Wastewater-based surveillance of COVID-19 and removal of SARS-CoV-2 RNA across a major wastewater treatment plant in San Antonio, Texas

Wastewater-based epidemiology (WBE) targeting SARS-CoV-2 RNA detection in municipal wastewater is considered a valuable tool for COVID-19 surveillance in a community. However, the persistence and removal of SARS-CoV-2 RNA in wastewater treatment plants (WWTPs) have not been well investigated. This study is aimed at detecting SARS-CoV-2 RNA in wastewater to correlate viral concentrations with clinical COVID-19 cases in the sewershed and determine whether the SARS-CoV-2 genetic material is detectable after treatment. Raw influent, primary effluent (after primary clarification), secondary effluent (after activated sludge treatment), and final effluent (after chlorination) samples were collected two times a week from the largest WWTP in San Antonio (Texas) during April to November 2021 and analyzed for SARS-CoV-2 RNA (N1 and N2 genes) concentrations using the reverse transcription droplet digital polymerase chain reaction (RT-ddPCR). SARS-CoV-2 RNA was detected in 98.5% (n = 34 weeks) of the raw influent samples and anticipated the trends of the COVID-19 outbreak. Furthermore, a higher correlation between viral concentrations and COVID-19 cases was observed for two days a week sampling frequency (ρ = 0.75, p <0.001) than one day per week (ρ = 0.60, p <0.001). Despite the high SARS-CoV-2 RNA concentrations in raw sewage, a significant amount of viral RNA was removed at primary and secondary clarifiers (removal efficiencies were 54% and 94%, respectively) and was undetectable in final effluents. These results demonstrate the performance of the WWTP in reducing the SARS-CoV-2 RNA concentration and further highlight the role of tertiary treatment and chlorination in eliminating SARS-CoV-2 RNA in receiving waters. © 2023 RSC.

Assessment of Concentration, Recovery, and Normalization of SARS-CoV-2 RNA from Two Wastewater Treatment Plants in Texas and Correlation with COVID-19 Cases in the Community

The purpose of this study was to conduct a correlative assessment of SARS-CoV-2 RNA concentrations in wastewater with COVID-19 cases and a systematic evaluation of the effect of using different virus concentration methods and recovery and normalization approaches. We measured SARS-CoV-2 RNA concentrations at two different wastewater treatment plants (WWTPs) in the Bexar County of Texas from October 2020 to May 2021 (32 weeks) using reverse transcription droplet digital PCR (RT-ddPCR). We evaluated three different adsorption-extraction (AE) based virus concentration methods (acidification, addition of MgCl2, or without any pretreatment) using bovine coronavirus (BCoV) as surrogate virus and observed that the direct AE method showed the highest mean recovery. COVID-19 cases were correlated significantly with SARS-CoV-2 N1 concentrations in Salitrillo (rho = 0.75, p < 0.001) and Martinez II (rho = 0.68, p < 0.001) WWTPs, but normalizing to a spiked recovery control (BCoV) or a fecal marker (HF183) reduced correlations for both treatment plants. The results generated in this 32-week monitoring study will enable researchers to prioritize the virus recovery method and subsequent correlation studies for wastewater surveillance.

Thyroid dysfunction following vaccination with COVID-19 vaccines: a basic review of the preliminary evidence.

PURPOSE: The safety and efficacy of the several types of COVID-19 vaccines, including mRNA-based, viral vector-based, and inactivated vaccines, have been approved by WHO. The vaccines can confer protection against severe SARS-CoV-2 infection through induction of the anti-spike protein neutralizing antibodies. However, SARS-CoV-2 vaccines have been associated with very rare complications, such as thyroid disorders. This review was conducted to highlight main features of thyroid abnormalities following COVID-19 vaccination. METHODS: A comprehensive search within electronic databases was performed to collect reports of thyroid disorders after vaccination with COVID-19 vaccines. RESULTS: Among 83 reported cases including in this review, the most cases of thyroid abnormalities were observed after vaccination with mRNA-based vaccines (68.7%), followed by viral vector vaccines (15.7%) and 14.5% cases following inactivated vaccines. Subacute thyroiditis (SAT) was the most common COVID-19 vaccination-related thyroid disease, accounting for 60.2% of all cases, followed by Graves' disease (GD) with 25.3%. Moreover, some cases with focal painful thyroiditis (3.6%), silent thyroiditis (3.6%), concurrent GD and SAT (2.4%), thyroid eye disease (1.2%), overt hypothyroidism (1.2%), atypical subacute thyroiditis (1.2%), and painless thyroiditis with TPP (1.2%) were also reported. Overall, in 58.0% of SAT cases and in 61.9% of GD cases, the onset of the symptoms occurred following the first vaccine dose with a median of 10.0 days (ranged: 3-21 days) and 10.0 days (ranged: 1-60 days) after vaccination, respectively. Moreover, 40.0% of SAT patients and 38.1% of GD patients developed the symptoms after the second dose with a median of 10.5 days (ranged: 0.5-37 days) and 14.0 days (ranged: 2-35 days) after vaccination, respectively. CONCLUSION: Fortunately, almost all cases with COVID-19 vaccination-associated thyroid dysfunctions had a favorable outcome following therapy. The benefits of COVID-19 vaccinations in terms of terminating the pandemic and/or reducing mortality rates can exceed any risk of infrequent complications such as a transient thyroid malfunction.

