Fluorescent study of wastewater and the effect of low quantity of disinfectant

In the last few years due to the COVID-19 pandemic the pollution with large quantities of medicaments, disinfectants and essential oils raised the importance of their detection in wastewater. The research of new techniques for diagnostics continues. Some promising methods for finding contaminators of different origin are based on the optic and spectral characteristics of the examined water. Those could be used in determining the exact pollutant. The spectroscopic examination could also be conducted real-time under in vivo conditions. In this research, we use fluorescence spectroscopy to investigate the purity of water probes from the discharge of the Iskar River near the treatment plant in Samokov (Bulgaria) and the influence of small amounts of disinfectants (ethanol). The results show that fluorescence can be used to determine the purity of water probes and little amounts of alcohol in wastewater.

Considering Covid-19 Treatments as Applied to Facility Seating: Developing a Methodology to Examine Adverse Surface Color Effects

During Covid-19, a facility management researcher/instructor team examined potential effects of various disinfectant treatments on the surface appearance of furniture currently located in their academic facility. Treatments (i.e., bleach wipes, alcohol wipes, disinfectant sprays and UltraViolet wands) are used by students, staff, faculty, visitors, facility managers and custodians in an effort to reduce spread of Corona. Further, EMist© with Vital Oxide treatments were regularly applied by University-contracted facility maintenance staff during study period. While procedures exist for measuring color change regarding light exposure and changes due to abrasion, no current published methods were found regarding surface color before and after Covid-19 intervention treatments. Researchers/instructors anticipate findings from study would inform facility management and other courses. They anticipate results would allow generalizability to hospitality and healthcare. Changes in surface color of upholstered furniture in facilities may be extremely negative regarding interior aesthetics, corporate image, and replacement costs. Therefore, it was determined there was a great need to study the effects of treatments and inform facility stakeholders. Researchers posited that Covid-19 intervention treatments may alter surface color of upholstered furniture over time. The purpose of the study was to develop methodology to examine color degradation that may be caused by agents used in common disinfecting practices. Three seating pieces (drafting chair, drafting stool, classroom chair) made of different materials were studied. Five treatments were applied to each furniture piece at regular intervals over an 8-week period. Researchers measured color before and after treatments. The procedures were photo-documented and videotaped to capture treatments in-process and to support future educational presentations. Preliminary findings revealed limited variability in color changes. Future research should consider other seating and room-finish materials, disinfectants and treatments, facility types, and timeframes.

Antiviral effect of oral antiseptic solutions commonly used in dentistry practice: A scoping review

Objective: The purpose of this scoping review is to show the evidence available in the literature and provide an overview of the antimicrobial-containing mouthwashes for reducing viral load in order to group the most up-to-date information and make it more accessible to dentists. Design(s): A structured electronic search in PubMed (Medline), LILACS, EMBASE and EBSCO without temporal restriction was performed. The studies were selected based on their title, and full reading following a pre-established order based on the inclusion and exclusion criteria. The included studies were those that analyzed the effect of viral load reduction by mouthwashes, primary studies, no reviews and in Spanish, English or Portuguese. Result(s): The search resulted in 1881 articles, at the end of the exclusion of duplicates and selection, 71 articles were included in this scoping review. The substances most commonly found were chlorhexidine (CHX), povidone-iodine (PVP-I), essential oils (EO), cetylpyridinium chloride (CPC), hydrogen peroxide (H2O2) and other substances (OTHERS). Conclusion(s): Of all the mouthwashes analyzed, the Essential oils, Cetylpyridinium Chloride and Povidone-iodine, showed antiviral potential against common viruses present in the oral cavity, with no significant side effects in short-term use, and are viable options for use as a pre-procedure in clinical routine against SARS-CoV-2 and other types of viruses. The other solutions need further studies to determine their effect and confirm their clinical use.Copyright © 2023

Quaternary ammonium disinfectants and antiseptics: tolerance, resistance and potential impact on antibiotic resistance.

