Coronavirus disease 2019 (COVID-19): A New Pandemic and its Challenges

Emerging of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has caused a worldwide outbreak and a major public health problem. The present review was conducted to provide brief information about the origin, symptoms, transmission, pathogenesis, diagnosis, and treatment of the virus. A search was performed in the databases of PubMed, Scopus, Science Direct, and Google scholar with English keywords including 2019-nCoV, Coronavirus disease 2019 (COVID-19), SARS-CoV-2, and novel coronavirus from December 2019 to 15 March 2020, and the search results were evaluated. Selected studies have shown that the virus may have originated from the bat. It has also been shown that the virus receptor is angiotensin-converting enzyme 2 (ACE2) which is also the SARS virus receptor and is expressed in most human tissues. The most common way of virus transmission was suggested through respiratory droplets and close contact. It is also transmitted by asymptomatic patients, but vertical transmission from mother to fetus has not been confirmed. Real-time reverse transcriptase (RT)-PCR is the gold standard for SARS-CoV-2 detection, but chest computed tomography (CT) can be more sensitive to detect positive cases. Since no effective vaccine or drug for prevention and treatment of this disease has not yet been identified and also because of the high incubation and infection period, easy transmission, and the lack of complete recognition of the characteristics and stability in different environments, the best way to control of COVID-19 is to prevent the spread of the infection in different ways and take seriously personal and public hygiene

An overview of nanoparticle production from plant gums and their action as antimicrobial agents

There have been various chemicals and routines for the treatment of infections. The extensive use of antibiotics has led to serious issues including antibiotic resistance and serious side effects. The use of plant gum nanoparticles (NPs) is one of the several ways that can be employed greatly for the treatment of infections and have gained so much popularity by the scientists recently due to their several advantages over chemicals including being nontoxic and providing better tolerance to the patient. Several studies have been performed recently, stressing the undeniable advantages of these substances in the treatment of illnesses compared with their chemical counterparts. There are studies suggesting that these NPs have great potential in the treatment of multi-drug-resistant bacteria and that these substances have great anti-cancer effects due to their anti-inflammatory roles. Among various plant gums, Gum Arabia, gum Karaya, Kondagogu gum, and gum Tragacanth, Guar gum, and gum Ghatti have gathered more interest as anti-inflammatory subjects for studies because of their several pros including having more tissue bio-availability, being easy to use, etc. The use of plant gums can be limited due to a series of disadvantages but this can be untangled by using natural nanoparticles which can be synthesized via several ways including ultrasonic irradiation, etc. Among various metallic NPs, the most frequent of them in these studies are Silver nanoparticles (AgNPs) and Gold nanoparticles (AuNPs). According to these studies, AgNPs have a more bactericidal effect than AuNPs which is due to them being more of an antioxidant

Plant Gum Based Drug Carriers

Recently, there have been various chemical carriers and routines for treatment of infections. Plant gum nanoparticles are being used greatly for this purpose. They have several advantages over chemical drug carriers including being biodegradable, biocompatible, nontoxic, providing better tolerance to the patient, and having fewer side effects. They also do not cause allergies in humans, do not irritate the skin or eyes, and have low production costs. The use of plant gums as drug carriers is limited due to a series of disadvantages. They may have microbial contamination because of the moisture in their content. Also, in storage, their viscosity decreases due to contact with water. By green nanoparticle synthesis of these plant gums as drug carriers, the disadvantages can be limited. There are several studies showing that plant gum drug carriers can have a great combination with various drugs and nanoparticles, thus they could be extremely effective against multi-resistant bacteria and even systemic illness like cancer. These days, the need for green synthesis of medicine and drug carriers has become quite popular and it will be even more essential in the future because of emerging antibiotic-resistant bacteria and climate change

