amplifies the risk of outbreaks and pseudo-outbreaks due to Mycobacterium tuberculosis and nontuberculosis mycobacteria. In this minireview, we review published literature of contaminated bronchoscopes causing pseudo-outbreaks of M. tuberculosis and nontuberculosis mycobacteria in an effort to determine common sources, and possible mitigation strategies in low-resource settings.

Face mask sampling for the detection of Mycobacterium tuberculosis in expelled aerosols.

BackgroundAlthough tuberculosis is transmitted by the airborne route, direct information on the natural output of bacilli into air by source cases is very limited. We sought to address this through sampling of expelled aerosols in face masks that were subsequently analyzed for mycobacterial contamination.MethodsIn series 1, 17 smear microscopy positive patients wore standard surgical face masks once or twice for periods between 10 minutes and 5 hours; mycobacterial contamination was detected using a bacteriophage assay. In series 2, 19 patients with suspected tuberculosis were studied in Leicester UK and 10 patients with at least one positive smear were studied in The Gambia. These subjects wore one FFP30 mask modified to contain a gelatin filter for one hour; this was subsequently analyzed by the Xpert MTB/RIF system.ResultsIn series 1, the bacteriophage assay detected live mycobacteria in 11/17 patients with wearing times between 10 and 120 minutes. Variation was seen in mask positivity and the level of contamination detected in multiple samples from the same patient. Two patients had non-tuberculous mycobacterial infections. In series 2, 13/20 patients with pulmonary tuberculosis produced positive masks and 0/9 patients with extrapulmonary or non-tuberculous diagnoses were mask positive. Overall, 65% of patients with confirmed pulmonary mycobacterial infection gave positive masks and this included 3/6 patients who received diagnostic bronchoalveolar lavages.ConclusionMask sampling provides a simple means of assessing mycobacterial output in non-sputum expectorant. The approach shows potential for application to the study of airborne transmission and to diagnosis.

Potentiation of high hydrostatic pressure inactivation of Mycobacterium by combination with physical and chemical conditions

Mycobacterium abscessus is an important hospital-acquired pathogen involved in infections associated with medical, surgical, and biopharmaceutical materials. In this work, we investigated the pressure-induced inactivation of two strains [2544 and American Type Culture Collection (ATCC) 19977] of M. abscessus in combination with different temperatures and pH conditions. For strain 2544, exposure to 250MPa for 90min did not significantly inactivate the bacteria at 20°C, whereas at -15°C, there was complete inactivation. Exposure to 250MPa at ≥60°C caused rapid inactivation, with no viable bacteria after 45min. With 45min of exposure, there were no viable bacteria at any temperature when a higher pressure (350MPa) was used. Extremes of pH (4 or 9) also markedly enhanced the pressure-induced inactivation of bacteria at 250MPa, with complete inactivation after 45min. In comparison, exposure of this strain to the disinfecting agent glutaraldehyde (0.5%) resulted in total inactivation within 5min. Strain 19977 was more sensitive to high pressure but less sensitive to glutaraldehyde than strain 2544. These results indicate that high hydrostatic pressure in combination with other physical parameters may be useful in reducing the mycobacterial contamination of medical materials and pharmaceuticals that are sensitive to autoclaving.

Evaluation of Hemostatic Field Dressing for Bacteria, Mycobacteria, or Fungus Contamination

Infectious complications have a major impact on wounded warriors. Pathogens causing infections include multidrug-resistant bacteria, fungi, and mycobacteria. The potential sources for these pathogens include nosocomial transmission, the environment (e.g., dirt), or the patients (skin flora) themselves. The purpose of this pilot study was to explore the possibility that hemostatic field dressings might act as an inoculation source of pathogens into wounds. To accomplish this, hemostatic field dressings were assessed for the presence of bacterial, fungal, or mycobacterial contamination. We evaluated two samples of QuikClot Combat Gauze and two samples of CELOX Gauze subjected to normal stresses associated with storage after receipt from the manufacturer. We then evaluated 16 samples of QuikClot Combat Gauze that were collected from personnel deployed in Afghanistan and had undergone routine mechanical stress. Samples underwent screening with Trypticase Soy Broth, blood agar plates, MacConkey agar plates, CHROMagar Staphylococcus aureus plates, chocolate agar plates, Potato Flake agar, Lowenstein-Jensen media, and Middlebrook 7H11 media. No bacteria, fungi, or mycobacteria were recovered from the dressings. It does not appear that hemostatic field dressings are contaminated, even after subjected to field conditions. Further research is needed to identify inoculation sources of fungi and mycobacteria, which cause infections.

