2,447 publications found
Sort by
Molecular detection and characterization of SARS-CoV-2 in wastewater in Thailand during 2020-2022.

SARS-CoV-2 has been detected in feces of infected individuals and in wastewater in many countries, which indicates that wastewater may be used to monitor contamination of the virus in community. However, information about the presence of SARS-CoV-2 in different types of environmental water and their genetic characterization are still limited. The purpose of this study was to investigate the presence of SARS-CoV-2 contaminating in environmental water in Thailand. We collected 600 water samples from 10 different sampling sites in Chiang Mai city, Thailand twice a month from July 2020 to December 2022. The SARS-CoV-2 RNA was detected by real-time RT-PCR and further amplified for ORF1a and S genes to investigate their genetic relationship to the reference strains by phylogenetic analysis. SARS-CoV-2 was detected at 0.17% in the wastewater sample collected in the vicinity of fresh market where the outbreak of COVID-19 cases were simultaneously reported. The detected SARS-CoV-2 strain (W323/21) had nucleotide and amino acid sequences identical to SARS-CoV-2 Delta variant. Amino acid sequence alignment of spike protein revealed that the W323/21 strain carried a mutation of D950N as it was demonstrated in Delta variant reference strains. The findings indicated that SARS-CoV-2 Delta variant was detected in wastewater in Chiang Mai, Thailand during the outbreak of COVID-19, suggesting a circulation of the virus in environmental water and in the community during the outbreak.

Open Access
Relevant
Long-term comparisons of the durability of 6 months versus 12 months antiviral therapy for hepatitis B after chemotherapy cessation.

Prophylaxis antiviral therapy is recommended for patients with hepatitis B receiving chemotherapy but the ideal treatment duration after chemotherapy cessation needs more evidence for clarification. This study aimed to compare the relapse rate of short finite intervals of 6 months and 12 months of -nucleos(t)ide analogue (NA) therapy in patients stratified by low hepatitis B virus (HBV)-DNA of <2000 IU/ml or high HBV DNA of ≥2000 IU/ml. Patients started tenofovir or entecavir treatment 1 week before chemotherapy and were assigned to different treatment duration groups randomly after stratified by HBV DNA pretreatment: (1) HBV DNA of <2000 IU/ml at 6-month or 12-month duration; (2)HBV DNA of ≥2000 IU/ml at 6-month or 12-month duration. Virological relapse (VR) was defined as HBV DNA of >2000 IU/ml, and clinical relapse (CR) was defined as HBV DNA of >2000 IU/ml and alanine aminotransferase of >80 IU/L during the follow-up period. The primary endpoint was to compare the durability between groups 1 year after antiviral therapy cessation. The secondary endpoint was VR and CR rate at long-term follow-up after antiviral therapy cessation. This study enrolled 61 patients, and 5 patients were lost to follow-up or tumor recurrence. VR and CR rates were 46.4% and 14.3% at 1-year and 55.3% and 16.1%, at long-term follow-up, respectively. VR and CR rates demonstrated no difference between the groups. Pretreatment HBV DNA at ≥2000 IU/ml and end-of-treatment hepatitis B surface antigen (HBsAg) at ≥500 IU/ml were the predictor of VR (hazard ratio [HR]: 2.98; p=0.010 and HR: 2.38; p=0.037). Prolongation from 6 months to 12 months of NA consolidation after chemotherapy cessation did not affect the VR or CR of HBV. High pretreatment HBV DNA and end-of-treatment HBsAg levels could predict VR after antiviral therapy cessation for chemotherapy.

Open Access
Relevant
Molecular epidemiology, antibiogram profile and risk factor analysis of pathogenic Escherichia coli associated with pre-weaning diarrhoea in piglets from Haryana, India.

