Evolution of the SARS-CoV-2 omicron variants BA.1 to BA.5: Implications for immune escape and transmission.

The first dominant SARS-CoV-2 Omicron variant BA.1 harbours 35 mutations in its Spike protein from the original SARS-CoV-2 variant that emerged late 2019. Soon after its discovery, BA.1 rapidly emerged to become the dominant variant worldwide and has since evolved into several variants. Omicron is of major public health concern owing to its high infectivity and antibody evasion. This review article examines the theories that have been proposed on the evolution of Omicron including zoonotic spillage, infection in immunocompromised individuals and cryptic spread in the community without being diagnosed. Added to the complexity of Omicron's evolution are the multiple reports of recombination events occurring between co-circulating variants of Omicron with Delta and other variants such as XE. Current literature suggests that the combination of the novel mutations in Omicron has resulted in the variant having higher infectivity than the original Wuhan-Hu-1 and Delta variant. However, severity is believed to be less owing to the reduced syncytia formation and lower multiplication in the human lung tissue. Perhaps most challenging is that several studies indicate that the efficacy of the available vaccines have been reduced against Omicron variant (8-127 times reduction) as compared to the Wuhan-Hu-1 variant. The administration of booster vaccine, however, compensates with the reduction and improves the efficacy by 12-35 fold. Concerningly though, the broadly neutralising monoclonal antibodies, including those approved by FDA for therapeutic use against previous SARS-CoV-2 variants, are mostly ineffective against Omicron with the exception of Sotrovimab and recent reports suggest that the Omicron BA.2 is also resistant to Sotrovimab. Currently two new Omicron variants BA.4 and BA.5 are emerging and are reported to be more transmissible and resistant to immunity generated by previous variants including Omicron BA.1 and most monoclonal antibodies. As new variants of SARS-CoV-2 will likely continue to emerge it is important that the evolution, and biological consequences of new mutations, in existing variants be well understood.

Virulence factors of uropathogenic Escherichia coli (UPEC) and correlation with antimicrobial resistance.

BACKGROUND: Escherichia coli has found to be the predominant uropathogen (50-90%) in uncomplicated, community acquired urinary tract infection (UTI). Uropathogenic Escherichia coli (UPEC) express a multitude of virulence factors, which enable the bacteria to establish UTI. The objective of this study was to evaluate the presence of different phenotypic virulence markers in UPEC isolates and determine their correlation with antibiotic resistance pattern. RESULTS: Out of 105 patients, 56 (53%) were females and 49 (47%) were males. The age of the patients in the study ranged from 18 years to 87 years and majority of the patients belonged to the age group 20-29 years. Virulence factor was observed in 65% (n = 69) of UPEC and 20% (n = 22) of control isolates (P = 0.0001). Haemolysin production was observed in 34(32.3%) of uroisolates and 12 (11.4%) of control strain. Similarly, 62% of UPEC and 1% of control produced biofilm (P = 0.0001). The expression of Mannose-resistant hemagglutinin (MRHA) and mannose-sensitive hemagglutinin (MSHA) in uroisolates were 52.3% (n = 55) and 5.7% (n = 6) respectively, whereas in faecal isolates, 8.5% (n = 9) expressed MRHA and none produced MSHA. Antimicrobial resistance showed a high degree of resistance towards ampicillin, cotrimoxazole and norfloxacin. The resistance was observed in significant higher degree in biofilm formers as compared to non-formers. MDR and ESBL was observed in 51 and 46% of test strains and 9 and 7.6% of control strains (P = 0.0001). CONCLUSION: A significant association between virulence factors of UPEC and antimicrobial resistance in UPEC was present. Routine testing of these factors and co-relation with AMR is recommended. These findings will certainly help understand the pathogenicity and proper management of UTI patients, thus decreasing the improper use of antibiotics.

Clinical, etiological and antimicrobial susceptibility profile of pediatric urinary tract infections in a tertiary care hospital of Nepal.