BACKGROUND: Due to the substantial increase in the use of disinfectants containing quaternary ammonion compounds (QACs) in healthcare and community settings during the COVID-19 pandemic, there is increased concern that heavy use might cause bacteria to develop resistance to QACs or contribute to antibiotic resistance. The purpose of this review is to briefly discuss the mechanisms of QAC tolerance and resistance, laboratory-based evidence of tolerance and resistance, their occurrence in healthcare and other real-world settings, and the possible impact of QAC use on antibiotic resistance. METHODS: A literature search was conducted using the PubMed database. The search was limited to English language articles dealing with tolerance or resistance to QACs present in disinfectants or antiseptics, and potential impact on antibiotic resistance. The review covered the period from 2000 to mid-Jan 2023. RESULTS: Mechanisms of QAC tolerance or resistance include innate bacterial cell wall structure, changes in cell membrane structure and function, efflux pumps, biofilm formation, and QAC degradation. In vitro studies have helped elucidate how bacteria can develop tolerance or resistance to QACs and antibiotics. While relatively uncommon, multiple episodes of contaminated in-use disinfectants and antiseptics, which are often due to inappropriate use of products, have caused outbreaks of healthcare-associated infections. Several studies have identified a correlation between benzalkonium chloride (BAC) tolerance and clinically-defined antibiotic resistance. The occurrence of mobile genetic determinants carrying multiple genes that encode for QAC or antibiotic tolerance raises the concern that widespread QAC use might facilitate the emergence of antibiotic resistance. Despite some evidence from laboratory-based studies, there is insufficient evidence in real-world settings to conclude that frequent use of QAC disinfectants and antiseptics has promoted widespread emergence of antibiotic resistance. CONCLUSIONS: Laboratory studies have identified multiple mechanisms by which bacteria can develop tolerance or resistance to QACs and antibiotics. De novo development of tolerance or resistance in real-world settings is uncommon. Increased attention to proper use of disinfectants is needed to prevent contamination of QAC disinfectants. Additional research is needed to answer many questions and concerns related to use of QAC disinfectants and their potential impact on antibiotic resistance.

Antiviral effect of oral antiseptic solutions commonly used in dentistry practice: a scoping review

Objective The purpose of this scoping review is to show the evidence available in the literature and provide an overview of the antimicrobial-containing mouthwashes for reducing viral load in order to group the most up-to-date information and make it more accessible to dentists. Design A structured electronic search in PubMed (Medline), LILACS, EMBASE and EBSCO without temporal restriction was performed. The studies were selected based on their title, and full reading following a pre-established order based on the inclusion and exclusion criteria. The included studies were those that analyzed the effect of viral load reduction by mouthwashes, primary studies, no reviews and in Spanish, English or Portuguese. Results The search resulted in 1881 articles, at the end of the exclusion of duplicates and selection, 71 articles were included in this scoping review. The substances most commonly found were chlorhexidine (CHX), povidone-iodine (PVP-I), essential oils (EO), cetylpyridinium chloride (CPC), hydrogen peroxide (H2O2) and other substances (OTHERS). Conclusion Of all the mouthwashes analyzed, the Essential oils, Cetylpyridinium Chloride and Povidone-iodine, showed antiviral potential against common viruses present in the oral cavity, with no significant side effects in short-term use, and are viable options for use as a pre-procedure in clinical routine against SARS-CoV-2 and other types of viruses. The other solutions need further studies to determine their effect and confirm their clinical use.

The effect of disinfectants and antiseptics on co- and cross-selection of resistance to antibiotics in aquatic environments and wastewater treatment plants.

The outbreak of the SARS-CoV-2 pandemic led to increased use of disinfectants and antiseptics (DAs), resulting in higher concentrations of these compounds in wastewaters, wastewater treatment plant (WWTP) effluents and receiving water bodies. Their constant presence in water bodies may lead to development and acquisition of resistance against the DAs. In addition, they may also promote antibiotic resistance (AR) due to cross- and co-selection of AR among bacteria that are exposed to the DAs, which is a highly important issue with regards to human and environmental health. This review addresses this issue and provides an overview of DAs structure together with their modes of action against microorganisms. Relevant examples of the most effective treatment techniques to increase the DAs removal efficiency from wastewater are discussed. Moreover, insight on the resistance mechanisms to DAs and the mechanism of DAs enhancement of cross- and co-selection of ARs are presented. Furthermore, this review discusses the impact of DAs on resistance against antibiotics, the occurrence of DAs in aquatic systems, and DA removal mechanisms in WWTPs, which in principle serve as the final barrier before releasing these compounds into the receiving environment. By recognition of important research gaps, research needs to determine the impact of the majority of DAs in WWTPs and the consequences of their presence and spread of antibiotic resistance were identified.

