Mobile phones are hazardous microbial platforms warranting robust public health and biosecurity protocols.

Advancements in technology and communication have revolutionised the twenty-first century with the introduction of mobile phones and smartphones. These phones are known to be platforms harbouring microbes with recent research shedding light on the abundance and broad spectrum of organisms they harbour. Mobile phone use in the community and in professional sectors including health care settings is a potential source of microbial dissemination. To identify the diversity of microbial genetic signature present on mobile phones owned by hospital medical staff. Twenty-six mobile phones of health care staff were swabbed. DNA extraction for downstream next generation sequencing shotgun metagenomic microbial profiling was performed. Survey questionnaires were handed to the staff to collect information on mobile phone usage and users' behaviours. Each of the 26 mobile phones of this study was contaminated with microbes with the detection of antibiotic resistance and virulent factors. Taken together the sum of microbes and genes added together across all 26 mobile phones totalised 11,163 organisms (5714 bacteria, 675 fungi, 93 protists, 228 viruses, 4453 bacteriophages) and 2096 genes coding for antibiotic resistance and virulent factors. The survey of medical staff showed that 46% (12/26) of the participants used their mobile phones in the bathroom. Mobile phones are vectors of microbes and can contribute to microbial dissemination and nosocomial diseases worldwide. As fomites, mobile phones that are not decontaminated may pose serious risks for public health and biosecurity.

Viability of hospital pathogens on mobile phone.

INTRODUCTION: Clinical use of mobile phones have increased exponentially. Whilst evidence of contamination is documented, a key factor when determining potential risks of contamination, is establishing the duration the organism remains viable on the device. If pathogens are found to persist for extended duration, healthcare mobile phones may become fomites for cross departmental transmission. AIM: Determine the duration pathogenic bacteria, Acinetobacter baumannii, Escherichia coli, two Pseudomonas sp. Bacillus cereus, Enterococcus faecalis susceptible and resistant to vancomycin (VSE and VRE) Staphylococcus aureus susceptible and resistant to methicillin (MSSA and MRSA), and a coagulase negative Staphylococcus (CoNs) can remain viable on a mobile phone under controlled conditions. METHOD: Phones were inoculated with 106 - 107 of each bacterium. The duration of viability was measured from the point the inoculum had dried and CFUs retrieved at timed intervals over 28 days. RESULTS: The mean percentage of bacteria viable at each time point was significantly different (20mins, P = .004, 1 hour P = .014, 6 hours P = .006, 24 hours P = .004, 7 days P = .007, 14 days P = .003, 21 days P = .002- and 28 days P = .004). Gram-positive bacteria remained viable longer than gram-negative bacteria (P = .010). MSSA declined faster than MRSA within the first 6 hours (P = .036). CONCLUSIONS: The extended duration of bacterial viability indicates the ability for pathogens to persist on a device and remain viable long enough to be transmitted to new areas both within the hospital and out to the community. Mobile phone decontamination should occur in combination of hand hygiene.

Spatiotemporal evaporating droplet dynamics on fomites enhances long term bacterial pathogenesis.

Naturally drying bacterial droplets on inanimate surfaces representing fomites are the most consequential mode for transmitting infection through oro-fecal route. We provide a multiscale holistic approach to understand flow dynamics induced bacterial pattern formation on fomites leading to pathogenesis. The most virulent gut pathogen, Salmonella Typhimurium (STM), typically found in contaminated food and water, is used as model system in the current study. Evaporation-induced flow in sessile droplets facilitates the transport of STM, forming spatio-temporally varying bacterial deposition patterns based on droplet medium's nutrient scale. Mechanical and low moisture stress in the drying process reduced bacterial viability but interestingly induced hyper-proliferation of STM in macrophages, thereby augmenting virulence in fomites. In vivo studies of fomites in mice confirm that STM maintains enhanced virulence. This work demonstrates that stressed bacterial deposit morphologies formed over small timescale (minutes) on organic and inorganic surfaces, plays a significant role in enhancing fomite's pathogenesis over hours and days.

