Background: Health care-associated infections (HAIs) are a significant public health problem worldwide, favoring multidrug-resistant (MDR) microorganisms. The SARS-CoV-2 infection was negatively associated with the increase in antimicrobial resistance, and the ESKAPE group had the most significant impact on HAIs. The study evaluated the bactericidal effect of a high concentration of O₃ gas on some reference and ESKAPE bacteria. Material and Methods: Four standard strains and four clinical or environmental MDR strains were exposed to elevated ozone doses at different concentrations and times. Bacterial inactivation (growth and cultivability) was investigated using colony counts and resazurin as metabolic indicators. Scanning electron microscopy (SEM) was performed. Results: The culture exposure to a high level of O₃ inhibited the growth of all bacterial strains tested with a statistically significant reduction in colony count compared to the control group. The cell viability of S. aureus (MRSA) (99.6%) and P. aeruginosa (XDR) (29.2%) was reduced considerably, and SEM showed damage to bacteria after O₃ treatment Conclusion: The impact of HAIs can be easily dampened by the widespread use of ozone in ICUs. This product usually degrades into molecular oxygen and has a low toxicity compared to other sanitization products. However, high doses of ozone were able to interfere with the growth of all strains studied, evidencing that ozone-based decontamination approaches may represent the future of hospital cleaning methods.

The rise in antibiotic-resistant strains of clinically important pathogens is a major threat to global health. The World Health Organization (WHO) has recognized the urgent need to develop alternative treatments to address the growing list of priority pathogens. Antimicrobial peptides (AMPs) rank among the suggested options with proven activity and high potential to be developed into effective drugs. Many AMPs are naturally produced by living organisms protecting the host against pathogens as a part of their innate immunity. Mechanisms associated with AMP actions include cell membrane disruption, cell wall weakening, protein synthesis inhibition, and interference in nucleic acid dynamics, inducing apoptosis and necrosis. Acinetobacter baumannii is a critical pathogen, as severe clinical implications have developed from isolates resistant to current antibiotic treatments and conventional control procedures, such as UV light, disinfectants, and drying. Here, we review the natural AMPs representing primary candidates for new anti-A. baumannii drugs in post-antibiotic-era and present computational tools to develop the next generation of AMPs with greater microbicidal activity and reduced toxicity.

Healthcare-associated infections (HAI) worldwide includes infections by ESKAPE-E pathogens. Environmental surfaces and fomites are important components in HAI transmission dynamics, and shoe soles are vectors of HAI. Ultraviolet (UV) disinfection is an effective method to inactivate pathogenic microorganisms. In this study, we investigated whether the SANITECH UV-C shoe sole decontaminator equipment that provides germicidal UV-C radiation could effectively reduce this risk of different pathogens. Six standard strains and four clinical MDR strains in liquid and solid medium were exposed to a UV-C System at specific concentrations at other times. Bacterial inactivation (growth and cultivability) was investigated using colony counts and resazurin as metabolic indicators. SEM was performed to assess the membrane damage. Statistically significant reduction in cell viability for all ATCCs strains occurred after 10 s of exposure to the UV-C system, except for S. enterica, which only occurred at 20 s. The cell viability of P. aeruginosa (90.9%), E. faecalis and A. baumannii (85.3%), S. enterica (82.9%), E. coli (79.2%) and S. aureus (71.9%) was reduced considerably at 20 s. In colony count, after 12 s of UV-C exposure, all ATCC strains showed a 100% reduction in CFU counts, except for A. baumannii, which reduced by 97.7%. A substantial reduction of colonies above 3 log₁₀ was observed at 12 and 20 s in all bacterial strains tested, except for A. baumannii ATCC 19606 (12 s). The exposure of ATCCs bacterial strains to the UV-C system for only 2 s was able to reduce 100% in the colony forming units (CFU) count in all ATCCs strains, S. aureus, P. aeruginosa, E. coli, A. baumannii, E. faecalis, except the S. enterica strain which had a statistically significant reduction of 99.7%. In ATCC strains, there was a substantial decrease in colonies after 4 s (sec) of exposure to the UV-C system, with a reduction ranging from 3.78–4.15 log₁₀ CFU/mL. This reduction was observed in MDR/ESKAPE-E strains within 10 s, showing that UV-C could eliminate above 3.84 log₁₀ CFU/mL. SEM showed a reduction of pili-like appendages after UV-C treatment in all strains except for E. coli (ATCC 25922). The Sanitech UV-C shoe sole decontaminator equipment from Astech Serv. and Fabrication Ltd. (Petrópolis, Brazil), effectively killed in vitro a series of ATCCs and MDR/ESKAPE-E bacteria of sanitary interest, commonly found in the hospital environment.

The novel Coronavirus Disease 2019 (COVID-19), caused by the Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) pandemic, has had a monumental impact on public health globally

Acinetobacter baumannii is an important bacterial pathogen associated with healthcare-associated infections (HAIs), especially in critically ill patients admitted to Intensive Care Units (ICU). Its ability to acquire antibiotic resistance determinants has propelled its clinical relevance. The rise in Acinetobacter infections and hospital outbreaks have been extensively described worldwide and are usually caused by carbapenem-resistant isolates. To compound the problem, Carbapenem-resistant A. baumannii (CRAb) isolates are also resistant to a wide range of other antibiotics, representing a serious threat to public health. Since 2017, A. baumannii has been listed as a critical priority pathogen that poses a great threat to human health, according to the World Health Organization (WHO). The carbapenem-resistant rates in A. baumannii are notorious around the world. However, Latin America has one of the highest in the world. Carbapenem resistance in A. baumannii is due mainly to the presence of horizontally acquired OXA-type carbapenem resistance genes, including bla_OXA-23, in most regions. Thus, this review aims to summarize the distribution of CRAb and its major carbapenem resistance mechanisms in Latin America.

The rise of antibiotic-resistant strains of clinically important pathogens is a major threat to global health security. The World Health Organization (WHO) has recognized the urgent need to develop alternative treatments to address the growing list of priority pathogens. Antimicrobial peptides (AMPs) rank among the various suggested options with proven activity and a high potential to be developed into effective agents. Many AMPs are naturally produced by living organisms and protect the host against pathogens as a part of their innate immunity. Various mechanisms associated with their antimicrobial actions include cell membrane disruption, cell wall weakening, protein synthesis inhibition, and interference in nucleic acid dynamics that can induce apoptosis and necrosis. Acinetobacter baumannii is considered a critical pathogen, and severe clinical problems have appeared with isolates resistant to current antibiotic treatments and conventional control procedures such as UV light, disinfectants, and drying. Here, we review the natural AMPs representing the primary candidates for new anti-A. baumannii drugs in a post-antibiotic era and present the use of computational tools to develop the next generation of AMPs with greater microbicidal activity and reduced toxicity.