Development of A Low End Arduino Based Automatic Disinfectant Sprayer for New Normal Classroom

- Covid-19 is an infectious disease that attacks the respiratory system caused by the coronavirus found in 2019. It has a deadly infection and rapid spread worldwide without exception in Indonesia. Then since the year, World Health Organization (WHO) has declared it a world pandemic. One way to prevent the spread of Covid-19, especially in the closed public area, is by spraying disinfectant to kill the virus. In this project, a low-end disinfectant sprayer has been built based on an Arduino system. The sprayer has been applied to a 10.3mx7.8m classroom with 30 units of the misting device. Performance test of the system shows that the sprayer can work accurately at the timetable to spray the classroom by consuming 58.31 W in operation and 19.80W in standby mode. The total hardware implementation cost is IDR 904,225 or less than USD 65, making affordability for implementing the system.

Evaluation of hand hygiene practices among patients visiting dental college of purvanchal region - A cross-sectional study

Background: Effective hand hygiene is one of the most cost-efficient means of preventing infectious diseases in the community. Studies conducted to assess the hand hygiene practices of the general population in India are relatively limited. The present study was conducted with the aim to assess hand hygiene practices among the participants visiting the outpatient department (OPD) of a dental institute in the Purvanchal region in India. Materials and Methods: This cross-sectional study was conducted on 880 participants visiting the OPD of a dental college in the Purvanchal region. The data were collected using a pretested questionnaire focusing on the hand hygiene practices of the participants. Statistical analysis was done using Chi-square test and the level of significance was set at 5%. Results: Results showed that 98.5% of the respondents used soap/antiseptic liquid soap or hand sanitizer. The frequency of handwashing increased with the improvement in socioeconomic status, with almost 70% of upper-class participants washing their hands daily 5-6 times or more (P = 0.001). A significant association was seen between education and extension of handwashing (P = 0.001). Conclusion: Majority of the population were using soap and water for handwashing which shows that people are aware that proper hand hygiene is necessary to prevent the spread of infectious diseases, especially COVID-19. However, more work is needed to educate people from lower socioeconomic status about good hand hygiene practices.

Antiseptic drugs and disinfectants with experience of the second year of COVID-19 pandemic-related side effects

This review covers publications during the period January 2021 to December 2021 on adverse reactions to antiseptic drugs and disinfectants. Specific agents discussed are alcohols (ethanol, isopropanol), aldehydes (formaldehyde), ethylene oxide, guanidines (chlorhexidine, polyhexamethylene guanidine, and polyhexamethylene biguanidine), benzalkonium compounds, triclosan, povidone-iodine, and sodium hypochlorite. No new data were identified for glutaraldehyde, cetrimide, tosylchloramide, triclocarban, and phenolic compounds. The use of antiseptic drugs and disinfectants has increased considerably since 2020 in various medical and occupational settings, in commerce and gastronomy, as well as in the home, due to their antiviral properties against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) during the still ongoing Coronavirus Disease 2019 (COVID-19) pandemic. Irritant effects on the respiratory system, the skin and eyes were the most common adverse reaction, while the widespread and occasionally excessive use led to increased reports of poisonings as well as of oral misuse of disinfectants, sometimes associated with serious outcomes such as death from methanol intoxication. Eye exposures in children caused by inadvertent exposures due to unsupervised dispensers in public spaces were pointed out as being specifically problematic. Side effects in the eye may also occur in the general population by improper and unprotected use of UV lamps. The need to improve the safe use of disinfectant devices was pointed out in general.