The correlation between ATP measurement and microbial contamination of inanimate surfaces.

BACKGROUND: The objective of this study was to determine the correlation between adenosine triphosphate (ATP) measurements and microbial contamination using a standardized method. Secondarily, analyzing reproducibility of ATP measurements and aerobic colony counts (ACC's) on the same surface. METHODS: ATP measurements and ACC's were conducted on 10 pre-defined fomites in a hospital and nursing home setting. Per fomite two ATP measurements and two agar plate measurements were conducted, each measurement was conducted on a 25 cm2 surface. Both measurements were compared and analyzed for correlation. RESULTS: In total 200 paired measurements were conducted, 200 ATP measurements and 200 ACC's. The mean of all ATP measurements tested on the same surface was calculated, as was for all 200 ACC's. There was a strong correlation between the mean of two ATP measurements on two different sites on the same fomite (R = 0.800, p < 0.001) as well as between two ACC measurements on the same fomite (R = 0.667, p < 0.001). A much weaker correlation was found between RLU values and ACC's (R = 0.244, p < 0.001). CONCLUSIONS: Reproducibility of ATP measurements and ACC's on the same fomite was good. However, the correlation between RLU values and ACC's on hospital surfaces was much lower. This may be explained by the wide variety of biological material that is measured with ATP, of which the bacterial load is only one of many components. ATP measurement can be used to give a quantifiable outcome for the rating of cleanliness in health care facilities, however the results cannot be translated into the level of microbial contamination.

Long-term antimicrobial effectiveness of a silver-impregnated foil on high-touch hospital surfaces in patient rooms.

BACKGROUND: The hospital environment has got more attention as evidence as source for bacterial transmission and subsequent hospital-acquired infection increased. Regular cleaning and disinfection have been proposed to lower the risk of infection, in particular for gram-positive bacteria. Auto-disinfecting surfaces would allow to decrease survival of pathogens, while limiting resource to achieve a safe environment in patient rooms. METHODS: A controlled trial to evaluate the antimicrobial effectiveness of a polyvinyl chloride foil containing an integrated silver-based agent (containing silver ions 2%) on high-touch surfaces in patient rooms. RESULTS: The overall log reduction of the mean values was 1.8 log10 CFU, the median 0.5 log10 CFU comparing bioburden of control vs antimicrobial foil (p < 0.01). Important pathogens were significantly less likely recovered from the foil, in particular enterococci. These effects were present even after 6 months of in-use. CONCLUSIONS: A foil containing an integrated silver-based agent applied to high-touch surfaces effectively results in lower recovery of important pathogens from such surfaces over a 6-month study period.

Child Mouthing of Soil and Contaminated Fomites and Unimproved Sanitation are Associated with Subsequent Poor Child Developmental Outcomes in Urban Bangladesh (CHoBI7 Program).

OBJECTIVE: To evaluate the relationship between mouthing of soil and living in unsanitary conditions and child cognitive development in urban Bangladesh. STUDY DESIGN: This prospective cohort study of 224 children under 5 years of age was conducted in urban Dhaka, Bangladesh. Developmental outcomes were assessed by communication, fine motor, gross motor, personal social, problem solving, and combined developmental scores measured by the Extended Ages and Stages Questionnaire (EASQ) at a 12-month follow-up visit. RESULTS: Children who had caregiver reports of puting soil in their mouths at the majority of surveillance visits had significantly lower combined EASQ Z scores (coefficient, -0.53; 95% CI, -0.83 to -0.22) at the 12-month follow-up visit. Children who had caregiver reports of putting visibly dirty objects in their mouths at the majority of visits had significantly lower combined EASQ Z scores (-0.50; 95% CI, -0.79 to -0.22). Children in households with unimproved sanitation had significantly lower combined EASQ Z scores (-0.63; 95% CI, -1.11 to -0.16). CONCLUSIONS: Children found to frequently put soil and visibly dirty objects in their mouths, and those who resided in households using unimproved sanitation, had lower subsequent cognitive developmental outcomes. These findings demonstrate the importance of interventions targeting child mouthing behaviors and sanitation infrastructure to decrease exposure to fecal pathogens and improve child cognitive developmental outcomes.