BACKGROUND: Urinary tract infection (UTI) is one of most common pediatric infections. The study was designed to assess the clinical profile, common bacterial microorganisms causing UTI and their antimicrobial susceptibility patterns at B. P. Koirala Institute of Health Sciences (BPKIHS) hospital. METHODS: This is a prospective cross-sectional study conducted at Department of Microbiology and Infectious Diseases for 6 months (January to June 2018). A total of 1962 non-repetitive urine specimens (midstream, nappy pad, catheter aspirated) of pediatric patients (0-14 years age) suspected of UTI were obtained in the Microbiology laboratory. Clinical data was obtained from requisition form and hospital software. Culture and bacterial identification was done by using standard microbiological guidelines. Antimicrobial susceptibility testing was done by Kirby-Bauer disc diffusion method following clinical and laboratory standards institute (CLSI) guidelines. Resistance to methicillin and vancomycin were confirmed by calculating minimum inhibitory concentration using broth dilution method. RESULTS: Among 1962 samples, 314 (16%) were positive for bacterial infection. Fever, irritability and poor feeding was the most common symptoms in neonates while older children presented with fever and urinary symptoms. E. coli was reported the most common etiological agent (53%), followed by Enterococcus faecalis (22%), Klebsiella pneumoniae (7%) and Staphylococcus aureus (7%). Multidrug resistant (MDR) isolates accounted for 32% of isolates, while 5% were extensively drug resistant (XDR). Fourty percentage of gram-negative bacilli were ESBL producer, 38% of S. aureus were methicillin resistant Staphylococcus aureus (MRSA) and 5% E. faecalis were vacomycin resistant enterococci (VRE). E coli was highly resistant to Ampicillin (87%), Ceftriaxone (62%) and Ofloxacin (62%). Amikacin (11% resistance) and Nitrofurantoin (5% resistance) are the most effective drugs for gram-negative bacilli (GNB) while vancomycin and linezolid are functional against gram-positive cocci. CONCLUSIONS: High-level antimicrobial resistance was observed in pediatric UTI with alarming incidence superbugs like MDR, XDR, ESBL and MRSA. Regular surveillance should be carried out to determine the local prevalence of organisms and antimicrobial susceptibilities in order to guide the proper management of children.

Assessment of four in vitro phenotypic biofilm detection methods in relation to antimicrobial resistance in aerobic clinical bacterial isolates.

INTRODUCTION: The lack of standardized methods for detecting biofilms continues to pose a challenge to microbiological diagnostics since biofilm-mediated infections induce persistent and recurrent infections in humans that often defy treatment with common antibiotics. This study aimed to evaluate diagnostic parameters of four in vitro phenotypic biofilm detection assays in relation to antimicrobial resistance in aerobic clinical bacterial isolates. METHODS: In this cross-sectional study, bacterial strains from clinical samples were isolated and identified following the standard microbiological guidelines. The antibiotic resistance profile was assessed through the Kirby-Bauer disc diffusion method. Biofilm formation was detected by gold standard tissue culture plate method (TCPM), tube method (TM), Congo red agar (CRA), and modified Congo red agar (MCRA). Statistical analyses were performed using SPSS version 17.0, with a significant association considered at p<0.05. RESULT: Among the total isolates (n = 226), TCPM detected 140 (61.95%) biofilm producers, with CoNS (9/9) (p<0.001) as the predominant biofilm former. When compared to TCPM, TM (n = 119) (p<0.001) showed 90.8% sensitivity and 70.1% specificity, CRA (n = 88) (p = 0.123) showed 68.2% sensitivity and 42% specificity, and MCRA (n = 86) (p = 0.442) showed 65.1% sensitivity and 40% specificity. Juxtaposed to CRA, colonies formed on MCRA developed more intense black pigmentation from 24 to 96 hours. There were 77 multi-drug-resistant (MDR)-biofilm formers and 39 extensively drug-resistant (XDR)-biofilm formers, with 100% resistance to ampicillin and ceftazidime, respectively. CONCLUSION: It is suggested that TM be used for biofilm detection, after TCPM. Unlike MCRA, black pigmentation in colonies formed on CRA declined with time. MDR- and XDR-biofilm formers were frequent among the clinical isolates.

Antimicrobial Susceptibility Pattern in Opportunistic Pathogens Isolated from Immunocompromised Patients.