Latent tuberculosis infection in health care workers: review article

The members of Mycobacterium tuberculosis complex (MTBC) known as causative agents of human tuberculosis. Tuberculosis infection is one of the most important occupational risks for healthcare workers (HCWs) in most countries, such as Iran. In general, there are two types of tuberculosis, they include: latent infection and active TB. Latent tuberculosis infection (LTBI) means: a patient is infected with Mycobacterium tuberculosis but, the patient does not have active tuberculosis, clinical symptoms and radiological findings. According to studies, TB infection from patients to health care workers, depending on geographic region and economic situation is two to five times more than general population. The lowest incidence and the highest rates of LTBI prevalence among HCWs were 7% in Mashhad and 82.8% in Zahedan respectively. The risk factor acquisition of TB infection was a significant relationship with certain hospital wards (lung disease unit, laboratory, etc.), Increasing age and duration of employment. And results of this study show that TB is a significant problem among HCWs in Iran. Infection control and personal protective measures with training programs to patients and HCW is required to reduce the occupational risk of TB. Early detection of Mycobacterium tuberculosis and prevention treatment in people with latent TB are key elements in control of tuberculosis. Until now, different methods for detection of latent tuberculosis infection has been introduced that are not gold standard none of them. However, the most important methods, tuberculin skin test and the tests that based on measuring the production of interferon gamma are recommended, but each one of them has advantages and disadvantages. However, in all the articles of the tuberculin skin test is used for screening and early diagnosis of latent tuberculosis infection. So, the aim of this study was to Incidence and prevalence of latent tuberculosis infection in health care workers and risk factors, advantages and disadvantages of each method for diagnosis of latent tuberculosis infection and evaluate different strategies for reducing the incidence of latent tuberculosis infection in health care workers

Comparison of phenotypic detection of extended spectrum beta-lactamases using the E-test ESBL and combined disk method clinical isolates of Klebsiella pneumoniae: brief report

Background: Antimicrobial resistance is a growing problem in many bacterial pathogens and is of particular concern for hospital-acquired nosocomial infections. Klebsiella pneumonia is an important cause of nosocomial infections has rapidly become the most common extended spectrum beta-lactamases (ESBLs) producing organism. ESBL are defined as the enzymes capable of hydrolyzing oxyimino-cephalosporins. The aim of this study was to compare phenotypic detection of ESBL using two phenotypically method among the clinical isolates of Klebsiella pneumoniae. Methods: In this cross-sectional study a total of 144 isolates from clinical samples Urine, sputum, wound, blood, throat and body fluids isolated and identified as K. pneumoniae in a teaching hospitals in Shiraz within a six months period from December 2012 to May 2013. Antibacterial susceptibility test performed to 14 antibiotics by the disk diffusion method according to CLSI guideline and then isolates that were resistant to at least one of the beta-lactam antibiotics evaluated for the production of beta-lactamase enzymes by using E-test ESBL and combined disk method. Results: Totally 38 (26.3%) isolates produced ESBLs. All ESBL producing isolates were susceptible to imipenem and meropenem and resistant to aztreonam. The highest antibiotic resistance was observed for amoxicilin (100%) and the lowest antibiotic resistance was observed for meropenem (9.7%). The number of 38 (100%) isolates were identified as ESBL producer by using E-test ESBL ceftazidime. It was while using the combined disks; ceftazidime/clavulanic acid, cefotaxime/clavulanic acid and cefpodoxime/clavulanic acid, respectively 35 (92.1%), 34 (89.4%) and 31 (81.5%) of isolates identified as beta-lactamase producing isolates. Conclusion: Considering the high prevalence of bacteria producing ESBL, screening for infections caused by ESBL-producing isolates may be lead to the most effective antibiotics therapies

Detection of efflux pump genes in multiresistant Acinetobacter baumannii ST2 in Iran

Acinetobacter baumannii, as a nosocomial pathogen has become a worldwide concern in recent years. In the current study, the resistance to tetracyclines and colistin were assessed in the isolates from different provinces of Iran. During the timeline of this study, a number of 270 isolates of A. baumannii were collected from tracheal aspirates, wounds, urine and blood cultures. The minimum inhibitory concentration (MIC) for tetracycline, doxycycline, minocycline, tigecycline and colistin were evaluated. Tetracycline resistance genes were assessed by PCR. The mean expression level of adeB, adeJ and adeG were assessed using semi quantitative Real-Time PCR. The clonal relationship of the isolates was evaluated by the repetitive extragenic palindromic PCR (REP-PCR), International Clonal (IC) Lineage Multiplex PCR and multilocus sequence typing (MLST) (Pasteur scheme) methods. The MIC by microdilution method showed that 87.5, 51.4, 28, 0.74 and 0% of the isolates were resistant to tetracycline, doxycycline, minocycline, tigecycline and colistin respectively. The prevalence of tetracycline resistance genes was 99.2, 99.2, 98, 86.7, 10, 3.33, 0.37, 0% for adeB, adeJ, adeG, tetB, tetA(39), tetA, tetM and tetH in tetracycline-resistant isolates. Moreover, the expression level of adeB, adeJ, adeG genes in tigecycline-nonsusceptible A. baumannii (TNAB) strain was higher compared to the tigecycline-susceptible A. baumannii (TSAB). A broad genomic diversity was revealed, but ST2 was the most prevalent ST. Our results indicated that tetracycline resistance in Iran is mediated by resistance-nodulation-cell division (RND) and tetB efflux pumps