Browsing by Author "Joshi, Madhvi"

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), a neoteric virus belonging to the beta coronavirus class has created a global health concern, responsible for an outbreak of severe acute respiratory illness, the COVID-19 pandemic. Infected hosts exhibit diverse clinical features, ranging from asymptomatic to severe symptoms in their genital organs, respiratory, digestive, and circulatory systems. Considering the high transmissibility (R0: ≤6.0) compared to Middle East respiratory syndrome coronavirus (MERS-CoV) and SARS-CoV, the quest for the clinical development of suitable antiviral nanotherapeutics (NTPs) is incessant. We are presenting a systematic review of the literature published between 2003 and 2020 to validate the hypothesis that the pharmacokinetics, collateral acute/chronic side effects of nano drugs and spike proteins arrangement of coronaviruses can revolutionize the therapeutic approach to cure COVID-19. Our aim is also to critically assess the slow release kinetics and specific target site chemical synthesis influenced competence of NTPs and nanotoxicity based antiviral actions, which are commonly exploited in the synthesis of modulated nanomedicines. The pathogenesis of novel virulent pathogens at the cellular and molecular levels are also considered, which is of utmost importance to characterize the emerging nano-drug agents as diagnostics or therapeutics or viral entry inhibitors. Such types of approaches trigger the scientists and policymakers in the development of a conceptual framework of nano-biotechnology by linking nanoscience and virology to present a smart molecular diagnosis/treatment for pandemic viral infections.

In the initial pandemic phase, effluents from wastewater treatment facilities were reported mostly free from Severe Acute Respiratory Coronavirus 2 (SARS-CoV-2) RNA, and thus conventional wastewater treatments were generally considered effective. However, there is a lack of first-hand data on i) comparative efficacy of various treatment processes for SARS-CoV-2 RNA removal; and ii) temporal variations in the removal efficacy of a given treatment process in the backdrop of active COVID-19 cases. This work provides a comparative account of the removal efficacy of conventional activated sludge (CAS) and root zone treatments (RZT) based on weekly wastewater surveillance data, consisting of forty-four samples, during a two-month period. The average genome concentration was higher in the inlets of CAS-based wastewater treatment plant (WWTP) in the Sargasan ward (1.25 × 10³ copies/ L), than that of RZT-based WWTP (7.07 × 10² copies/ L) in an academic institution campus of Gandhinagar, Gujarat, India. ORF 1ab and S genes appeared to be more sensitive to treatment i.e., significantly reduced (p < 0.05) than N genes (p > 0.05). CAS treatment exhibited better RNA removal efficacy (p = 0.014) than RZT (p = 0.032). Multivariate analyses suggested that the effective genome concentration should be calculated based on the presence/absence of multiple genes. The present study stresses that treated effluents are not always free from SARS-CoV-2 RNA, and the removal efficacy of a given WWTP is prone to exhibit temporal variability owing to variations in active COVID-19 cases in the vicinity and genetic material accumulation over the time. Disinfection seems less effective than the adsorption and coagulation processes for SARS-CoV-2 removal. Results stress the need for further research on mechanistic insight on SARS-CoV-2 removal through various treatment processes taking solid–liquid partitioning into account.

We made the first ever successful effort in India to detect the genetic material of SARS-CoV-2 viruses to understand the capability and application of wastewater-based epidemiology (WBE) surveillance in India. Sampling was carried out on 8 and 27 May 2020 at the Old Pirana Waste Water Treatment Plant (WWTP) at Ahmedabad, Gujarat that receives effluent from Civil Hospital treating COVID-19 patients. All three, i.e. ORF1ab, N and S genes of SARS-CoV-2, were found in the influent with no genes detected in effluent collected on 8 and 27 May 2020. Increase in SARS-CoV-2 genetic loading in the wastewater between 8 and 27 May 2020 samples concurred with corresponding increase in the number of active COVID-19 patients in the city. The number of gene copies was comparable to that reported in untreated wastewaters of Australia, China and Turkey and lower than that of the USA, France and Spain. However, temporal changes in SARS-CoV-2 RNA concentrations need to be substantiated further from the perspectives of daily and short-term changes of SARS-CoV-2 in wastewater through long-term monitoring. The study results SARS-CoV-2 will assist concerned authorities and policymakers to formulate and/or upgrade COVID-19 surveillance to have a more explicit picture of the pandemic curve. While infectivity of SARS-CoV-2 through the excreted viral genetic material in the aquatic environment is still being debated, the presence and detection of genes in wastewater systems makes a strong case for the environmental surveillance of the COVID-19 pandemic.