BACKGROUND:  Brought with the advancements in transplantation science and the development of immunosuppressive agents, immunocompromised patients characterized with defective immunity have increased throughout the world with increased risk for opportunistic infections. This study provides an overview of the antimicrobial susceptibility pattern among opportunistic pathogens isolated from immunocompromised patients.  Methods: Clinical and laboratory records of immunocompromised patients [patients with chronic kidney disease neutropenia, diabetes, rheumatic heart disease acquired immune deficiency syndrome hepatitis B, hepatitis C, who were subjected to microbiological culture analysis in the Department of Clinical Microbiology, KIST Medical College and Teaching Hospital, for 2 years (January 2019 and December 2020) were analyzed. RESULTS:  Out of 8,402 immunocompromised patients, 954 (11.4%) patients were subjected to microbiological culture analysis. Among 954 patients, 253 (26.5%) patients [median(interquartile range) age: 52(31-67) years; male 138 (54.5%)] were infected. A total of 295 pathogens were isolated from 1,331 cultured samples. Infections due to Escherichia coli (n=71, 24.1%), Klebsiella spp. (n=55, 18.6%), Acinetobacter calcoaceticus-baumannii complex (n=35, 11.9%), Candida albicans (n=30, 10.2%), and Staphylococcus aureus (n=28, 9.5%) were frequently observed. Among the bacterial isolates (n=239), 81.6% (n=195) of bacteria were ß-lactamase producers, 51.0% (n=122) were multi-drug resistant, 9.2% (n=195) were extensively-drug resistant, 0.8% (n=195) were pan-drug resistant, and 35.7% (n=10) of S. aureus were methicillin-resistant Staphylococcus aureus. CONCLUSIONS:  The majority of infection in immunocompromised patients is caused by Gram-negative bacteria, and is often associated with a higher number of ß-lactamase producers and multi-drug resistant organisms. Prescriptions of antibiotics on the grounds of antimicrobial stewardship might help to reduce the burden of antimicrobial resistance.

Persistence of a Frameshifting Deletion in SARS-CoV-2 ORF7a for the Duration of a Major Outbreak.

Australia experienced widespread COVID-19 outbreaks from infection with the SARS-CoV-2 Delta variant between June 2021 and February 2022. A 17-nucleotide frameshift-inducing deletion in ORF7a rapidly became represented at the consensus level (Delta-ORF7aΔ17del) in most Australian outbreak cases. Studies from early in the COVID-19 pandemic suggest that frameshift-inducing deletions in ORF7a do not persist for long in the population; therefore, Delta-ORF7aΔ17del genomes should have disappeared early in the Australian outbreak. In this study, we conducted a retrospective analysis of global Delta genomes to characterise the dynamics of Delta-ORF7aΔ17del over time, determined the frequency of all ORF7a deletions worldwide, and compared global trends with those of the Australian Delta outbreak. We downloaded all GISAID clade GK Delta genomes and scanned them for deletions in ORF7a. For each deletion we identified, we characterised its frequency, the number of countries it was found in, and how long it persisted. Of the 4,018,216 Delta genomes identified globally, 134,751 (~3.35%) possessed an ORF7a deletion, and ORF7aΔ17del was the most common. ORF7aΔ17del was the sole deletion in 28,014 genomes, of which 27,912 (~99.6%) originated from the Australian outbreak. During the outbreak, ~87% of genomes were Delta-ORF7aΔ17del, and genomes with this deletion were sampled until the outbreak's end. These data demonstrate that, contrary to suggestions early in the COVID-19 pandemic, genomes with frameshifting deletions in ORF7a can persist over long time periods. We suggest that the proliferation of Delta-ORF7aΔ17del genomes was likely a chance founder effect. Nonetheless, the frequency of ORF7a deletions in SARS-CoV-2 genomes worldwide suggests they might have some benefit for virus transmission.

Role of Biofilm in Bacterial Infection and Antimicrobial Resistance.

