Emergence Of Antimicrobial-resistant Microorganisms Research Articles

Recent Advances in the Development of Antibiotics-Coated Gold Nanoparticles to Combat Antimicrobial Resistance.

Antimicrobial resistance (AMR) has become an alarming threat to the successful treatment of rapidly growing bacterial infections due to the abuse and misuse of antibiotics. Traditional antibiotics bear many limitations, including restricted bioavailability, inadequate penetration and the emergence of antimicrobial-resistant microorganisms. Recent advances in nanotechnology for the introduction of nanoparticles with fascinating physicochemical characteristics have been predicted as an innovative means of defence against antimicrobial-resistant diseases. The use of nanoparticles provides several benefits, including improved tissue targeting, better solubility, improved stability, enhanced epithelial permeability and causes minimal side effects. However, except for gold nanoparticles (AuNPs), the biological safety of the majority of metal nanoparticles remains a serious problem. AuNPs appear to be promising for drug delivery and medicinal applications because of their minimal toxicity, biocompatibility, functional flexibility, chemical stability and versatile biological activities, such as their antiviral, antifungal, anti-inflammatory and antimicrobial properties. Hence, we are focusing on the gold nanoparticles possessing antimicrobial activity in this article. This review will cover recent strategies in the preparation of gold nanoparticles, with special emphasis placed on antibiotics-coated AuNPs with enhanced antimicrobial properties and how they fight against disease-causing bacteria and eradicate biofilms, along with their activities and physicochemical properties.

Self-medication and its Consequences during & after the Coronavirus Disease 2019 (COVID-19) Pandemic: A Global Health Problem

Coronavirus disease 2019 (COVID-19) is a respiratory tract infection that emerged from China in December 2019 and is caused by severe acute respiratory syndrome coronavirus 2. Due to the airborne nature of its transmission, COVID-19 spread to the rest of the world rapidly. Thus, the World Health Organization declared COVID-19 a pandemic. This paper evaluated the factors that lead to self-medication in people suffering from respiratory tract infections such as COVID-19, and the consequences of practicing self-medication using antimicrobial agents. Most of the signs and symptoms of COVID-19 are also seen in infections such as malaria, flu, and the common cold. For this reason, and also due to poor healthcare-seeking behaviour, most people tend to self-medicate using medicines that are known to be effective against malaria, common cold, and COVID-19. Among the commonly used medicines in the practice of self-medication include antibacterials, antimalarials, and antivirals. Some vitamins such as vitamin C boost the immune system enabling it to provide effective defence mechanisms against microbes. However, self-medication may pose consequences such as the emergence of antimicrobial-resistant microorganisms, hypersensitivity reactions as well as dose-dependent toxicities viz dermatoxicity, cardiotoxicity, and hepatoxicity. Infectious diseases caused by antimicrobial-resistant microbes are difficult and, in some instances, impossible to treat thereby leading to increased morbidity and mortality among infected people. Consequently, antimicrobial resistance poses another global public health problem and requires a multisectoral approach to curb. It is our recommendation that all governments ensure that there are adequate medicines and efficient human resources in healthcare facilities as well as sufficient public awareness to prevent people from seeking self-medication.

Removal of antibiotics and nutrients by Vetiver grass (Chrysopogon zizanioides) from secondary wastewater effluent

Persistence of antibiotics in soil and aquatic ecosystem is the primary reason for the emergence of antimicrobial resistant microorganisms. After consumption, antibiotics are poorly retained in our body, and a major fraction is excreted out. These bioactive compounds end up in wastewater. The routine treatment practiced by the conventional wastewater treatment plants does not remove the entire load of antibiotics. Cost-effective and environment-friendly treatment technologies need to be developed to address this issue. Vetiver system is being adapted throughout the world due to its removal capacity and high tolerance toward several toxic organic and inorganic pollutants. In this study, we investigated the potential of vetiver (Chrysopogon zizanioides), a fast-growing, perennial grass capable of growing in a hydroponic setup, to remove two widely prescribed antibiotics, ciprofloxacin (CIP) and tetracycline (TTC) from secondary wastewater effluent. Significant (p < 0.05) removal of antibiotics and nutrients (N & P) by vetiver grass from secondary wastewater effluent was observed within 30 days. Vetiver grass removed more than 90% antibiotics from secondary wastewater matrix. In addition to antibiotics, vetiver grass also removed nitrate (>40%), phosphate (>60%), total organic carbon (>50%), and chemical oxygen demand (>40%) from secondary wastewater effluent.