The effect of kaolin feeding on efficiency, health status and course of diarrhoeal infections caused by enterotoxigenic Escherichia coli strains in weaned piglets

The purpose of the present study was to assess the effect of kaolin feeding on health status, body weight gain (BWG), course of diarrhoeal infections caused by enterotoxigenic strains of <i>Escherichia coli</i> (ETEC) and the level of mycobacterial contamination in weaned piglets. The testing was performed in two experiments involving 40 weaned piglets at the age of 28 days. In the infection-free experiment, piglets were fed a diet without (C0) or with 1% content of kaolin (K0) for 20 days. Subsequently, all of them were fed the same diet without kaolin supplementation for 39 days. Identical diets were fed during the infection experiment, and moreover, both groups (CI and KI) were orally infected with ETEC (O141:F18ac, STa+) on Day 1 of experiment. The short-term feeding of kaolin to weaned piglets had a significant positive effect on their BWG. During the period of feeding the kaolin-containing diets, BWG in C0 and K0 were 0.20 and 0.29 kg, respectively (<i>P</i> < 0.05), and in CI and KI 0.13 and 0.19 kg, respectively (<i>P</i> < 0.05). There was no evidence of side effects to their health, neither was there any change in biochemical and haematological profiles. In the infection experiment, a protective effect of kaolin on the course of ETEC infection was evident. Colonization and shedding of ETEC by piglets fed the kaolin diet were milder and had a shorter duration in comparison with control piglets. The culture examination of pure kaolin and kaolin containing diets for mycobacteria were negative. Potentially pathogenic mycobacteria occurring in the environment were isolated from faeces and tissues of pigs. According to these results, supplementation of diets with 1% kaolin to prevent diarrhoea in piglets and to support their growth in the critical post-weaning period could be recommended.

Mycobacterium avium–intracellulare contamination of mammalian cell cultures

Mycobacterium avium contamination has been described as a putative contaminant of nonphagocytic mammalian cells. Screening of numerous cultured nonphagocytic mammalian cell lines revealed the presence of intracellular bacteria that were identified as M. avium-intracellulare. An extensive and critical analysis of the origin of infection, of cure protocols, and of biological manifestations in M. avium-infected cells is presented. As no tremendous visible alteration of turbidity or pH of cell culture media, and no morphological change occurred in most M. avium-infected cell cultures, detection of an infection by these bacteria is rather difficult. Recommendations are given for treatment of irreplaceable cultures and prevention of mycobacterial contamination in a tissue culture facility.

American College of Chest Physicians and American Association for Bronchology Consensus Statement: Prevention of Flexible Bronchoscopy-Associated Infection

American College of Chest Physicians and American Association for Bronchology Consensus Statement: Prevention of Flexible Bronchoscopy-Associated Infection

Peat as a feed supplement for animals: a literature review

Peat is an easily available natural material and a source of biologically active substances widely used, not only in agriculture but in human and animal medicine as well. In recent years, interest in the use of peat as a feed supplement has increased, particularly due to its capability to prevent enteric diseases and to stimulate growth in piglets and pigs. The purpose of this review was to compare the advantages and risks associated with the use of peat for animal nutrition based on the literature available. Beneficial effects of various peat preparations on digestion, growth and the immune systems of animals as well as the absorbent and detoxifying capabilities are associated with the high content of favourable humic substances. One disadvantage of using peat preparations is the considerable diversity of the various types of peat caused by different biological, chemical and geological conditions during formation. Biological activity of various peat preparations is associated not only with fluctuations in the chemical compositions, but also with different application techniques. Based on the existing studies, it is unclear which application technique is most effective for respective animal species. Further studies should be conducted to elucidate the problem, with the inclusion of farm animals. One potential risk of peat feeding is the possibility of primary or secondary mycobacterial contamination. As long as feed rations are supplemented with peat preparations, it is essential to minimise the potential contamination risk during mining, processing and storage.

Longitudinal study of the spread of ovine Johne's disease in a sheep flock in southeastern New South Wales

The aim of this study was to apply whole flock testing over time to determine the prevalence, distribution and spread of infection in a recently infected flock, with a view to planning intervention strategies for disease control. Serology, pooled faecal culture (PFC) and histology were used to determine the distribution and persistence of infection in a sheep flock in south east New South Wales between 1997 and 2002. Partial flock testing was done up to June 2000, after which annual whole flock testing, using PFC was performed. Faecal shedding of M a paratuberculosis was not detected in home-bred sheep until 7 years after the introduction of infected sheep in 1993. For at least 7 years there was clustering of infection and shedding within two age groups only. The infected groups appeared to have been exposed to infection (mycobacterial contamination) at an early age (<12 months) and commenced shedding at 5 years of age or older. Groups that were exposed to contamination as adults did not shed detectable amounts of M a paratuberculosis during the study period. Clustering of detectable infection in age groups of sheep that were exposed as lambs was a feature on this farm, providing indirect evidence of finite duration of survival of M a paratuberculosis on pasture and the influence of age on the susceptibility of sheep to develop detectable M a paratuberculosis infection. Spread of infection occurred very slowly and was probably related to the long incubation period (exposure to shedding interval) of 5 years observed on this farm. The findings suggest that partial flock culling, selective grazing management and vaccination could lead to a reduction in mycobacterial contamination on farm to a level at which patent infection no longer occurs. Better understanding of disease spread within flocks over time through flock profiling using PFC will help in devising surveillance strategies (including testing protocols for market assurance testing) to detect infected flocks where there has been clustering and slow spread of infection.