Biofilm refers to the complex, sessile communities of microbes found either attached to a surface or buried firmly in an extracellular matrix as aggregates. Microbial flora which produces biofilm manifests an altered growth rate and transcribes genes that provide them resistance to antimicrobial and host immune systems. Biofilms protect the invading bacteria against the immune system of the host via impaired activation of phagocytes and the complement system. Biofilm-producing isolates showed greater multidrug resistance than non-biofilm producers. Biofilm causes antibiotic resistance through processes like chromosomally encoded resistant genes, restriction of antibiotics, reduction of growth rate, and host immunity. Biofilm formation is responsible for the development of superbugs like methicillin-resistant Staphylococcus aureus, vancomycin-resistant Staphylococcus aureus, and metallo-beta-lactamase producing Pseudomonas aeruginosa. Regular monitoring of antimicrobial resistance and maintaining hygiene, especially in hospitalized patients are required to control biofilm-related infections in order to prevent antimicrobial resistance.

Co-infection of Hepatitis B and Hepatitis C among HIV-infected patients: A cross-sectional study from tertiary care hospital of eastern Nepal.

INTRODUCTION: This study was conducted with an objective to analyze prevalence and risk factors associated with co-infection of hepatitis B virus (HBV) and hepatitis C virus (HCV) in HIV-positive patients with reference to their CD4+ T cell status. MATERIALS AND METHODS: HIV-positive patients visiting the HIV clinic for CD4+ T cells testing at B.P. Koirala Institute of Health Sciences were tested for Hepatitis B and Hepatitis C. Data regarding age, gender, mode of HIV transmission, duration of HIV diagnosis, antiretroviral therapy status, antiretroviral therapy duration, hepatitis B or C status, and CD4+ T cells count were collected via face-to-face interview, and hospital records. The data were entered in Microsoft Excel 2019 v16.0 (Microsoft, WA, USA) and statistical analysis was performed by using statistical package for social sciences, IBM SPSS® v21 (IBM, Armonk, New York). RESULTS: Out of 474 HIV-positive patients, HIV-HBV, HIV-HCV, and HIV-HBV-HCV co-infections were seen in 2.95% (14/474), 18.14% (86/474), and 2.53% (12/474) respectively. The primary route of infection was intra-venous drug use (IVDU) in those co-infected with HBV only (8, 57.14%), HCV only (46, 53.49%), and both HBV and HCV (8, 66.67%). HIV patients infected via IVDU were 2.40 times more likely to have HIV-HCV co-infection as compared to those infected via sexual route (AOR 2.40, 95% CI: 1.49,3.86). Similarly, HIV patients with CD4+ T cells count less than 350 cells/mm3 were more likely to have HIV-HBV-HCV co-infection as compared to those with CD4 count equal to and more than 350 cells/mm3 (AOR 13.84, 95% CI: 2.90,66.10). CONCLUSION: HIV-positive patients are at high risk of hepatitis B and/or hepatitis C co-infection. Intravenous drug use, and lower CD4+T cells count are the most important risk predictors of co-infection. All HIV-positive patients should be carefully screened with hepatitis B and hepatitis C tests during their follow-up.

Significance of Hematological Biomarkers in Association to Syphilitic Patients.

BACKGROUND: Venereal syphilis is a sexually transmitted disease, involving pathological activities mediating tissue destruction by extensive tissue necrosis. As such, the goal amongst researchers has been set to the identification of effective laboratory biomarkers that can reflect the broad spectrum of disease and ultimately aid in timely diagnosis and effective treatment of syphilis. This research aimed to study the applications of hematological biomarkers associated with syphilitic patients visiting a tertiary care hospital. METHODS: A retrospective cross-sectional study was conducted in the syphilitic patients attending KIST Medical College and Teaching Hospital, Lalitpur, Nepal. A total of 25 syphilitic patients and 41 non-syphilitic participants were included. The rapid plasma reagin test and Treponema pallidum hemagglutination assay were used for the screening and confirmation of syphilis respectively. The hematological investigation was performed using a hematology analyzer. Statistical Package for Social Science version 17.0 was used for data analysis. A P value <0.05 was considered significant. RESULTS: Syphilitic patients showed significantly elevated levels of lymphocytes (39.8±11.5) (p=0.025), monocyte (1.9±0.8) (p=0.002), mean corpuscular volume (MCV) (92.6±12.9) (p=0.005), and mean corpuscular hemoglobin (MCH) (31.9±4.6) (p=0.008) and lowered levels of red blood cell (RBC) (4.2±0.3) (p=0.005) and platelets (237.2±628.6) (p=0.048) as compared to the lymphocytes (32.9±11.9), monocyte (0.6±1.2), MCV (83.9±8.8), MCH (34.3±1.5), RBC (4.6±0.7), and platelets (280.9±113.3) of the non-syphilitic participants. CONCLUSIONS: The results showed that the elevated levels of lymphocyte, monocyte, MCV, and MCH and lowered levels of RBC and platelets are highly specific hematological biomarkers for the diagnosis of patients with syphilis.