Piglet diarrhoea is a multifactorial disease with serious implications for the swine industry worldwide, including India. The Escherichia coli (E. coli) pathotypes, i.e., enterotoxigenic E. coli (ETEC) and Shiga toxin-producing E. coli (STEC) are among the major bacterial agents attributed as causative agent for piglet diarrhoea, but studies related to genetic diversity, antibiogram profile and their correlation with risk factors of these pathogens are sparse. A total of 104 faecal swab samples were collected from 32 different piggery units of Haryana, India and confirmed as E. coli by standard microbiological methods. The identified E. coli were characterized as ETEC and/or STEC using PCR assays and were studied for their genetic diversity by phylogenetic analysis of the sequences. All the isolates were subjected to antimicrobial susceptibility testing. Further, the correlation of variables with presence or absence of ETEC and/or STEC was also investigated by using Fisher's exact test. Microbiological isolation led to identification of 208 E. coli isolates. A total of 17.3% (31/208) isolates were characterized as ETEC and 4.8% (10/208) isolates as STEC, whereas 2.4% (5/208) isolates exhibited both ETEC and STEC pathotype. Of the total studied piggery units (n=32), ETEC were isolated from fourteen and both ETEC and STEC from eight farms. The phylogenetic analysis of Stx2 gene revealed 100% homology with Stx2eA variant from Germany, while analysis of STII gene revealed a distinct nucleotide and amino acid substitution when compared with standard strains. The antibiotic susceptibility testing revealed maximum resistance to moxifloxacin (71.9%) followed by tetracycline (58.1%) and amoxicillin with a total of 41.8% (87/208) E. coli isolates designated as multi-drug resistant (MDR). The multiple antibiotic resistance index varied from 0.05 to 0.75. The statistical analysis suggested three factors viz., number of farm worker(s), frequency of using disinfectant for floor cleaning and use of antibiotic in feed as risk factors significantly associated (p<0.05) with ETEC associated diarrhoea at piggeries under study. Current study warrants a need for systematic studies on the ETEC/STEC associated diarrhea and antibiotic resistance among these isolates to understand the mechanisms of origin and dissemination of drug resistant pathogens and to design suitable prevention and control measures to curb emergence of antibiotic resistance in the farm settings.

Open Access
Relevant
Prevalence of carbapenemase producing Enterobacterales colonization and risk factor of clinical infection.

Carbapenemase-producing Enterobacterales (CPE) are global concerns in infection control, and the number of CPE outbreaks in hospitals is increasing despite the strengthening of contact precautions. This study aimed to confirm the prevalence and transition rate of CPE infection from stool surveillance culture and to identify the acquisition pathway of CPE. This is a longitudinal review of patients with stool surveillance cultures at a tertiary center in Seoul, South Korea, from July 2018 to June 2020. Pulsed-field gel electrophoresis, multi-locus sequence typing, and whole genome sequencing were performed for carbapenemase-producing Klebsiella pneumoniae and Escherichia coli strains. Among 1620 patients who had undergone stool CPE surveillance cultures, only 7.1% of active surveillance at the Emergency Room (ER) and 4.4% of universal surveillance in the Intensive Care Unit (ICU) were stool CPE positive. The transition rates from stool carriers to clinical CPE infections were 29.4% in the ER and 31.3% in the ICU. However, it was significantly high (55.0%) in the initial stool CPE-negative ICU patients. Among the initial stool CPE-positive patients, hypertension (61% vs. 92.3%, P=0.004), malignancy (28.8% vs. 53.8%, P=0.027), and mechanical ventilation (25.4% vs. 53.8%, P=0.011) were significant risk factors for clinical CPE infection. Molecular typing revealed that sequence type (ST) 307 and ST 395 were dominant in K. pneumoniae, and ST 410 was dominant in E. coli isolates. Active surveillance showed a higher detection rate than universal stool CPE screening, and one-third of positive stool CPE specimens ultimately developed subsquent clinical CPE infection. According to the molecular typing of the identified CPE strains, in-hospital spread prevailed over external inflow, and the transition rate to clinical CPE was particularly high in the ICU. Therefore, in order to control CPE propagation, not only active surveillance to block inflow from outside, but also continuous ICU monitoring within the hospital is necessary.

Open Access
Relevant
The transmutation of Escherichia coli ATCC 25922 to small colony variants (SCVs) E. coli strain as a result of exposure to gentamicin.