Immunobiotics for the Bovine Host: Their Interaction with Intestinal Epithelial Cells and Their Effect on Antiviral Immunity.

The scientific community has reported several cases of microbes that exhibit elevated rates of antibiotic resistance in different regions of the planet. Due to this emergence of antimicrobial resistant microorganisms, the use of antibiotics as promoters of livestock animals’ growth is being banned in most countries around the world. One of the challenges of agricultural immunology therefore is to find alternatives by modulating the immune system of animals in drug-independent safe food production systems. In this regard, in an effort to supplant antibiotics from bovine feeds, several alternatives were proposed including the use of immunomodulatory probiotics (immunobiotics). The purpose of this review is to provide an update of the status of the modulation of intestinal antiviral innate immunity of the bovine host by immunobiotics, and the beneficial impact of immunobiotics on viral infections, focused on intestinal epithelial cells (IECs). The results of our group, which demonstrate the capacity of immunobiotic strains to beneficially modulate Toll-like receptor 3-triggered immune responses in bovine IECs and improve the resistance to viral infections, are highlighted. This review provides comprehensive information on the innate immune response of bovine IECs against virus, which can be further investigated for the development of strategies aimed to improve defenses in the bovine host.

Determination of antibiotics sensitivity profiles of bacteria isolated from raw milk

The extensive progress of dairy sectors in a developing country like Bangladesh, led to widespread use of antibiotics to improve the health and productivity of animals. Prolonged usage may lead to antibiotic residues in foods of animal origin; hence, the emergence of antimicrobial resistant microorganisms. Accurate data on the antibiotic usage in livestock treatment, antibiotic residues and antimicrobial resistances in raw milk in Bangladesh are lacking. This study aimed to investigate the types and usages of antibiotics in cattle, their potential microbial resistances in raw milk samples. To do so, a total of 54 raw milk samples were evaluated and the bacterial isolates were identified and measured for resistance to 4 antibiotics most commonly used during bacterial infection Bangladesh. Amongst all 54 (100%) isolates were positive to S. aureus and 36 (66.67%) isolates were positive to E coli. Determination of the antibiotic resistance pattern of isolates showed that all isolates of S. aureus were resistant to cefoxitin (81.48%), ampicillin (64.81%), ciprofloxacin (51.85%), and gentamycin (70.37%). E. coli showed resistance to cefoxitin (69.44%), ampicillin (83.33%), ciprofloxacin (77.78%), and gentamycin (86.11%). However multidrug resistance pattern was also found. The obtained results provide evidence that antimicrobial resistant strains of the above pathogens have become remarkably widespread in raw milk. This requires better management for antibiotic usages among livestock farmers to control sources of food contamination and reduce the health risks associated with the development of resistant microbial strainsAsian J. Med. Biol. Res. September 2016, 2(3): 396-401

Quantification of Antibiotic Residues and Determination of Antimicrobial Resistance Profiles of Microorganisms Isolated from Bovine Milk in Lebanon