Status of Intestinal Parasitic Infections in a Tertiary Care Center.

BACKGROUND: Intestinal parasitic infections (IPIs) are diseases of serious public health concern in low- and middle-income countries, including Nepal. Such infections can cause growth retardation and increased susceptibility to other parasitic infections. Hence, this study aims to assess the prevalence of IPIs among the patients attending a tertiary care hospital in central Nepal. METHODS: Clinical and laboratory records of patients, whose stool samples were collected and transported to the Department of Clinical Microbiology, KIST Medical College and Teaching Hospital, during 2 years (January 2019 and December 2020) were examined for parasitological findings, by conventional microscopy using normal saline and iodine preparation. RESULTS: Out of 3,146 patients included in the study, 411 (13.1%) patients (median age[IQR]: 27[12-45]) were infected with the intestinal parasites. Patients of different age groups, such as 20-30 years (16.1%), 10-20 years (14.1%), and 30-40 years (13.3%) were mostly infected. Infection was more common in females (221/1572, 14.1%) than males (190/1574, 12.1%). There were 373 (90.8%) cases of IPIs due to Entamoeba histolytica, 34 (8.3%) cases due to Giardia lamblia, and 4 (0.9%) cases due to helminths. The prevalence of IPI in the first and second years was 14.5% (260/1794) and 11.2% (151/1352), respectively. IPIs were more common in summer (n=87, 12.8%) and spring(n=81, 10.8%). CONCLUSIONS: Present study showed a declined prevalence of helminth infection. However, a higher rate of protozoan infection indicated the water source contamination with fecal matters and therefore urgencies for awareness among the public about hygienic practices.

Vitamin D Deficiency among Patients Visiting Outpatient Departments in a Tertiary Care Centre: A Descriptive Cross-sectional Study.

Introduction: Vitamin D deficiency is a global health issue affecting billions of people. Its deficiency results in abnormal homeostasis of calcium and phosphorous levels in an individual and results in reduced bone mineral density, which further makes them more prone to develop osteogenic disorders, such as fractures. The aim of this study is to find out the prevalence of vitamin D deficiency among patients visiting the outpatient departments in a tertiary care centre. Methods: This was a descriptive cross-sectional study done among 582 patients visiting outpatient departments in a tertiary care centre between January 1, 2019 and July 31, 2020. The study was approved by the Institutional Review Committee (Reference number: 076/077/17) of a tertiary care centre. A convenience sampling method was used. Patients' demographic detail and serum vitamin D level were determined. Data were collected retrospectively from hospital records and analysis was performed using the Statistical Package for the Social Sciences software version 17.0. Point estimate at 95% Confidence Interval was calculated along with frequency, the proportion for binary data, and mean with standard deviation for continuous data. Results: Among 582 patients enrolled in this study, 328 (56.35%) (52.32-60.38 at 95% Confidence Interval) patients were vitamin D deficient. Vitamin D deficiency was found in 238 (72.56%) females and 257 (78.35%) aged 16 to 59 years. Finally, there were 102 (31.09%) cases of vitamin D deficiency over the winter season. Conclusions: The prevalence of serum vitamin D deficiency in the current study was lower when compared to similar studies done in similar settings and similar to the prevalence from international literature. Keywords: deficient; prevalence; vitamin D.

Co-infection of Uropathogenic Escherichia coli among COVID-19 Patients Admitted to a Tertiary Care Centre: A Descriptive Cross-sectional Study.