Occurrence and Transmission of blaNDM-Carrying Enterobacteriaceae from Geese and the Surrounding Environment on a Commercial Goose Farm.

We investigated the prevalence and transmission of NDM-producing Enterobacteriaceae in fecal samples of geese and environmental samples from a goose farm in southern China. The samples were cultivated on MacConkey agar plates supplemented with meropenem. Individual colonies were examined for blaNDM, and blaNDM-positive bacteria were characterized based on whole-genome sequencing (WGS) data from the Illumina and Oxford Nanopore Technologies (ONT) platforms. Of 117 samples analyzed, the carriage rates for New Delhi metallo-ß-lactamase (NDM)-positive Enterobacteriaceae were 47.1, 18, and 50% in geese, inanimate environments (sewage, soil, fodder, and dust), and mouse samples, respectively. Two variants (blaNDM-1 and blaNDM-5, in 4 and 40 isolates, respectively) were found among 44 blaNDM-positive Enterobacteriaceae; these variants belonged to eight species, and Escherichia coli was the most prevalent (50%). WGS analysis revealed that blaNDM coexisted with diverse antibiotic resistance genes (ARGs). Population structure analysis showed that most E. coli and Enterobacter sp. isolates were highly heterogeneous, while most Citrobacter sp. and P. stuartii isolates possessed extremely high genetic similarities. In addition, blaNDM-5-positive ST4358/ST48 E. coli isolates were found to be clonally spread between geese and the environment and were highly genetically similar to those reported from ducks, farm environments, and humans in China. Plasmid analysis indicated that IncX3 pHNYX644-1-like (n = 40) and untypeable pM2-1-like plasmids (n = 4) mediated blaNDM spread. pM2-1-like plasmids possessed diverse ARGs, including blaNDM-1, the arsenical and mercury resistance operons, and the maltose operon. Our findings revealed that the goose farm is a reservoir for NDM-positive Enterobacteriaceae The blaNDM contamination of wild mice and the novel pM2-1-like plasmid described here likely adds to the risk for dissemination of blaNDM and associated resistance genes.IMPORTANCE Carbapenem-resistant bacteria, in particular NDM-producing Enterobacteriaceae, have become a great threat to global public. These bacteria have been found not only in hospital and community environments but also among food animal production chains, which are recognized as reservoirs for NDM-producing Enterobacteriaceae However, the dissemination of NDM-producing bacteria in waterfowl farms has been less well explored. Our study demonstrates that the horizontal spread of blaNDM-carrying plasmids and the partial clonal spread of blaNDM-positive Enterobacteriaceae contribute to the widespread contamination of blaNDM in the goose farm ecosystem, including mice. Furthermore, we found a novel and transferable blaNDM-1-carrying multidrug resistance (MDR) plasmid that possessed multiple environmental adaptation-related genes. The outcomes of this study contribute to a better understanding of the prevalence and transmission of blaNDM-carrying Enterobacteriaceae among diverse niches in the farm ecosystem.

Particulate matter (PM2.5) as a potential SARS-CoV-2 carrier.