Small colony variants (SCVs) are biotypes of bacteria that have a size of approximately one-tenth or less of the wild types and has distinct characteristics comparing to the wild type strains. Clinical SCVs are usually associated with persistent infection and require a long-term treatment program with antibiotics. In Saudi Arabia, there are few studies about SCVs Escherichia coli for this reason, this study is aimed to investigate the ability of gentamicin to mutate E. coli ATCC 25922 to produce small SCVs and investigate the genotypes and phenotypes changes and stress tolerance comparing to clinical SCVs E. coli and normal clinical E. coli Isolated from blood samples. In this investigation, four clinical blood samples were collected ted from patients and the cultivation and isolation were carried out in KFMC between December 2019 and February 2021. The identification of positive blood culture samples was done using phoenix MD. Non-SCV E. coli ATCC25922 were mutated to SCV using exposure to increasing gradual concentrations of gentamicin at 100-generation intervals. Biochemical features and susceptibility to standard antibiotics using automated Phoenix MD 50 and. The survival assays were done using several stresses including heat shock, low pH, high osmotic pressure, and oxidative pressure. Virulence genes screening included the detection of genes that encoded to α-haemolysin, CS12 fimbriae, F17-like fimbrial adhesion, P-related fimbriae, yersiniabactin siderophore system, P-fimbriae, aerobactin, iron-regulated genes using PCR and gel electrophoresis. The data from the mutating E. coli ATCC 25922 small colony test with gentamicin revealed that the first emergence of the multidrug resistance (MDR) SCV E. coli strain occurred at generation number 250, corresponding to a gentamicin concentration of 57g/ml. Pathogenicity islands detection revealed that all tested E. coli strains have PAI IV 536 genes on their chromosomes furthermore, mutated SCV E. coli ATCC 25922 acquired PAII CFT073 and PAI IV 536. Survival tests showed no significant differences changes in tolerance of mutated SCVs comparing to parental strain. The present work concluded that gentamicin sub-MIC concentration gradual exposure can induce mutation responsible for SCV formation and evolving of MDR E. coli strains. The mutated SCVs evolved high-level aminoglycoside resistance for gentamicin and resistance to amikacin, it also developed resistance to 2 cephalosporin antibiotics cefuroxime, and cephalothin and a resistance to aztreonam.

Open Access
Relevant
Follow up and comparative assessment of IgG, IgA, and neutralizing antibody responses to SARS-CoV-2 between mRNA-vaccinated naïve and unvaccinated naturally infected individuals over 10 months.

Evidence on the effectiveness of vaccination-induced immunity compared to SARS-CoV-2 natural immunity is warranted to inform vaccination recommendations. In this study, we aimed to conduct a comparative assessment of antibody responses between vaccinated naïve (VN) and unvaccinated naturally infected individuals (NI) over 10 Months. The study comprised fully-vaccinated naïve individuals (VN; n=596) who had no history of SARS-CoV-2 infection, and received two doses of either BNT162b2 or mRNA-1273, and naturally infected individuals who had a documented history of SARS-CoV-2 infection and no vaccination record (NI cohort; n=218). We measured the levels of neutralizing total antibodies (NtAbs), anti-S-RBD IgG, and anti-S1 IgA titers among VN and NI up to ∼10 months from administration of the first dose, and up to ∼7 months from SARS-CoV-2 infection, respectively. To explore the relationship between the antibody responses and time, Spearman's correlation coefficient was computed. Furthermore, correlations between the levels of NtAbs/anti-S-RBD IgG and NtAbs/anti-S1 IgA were examined through pairwise correlation analysis. Up to six months, VN individuals had a significantly higher NtAb and anti-S-RBD IgG antibody responses compared to NI individuals. At the 7th month, there was a significant decline in antibody responses among VN individuals, but not NI individuals, with a minimum decrease of 3.7-fold (p<0.001). Among VN individuals, anti-S1 IgA levels began to decrease significantly (1.4-fold; p=0.007) after two months, and both NtAb and S-RBD IgG levels began to decline significantly (NtAb: 2.0-fold; p=0.042, S-RBD IgG: 2.4-fold; p=0.035) after three months. After 10 months, the most significant decline among VN individuals was observed for S-RBD-IgG (30.0-fold; P<0.001), followed by NtAb (15.7-fold; P<0.001) and S-IgA (3.7-fold; P<0.001) (most stable). Moreover, after 5 months, there was no significant difference in the IgA response between the two groups. These findings have important implications for policymakers in the development of vaccination strategies, particularly in the consideration of booster doses to sustain long-lasting protection against COVID-19.