COVID-19 prevention education and awareness through community outreach

This is a brief account of a community project that the medical staff of an urban primary care institution carried out. The goal was to spread knowledge and raise awareness about COVID-19 prevention among the Ghanaian communities that are a part of the Manna Mission Hospital's catchment area in the Ledzokuku Municipality. It has been discovered that community-based health education has a larger effect on the prevention of newly emerging infectious diseases, resulting in a decrease in the occurrence of such diseases. The pandemic caused by COVID-19 is not an exception. Results of a community outreach effort carried out by employees of a Ghanaian urban primary care hospital were emphasised in this paper. Increased health education is required to raise community residents' understanding of COVID-19's impact on public health. This community outreach initiative has raised awareness of COVID-19 prevention and control, handwashing, and facemask use. Many patients who attended the hospital wore face masks, frequently washed their hands with soap and water while it was running, and frequently used alcohol-based hand sanitisers, all signs of increased awareness. To stop the spread of COVID-19 in their communities, the primary healthcare workforce has a crucial role to play.

Research progress on the application of antiseptics after mucosal exposure of SARS-CoV-2

The transmission routes of SARS-CoV-2 include droplet, air and contact transmission, but regardless of the transmission route, the virus must eventually be exposed through the oral, nasal and ocular mucous membranes to invade the human body. Guaranteeing the respiratory protection of front-line medical staff in the prevention and control of COVID-19 is one of the primary tasks of nosocomial infection management. According to "Technical Guidelines for Prevention and Control of COVID-19 in Healthcare Settings (3rd Edition)", oral/nasal cavity can be disinfected with hydrogen peroxide, iodophor, in the event of occupational respiratory exposure. But, at the moment, In the field of nosocomial management, compared with hand hygiene, "mucosal hygiene" is rarely mentioned, especially the treatment of respiratory mucosa after exposure to acute infectious respiratory pathogens, which is still blank in the domestic research. After a rapid literature review, it is found that some antiseptics have been widely used in clinical practices, such as gargling with bactericidal solution before the diagnosis and treatment procedure for dental patients under COVID-19 epidemic, nasal decolonization for patients undergoing elective surgery to prevent surgical site infection, and use of eye drops of antiseptics to prevent neonatal conjunctivitis. In view of the current lack of effective antiviral drugs for treatment of SARS-CoV-2, and the constantly emerging mutant strains can break through the immune barrier of human body, this paper recommends that medical personnel use antiseptics for emergency mucosal disinfection as an supporting measure for respiratory tract protection after accidental exposure to SARS-CoV-2 of oral, nasal and ocular mucosa.

Rutile-TiO2/PtO2 Glass Coatings Disinfects Aquatic Legionella pneumophila via Morphology Change and Endotoxin Degradation under LED Irradiation

Legionella pneumophila (L. pneumophila) is the causative agent of Legionnaires’ disease and Pontiac fever, collectively known as legionellosis. L. pneumophila infection occurs through inhalation of contaminated aerosols from water systems in workplaces and institutions. The development of disinfectants that can eliminate L. pneumophila in such water systems without evacuating people is needed to prevent the spread of L. pneumophila. Photocatalysts are attractive disinfectants that do not harm human health. In particular, the TiO2 photocatalyst kills L. pneumophila under various conditions, but its mode of action is unknown. Here, we confirmed the high performance of TiO2 photocatalyst containing PtO2 via the degradation of methylene blue (half-value period: 19.2 min) and bactericidal activity against Escherichia coli (half-value period: 15.1 min) in water. Using transmission electron microscopy, we demonstrate that the disinfection of L. pneumophila (half-value period: 6.7 min) by TiO2 photocatalyst in water is accompanied by remarkable cellular membrane and internal damage to L. pneumophila. Assays with limulus amebocyte lysate and silver staining showed the release of endotoxin from L. pneumophila due to membrane damage and photocatalytic degradation of this endotoxin. This is the first study to demonstrate the disinfection mechanisms of TiO2 photocatalyst, namely, via morphological changes and membrane damage of L. pneumophila. Our results suggest that TiO2 photocatalyst might be effective in controlling the spread of L. pneumophila.