Wastewater-based genomic surveillance can identify a huge majority of variants shed by the infected individuals within a population, which goes beyond genomic surveillance based on clinical samples (i.e., symptomatic patients only). We analyzed four samples to detect key mutations in the SARS-CoV-2 genome and track circulating variants in Ahmedabad during the first wave (Sep/Nov 2020) and before the second wave (in Feb 2021) of COVID-19 in India. The analysis identified a total of 34 mutations in the spike protein across samples categorized into 23 types. The spike protein mutations were linked to the VOC-21APR-02; B.1.617.2 lineage (Delta variant) with 57% frequency in wastewater samples of Feb 2021. The key spike protein mutations were T19R, L452R, T478K, D614G, & P681R and deletions at 22029 (6 bp), 28248 (6 bp), & 28271 (1 bp). Interestingly, these mutations were not seen in the samples from Sep/Nov 2020 but did appear before the massive second wave of COVID-19 cases, which in India started in early April 2021. In fact, genetic traces of the Delta variant were found in samples of early Feb 2021, more than a month before the first clinically confirmed case of this in March 2021 in Ahmedabad, Gujarat. The present work describes the circulating of SARS-CoV-2 variants in Ahmedabad and confirms the consequential value of wastewater surveillance for the early detection of variants of concerns (VOCs). Such monitoring must be included as a major component of future health protection systems.

Globally, environmental pollution by plastic waste has become a severe ecological and social problem worldwide. The present study aimed to analyse the bacterial community structure and functional potential of the landfill site using high throughput shotgun metagenomic approach to understand plastic degrading capabilities present in the municipal solid waste (MSW) dumping site. In this study, soil, leachate and compost samples were collected from various locations (height and depth) of the Pirana landfill site in Ahmedabad city Gujarat, India. In total 30 phyla, 58 class, 125 order, 278 families, 793 genera, and 2468 species were predicted. The most dominant phyla detected were Proteobacteria, Bacteroidetes, Firmicutes, and Actinobacteria in the soil and compost samples. Whereas, in leachate samples, the predominant phyla belonged to Firmicutes (54.24%) followed by Actinobacteria (43.67%) and Proteobacteria (1.02%). The functional profiling revealed the presence of enzymatic groups and pathways involved in biodegradation of xenobiotics. The results also demonstrated the presence of potential genes that is associated with the biodegradation of different types of plastics such as polyethylene (PE), polyethylene terephthalate (PET), and polystyrene (PS). Present study extablishes the relationship between microbial community structure and rich sources of gene pool, which are actively involved in biodegradation of plastic waste in landfill sites.

There is an increasing trend of developing various low-cost biogenic sorbents for the efficient and economical removal of noxious metals . Curry leaf powder (CLP), a promising non-toxic biosorbent containing several bioactive compounds was prepared by the pulverization of the dried leaves for the effective removal of Lead (Pb) and Cadmium (Cd). Various batch sorption experiments were carried out under constant temperature (25 °C), different pH (4.5–10.5), initial concentrations (50–200 mg L⁻¹), adsorbent dosages (0.10–0.40 g) and contact times (0–60 min) to understand the optimum experimental conditions and simultaneously evaluate the adsorption isotherms and removal kinetics of CLP. Adsorption equilibrium was established in less than an hour interval (50 min). The pseudo-equilibrium process was best described by the pseudo-second-order kinetic (R² ≥ 0.99), Freundlich and Langmuir isotherm model (R² ≥ 0.94). The removal rate of Pb and Cd gradually increased (15.7 and 12.7 mg g⁻¹ for Pb and Cd) at 100 mg L⁻¹ of initial concentration till 60 min of contact period in a single contaminant system, the effect was non-significant for multiple adsorbent dosage systems (p > 0.05; t-test) though. The regeneration potential of the exhausted biosorbent was excellent upto 5 cycles with the better efficiency observed for Pb. The obtained results explicitly validated the probable utilization of CLP as a promising green adsorbent for metal removal . Future study may highlight the decontamination aspects of emerging contaminants with such green bio sorbents in large scale as well as mimicing the stomach conditions.