Open Access
Relevant
Evaluation of an adjusted MEWS (Modified Early Warning Score) for COVID-19 patients to identify risk of ICU admission or death in the Kingdom of Bahrain.

While most COVID-19 cases have uncomplicated infection, a small proportion has the potential to develop life-threatening disease, as such development of a prediction tool using patients baseline characteristics at the time of diagnosis should aid in early identification of high-risk groups and devise pertinent management. Hence, we set up this retrospective study to determine preadmission triaging tool to predict the development of severe COVID-19 in the Kingdom of Bahrain MATERIALS AND METHODS: A retrospective study was conducted from 1 September 2020 to 30November 2020 with enrolment of all SARS-CoV-2 PCR-confirmed persons aged ≥14 years who attended Al-Shamil Field Hospital (SFH) in the Kingdom of Bahrain for triaging and assessment with recording of the following parameters: systolic blood pressure, heart rate, respiratory rate, temperature, the alert, verbal, pain, unresponsive neurological score, age, oxygen saturation, comorbidities, Body Mass Index (BMI), duration of symptoms and living with immunocompromised populations to develop our local adjusted MEWS as predictor for ICU admission & for consideration of suitable isolation at home. Follow up data of all patients was obtained from the electronic medical records system including CXR findings, treatments/medications received, need of oxygen supplements /intubation, needs of ICU care, and the outcome (death /discharged alive) IBM SPSS statistic version 21 program was used for data analysis. Our study showed that using the locally developed adjusted MEWS score, there was an significant association between high value of this adjusted MEWS score and abnormal radiographic finding (49.7 % Vs. 17 % for patients with high score Vs. those with low score respectively). Out of the 181 patients with high scores on adjusted MEWS; 38.7 % required oxygen via nasal cannula, 14.4 % required face mask and 8.3 % non-rebreather mask; this proportion was significantly higher than their counterpart patients who score low on adjusted MEWS (20.9 %, 7.7 %, 4.8 %respectively) with statistically significance difference between the two groups (p value of 0.00, 0.00,.004 respectively) Requirement of ICU admission was significantly higher among patients with high score in comparison to those with low score (14.4 % vs. 3 %) with significant p value (0.00) But higher score value was not associated significantly with increase mortality rate among COVID patients. Development of our new Adjusted MEWS score system by adding the additional elements of age, oxygen saturation, comorbidities, Body Mass Index (BMI) and duration of symptoms found to be very useful predictor tool for preadmission triaging of COVID patients based on their risk assessment to help clinician to decide on the appropriate placement to different level of isolation facilities.

Open Access
Relevant
Flu vaccination coverage in Italy in the COVID-19 era: A fuzzy functional k-means (FFKM) approach.

In Europe, flu vaccination coverage has decreased, and there are complex barriers to overcome to vaccinate against flu. Many studies have been conducted to estimate vaccination coverage. The COVID-19 pandemic threatens to disrupt immunization programs in many countries, including Italy, where vaccination against the flu is recommended but not mandatory. This paper aims to understand changes in flu vaccine uptake in Italian regions. Using functional data analysis and fuzzy functional k-means clustering, we investigated changes in flu vaccine coverage in Italian regions before (2010-2019) and after (2020-2022) the COVID-19 vaccination period. The period of COVID-19 pandemic brought an increase in vaccine coverage globally. Elbow's method determined that the optimal number of clusters in vaccination uptake is 2. Apulia, Basilicata, Emilia Romagna, Liguria, Molise, Tuscany, and Umbria in 2019 belong less to the group with low flu vaccination uptake (G1) but increase their tendency to belong to this group over time: they decrease their propensity to be vaccinated for flu. For others, it seems that COVID-19 served as a push to increase flu vaccination coverage rates. Sicily appears to be the region that has responded best to the pandemic, changing its membership value from 2019 to 2022. The present study highlights that the COVID-19 era has resulted in a higher flu vaccination coverage rate. Moreover, the regional level's improvement or worsening in flu vaccination coverage rate is not affected by the historical gap and socio-cultural and economic differences prevailing among Italian regions.

Relevant