Support for Recommendations of Precleaning Before Disinfection: Limited Efficacy of Soapy Water as a Disinfectant against SARS-CoV-2

The World Health Organization (WHO) and US Centers for Disease Control and Prevention (CDC) recommend cleaning soiled surfaces with soap and water, followed by use of approved disinfectant. However, data are lacking on the potential efficacy of soapy water alone as a disinfectant for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), which is relevant to low-resource settings where soapy water is prevalent for handwashing. To our knowledge, no appropriate biosafety level 1 (BSL-1) surrogate has been identified and confirmed for use in studies with soapy water and the highly infectious SARS-CoV-2. Therefore, our objectives were to determine the efficacy of soapy water alone as a disinfectant against SARS-CoV-2 and if commonly used BSL-1 bacteriophage surrogates could serve as a surrogate model for testing soapy water as a disinfectant. Overall, results indicate that SARS-CoV-2 can be reduced >4 log10 in suspension but only 0.50 log10 on a nonporous surface with 10 min of exposure to 0.5% soapy water. This difference is potentially attributed to less area of exposure on surfaces than in suspension. Phi6 (a verified SARS-CoV-2 surrogate for other disinfectants) was not appropriate for SARS-CoV-2 disinfection with soapy water. Further research is needed to determine an appropriate surrogate for SARS-CoV-2 disinfection with soapy water as disinfection of MS2 was similar to SARS-CoV-2 on surfaces only. Our work highlights the importance of confirming surrogates for each disinfectant used. Based on our results, we do not recommend a change to the current WHO and CDC surface disinfection protocols that recommend using soapy water to preclean a surface before applying disinfectant.

Virucidal activities of novel hand hygiene and surface disinfectant formulations containing EGCG-palmitates (EC16).

BACKGROUND: Non-toxic hand hygiene and surface disinfectant products with virucidal activity against alcohol-resistant nonenveloped norovirus are in urgent need. METHOD: Alcohol-based formulations were made with epigallocatechin-3-gallate-palmitate (EC16), an FDA accepted food additive. Based on in-house testing of formulations, 3 prototypes, PTV80 hand gel, PST70 surface disinfectant spray and PST70 surface disinfectant wipe, were selected from in-house tests for independent testing at GLP (good laboratory practice) laboratories according to EN 14476:2019 (hand gel), ASTM test method E1053-20 (spray), and ASTM E2362-15, E1053, and ASTM E2896-12 (wipe). RESULTS: The PTV80 hand gel prototype demonstrated a >99.999% reduction of murine norovirus S99 infectivity in 60 seconds. Carrier testing of the PST70 surface spray and surface wipe demonstrated reduction of feline calicivirus infectivity by >99.99% in 60 seconds. In addition, testing with human coronavirus and human herpes simplex virus demonstrated >99.99% efficacy in 60 seconds, consistent with broad spectrum virucidal activity. CONCLUSIONS: The novel non-toxic prototypes containing EC16 were found to be suitable for use in future hand sanitizer gel, surface disinfectant spray and wipe products against norovirus. Products based on these formulations could be used safely to help prevent and control norovirus and other emerging virus outbreaks, pending future studies.

Comparative Evaluation of Antimicrobial, Antiamoebic, and Antiviral Efficacy of Ophthalmic Formulations.

The extensive use of ophthalmic antibiotics is contributing to the appearance of resistant bacterial strains, which require prolonged and massive treatments with consequent detrimental outcomes and adverse effects. In addition to these issues, antibiotics are not effective against parasites and viruses. In this context, antiseptics could be valuable alternatives. They have nonselective mechanisms of action preventing bacterial resistance and a broad spectrum of action and are also effective against parasites and viruses. Here, we compare the in vitro antibacterial, antiameobic, and antiviral activities of six ophthalmic formulations containing antiseptics such as povidone-iodine, chlorhexidine, and thymol against Gram-positive and Gram-negative bacteria, the amoeba Acanthamoeba castellanii, and two respiratory viruses, HAdV-2 and HCoV-OC43. The results suggest that, among all the tested formulations, Dropsept, consisting of Vitamin E TPGS-based (tocopheryl polyethylene glycol succinate) in combination with the antiseptic chlorhexidine, is the one with the highest range of activities, as it works efficiently against bacteria, amoeba, and viruses. On the other hand, the solution containing PVA (polyvinyl alcohol) and thymol showed a promising inhibitory effect on Pseudomonas aeruginosa, which causes severe keratitis. Given its high efficiency, Dropsept might represent a valuable alternative to the widely used antibiotics for the treatment of ocular infections. In addition to this commercial eye drop solution, thymol-based solutions might be enrolled for their natural antimicrobial and antiamoebic effect.