The rapid spread of the SARS-CoV-2 in the COVID-19 pandemic had raised questions on the route of transmission of this disease. Initial understanding was that transmission originated from respiratory droplets from an infected host to a susceptible host. However, indirect contact transmission of viable virus by fomites and through aerosols has also been suggested. Herein, we report the involvement of fine indoor air particulates with a diameter of ≤ 2.5 µm (PM2.5) as the virus's transport agent. PM2.5 was collected over four weeks during 48-h measurement intervals in four separate hospital wards containing different infected clusters in a teaching hospital in Kuala Lumpur, Malaysia. Our results indicated the highest SARS-CoV-2 RNA on PM2.5 in the ward with number of occupants. We suggest a link between the virus-laden PM2.5 and the ward's design. Patients' symptoms and numbers influence the number of airborne SARS-CoV-2 RNA with PM2.5 in an enclosed environment.

Child Mouthing of Feces and Fomites and Animal Contact are Associated with Diarrhea and Impaired Growth Among Young Children in the Democratic Republic of the Congo: A Prospective Cohort Study (REDUCE Program).

OBJECTIVE: To identify exposure pathways to fecal pathogens that are significant contributors to diarrheal diseases and impaired growth in young children, and to evaluate scalable interventions to reduce fecal contamination from these pathways. STUDY DESIGN: Reducing Enteropathy, Undernutrition, and Contamination in the Environment (REDUCE) was a prospective cohort study of 370 children <5 years of age was conducted in Walungu Territory, South Kivu, Democratic Republic of the Congo. Child mouthing behaviors were assessed through caregiver reports and 5-hour structured observations. Caregiver reports of child contact with animals and child diarrhea were also obtained. Anthropometric measurements were collected at baseline and at a 6-month follow-up. RESULTS: Children observed putting soil in their mouth during structured observation at baseline had a significantly higher odds of diarrhea at the 6-month follow-up (OR, 1.79; 95% CI, 1.04 to 3.07). Children observed mouthing feces during structured observation had a significant reduction in height-for-age z-score (HAZ) from baseline to the 6-month follow-up (ΔHAZ, -0.69; 95% CI, -1.34 to -0.04). A significant reduction in HAZ was also observed for children with caregiver reports of touching guinea pigs (-0.33; 95% CI, -0.58 to -0.08) and rabbits (-0.34; 95% CI, -0.64 to -0.04) and children with feces in their sleeping space during unannounced spot checks (-0.41; 95% CI, -0.74 to -0.09). CONCLUSIONS: These findings emphasize the urgent need for infant water, sanitation, and hygiene interventions targeting child mouthing behaviors, fecal contamination in child living spaces, and child contact with domestic animals to reduce exposure to fecal pathogens among susceptible populations.

Surface texture limits transfer of S. aureus, T4 bacteriophage, influenza B virus and human coronavirus.

Spread of pathogens on contaminated surfaces plays a key role in disease transmission. Surface technologies that control pathogen transfer can help control fomite transmission and are of great interest to public health. Here, we report a novel bead transfer method for evaluating fomite transmission in common laboratory settings. We show that this method meets several important criteria for quantitative test methods, including reasonableness, relevancy, resemblance, responsiveness, and repeatability, and therefore may be adaptable for standardization. In addition, this method can be applied to a wide variety of pathogens including bacteria, phage, and human viruses. Using the bead transfer method, we demonstrate that an engineered micropattern limits transfer of Staphylococcus aureus by 97.8% and T4 bacteriophage by 93.0% on silicone surfaces. Furthermore, the micropattern significantly reduces transfer of influenza B virus and human coronavirus on silicone and polypropylene surfaces. Our results highlight the potential of using surface texture as a valuable new strategy in combating infectious diseases.

