Influence of the Smoking and Spitting Behaviors in Public Smoking Areas on the Microbial Contamination and Spread

Objectives : The purpose of this study was to investigate the effect of spitting behavior on microbial public health in smoking areas. Through this investigation, bacterial concentration and spread of bacteria from the smoking areas were evaluated for the prospective public health and environment.Methods : The number of spitting and the spitting location in the smoking areas were measured visually by observers. For the microbial analysis, filter papers (5 × 5 cm) as sample collectors had been attached to the surface of the smoking areas for a given time. Using the collected filter paper, ATP bioluminescence measurement (RLU), colony forming unit (CFU) were measured. For the estimation of spitting behaviors in the smoking area on the spread microorganisms, saliva containing filters were selected from the areas, and fluorescent powder (0.01 g/cm2) was added to the papers. After 4 hours, the papers around the smoking areas were collected and the fluorescence activity was measured.Results and Discussion : The results showed that there was a clear relationship between the spitting behavior and the microbial activity in the smoking areas. In the case of sampling area A, the highest number of spitting was observed at the lunch hour (102 ± 16 times), and the RLU from the sample collected near the smoking area showed about 5,139 ± 1,267 RLU. When the RLU around the smoking area was measured, the lowest values were found at distance of 11 and 17 m from the cigarette bin (1,329 ± 148 and 1,204 ± 203 RLU), and it was confirmed that smoking and spitting did not occur at this sampling points. In the case of sampling area B, the highest number of spitting (45 ± 6 times) was observed at evening hour, and the RLU from the sample collected near the smoking area showed about 5,274 ± 1,297 RLU. The lowest value was in the sampling area B shown at 11 and 18 m (1,181 ± 243 RLU and 1,148 ± 168 RLU) from the cigarette bin, and it was also confirmed that smoking and spitting did not occur at this sampling points. The results indicate that the spitting during the smoking induced the increases of the microbial contamination of the public environment. The fluorescence powder diffusion analysis indicated that the saliva on the ground surface would enhance the spread of the microorganisms from the smoking area.Conclusions : Spitting in smoking areas can pose a high risk of microbial infection for smokers and non-smokers in smoking areas. Thus extensive and systematic attention related to the smoking manner must be paid to protect our public health.

The ATP bioluminescence assay: a new application and optimization for viability testing in the parasitic nematode Haemonchus contortus

The parasitic gastrointestinal nematode Haemonchus contortus causes serious economic losses to agriculture due to infection and disease in small ruminant livestock. The development of new therapies requires appropriate viability testing, with methods nowadays relying on larval motility or development using procedures that involve microscopy. None of the existing biochemical methods, however, are performed in adults, the target stage of the anthelmintic compounds. Here we present a new test for the viability of H. contortus adults and exsheathed third-stage larvae which is based on a bioluminescent assay of ATP content normalized to total protein concentration measured using bicinchoninic acid. All the procedure steps were optimized to achieve maximal sensitivity and robustness. This novel method can be used as a complementary assay for the phenotypic screening of new compounds with potential antinematode activity in exsheathed third-stage larvae and in adult males. Additionally, it might be used for the detection of drug-resistant isolates.

ATP Bioluminescence for Rapid and Selective Detection of Bacteria and Yeasts in Wine

Microbial contamination may represent a loss of money for wine producers as several defects can arise due to a microorganism’s growth during storage. The aim of this study was to implement a bioluminescence assay protocol to rapidly and simultaneously detect bacteria and yeasts in wines. Different wines samples were deliberately contaminated with bacteria and yeasts at different concentrations and filtered through two serial filters with decreasing mesh to separate bacteria and yeasts. These were resuscitated over 24 h on selective liquid media and analyzed by bioluminescence assay. ATP measurements discriminated the presence of yeasts and bacteria in artificially contaminated wine samples down to 50 CFU/L of yeasts and 1000 CFU/L of bacteria. The developed protocol allowed to detect, rapidly (24 h) and simultaneously, bacteria and yeasts in different types of wines. This would be of great interest for industries, for which an early detection and discrimination of microbial contaminants would help in the decision-making process.

ATP Bioluminescence for Assessing the Efficacy of the Manual Cleaning Procedure during the Reprocessing of Reusable Surgical Instruments

Achieving sterilization by adopting proper practices is essential to ensure that surgical instruments do not transmit microorganisms to patients. As the effectiveness of sterilization mandates effective cleaning, it is necessary to verify the success of cleaning procedures. In this study, we used the adenosine triphosphate (ATP) bioluminescence method for assessing the efficacy of the manual cleaning procedure during the reprocessing of reusable surgical instruments. The ATP bioluminescence assay was performed on 140 surgical instruments of 12 different types, both before being cleaned (baseline) and after each of the cleaning procedures (i.e., decontamination, manual washing, drying, and visual inspection). For each instrument, two swabs were used as follows: one to sample the entire surface (test point 1) and the other to sample the most difficult part of the surface to clean (test point 2). Overall, for each type of instrument, there was a decrease in contamination ranging from 99.6 to >99.9% (log reduction from 2.40 to 3.76). Thus, in order to standardize the assessment of cleanliness, it may be useful to introduce the bioluminescence method into the daily routine or, at least, at regular time intervals as a complementary check combined with visual inspection. This would allow real-time verification of the achievement of an adequate level of cleanliness.

Perioral Aerosol Sequestration Suction Device Effectively Reduces Biological Cross-Contamination in Dental Procedures

Objective The infection risk during dental procedures is a common concern for dental professionals which has increased due to coronavirus (severe acute respiratory syndrome coronavirus 2) pandemic. The development of devices to specifically mitigate cross-contamination by droplet/splatter is crucial to stop infection transmission. The objective of this study is to assess the effectiveness of a perioral suction device (Oral BioFilter, OBF) to reduce biological contamination spread during dental procedures. Materials and Methods Forty patients were randomized 1:1 to a standard professional dental hygiene treatment with OBF and without. Adenosine triphosphate (ATP) bioluminescence assay was used to evaluate the spread of potential contaminants. The total number of relative light units (RLU) from key dental operatory locations: operator’s face-shield, back of the surgical operator’s-gloves, patient’s safety-goggles, and instrumental table were measured. Percentage contamination reductions between control and OBF were compared. Statistical Analysis Primary outcome, total RLU, was analyzed by comparing the means of logged data, using a two-sided two-sample t-test. Secondary outcomes as RLU of logged data for the different locations were analyzed in the same way. Proportion of patients from whom different locations reported events (clean, acceptable, and failure) were analyzed by using Fisher’s exact test. Results For the whole dental environment, RLUs reduction (<150 units) achieved with OBF was 98.4% (97.4–99%). By dental operatory location the reduction in RLUs was from 99.6%, on the operator face-shield, to 83% on instrumental table. The control group reported a very high percentage of failures, (>300) being 100% on the surfaces closer to the patient’s mouth and decreasing to 70% on instrumental table. In contrast, the higher failure percentage in the OBF group was found on the patient’s goggles (40%), while the operator face-shield showed an absence of contamination. Conclusion OBF device has shown efficient reduction of biological aerosol cross-contamination during dental procedures as proved by ATP-bioluminescence assay. Nevertheless, for maximum safety, its use must be combined with standard protective gear such as goggles, face shield, and surgical gloves.