Community empowerment efforts through the establishment of a COVID-19 task force to prevent the spread of COVID-19, Sukun District, Malang City

Efforts to prevent the spread of the COVID-19 virus and overcome the impact of the pandemic require the participation of community elements. The incidence of Covid-19 in RW 09, Tanjung Rejo Village, Sukun District, amounted to 15 cases with a death toll of 1 resident in December 2020. The lack of community knowledge about COVID-19 and its prevention efforts can be seen from the many residents who do not comply with health protocols, make the importance of community-based health interventions in the RW area. The intervention was carried out with 3 main programs, namely: the movement for the formation of the COVID-19 Task Force (Satgas);healthy living communities (GERMAS);and the movement for people to use masks, antiseptics, and disinfectants (GEMAD). The results of the intervention showed the formation of a COVID-19 task force tasked with disseminating the right information and increasing social support in efforts to prevent COVID-19, and increasing knowledge of the COVID-19 task force and health cadres after counseling activities were carried out. After the intervention, it is hoped that all RWs in Sukun District can empower the community to form a COVID-19 task force in an effort to prevent the spread of COVID-19.

Application of normative documents for determination of biocidal activity of disinfectants and antiseptics dedicated to the medical area: a narrative review.

Disinfectants and antiseptics are important weapons to reduce the number of micro-organisms and thus limit the number of infections. Different methods of antimicrobial activity testing, often not standardized, without appropriate controls and not validated, are applied. To address these issues, several European Standards (EN) have been developed, describing the test methods to determine whether chemical disinfectants or antiseptic products have appropriate bactericidal, sporicidal, mycobactericidal or tuberculocidal activity; fungicidal or yeasticidal activity; or virucidal activity. In this narrative review, the 17 ENs concerning evaluation of the above-mentioned antimicrobial activity of preparations dedicated to the medical area are briefly reviewed, together with recent publications on this topic. Suspension and carrier tests have been performed in clean and dirty conditions simulating the medical area. In addition, a wide range of applications of these standards has been presented in the research of biocides for hand antisepsis, surfaces disinfection, including airborne disinfection as well as medical device and medical textile disinfection. The role of normative documents in the investigation of antimicrobial activity of disinfectants and antiseptics to limit infections has been underestimated. This narrative review aims to persuade researchers to conduct antimicrobial activity testing in line with validated ENs and highlights an existing gap in ongoing research. It also aims to raise awareness of the wide range of biocidal activity tests with standardized methods in the medical area. We also pay attention to the recently developed European Pharmacopoeia monography concerning the testing of bactericidal and fungicidal activity of antiseptics classified as medicinal products.

Application of Silver Nanoparticles as a New Alternative Antiviral Agent for SARS-CoV-2: A Review

Background: Today, SARS-CoV-2 (COVID-19), a viral disease caused by the novel coronavirus (a tiny crowned virus), has become one of the threats for human beings all over the world and caused the death of millions of people worldwide. Many vaccines have been developed and administered to people in several countries;however, due to their propensity to create new strains, it appears that curing all corona strains will be challenging. So, it is necessary to identify the structure of the virus, mechanism of action, and its antiviral activities against drugs and other functional materials. Methods: AgNPs have unique physicochemical and antimicrobial properties. This review describes the structure and nature of the virus and the mechanism of action of an antiviral drug such as silver nanoparticles (AgNPs) with the virus. In addition, different methods for synthesis of AgNPs, application of AgNPs as an antiviral agent against influenza virus, human immuno deficiency virus (HIV), herpes simplex virus type 1 (HSV-1), hepatitis B virus (HBV), polio virus, respiratory syncytial virus (RSV), are discussed. Also, the most probable applications and properties of AgNPs that can help prepare it as an antiviral agent are discussed. Results: The use of AgNPs against various viruses, including the coronavirus family, is found to be effective;therefore, it can be considered for the development of antiviral agents, disinfectants, antiviral coated mask, and their therapeutic use against the treatment of novel coronavirus with minimum side effect and great efficiency. Conclusion: AgNPs were successfully used for the treatment of various viral diseases of the coronavirus family such as H1N1, H3N2, influenza, even for SARS and MERS coronaviruses. AgNPs coated masks, disinfectants, fabrics, wipes, and inhalation systems are effective for the inhibition of SARS-CoV-2 infection. Since sanitizers have a temporary effect, the development of some other potential alternatives having low toxicity, ease of use, long lasting efficiency, health cautiousness, minimum side effect, sustainable fabrics is required.