Contaminación microbiana en estetoscopios utilizados por proveedores de salud / Microbial contamination in stethoscopes used by health care providers

Introducción: El estetoscopio se ha descrito como un fómite capaz de transmitir patemas de tipo infeccioso a los trabajadores de la salud Objetivo: Caracterizar la presencia de contaminación microbiana en estetoscopios utilizados por proveedores de salud. Métodos: Estudio transversal en 50 muestras microbiológicas obtenidas de estetoscopios pertenecientes a proveedores de salud que laboran en el Hospital Pediátrico Cerro, de junio-octubre de 2019. Se aplicó una encuesta para evaluar variables demográficas y epidemiológicas de sus titulares relacionadas con la aplicación de medidas descontaminantes. Se examinaron los resultados mediante el análisis porcentual y prueba de Ji-cuadrada para buscar asociación significativa (p≤0,05) con los hábitos higiénicos. Resultados: El 100 por ciento de los estetoscopios están contaminados. Los aislamientos más frecuentes fueron: Staphylococcus alba 40,3 por ciento, Staphylococcus aureus 32,6 por ciento y Klebsiella pneumoniae 3,8 por ciento. Las áreas de mayor contagio fueron las de misceláneas (44,2 por ciento) y de respiratorio (36,5 por ciento). El personal con notable contaminación en sus equipos fueron los alumnos (81,4 por ciento) y los especialistas (14,8 por ciento). Las causas que determinaron no practicar la desinfección en los alumnos fue la falta de enseñanza (45,4 por ciento); en los especialistas, la carencia de hábitos (33,3 por ciento) y la falta de desinfectante (66,3 por ciento). Las bacterias gramnegativas fueron sensibles en su mayoría a los aminoglucósidos y Staphylococcus aureus a la clindamicina, vancomicina, ciprofloxacino y cloranfenicol. Conclusiones: Existe alta frecuencia de contaminación en los estetoscopios utilizados por los proveedores de salud motivado por la falta de hábito de desinfección en médicos y su desconocimiento en alumnos(AU)

Introduction: Stethoscopes has been described as a fomite which is able to transmit infectious agents to health care workers. Objective: To describe the presence of microbial contamination in stethoscopes used by health care providers. Methods: Cross-sectional study in 50 microbiological samples obtained from stethoscopes belonging to health care providers whom worked in Cerro Pediatric Hospital from June to October, 2019. It was applied a survey to evaluate demographic and epidemiologic variables of the owners related with the implementation of disinfection measures. The results were examined through percentage analysis and the Ji-square test to look for significative relation (p≤0,05) with hygene habits. Results: 100 percent of the stethoscopes were contamined. The most frequent isolated agents were: Staphylococcus alba 40.3 percent, Staphylococcus aureus 32.6 percent and Klebsiella pneumoniae 3.8 percent. The hospital areas with more contagion were: Miscellany (44.2 percent) and Respiratory (36.5 percent). The personnel with more contamination in their equipments were: students (81.4 percent) and specialists (14.8 percent). The cause of not doing the disinfection processes in the students was the lack of knowledge (45.4 percent); and in the specialists was the lack of hygene habits and the lack of disinfectant solutions (66.3 percent). Negative Gran bacteria were mostly sensitive to aminoglycosides and Staphylococcus aureus to clindamycin, vancomycin, ciprofloxacin and cloramphenicol. Conclusions: There is high frequency of contamination in the stethoscopes used by health care providers, mainly motived by the lack of disinfection habits in physicians and lack of knowledge on it in the students(AU)

Methicillin Resistant Staphylococcus aureus and public fomites: a review.

Staphylococcus genus is a Gram-positive coccus normally associated with skin and mucous membranes of warm-blooded animals. It is part of the commensal human microflora, or found in animals, or contaminating surfaces in the community and hospital settings. Staphylococcus aureus is the most pathogenic species belonging to this genus, as it possesses a collection of virulence factors that are expressed solely to evade the immune system. The increase in the misuse of antimicrobial agents predisposed S. aureus to develop antibiotic resistance, including the resistance to methicillin which led to the emergence of Methicillin-Resistant S. aureus (MRSA). MRSA is considered one of the most dangerous nosocomial pathogens causing many hard to treat infections in hospitals and was named as Hospital Associated MRSA (HA-MRSA). Over the past 20-25 years, MRSA was isolated from community settings and thus Community Associated MRSA (CA-MRSA) has emerged. Inside hospitals, MRSA has been isolated from fomites in contact with patients, as well as staff's protective and personal items. This review highlights the worldwide prevalence of MRSA on fomites within the contexts of hospital and community settings.