Antimicrobial resistance (AMR) poses a critical threat to global public health, necessitating the development of novel strategies. AMR occurs when bacteria, viruses, fungi, and parasites evolve to resist antimicrobial drugs, making infections difficult to treat and increasing the risk of disease spread, severe illness, and death. Over 70% of infection-causing microorganisms are estimated to be resistant to one or several antimicrobial drugs. AMR mechanisms include efflux pumps, target modifications (e.g., mutations in penicillin-binding proteins (PBPs), ribosomal subunits, or DNA gyrase), drug hydrolysis by enzymes (e.g., β-lactamase), and membrane alterations that reduce the antibiotic's binding affinity and entry. Microbes also resist antimicrobials through peptidoglycan precursor modification, ribosomal subunit methylation, and alterations in metabolic enzymes. Rapid development of new strategies is essential to curb the spread of AMR and microbial infections. Nanomedicines, with their small size and unique physicochemical properties, offer a promising solution by overcoming drug resistance mechanisms such as reduced drug uptake, increased efflux, biofilm formation, and intracellular bacterial persistence. They enhance the therapeutic efficacy of antimicrobial agents, reduce toxicity, and tackle microbial resistance effectively. Various nanomaterials, including polymeric-based, lipid-based, metal nanoparticles, carbohydrate-derived, nucleic acid-based, and hydrogels, provide efficient solutions for AMR. This review addresses the epidemiology of microbial resistance, outlines key resistance mechanisms, and explores how nanomedicines overcome these barriers. In conclusion, nanomaterials represent a versatile and powerful approach to combating the current antimicrobial crisis.

We evaluate the imprints of urbanization, landuse and lifestyle on the prevalence and provenance of antibiotic resistance in the tropical rivers of Sri Lanka (Kelani and Gin) and India (Sabarmati, and Brahmaputra River). The prevalence of E. coli in the Kelani, Sabarmati, and Brahmaputra Rivers was in the range of 10–27, 267–76,600, and <50 CFU ml⁻¹ respectively. Isolated E. coli colonies were subjected to six antibiotics to assess their resistance. We found higher resistance to old generation antibiotics like tetracycline (TC), and sulfamethoxazole (ST) transcends the resistance for fluoroquinolones like norfloxacin (NFX), ciprofloxacin (CIP), and levofloxacin (LVX). Interestingly, both Indian rivers had exhibited relatively higher resistance to TC and ST than the Kelani river or Gin River, implying that the Sri Lankan situation is relatively less critical. At genetic level the resistance for β-lactams, fluoroquinolones and sulphonamides, were detected in many samples, as reported globally. While the resistance genes for aac-(6’)-1b-cr, qnrS and sul1 were detected in both Sri Lankan and Indian Rivers, blaTEM and ampC were specific to the Indian Rivers only. Decoupling of the prevalence of metal contamination and antibiotic resistance has been noticed in India and Sri Lanka. Study implies that urbanization, landuse, and lifestyle (ULL) are the three most critical factors governing multidrug resistance (MDR) and fecal contamination.

Wastewater-based epidemiology (WBE) is a promising approach to understand the actual prevalence of COVID-19 disease at the community level. Different studies have cited the presence of SARS-CoV-2 in wastewater samples. In the present study, eighteen influent wastewater samples from different sewage treatment plants and pumping stations (5 samples from Vadodara city, 4 from Gandhinagar, and 9 from Ahmedabad city) were collected and analyzed for the presence of SARS-CoV-2 RNA in Gujarat state, India. The results showed the highest SARS-CoV-2 effective gene concentration in Vadodara (3078 copies/L), followed by Ahmedabad (2968 copies/L) and Gandhinagar (354 copies/L). On comparing the virus gene concentration in wastewater samples, the SARS-CoV-2 genetic material exhibited a positive relationship with the number of confirmed and active cases in in all three cities. However, a minor variation in SARS-CoV-2 effective gene concentration was seen between Vadodara and Ahmedabad despite a >2.5 and >1.5 folds differences in the cumulative number of confirmed and active cases, respectively. This may occur primarily due to the greater test positivity ratio in Vadodara (3.30%) than Ahmedabad (1.40%) and might be the higher number of asymptomatic patients in Vadodara. The study confirms the potential of the WBE that can be used at a large scale around the globe for better dealing with the pandemic situation.