A Propidium Monoazide (PMAxx)-Droplet Digital PCR (ddPCR) for the Detection of Viable Burkholderia cepacia Complex in Nuclease-Free Water and Antiseptics

Pharmaceutical products contaminated with Burkholderia cepacia complex (BCC) strains constitute a serious health issue for susceptible individuals. New detection methods to distinguish DNA from viable cells are required to ensure pharmaceutical product quality and safety. In this study, we have assessed a droplet digital PCR (ddPCR) with a variant propidium monoazide (PMAxx) for selective detection of live/dead BCC cells in autoclaved nuclease-free water after 365 days, in 0.001% chlorhexidine gluconate (CHX), and in 0.005% benzalkonium chloride (BZK) solutions after 184 days. Using 10 μM PMAxx and 5 min light exposure, a proportion of dead BCC was quantified by ddPCR. The detection limit of culture-based method was 104 CFU/mL, equivalent to 9.7 pg/μL for B. cenocepacia J2315, while that of ddPCR was 9.7 fg/μL. The true positive rate from nuclease-free water and CHX using PMAxx-ddPCR assay was 60.0% and 38.3%, respectively, compared to 85.0% and 74.6% without PMAxx (p < 0.05), respectively. However, in BZK-treated cells, no difference in the detection rate was observed between the ddPCR assay on samples treated with PMAxx (67.1%) and without PMAxx (63.3%). This study shows that the PMAxx-ddPCR assay provides a better tool for selective detection of live BCC cells in non-sterile pharmaceutical products.

The effect of the vaccine against viral pneumoenteritis left-pointing-double-angle Bolshevak right-pointing-double-angle on the metabolism of cows

The problem of viral pneumoenteritis of young farm animals is relevant for agriculture of the Republic of Belarus. Today, the most effective method of preventing viral pneumoenteritis of calves is vaccination of pregnant cows. In case of mixed infections, the most effective means of preventing such diseases are polyvalent vaccines. But biological preparations should have not only high preventive effectiveness, but also not affect the quality of the final product. The author of the article studied the effect of a polyvalent inactivated culture vaccine against infectious rhinotracheitis, viral diarrhea, parainfluenza-3, respiratory syncytial, rotavirus and coronavirus infection of cattle left-pointing-double-angle BolsheVak right-pointing-double-angle on the state of metabolism of pregnant cows. For this purpose, 3 groups of pregnant cows of the Belarusian black-and-white Holstein breed were formed in the conditions of the Agricultural Republican subsidiary of the Ulishitsy Agro enterprise of the Gorodok district on the principle of pairs of analogues with10 animals in each group for 1.5-2 months before calving. The cows of the first experimental group were immunized with the vaccine against viral pneumoenteritis "Bolshevak" with the adjuvant ISA-15 intramuscularly into the croup area in compliance with the rules of asepsis and antiseptics in the volume of 5.0 cm3. Cows of the second experimental group were immunized with the vaccine against viral pneumoenteritis "Bolshevak" with the adjuvant ISA-25 - in the volume of 3.0 cm3. The cows of the control group were injected with isotonic sodium chloride solution according to a similar scheme. The animals were immunized twice with an interval of 21 days. The sampling was carried out before the start of the studies, on the 14th, 21st days after the first vaccination and on the 45th day after the revaccination. The clinical condition of the animals was monitored for 70 days. As a result of the research, it was found that the studied vaccine against viral pneumoenteritis does not have a negative effect on the general condition of the animal, does not cause allergic reactions, abortions, does not inhibit the synthesis of the studied biochemical parameters of the serum.