Introduction to Transmission of Infection: Potential Agents Transmitted by Endoscopy.

Pathogen contamination of endoscopes depends on pathogen factors, surface factors, and environmental conditions. The most common pathogens associated with transmission and infections associated with gastrointestinal endoscope contamination are Klebsiella pneumoniae, Escherichia coli, and Pseudomonas aeruginosa. Biofilm production together with disruption to device surfaces play an outsized role in the risk of contamination. Sampling schemes are limited by these factors, and further developments are needed to improve the accuracy of sampling.

Duodenoscope as a Vector for Transmission.

Elevator-based endoscope-related infections from patient cross-contamination is a multifactorial problem related to device design, maintenance, and function, with additional risk incurred from a high-level disinfection process that lacks quality controls. This article reviews the historical context for these outbreaks, technical aspects of scope design contributing to this risk, and innovations in endoscope technology that have the potential to overcome these shortcomings. Also reviewed are interim solutions and the data that support use of some of these interventions. Still needed are a validated manufacturer-recommended schedule for routine duodenoscope and echoendoscope maintenance with reprocessing protocols that can be implemented in endoscopy units.

Molecular characterization of Staphylococcus aureus complex from fomites in Nigeria.

Fomites serve as a potential route for the transmission of pathogens including community-acquired methicillin-resistant Staphylococcus aureus to humans. Phylogenetic and taxonomic analyses have established the Staphylococcus aureus complex (S. aureus, S. argenteus and S. schweitzeri), however, phenotypic characteristics are insufficient in the delineation of these species. In this study, we describe the S. aureus complex from inanimate surfaces in Nigeria. Fomite samples in Obafemi Awolowo University were initially screened for S. aureus and species differentiation was determined by MALDI-TOF, PCR of the S. aureus specific thermonuclease and the nonribosomal peptide synthetase genes. Characterization of the isolates was based on antimicrobial susceptibility, spa typing, multilocus sequence typing and virulence gene detection (lukS/lukF-PV, chp, sak, scn). Whole-genome sequencing was done for selected isolates. Of the 239 fomites samples, 14  S. aureus and two S. schweitzeri isolates were identified including three MRSA. Genotyping classified the S. aureus isolates into ST8/CC8, ST30/CC30, ST15/ST5875/CC15, ST508/ST5876/CC45, ST121/CC121, ST152/CC152 and ST3961. All the isolates in CC30, CC121, and CC152 were lukS/lukF-PV positive. The MRSA (PVL+) were assigned with CC152. Phylogenetic analysis revealed that the S. schweitzeri isolates were closely related with those from fruit bats (Eidolon helvum) in Nigeria. The differentiation of S. aureus from S. schweitzeri was clearly achieved through MALDI-TOF and PCR. Fomites are not only a reservoir for S. aureus but also for S. schweitzeri that was so far recovered primarily in African wildlife.

Cross-contamination by disinfectant towelettes varies by product chemistry and strain.

BACKGROUND: Disinfectant products are used frequently on environmental surfaces (e.g. medical equipment, countertops, patient beds) and patient care equipment within healthcare facilities. The purpose of this study was to assess the risk of cross-contamination of Staphylococcus aureus and Pseudomonas aeruginosa during and after disinfection of predetermined surface areas with ready-to-use (RTU) pre-wetted disinfectant towelettes. METHODS: This study tested six disinfectant towelette products against S. aureus ATCC CRM-6538 and P. aeruginosa strain ATCC-15442 on Formica surfaces. Each disinfectant was evaluated on a hard nonporous surface and efficacy was measured every 0.5 m2 using a modified version of EPA MLB SOP-MB-33 to study the risk of cross-contamination. RESULTS: We found that all of the wipes used in this study transferred S. aureus and P. aeruginosa from an inoculated surface to previously uncontaminated surfaces. Disinfectant towelettes with certain chemistries also retained a high level of viable bacteria after disinfection of the surface area. The cross-contamination risk also varied by product chemistry and bacterial strain. CONCLUSION: Disinfectant wipes can cross-contaminate hard nonporous surfaces and retain viable bacterial cells post-disinfection, especially over larger surface areas. This highlights a need to further investigate the risk disinfectant wipes pose during and post-disinfection and guidance on maximum surface areas treated with a single towelette.