Health care policy makers' response to COVID-19 pandemic;pros and cons of "flattening the curve" from the "selective pressure" point of view: a review

COVID-19, a respiratory infection caused by the virus SARS-CoV-2, causes a variety of symptoms in infected people. We have recently addressed our concerns over unintentional "Directed Accelerated Evolution" of the SARS-CoV-2 and introduced a modified treatment method for ARDS associated with COVID-19. COVID-19 outbreak could last for a long time in communities. Due to growing requests for medical equipment such as ventilators and ICU beds, "flattening the epidemic curve" has been considered as an effective strategy to adjust the level of health care demand to potential capacity of the system. In this paper, we compare possible outcomes of "Without Precaution" and "With Precaution" epidemic models. When there are no precautions, a higher number of people would be infected. RNA viruses such as SARS-CoV-2 have extremely high mutation rates. Accordingly, the combination of a higher number of infected people and any effort for inactivation of the viruses is expected to exert a strong selective pressure on SARS-CoV-2 that can lead to more mutations. These mutations can be either pathogenicity attenuating mutations (PAMs) or pathogenicity promoting mutations (PPMs). On the other hand, when flattening strategy is used, the number of infected people will be lower than the previous model, but both type of mutations may occur, although with lower frequency. Although the occurrence of PAMs helps the development of herd immunity, possible occurrence of PPMs needs serious tracking, especially in patients with severe COVID-19, to prevent new endemic with more virulent mutant viruses.

A contact tracing prospective cohort retrieving epidemiological facts on sars-cov-2 transmission aspects: A serological analysis in an iranian community

Background: The spread of the novel coronavirus seems mysterious enough to make us double-check the indices being used to predict its transmission. In this study, serological analysis was performed to assess some metric and epidemiological aspects of the infection and its transmissibility among people in contact with SARA-CoV-2 patients. Material and Methods: A total of 453 contacts of 40 COVID-19 patients entered this contact tracing prospective cohort study. Accordingly, SARS-CoV-2 patients were diagnosed by the real-time polymerase chain reaction testing of nasopharyngeal samples. The infectiousness history was detected by the serological testing of IgG and IgM. Trained expert team completed two questionnaires, and blood samples were taken by experts in a laboratory. Data were analyzed using SPSS V21.0 and R software. Results: The mean ages of the SARS-CoV-2 patients and the contacts were 53.0±18.2 and 30.8±19.3 years, respectively. The overall R0 of the infection was 2.58. Household and non-household secondary attack rates (SAR) were 20% (95%CI;12.7–27.3) and 11.3% (95%CI;6.1-16.5), respectively. The transmission probability of each contact was 0.0205, and the serial interval was 6.4±4.6 (95% CI;5.2–7.6) days. The SAR was higher among the contacts who were exposed to asymptomatic primary cases (28%, 95%CI;10-46%) than (13.8%, 95%CI;9.4-18.2) among those exposed to symptomatic patients. Conclusions: It is concluded that the herd immunity of 60 to 65% is needed in human communities, based on the amount of R0 estimated in our survey. The findings demonstrated the amount of the reduction in infection R0, which is predicted based on both clinical and public health interventions. © The Author(s) 2021;All rights reserved.

Therapeutic potential of ginger against COVID-19: Is there enough evidence?

In addition to the respiratory system, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) strikes other systems, including the digestive, circulatory, urogenital, and even the central nervous system, as its receptor angiotensin-converting enzyme 2 (ACE2) is expressed in various organs, such as lungs, intestine, heart, esophagus, kidneys, bladder, testis, liver, and brain. Different mechanisms, in particular, massive virus replication, extensive apoptosis and necrosis of the lung-related epithelial and endothelial cells, vascular leakage, hyper-inflammatory responses, overproduction of pro-inflammatory mediators, cytokine storm, oxidative stress, downregulation of ACE2, and impairment of the renin-angiotensin system contribute to the COVID-19 pathogenesis. Currently, COVID-19 is a global pandemic with no specific anti-viral treatment. The favorable capabilities of the ginger were indicated in patients suffering from osteoarthritis, neurodegenerative disorders, rheumatoid arthritis, type 2 diabetes, respiratory distress, liver diseases and primary dysmenorrheal. Ginger or its compounds exhibited strong anti-inflammatory and anti-oxidative influences in numerous animal models. This review provides evidence regarding the potential effects of ginger against SARS-CoV-2 infection and highlights its antiviral, anti-inflammatory, antioxidative, and immunomodulatory impacts in an attempt to consider this plant as an alternative therapeutic agent for COVID-19 treatment. © 2021 Beijing University of Chinese Medicine