Effect of physical, chemical and biological treatment on the removal of five pharmaceuticals from domestic wastewater in laboratory-scale reactors and full-scale plant

PhD ThesisPharmaceuticals and their metabolites are known to enter the environment from the effluent of wastewater treatment plants. From statistical analysis on the usage of pharmaceuticals, and their effects on the environment, five pharmaceuticals were selected for this study (Metronidazole, Trimethoprim, Sulphamethoxazole, Paracetamol and Ranitidine). Trace concentrations of pharmaceuticals were determined using a sensitive analytical method, comprising solid phase extraction (SPE) and liquid chromatography with a mass spectrometry detector (LC- MS),operating in selected ion monitoring (SIM) mode. It was found that Metronidazole, Trimethoprim, Sulphamethoxazole, Paracetamol and Ranitidine were detected at the highest levels in the wastewater entering the Sulaibiya WWTP Kuwait, with concentrations of up to 58 ng.L , 1814 ng.L , 1669 ng.L , 2086 ng.L and 2009 -1 ng.L , respectively. High removal efficiencies of these pharmaceuticals were found in the Sulaibiya WWTP. One year study was conducted to investigate the occurrence, persistence and fate of a range of these pharmaceuticals at different sampling points at the Sulaibiya WWTP. The treatment processes consisted of screening, grit removal and diffused air activated sludge treatment (primary and secondary treatment), followed by microfiltration (MF), reverse osmosis (RO), and chlorine oxidation (tertiary treatment). During primary and secondary treatment, Metronidazole, Trimethoprim, Sulphamethoxazole, Paracetamol and Ranitidine were removed efficiently with average removals efficiencies of 83.4%, 86.1%, 77.5%, 97.5% and 77.5%, respectively. The RO system lowered these pharmaceuticals further, giving overall removal efficiencies of 97%, 99%, 99%, 100% and 100% for Metronidazole, Trimethoprim, Sulphamethoxazole, Paracetamol and Ranitidine, respectively. All selected pharmaceuticals were tested in laboratory scale reactors to assess their -1 removal by chlorination and ozonation, and results showed that 10 mg.L of chlorine -1 removed these pharmaceuticals better than 15 mg.L of ozone. Lab-scale aerobic reactors (2 L), seeded with activated sludge inoculum from the Sulaibiya WWTP and fed with different concentrations of pharmaceuticals (0.1, 1 and -1 10 mg.L ), spiked individually into a synthetic wastewater showed that the TOC could be removed efficiently without inhibition by these pharmaceuticals. The fate of Metronidazole, Trimethoprim, Sulphamethoxazole, Paracetamol and Ranitidine was investigated in a membrane bioreactors (MBR), and a sequencing batch reactors (SBR), operating under strictly aerobic, and anoxic/aerobic conditions at different concentrations of a pharmaceutical mixture (PM) of the same -1 -1 -1 pharmaceuticals (1 µg.L , 1 mg.L and 10 mg.L ). The COD and TOC removal -1 efficiency decreased when the PM concentration was increased to 10 mg.L . The removal of Metronidazole and Trimethoprim was moderately effective, and similar in all the reactors. Sulphamethoxazole and Paracetamol were removed efficiently, but -1 this decreased when the PM was increased to 10 mg.L for most of the reactors, whilst Ranitidine experienced high removal rates at all concentrations in all the reactors. Analysis of the microbial diversity in laboratory reactors treating pharmaceuticals wastewater showed decreases in microbial community diversity when the PM concentration was increased. Pure cultures of bacteria isolated on selected pharmaceutical growth media were also detected in the microbial communities of reactor sludge by performing polymerase chain reaction–denaturing gradient gel electrophoresis (PCR-DGGE)

Changing Patterns of SARS-CoV-2 Seroprevalence: A Snapshot among the General Population in Kuwait

We sought to assess pre-vaccination and post-vaccination seroprevalences of anti-SARS-CoV-2 antibodies in Kuwait and to compare antibody levels between vaccine types. In phase 1 (pre-vaccination period, n = 19,363), blood samples were collected before the launch of COVID-19 vaccination in Kuwait between 1 September and 31 December 2020. Blood samples for phase 2 (post-vaccination period, n = 4973) were collected between 1 September and 30 November 2021. We tested subjects for anti-SARS-CoV-2 antibodies using the DiaSorin LIAISON® SARS-CoV-2 IgM and Trimeric S IgG tests. In the pre-vaccination period, the prevalence of SARS-CoV-2 IgM and IgG was 14.50% (95% CI: 14.01–15.00) and 24.89% (95% CI: 24.29–25.50), respectively. The trend of seropositivity increased with age and was higher for females and non-Kuwaiti participants (p < 0.0001). Interestingly, seroprevalence was significantly higher for those who had received one dose of BNT162b2 (95.21%) than those who had received one dose of ChAdOx1-nCov-19 (92.86%). In addition, those who reported receiving two doses had higher seroprevalence, 96.25%, 95.86%, and 94.93% for ChA-dOx1-nCov-19/AstraZeneca, mix-and-match, and BNT162b2 recipients, respectively. After the second dose, median spike-specific responses showed no significant difference between ChAdOx1-nCov-19 and BNT162b2. Furthermore, statistical analysis showed no significant difference between median anti-trimeric S antibody levels of vaccinated individuals according to sex, age, or nationality (p > 0.05). In contrast, a negative correlation between age and anti-trimeric S IgG titers of BNT162b2-vaccinated subjects was observed (r = −0.062, p = 0.0009). Antibody levels decreased with time after vaccination with both vaccines. Our findings indicate that seroprevalence was very low during the pre-vaccination period (25%) in the general population and was greater than 95% in the vaccinated population in Kuwait. Furthermore, ChAdOx1-nCov-19 and BNT162b2 are effective in generating a similar humoral response

