Prevalence of MDR organism (MDRO) carriage in children and their household members in Siem Reap Province, Cambodia

Plugging the leaks: antibiotic resistance at human-animal interfaces in low-resource settings

Antibiotic resistance is one of the greatest public health challenges of our time. International efforts to curb resistance have largely focused on drug development and limiting unnecessary antibiotic use. However, in areas where water, sanitation, and hygiene infrastructure is lacking, we propose that bacterial flow between humans and animals can exacerbate the emergence and spread of resistant pathogens. Here, we describe the consequences of poor environmental controls by comparing mobile resistance elements among Escherichia coli recovered from humans and meat in Cambodia, a middle-income country with substantial human-animal connectivity and unregulated antibiotic use. We identified identical mobile resistance elements and a conserved transposon region that were widely dispersed in both humans and animals, a phenomenon rarely observed in high-income settings. Our findings indicate that plugging leaks at human-animal interfaces should be a critical part of addressing antibiotic resistance in low- and especially middle-income countries.

Whole genome sequencing of multidrug resistant Enterobacterales identified in children and their household members within Siem Reap, Cambodia

Objectives

To explore the association of recent hospitalization and asymptomatic carriage of multidrug-resistant Enterobacterales (MDRE) and determine the prevailing strains and antibiotic resistance genes in Siem Reap, Cambodia using WGS.

Methods

In this cross-sectional study, faecal samples were collected from two arms: a hospital-associated arm consisted of recently hospitalized children (2-14 years), with their family members; and a community-associated arm comprising children in the matching age group and their family members with no recent hospitalization. Forty-two families in each study arm were recruited, with 376 enrolled participants (169 adults and 207 children) and 290 stool specimens collected from participants. The DNA of ESBL- and carbapenemase-producing Enterobacterales cultured from the faecal samples was subject to WGS on the Illumina NovaSeq platform.

Results

Of the 290 stool specimens, 277 Escherichia coli isolates and 130 Klebsiella spp. were identified on CHROMagar ESBL and KPC plates. The DNA of 276 E. coli (one isolate failed quality control test), 89 Klebsiella pneumoniae, 40 Klebsiella quasipneumoniae and 1 Klebsiella variicola was sequenced. CTX-M-15 was the most common ESBL gene found in E. coli (n = 104, 38%), K. pneumoniae (n = 50, 56%) and K. quasipneumoniae (n = 16, 40%). The prevalence of bacterial lineages and ESBL genes was not associated with any specific arm.

Conclusions

Our results demonstrate that MDRE is likely to be endemic within the Siem Reap community. ESBL genes, specifically bla_CTX-M, can be found in almost all E. coli commensals, indicating that these genes are continuously propagated in the community through various unknown channels at present.

Detection of maternal transmission of resistant Gram-negative bacteria in a Cambodian hospital setting

Infection with Extended-spectrum beta-lactamase -producing Enterobacterales (ESBL-E) is common in infants and leads to increased intensive care unit admission and mortality, but the role of maternal transmission in colonization of infants is unclear. Using paired isolates from 50 pairs of mothers and neonates admitted to a Cambodian hospital, we investigated antimicrobial resistance in Escherichia coli and Klebsiella pneumoniae using whole genome sequencing. We detected a wide variety of ESBL-E genes present in this population along with high levels of multidrug resistance. From 21 pairs where the same organism was present in both mother and neonate, we identified eight pairs with identical or near-identical isolates from both individuals suggestive of transmission at or around birth, including a pair with transmission of multiple strains. We found no evidence for transmission of plasmids only from mother to infant. This suggests vertical transmission outside hospitals as a common cause of ESBL-E colonization in neonates.

Epidemiology of Extended-Spectrum Beta-Lactamase and Carbapenemase-Producing Enterobacterales in the Greater Mekong Subregion: A Systematic-Review and Meta-Analysis of Risk Factors Associated With Extended-Spectrum Beta-Lactamase and Carbapenemase Isolation

Background: Despite the rapid spread of extended-spectrum beta-lactamase (ESBL) producing-Enterobacterales (ESBL-E) and carbapenemase-producing Enterobacterales (CPE), little is known about the extent of their prevalence in the Greater Mekong Subregion (GMS). In this systematic review, we aimed to determine the epidemiology of ESBL-E and CPE in clinically significant Enterobacterales: Escherichia coli and Klebsiella pneumoniae from the GMS (comprising of Cambodia, Laos, Myanmar, Thailand, Vietnam and Yunnan province and Guangxi Zhuang region of China). Methods: Following a list of search terms adapted to subject headings, we systematically searched databases: Medline, EMBASE, Scopus and Web of Science for articles published on and before October 20th, 2020. The search string consisted of the bacterial names, methods involved in detecting drug-resistance phenotype and genotype, GMS countries, and ESBL and carbapenemase detection as the outcomes. Meta-analyses of the association between the isolation of ESBL from human clinical and non-clinical specimens were performed using the "METAN" function in STATA 14. Results: One hundred and thirty-nine studies were included from a total of 1,513 identified studies. Despite the heterogeneity in study methods, analyzing the prevalence proportions on log-linear model scale for ESBL producing-E. coli showed a trend that increased by 13.2% (95%CI: 6.1-20.2) in clinical blood specimens, 8.1% (95%CI: 1.7-14.4) in all clinical specimens and 17.7% (95%CI: 4.9-30.4) increase in carriage specimens. Under the log-linear model assumption, no significant trend over time was found for ESBL producing K. pneumoniae and ESBL-E specimens. CPE was reported in clinical studies and carriage studies past 2010, however a trend could not be determined because of the small dataset. Twelve studies were included in the meta-analysis of risk factors associated with isolation of ESBL. Recent antibiotic exposure was the most studied variable and showed a significant positive association with ESBL-E isolation (pooled OR: 2.9, 95%CI: 2.3-3.8) followed by chronic kidney disease (pooled OR: 4.7, 95%CI: 1.8-11.9), and other co-morbidities (pooled OR: 1.6, 95%CI: 1.2-2.9). Conclusion: Data from GMS is heterogeneous with significant data-gaps, especially in community settings from Laos, Myanmar, Cambodia and Yunnan and Guangxi provinces of China. Collaborative work standardizing the methodology of studies will aid in better monitoring, surveillance and evaluation of interventions across the GMS.