Role of pulsed-xenon ultraviolet light in reducing healthcare-associated infections: a systematic review and meta-analysis.

Pulsed-xenon-ultraviolet light (PX-UVL) is increasingly used as a supplemental disinfection method in healthcare settings. We undertook a systematic search of the literature through several databases and conducted a meta-analysis to evaluate the efficacy of PX-UVL in reducing healthcare-associated infections. Eleven studies were included in the systematic review and nine in the meta-analysis. Pooled analysis of seven studies with before-after data indicated a statistically significant reduction of Clostridium difficile infection (CDI) rates with the use of the PX-UVL (incidence rate ratio (IRR): 0.73, 95% CI 0.57-0.94, I2 = 72%, P = 0.01), and four studies reported a reduction of risk of methicillin-resistant Staphylococcus aureus (MRSA) infections (IRR: 0.79, 95% CI 0.64-0.98, I2 = 35%, P = 0.03). However, a further four trials found no significant reduction in vancomycin-resistant enterococci (VRE) infection rates (IRR: 0.80, 95% CI 0.63-1.01, I2 = 60%, P = 0.06). The results for CDI and MRSA proved unstable on sensitivity analysis. Meta-regression analysis did not demonstrate any influence of study duration or intervention duration on CDI rates. We conclude that the use of PX-UVL, in addition to standard disinfection protocols, may help to reduce the incidence of CDI and MRSA but not VRE infection rates. However, the quality of evidence is not high, with unstable results and wide confidence intervals, and further high-quality studies are required to supplement the current evidence.

Viability PCR shows that non-ocular surfaces could contribute to transmission of Chlamydia trachomatis infection in trachoma.

BACKGROUND: The presence of Chlamydia trachomatis (Ct) DNA at non-ocular sites suggests that these sites may represent plausible routes of Ct transmission in trachoma. However, qPCR cannot discriminate between DNA from viable and non-viable bacteria. Here we use a propodium monoazide based viability PCR to investigate how long Ct remains viable at non-ocular sites under laboratory-controlled conditions. METHODS: Cultured Ct stocks (strain A2497) were diluted to final concentrations of 1000, 100, 10 and 1 omcB copies/µL and applied to plastic, woven mat, cotton cloth and pig skin. Swabs were then systemically collected from each surface and tested for the presence Ct DNA using qPCR. If Ct DNA was recovered, Ct viability was assessed over time by spiking multiple areas of the same surface type with the same final concentrations. Swabs were collected from each surface at 0, 2, 4, 6, 8 and 24 hours after spiking. Viability PCR was used to determine Ct viability at each timepoint. RESULTS: We were able to detect Ct DNA on all surfaces except the woven mat. Total Ct DNA remained detectable and stable over 24 hours for all concentrations applied to plastic, pig skin and cotton cloth. The amount of viable Ct decreased over time. For plastic and skin surfaces, only those where concentrations of 100 or 1000 omcB copies/µL were applied still had viable loads detectable after 24 hours. Cotton cloth showed a more rapid decrease and only those where concentrations of 1000 omcB copies/µL were applied still had viable DNA detectable after 24 hours. CONCLUSION: Plastic, cotton cloth and skin may contribute to transmission of the Ct strains that cause trachoma, by acting as sites where reservoirs of bacteria are deposited and later collected and transferred mechanically into previously uninfected eyes.