Prevalence of antibiotic resistance genes in drinking water of the Kathmandu Valley, Nepal

Thakali, Ocean; Malla, Bikash; Raya, Sunayana; Sthapit, Niva; Sherchan, Samendra P.; Furukawa, Takashi; Sei, Kazunari; Sherchand, JB; Haramoto, Eiji

doi:10.1016/j.envc.2022.100527

Cited by 2 publications

(4 citation statements)

References 43 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In the ddPCR quantification method used in this study, the limit of quantification was around 1.2 genome copies/reaction, which is comparable to a previous study ( Cavé et al, 2016 ). A previous study by our group which quantified ARGs in drinking water samples from Kathmandu Valley using the qPCR technique reported the limit of quantification as 5 copies/reaction which may get influenced by the amplification efficiency and the inhibitory substances ( Thakali et al, 2022 ). Therefore, ddPCR can be suggested as a sensitive and specific quantitative analysis method usable in routine monitoring studies for ARGs in aquatic environments even when the monitoring targets are available in very low concentrations or inhibitory substances are present ( Ishii, 2020 ).…”

Section: Discussionmentioning

confidence: 99%

“…bla TEM , ermF, mecA , and tet (A) genes were detected from the middle and downstream samples of the Bagmati River flowing through the Kathmandu Valley, confirming the anthropogenic contribution ( Thakali et al, 2020 ). To date, there is only one study on the presence of ARGs in drinking water sources utilized in the Kathmandu Valley ( Thakali et al, 2022 ). Therefore, in this study, we evaluated the ARG concentrations in drinking water sources (surface water and groundwater) and environmental waters in the Kathmandu Valley using the droplet digital polymerase chain reaction (ddPCR) method.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Prevalence of antibiotic resistance genes in drinking and environmental water sources of the Kathmandu Valley, Nepal

et al. 2022

View full text Add to dashboard Cite

Antibiotic-resistant bacteria-associated infections are responsible for more than 1.2 million annual deaths worldwide. In low- and middle-income countries (LMICs), the consumption of antibiotics for human and veterinary uses is not regulated effectively. Overused and misused antibiotics can end up in aquatic environments, which may act as a conduit for antibiotic resistance dissemination. However, data on the prevalence of antibiotic resistance determinants in aquatic environments are still limited for LMICs. In this study, we evaluated the prevalence and concentration of antibiotic resistance genes (ARGs) in different drinking and environmental water sources collected from the Kathmandu Valley, Nepal, using droplet digital polymerase chain reaction to understand the current situation of ARG contamination. River water and shallow dug well water sources were the most contaminated with ARGs. Almost all samples contained sul1 (94%), and intI1 and tet(A) were detected in 83 and 60% of the samples, respectively. Maximum ARG concentration varied between 4.2 log10 copies/100 ml for mecA and 9.3 log10 copies/100 ml for sul1. Significant positive correlations were found between ARGs (r > 0.5, p < 0.01), except for mecA, qnrS, and vanA. As sul1 and intI1 were detected in almost all samples, the presence of these genes in a given sample may need to be considered as background antibiotic resistance in LMICs. Therefore, monitoring of ARGs, such as β-lactam ARGs, quinolone resistance genes, and vancomycin resistance genes, may provide a better picture of the antibiotic resistance determinants in aquatic environments of LMICs.

show abstract

Section: Discussionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Prevalence of antibiotic resistance genes in drinking and environmental water sources of the Kathmandu Valley, Nepal

et al. 2022

View full text Add to dashboard Cite

show abstract

“…Though not similar, a varying prevalence percentage of class 1 integrons has been well documented within multidrug-resistant E. coli from humans, 10,[23][24][25][26][27][28][29] animals, [29][30] and the environment. 7,[13][14][15] One possible reason for such high prevalence may be that integrons occur widely in Enterobacteriaceae family, and are strongly correlated with MDR. 8-9, 27-28,30 Also, their ability to freely move within and between species with the help of conjugative plasmids may also be a contributing factor.…”

Section: Discussionmentioning

confidence: 99%

“…In Nepal, few studies have reported the occurrence of Class 1 Integron in both clinical [11][12] as well as environmental isolates [13][14][15] ; which were mostly multiple antibiotic resistant isolates including MDR Salmonella spp 12 and extended-spectrum β-lactamase producing (ESBL) E. coli. 11 Class 1 integron was reported only in bacteria of clinical origin 12 when compared to environmental isolates in Nepal.…”

Section: Introductionmentioning

confidence: 99%

Prevalence of Class 1 integron in disease-causing carbapenem-resistantEscherichia coliin a tertiary hospital in Kathmandu, Nepal

Thapa,

Shrestha,

Shrestha

et al. 2024

Preprint

View full text Add to dashboard Cite

BackgroundHigh prevalence of carbapenem resistance genes have been abundantly reported within clinicalE. coliin Nepal but their co-prevalence with class-1 integron is poorly documented. These Class I Integrons play pivotal role in evolution and spread of antimicrobial resistance (AMR). Therefore, it is necessary to highlight their epidemiological significance, so this study determined the prevalence of Class 1 integrons within Carbapenem resistanceEscherichia coli(CREc) population.MethodsFifty-two clinicalE. coliwith confirmed resistance to Meropenem were collected between January 2020–April 2022 in Kathmandu Model Hospital, and undergone antimicrobial susceptibility testing for 11 antimicrobial classes. Carbapenemase production was confirmed by eCIM and mCIM methods. Presence of Class I integron and carbapenemase genes,blaNDM-1,blaKPC,blaIMP,blaVIM,blaOXA-23,blaOXA-48, was confirmed by PCR method.ResultsThe result revealed 92.3% (n=48/52) of the isolates harboredintI1gene. Among integron-positive population, 97.9% (n=47/48) were carbapenemase producers which were further identified as metallo β-lactamase (MBL) producers (82.9%, n=39/47) and serine β-lactamase (SBL) producer (17%, n=8/47). Carbapenemase geneblaNDM-1(79.2%, n=38/48) was highly prevalent within integron-positive isolates, followed byblaOXA-23(62.5%, n=30/48) andblaOXA-48(54.2%, n=26/48). All integron-positive CREc isolates were resistant to minimum 16 antibiotics tested, but were susceptible to Colistin, Polymixin B, and Tigecycline.ConclusionIn conclusion, Class 1 integrons were highly prevalent within clinical CREc in Nepal, and their co-prevalence with other CRE gene is concerning due to possibility of wider spread. Therefore, an in-depth genomic analysis of Class 1 integrons is needed to understand the integron mediated AMR in high risk clones like CREc and inform intervention measures to stop spread of such pathogens.

show abstract

Prevalence of antibiotic resistance genes in drinking water of the Kathmandu Valley, Nepal

Cited by 2 publications

References 43 publications

Prevalence of antibiotic resistance genes in drinking and environmental water sources of the Kathmandu Valley, Nepal

Prevalence of antibiotic resistance genes in drinking and environmental water sources of the Kathmandu Valley, Nepal

Prevalence of Class 1 integron in disease-causing carbapenem-resistantEscherichia coliin a tertiary hospital in Kathmandu, Nepal

Contact Info

Product

Resources

About