Introduction: Simultaneous infection of antibiotic-resistant uropathogens in patients with COVID-19 has necessitated the revision of the prescription of broad-spectrum antibiotics on the grounds of evidence-based studies and antimicrobial stewardship principles. The objective of this study was to find out the prevalence of uropathogenic Escherichia coli co-infection among hospital-admitted COVID-19 patients of a tertiary care centre. Methods: This descriptive cross-sectional study was conducted in urinary tract infection suspected COVID-19 patients admitted to a tertiary care hospital, from 25th June to 24th December 2021 after ethical clearance from the Institutional Review Committee with registration number 207707860. Convenience sampling was used. Serum procalcitonin levels were also measured. Data analysis was performed using the Statistical Package for the Social Sciences software version 17.0. Point estimate at 95% Confidence Interval was calculated along with frequency and proportion for binary data, and mean and standard deviation for continuous data. Results: Among the 49 hospital-admitted COVID-19 patients, 3 (6.12%) (0.59-12.83 at 95% Confidence Interval) were co-infected with uropathogenic Escherichia coli. Absolute non-susceptibility of Escherichia coli to antibiotics such as ceftriaxone, cotrimoxazole, nalidixic acid, gentamicin, and ampicillin was observed. All isolates were multidrug-resistant. All co-infected patients were female and had a median age of 35 years. Mean±SD value for procalcitonin in patients with co-infection (6.13±7.88 ng/ml) was six times higher than for the patients without co-infection (0.95±1.11 ng/ml). Conclusions: Escherichia coli co-infection in hospitalised COVID-19 patients was less frequent as compared to published literature. The serum procalcitonin value in patients with co-infection was substantially higher than that of patients without co-infection. Keywords: antimicrobial drug resistance; co-infection; COVID-19; Escherichia coli; procalcitonin.

Epidemiology of dengue in SAARC territory: a systematic review and meta-analysis.

BACKGROUND: Dengue is one of the common arboviral infections and is a public health problem in South East Asia. The aim of this systematic review and meta-analysis was to evaluate the prevalence and distribution of dengue in SAARC (South Asian Association for Regional Cooperation) countries. METHODS: The PubMed, PubMed Central, Embase and Scopus databases were searched for relevant studies. Statistical analysis on data extracted from the selected studied was conducted using the Comprehensive Meta-Analysis Software (CMA) version 3 software package. Proportions were used to estimate the outcome with a 95% confidence interval (CI). RESULTS: Across all studies, among cases of suspected dengue, 30.7% were confirmed dengue cases (proportion: 0.307, 95% CI: 0.277-0.339). The seroprevalence of dengue immunoglobulin (Ig)G, IgM or both (IgM and IgG) antibodies and dengue NS1 antigen was 34.6, 34.2, 29.0 and 24.1%, respectively. Among the different strains of dengue, dengue virus (DENV) strains DENV-1, DENV-2, DENV-3 and DENV-4 accounted for 21.8, 41.2, 14.7 and 6.3% of cases, respectively. The prevalence of dengue fever, dengue hemorrhagic fever and dengue shock syndrome was 80.5, 18.2 and 1.5%, respectively. Fever was a commonly reported symptom, and thrombocytopenia was present in 44.7% of cases. Mortality was reported in 1.9% of dengue cases. CONCLUSIONS: Dengue is a common health problem in South East Asia with high seroprevalence. DENV-2 was found to be the most common strain causing infection, and most dengue cases were dengue fever. In addition, thrombocytopenia was reported in almost half of the dengue cases.

Maintenance of broad neutralizing antibodies and memory B cells 1 year post-infection is predicted by SARS-CoV-2-specific CD4+ T cell responses.

Understanding the long-term maintenance of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) immunity is critical for predicting protection against reinfection. In an age- and gender-matched cohort of 24 participants, the association of disease severity and early immune responses on the maintenance of humoral immunity 12 months post-infection is examined. All severely affected participants maintain a stable subset of SARS-CoV-2 receptor-binding domain (RBD)-specific memory B cells (MBCs) and good neutralizing antibody breadth against the majority of the variants of concern, including the Delta variant. Modeling these immune responses against vaccine efficacy data indicate a 45%-76% protection against symptomatic infection (variant dependent). Overall, these findings indicate durable humoral responses in most participants after infection, reasonable protection against reinfection, and implicate baseline antigen-specific CD4+ T cell responses as a predictor of maintenance of antibody neutralization breadth and RBD-specific MBC levels at 12 months post-infection.

Broadly-Neutralizing Antibodies Against Emerging SARS-CoV-2 Variants.