Changing Patterns of SARS-CoV-2 Seroprevalence: A Snapshot among the General Population in Kuwait

We sought to assess pre-vaccination and post-vaccination seroprevalences of anti-SARS-CoV-2 antibodies in Kuwait and to compare antibody levels between vaccine types. In phase 1 (pre-vaccination period, n = 19,363), blood samples were collected before the launch of COVID-19 vaccination in Kuwait between 1 September and 31 December 2020. Blood samples for phase 2 (post-vaccination period, n = 4973) were collected between 1 September and 30 November 2021. We tested subjects for anti-SARS-CoV-2 antibodies using the DiaSorin LIAISON® SARS-CoV-2 IgM and Trimeric S IgG tests. In the pre-vaccination period, the prevalence of SARS-CoV-2 IgM and IgG was 14.50% (95% CI: 14.01–15.00) and 24.89% (95% CI: 24.29–25.50), respectively. The trend of seropositivity increased with age and was higher for females and non-Kuwaiti participants (p p > 0.05). In contrast, a negative correlation between age and anti-trimeric S IgG titers of BNT162b2-vaccinated subjects was observed (r = −0.062, p = 0.0009). Antibody levels decreased with time after vaccination with both vaccines. Our findings indicate that seroprevalence was very low during the pre-vaccination period (25%) in the general population and was greater than 95% in the vaccinated population in Kuwait. Furthermore, ChAdOx1-nCov-19 and BNT162b2 are effective in generating a similar humoral response

The worldwide antibiotic resistance and prescribing in european children (ARPEC) point prevalence survey : Developing hospital-quality indicators of antibiotic prescribing for children

Objectives: Previously, web-based tools for cross-sectional antimicrobial point prevalence surveys (PPSs) have been used in adults to develop indicators of quality improvement. We aimed to determine the feasibility of developing similar quality indicators of improved antimicrobial prescribing focusing specifically on hospitalized neonates and children worldwide. Methods: A standardized antimicrobial PPS method was employed. Included were all inpatient children and neonates receiving an antimicrobial at 8:00 am on the day of the PPS. Denominators included the total number of inpatients. A web-based application was used for data entry, validation and reporting. We analysed 2012 data from 226 hospitals (H) in 41 countries (C) from Europe (174H; 24C), Africa (6H; 4C), Asia (25H; 8C), Australia (6H), Latin America (11H; 3C) and North America (4H). Results: Of 17 693 admissions, 6499 (36.7%) inpatients received at least one antimicrobial, but this varied considerably between wards and regions. Potential indicators included very high broad-spectrum antibiotic prescribing in children of mainly ceftriaxone (ranked first in Eastern Europe, 31.3%; Asia, 13.0%; Southern Europe, 9.8%), cefepime (ranked third in North America, 7.8%) and meropenem (ranked first in Latin America, 13.1%). The survey identified worryingly high use of critically important antibiotics for hospital-acquired infections in neonates (34.9%; range from 14.2% in Africa to 68.0% in Latin America) compared with children (28.3%; range from 14.5% in Africa to 48.9% in Latin America). Parenteral administration was very common among children in Asia (88%), Latin America (81%) and Europe (67%). Documentation of the reasons for antibiotic prescribing was lowest in Latin America (52%). Prolonged surgical prophylaxis rates ranged from 78% (Europe) to 84% (Latin America). Conclusions: Simple web-based PPS tools provide a feasible method to identify areas for improvement of antibiotic use, to set benchmarks and to monitor future interventions in hospitalized neonates and children. To our knowledge, this study has derived the first global quality indicators for antibiotic use in hospitalized neonates and children

SARS-CoV-2 vaccination modelling for safe surgery to save lives: data from an international prospective cohort study

Background: Preoperative SARS-CoV-2 vaccination could support safer elective surgery. Vaccine numbers are limited so this study aimed to inform their prioritization by modelling. Methods: The primary outcome was the number needed to vaccinate (NNV) to prevent one COVID-19-related death in 1 year. NNVs were based on postoperative SARS-CoV-2 rates and mortality in an international cohort study (surgical patients), and community SARS-CoV-2 incidence and case fatality data (general population). NNV estimates were stratified by age (18-49, 50-69, 70 or more years) and type of surgery. Best- and worst-case scenarios were used to describe uncertainty. Results: NNVs were more favourable in surgical patients than the general population. The most favourable NNVs were in patients aged 70 years or more needing cancer surgery (351; best case 196, worst case 816) or non-cancer surgery (733; best case 407, worst case 1664). Both exceeded the NNV in the general population (1840; best case 1196, worst case 3066). NNVs for surgical patients remained favourable at a range of SARS-CoV-2 incidence rates in sensitivity analysis modelling. Globally, prioritizing preoperative vaccination of patients needing elective surgery ahead of the general population could prevent an additional 58 687 (best case 115 007, worst case 20 177) COVID-19-related deaths in 1 year. Conclusion: As global roll out of SARS-CoV-2 vaccination proceeds, patients needing elective surgery should be prioritized ahead of the general population