Mycobacteria isolated from the environment of pig farms in the Czech Republic during the years 1996 to 2002

Sources of mycobacterial infections in 50 pig herds in the Czech Republicwere investigated during the years 1996 to 2002. A total of 2 412 samples from the external environment (feeds, bedding materials, drinking water, biofilms on drinkers, scrapings from the walls, floors and pen barriers, dust, spider webs, peat, kaolin, faeces, organs of rodents, and birds, etc.) were examined. After staining by the Ziehl-Neelsen technique, acid-fast rods were detected in 95 (3.9%) samples by direct microscopic examination and mycobacteria were cultured from 575 (23.8%) samples. From Mycobacterium avium complex (MAC), M. avium subsp. hominissuis (genotype IS901-, IS1245+) of serotypes 4, 6, 8, and 9 (272; 47.0% isolates), M. a. avium (genotype IS901+, IS1245+) of serotype 2 (13; 2.2% isolates) and M. intracellulare (genotype IS901-, IS1245-) of different serotypes (2; 0.3% isolates) were detected most frequently. Other isolates from among 14 other mycobacterial species ranked as follows: 64 M. gordonae, 47 M. fortuitum, 17 M. chelonae, 14 M. flavescens, 11 M. terrae, seven M. phlei, seven M. scrofulaceum, three M. diernhoferi, three M triviale, three M. smegmatis, two M. xenopi, one M. szulgai, one M. gastri, and one M. ulcerans. The remaining 111 isolates of unidentified species did not contain specific sequences IS901 and IS1245 characteristic for the pathogenic members of MAC (M. a. avium and M. a. hominis&amp;shy;suis). Peat, drinking water, biofilms on drinkers, bedding materials, feeds, free living birds, kaolin and charcoal were identified as potential sources of mycobacterial infections for pigs. Peat given to piglets as a feed supplement was the most important source of mycobacteria (65.1% positive of 327 examined samples); 81.2% of them were positive for M. a. hominissuis of serotypes 4, 6, 8, and 9. By contrast, mycobacteria of other species (M. gordonae, M. fortuitum, M. chelonae, M. flavescens, etc.) were the main isolates obtained from drinking water and biofilms on drinkers for pigs. By culture examination, the detection rate was higher in the biofilm samples (36.4%) than in the samples of drinking water (29.6%). The third group of sites with detected high levels (26.4%) of mycobacterial contamination were various types of beddings of woody material. M. a. hominissuis of serotypes 6, 8, and 9 were the most frequent isolates from sawdust; M. a. avium serotype 2 was sporadically detected. Mycobacterial findings in other samples from the external environment (wall and floor scrapings, dust, soil from the runs, and invertebrates) gave an indication of the pressure of infection in the herds. High contamination levels in faecal samples (15.6%) and in scrapings (18.4%) from respective parts of pens and stables indicated exposure of pigs to mycobacteria. In those materials, isolation of M. a. hominissuis of serotypes 4, 6, 8, and 9 prevailed. Mycobacteria were also detected in 7.9% of 430 samples of various invertebrate species. Various mycobacterial species were identified in the larvae and puparia of Eristalis tenax and Musca spp. and in imagoes of Drosophila spp., Musca spp., family Scatophagidae, Stomoxys calcitrans, E. tenax, and in earthworms. All of the constituents of the external environment that are potential sources of mycobacterial infections should be considered during implementation of preventative measures and the control of mycobacterial infections in pig herds.

An outbreak of Mycobacterium chelonae infection following liposuction.

Among 82 patients who underwent liposuction performed by a single practitioner in a 6-month period, 34 (41%) developed cutaneous abscesses. An organism identified as Mycobacterium chelonae by polymerase chain reaction restriction-enzyme analysis was recovered from cultures of samples from 12 of those patients. DNA large restriction-fragment pattern analysis by pulsed-field gel electrophoresis demonstrated that a strain of M. chelonae recovered from biofilm in the piped-water system in one of the physician's offices differed by only 2 restriction fragments from the 12 patient isolates, which differed from each other by 0 or 1 restriction fragment. A detailed retrospective cohort study that included interviews with former employees and statistical analysis of risk factors indicated that inadequate sterilization and rinsing of surgical equipment with tap water were likely sources of mycobacterial contamination. This is the first reported outbreak of nosocomial infection due to M. chelonae in which a source has been identified and the first to occur in association with liposuction in patients in the United States.