The rapid growth of dairy sectors in the Middle East, particularly in Lebanon, led to extensive use of antibiotics to enhance the health and productivity of animals. Prolonged usage may lead to antibiotic residues in foods of animal origin; hence, the emergence of antimicrobial resistant microorganisms. Accurate data on the antibiotic usage in livestock treatment, antibiotic residues and antimicrobial resistances in raw milk in Lebanon are lacking. This study aimed to investigate the types and usages of antibiotics in cattle, their residual levels and the potential microbial resistances in raw milk samples. A questionnaire-based survey identified Gentamicin and Streptomycin as the most frequently used antibiotics. Selected raw milk samples from main dairy farms were then analyzed in duplicate by quantitative ELISA for the antibiotics residual levels. The mean residual levels of Gentamicin and Streptomycin were 90 and 80 μg/L, respectively; which are below the allowable maximum residue limit of 200 μg/L as set by the FAO/WHO. Staphylococcus aureus, Listeria monocytogenes, E. coli and total aerobic microorganisms isolated from the milk samples were then tested for resistance against Gentamicin and Streptomycin by the disc agar diffusion method. All the S. aureus, E. coli, and L. monocytogenes isolates showed high resistance to Gentamicin. However, 95% of S. aureus, 60% of E. coli and 58% of L. monocytogenes isolates were resistant to Streptomycin. The obtained results provide evidence that antimicrobial resistant strains of the above pathogens have become remarkably widespread in raw milk. This requires better management for antibiotic usages among livestock farmers to control sources of food contamination and reduce the health risks associated with the development of resistant microbial strains.

Caracterización y riesgos para la salud pública de la antibiorresistencia de Staphylococcus aureus en la cunicultura intensiva

The emergence of antimicrobial-resistant microorganisms, in both humans and animals, calls for the development of new strategies for administering antibiotics in order to bring these microorganisms under control and, most importantly, to prevent the risk of resistant bacteria being transmitted to animals and humans. One such microorganism, Staphylococcus aureus, especially its methicillin-resistant strains, is particularly hazardous to public health. This study, conducted in intensive rabbit farms in Spain, has demonstrated a high prevalence of S. aureus strains, 17.2% of which were found to be methicillin-resistant. The study also unveiled very high resistance to quinolones and to some forms of penicillin. This source of multidrug resistance merits special attention in view of the problems it poses for choosing suitable treatment and the risk of this resistance being transmitted to humans, either from direct contact or via the food chain.

Treatment strategies for central nervous system infections

Central nervous system (CNS) infections continue to be an important cause of mortality and morbidity. Current strategies for prevention and therapy of CNS infection are compromised by incomplete understanding of the microbial–host interactions that contribute to its pathogenesis and emergence of antimicrobial-resistant microorganisms. Our development of successful strategies in prevention and treatment of bacterial meningitis requires multifactorial concepts and approaches, which include advances in vaccinology, epidemiology of meningitis, emergence of antimicrobial-resistant pathogens, knowledge of pharmacokinetics and pharmacodynamics of antimicrobial agents, as well as the pathogenesis of meningitis. Prevention of bacterial meningitis targeting microbes has been effective, such as vaccination. The introduction of the protein conjugate vaccines against Haemophilus influenzae type b, Streptococcus pneumoniae and Neisseria meningitidis has changed the epidemiology of bacterial meningitis. Antimicrobial chemoprophylaxis is efficacious in prevention against H. influenzae type b and N. meningitidis meningitis. Suspected bacterial meningitis is a medical emergency and requires empiric antimicrobial therapy without delay, but recognition of pathogens with increasing resistance to antimicrobial agents is an important factor in selection of empiric antimicrobial regimen. A more complete understanding of the microbial–host interactions that are involved in the pathogenesis of CNS infections and associated neurologic sequelae is likely to help in developing new strategies for prevention and therapy of CNS infection.

Antimicrobial resistance: a microbial risk assessment perspective.

The emergence of antimicrobial-resistant microorganisms in both humans and food animals is a growing concern. Debate has centred on links between antimicrobial use in the production of food animals and the emergence of resistant organisms in the human population. Consequently, microbial risk assessment (MRA) is being used to facilitate scientific investigations of the risks related to the food chain, including quantification of uncertainty and prioritization of control strategies. MRA is a scientific tool that can be used to evaluate the level of exposure and the subsequent risk to human health relating to a specific organism or particular type of resistance. This paper reviews the recent applications of MRA in the area of antimicrobial resistance, and in particular, it focuses on the methods, assumptions and data limitations. Since MRA outputs are dependent on the quality of data inputs used in their development, we aim to promote the generation of good quality data by describing the properties that data should ideally possess for MRA and by highlighting the benefit of data generation specifically for inclusion in MRAs.