The emergence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variants have become a major concern in the containment of current pandemic. The variants, including B.1.1.7 (Alpha), B.1.351 (Beta), P1 (Gamma) and B.1.617.2 (Delta) have shown reduced sensitivity to monoclonal antibodies, plasma and/or sera obtained from convalescent patients and vaccinated individuals. Development of potent therapeutic monoclonal antibodies (mAbs) with broad neutralizing breadth have become a priority for alleviating the devastating effects of this pandemic. Here, we review some of the most promising broadly neutralizing antibodies obtained from plasma of patients that recovered from early variants of SARS-CoV-2 that may be effective against emerging new variants of the virus. This review summarizes several mAbs, that have been discovered to cross-neutralize across Sarbecoviruses and SARS-CoV-2 escape mutants. Understanding the characteristics that confer this broad and cross-neutralization functions of these mAbs would inform on the development of therapeutic antibodies and guide the discovery of second-generation vaccines.

Metallo-ß Lactamase Producing Non-Fermentative Gram-Negative Bacilli from Various Clinical Isolates in a Tertiary Care Hospital: A Descriptive Cross-sectional Study.

INTRODUCTION: Non-fermentative gram-negative bacilli are common causes of human infections especially nosocomial infections. These organisms are usually resistant to multiple antimicrobial agents including carbapenems. The study aimed to find out the prevalence of metallo-ß-lactamase producing non-fermentative gram-negative bacilli among the samples which yielded growth of bacteria in a tertiary care hospital. METHODS: This is a descriptive cross-sectional study conducted in a tertiary care hospital from February 2017 to May 2017. Convenience sampling method was used. Bacterial identification, characterization and antimicrobial susceptibility testing were done by following standard microbiological guidelines. Metallo-ß-lactamase production was detected by using combined disk diffusion test and double-disc synergy test. Data were analyzed by using Statistical Package of Social Science software version 16. Point estimate at 95% confidence interval was calculated along with frequency and proportion for binary data. RESULTS: Among 628 samples which yielded growth of bacteria, 118 (18.79%) at 95% Confidence Interval (15.74-21.84) were metallo-ß-lactamase producing non-fermentative gram-negative bacilli. Among them, 54 (45.76%) were Pseudomonas aeruginosa and 64 (54.24%) were Acinetobacter baumannii. CONCLUSIONS: A high prevalence of metallo-ß-lactamase production was observed among the nonfermentative gram-negative bacilli than the study done in similar settings. It is mandatory to perform routine monitoring of metallo-ß-lactamase producing isolates in clinical laboratories in order to help the clinicians prescribe proper antibiotics.

Methicillin-resistant Staphylococcus aureus in Nepal.

Staphylococcus aureus is both a frequent commensal and a leading cause of endocarditis, bacteremia, osteomyelitis and skin and soft tissue infections and device-related infections. We performed this minireview to summarize the prevalence of Staphylococcus aureus among clinical samples and estimate the proportion of methicillin-resistant Staphylococcus aureus. The prevalence of Staphylococcus aureus among clinical isolates in Nepal is 34.5%. On average, the proportion of multi-drug resistance in Staphylococcus aureus is 57.1%. Methicillin-resistant Staphylococcus aureus accounts for a total of 41.7%. Inducible clindamycin resistance was detected in about 35% of the isolates. A regular antimicrobial resistance surveillance mechanism is necessary to mitigate the development of resistance among organisms and further spread of superbugs like methicillin-resistance Staphylococcus aureus.

Standard Operating Procedure for Specimen Collection, Packaging and Transport for Diagnosis of SARS-COV-2.

Coronavirus disease-19 is caused by severe acute respiratory syndrome coronavirus-2 (SARSCoV-2). Specimen quality, and proper transportation is vital for accurate diagnosis. This standard operating procedure is designed to educate the clinicians, nurses, paramedics, and laboratory personnel regarding proper methods of sample collection, packaging, and transportation. Nasopharyngeal swabs and/or oropharyngeal swabs should be collected for real-time quantitative polymerase chain reaction to detect SARS-CoV-2. The sample should be collected wearing proper personal protective equipment, packed in a triple packaging system, and transported maintaining cold chain.