COVID-19 positive patients can egest live SARS-CoV-2 virus and viral genome fragments through faecal matter and urine, raising concerns about viral transmission through the faecal-oral route and/or contaminated aerosolized water. These concerns are amplified in many low- and middle-income countries, where raw sewage is often discharged into surface waterways and open defecation is common. Nonetheless, there has been no evidence of COVID-19 transmission via ambient urban water, and the virus viability in such aquatic matrices is believed to be minimal and not a matter of concern. In this manuscript, we attempt to discern the presence of SARS-CoV-2 genetic material (ORF-1ab, N and S genes) in the urban water (lakes, rivers, and drains) of the two Indian cities viz., Ahmedabad (AMD), in western India with 9 wastewater treatment plants (WWTPs) and Guwahati (GHY), in the north-east of the country with no such treatment facilities. The present study was carried out to establish the applicability of environmental water surveillance (E-wat-Surveillance) of COVID-19 as a potential tool for public health monitoring at the community level. 25.8% and 20% of the urban water samples had detectable SARS-CoV-2 RNA load in AMD and GHY, respectively. N-gene > S-gene > ORF-1ab-gene were readily detected in the urban surface water of AMD, whereas no such observable trend was noticed in the case of GHY. The high concentrations of SARS-CoV-2 genes (e.g., ORF-1ab; 800 copies/L for Sabarmati River, AMD and S-gene; 565 copies/L for Bharalu urban river, GHY) found in urban waters suggest that WWTPs do not always completely remove the virus genetic material and that E-wat-Surveillance of COVID-19 in cities/rural areas with poor sanitation is possible.

Wastewater-based Epidemiological (WBE) surveillance offers a promising approach to assess the pandemic situation covering pre-symptomatic and asymptomatic cases in highly populated area under limited clinical tests. In the present study, we analyzed SARS-CoV-2 RNA in the influent wastewater samples (n = 43) from four wastewater treatment plants (WWTPs) in Gandhinagar, India, during August 7th to September 30th, 2020. A total of 40 samples out of 43 were found positive i.e. having at least two genes of SARS-CoV-2. The average Ct values for S, N, and ORF 1 ab genes were 32.66, 33.03, and 33.95, respectively. Monthly variation depicted a substantial rise in the average copies of N (~120%) and ORF 1 ab (~38%) genes in the month of September as compared to August, while S-gene copies declined by 58% in September 2020. The SARS-CoV-2 genome concentration was higher in the month of September (~924.5 copies/L) than August (~897.5 copies/L), corresponding to a ~2.2-fold rise in the number of confirmed cases during the study period. Further, the percentage change in genome concentration level on a particular date was found in the lead of 1–2 weeks of time with respect to the official confirmed cases registered based on clinical tests on a temporal scale. The results profoundly unravel the potential of WBE surveillance to predict the fluctuation of COVID-19 cases to provide an early warning. Our study explicitly suggests that it is the need of hour that the wastewater surveillance must be included as an integral part of COVID-19 pandemic monitoring which can not only help the water authorities to identify the hotspots within a city but can provide up to 2 weeks of time lead for better tuning the management interventions.

Following the proven concept, capabilities, and limitations of detecting the RNA of Severe Acute Respiratory Coronavirus 2 (SARS-CoV-2) in wastewater, it is pertinent to understand the utility of wastewater surveillance data on various scale. In the present work, we put forward the first wastewater surveillance-based city zonation for effective COVID-19 pandemic preparedness. A three-month data of Surveillance of Wastewater for Early Epidemic Prediction (SWEEP) was generated for the world heritage city of Ahmedabad, Gujarat, India. In this expedition, 116 wastewater samples were analyzed to detect SARS-CoV-2 RNA, from September 3rd to November 26th, 2020. A total of 111 samples were detected with at least two out of three SARS-CoV-2 genes (N, ORF 1ab, and S). Monthly variation depicted a significant decline in all three gene copies in October compared to September 2020, followed by a sharp increment in November 2020. Correspondingly, the descending order of average effective gene concentration was: November (~10,729 copies/L) > September (~3047 copies/L) > October (~454 copies/L). Monthly variation of SARS-CoV-2 RNA in the wastewater samples may be ascribed to a decline of 20.48% in the total number of active cases in October 2020 and a rise of 1.82% in November 2020. Also, the monthly recovered new cases were found to be 16.61, 20.03, and 15.58% in September, October, and November 2020, respectively. The percentage change in the gene concentration was observed in the lead of 1–2 weeks with respect to the percentage change in the provisional figures of confirmed cases. SWEEP data-based city zonation was matched with the heat map of the overall COVID-19 infected population in Ahmedabad city, and month-wise effective gene concentration variations are shown on the map. The results expound on the potential of WBE surveillance of COVID-19 as a city zonation tool that can be meaningfully interpreted, predicted, and propagated for community preparedness through advanced identification of COVID-19 hotspots within a given city.