New APC research highlights implications of antibiotic use in human and veterinary medicine
A series of five research publications on Antimicrobial Resistance (AMR) by APC Microbiome Ireland, a world-leading SFI Research Centre, yields new data regarding the implications of antibiotic use in early life and the effects of antibiotics in standard dry cow therapy.
Lead author of these publications, Dr Dhrati Patangia, was recruited under the APC AMR PhD Fellowship programme funded by SFI in 2018.A paper published in the international scientific journal Microbiome provides evidence that early life exposure of infants to specific antibiotics could lead to multi-drug resistance. A second publication, in the journal Antibiotics, suggests that antibiotic use does not benefit standard dry cow therapy.
Dr Patangia is also lead author on two reviews in highly cited publications; one in the prestigious review journal Trends in Microbiology entitled ‘Vertical transfer of antibiotics and antibiotic resistant strains across the mother/baby axis’ which reviews the mechanisms of mother to infant transmission of antibiotics and antibiotic resistant strains. The second paper published in the journal Microbiology Open Reviews is entitled ‘Impact of antibiotics on the human microbiome and consequences for host health’ discusses the adverse effects of antibiotics on the gut microbiota and thus host health and suggests alternative approaches to antibiotic use.
Dr Patangia is a recent PhD graduate from the APC and School of Microbiology, University College Cork. While undertaking her PhD, she was based in Teagasc in Moorepark, Co Cork, building on the close collaborative relationship between UCC and Teagasc. Dr Patangia was supervised by Professor Catherine Stanton, APC co-Principal Investigator, and Professor Paul Ross, Director of APC, and has won several awards including best poster prize at the 2022 Dublin University Microbiological Society focused meeting.
Dr Patangia says “My interest in the microbiome started in India when I chose the topic for a research module as part of my Masters programme. I was delighted to discover the APC Antimicrobial Resistance PhD Fellowship programme which enabled me to target my PhD on my interest areas: the human microbiome, antibiotic resistance, and early life. While antibiotics provide lifesaving benefits, they come at the cost of the potential development of antimicrobial resistance which could result in a lack of effective medication in certain situations.”
APC Director Professor Paul Ross says “The goal of the APC Antimicrobial Resistance PhD Fellowship programme was to train a group of PhD students with specific research skills to create an expert cohort of AMR researchers. AMR is a huge global crises with an anticipated twofold surge in resistance to last-resort antibiotics by 2035, compared to 2005 levels according to the Organization for Economic Cooperation (source WHO).”
Professor Philip Nolan, Director General, Science Foundation Ireland, said: “SFI is committed to supporting research excellence to address the future challenges. Antimicrobial resistance is a growing global public health challenge, we congratulate APC and Dr Patangia in their recent scientific discoveries towards a better understanding of and solutions addressing antimicrobial resistance.”
Vice President for Research and Innovation at UCC Professor John F. Cryan says “UCC has a research focus on the challenges and opportunities that are shaping the future of our nation and the wider world. UCC scientists at APC are pioneering critical research to combat the global AMR crises through microbiome research.”
Teagasc Senior Principal Research Officer and APC PI Catherine Stanton says “There is no doubt that antibiotics are vital for the treatment of certain infections in infants. However, this study has shown that antibiotic exposure in early life has an immediate and persistent effect on the gut microbiome, highlighting the need for new alternatives/strategies to be developed and used where needed to restore the microbial ecosystem and maintain a healthy microenvironment, and reduce the use of prophylactic antibiotics during the crucial infancy stage.”
Review 1: Vertical transfer of antibiotics and antibiotic resistant strains across the mother/baby axis
Read on Trends in Microbiology | Cell Press: Vertical transfer of antibiotics and antibiotic resistant strains across the mother/baby axis - ScienceDirect
Despite the usage of antibiotics during pregnancy and infancy not many studies report the transfer of antibiotic resistance genes and antibiotics vertically, this review highlights the importance of studying transfer of antibiotic-resistance genes through vertical transfer. As the negative impact of antibiotic-resistant strains on the infant gut microbiota could result in drug-resistant infections which are difficult to treat.
Review 2: Impact of antibiotics on the human microbiome and consequences for host health
Antibiotic‐induced changes in microbial composition can have a negative impact on host health including reduced microbial diversity, changes in functional attributes of the microbiota, formation, and selection of antibiotic‐resistant strains making hosts more susceptible to infection with pathogens. This review discusses the adverse impacts of antibiotics on host health and microbiota.
Paper1: Microbiota and Resistome Analysis of Colostrum and Milk from Dairy Cows Treated with and without Dry Cow Therapies
This study investigated the effect of antibiotic use during dry cow therapy in cows and its impact on antibiotic resistance and microbiota development in colostrum and milk up to 6 months longitudinally. We observed a high relative abundance of antibiotic resistance genes in the milk of antibiotic-treated groups. The data support the use of non-antibiotic alternatives for drying off in cows.
Paper 2: Influence of age, socioeconomic status, and location on the infant gut resistome across populations
Early life is a crucial stage as the foundation of microbiota development takes place which affects the infant health and immunity in later life. With increasing indications of ARGs in infants, we investigated the gut resistome profile during early life at a wider geographic level. Many highly ARG-abundant species including Escherichia, Klebsiella, Citrobacter species that we observed are well-known pathobionts found in the infant gut in early life. High abundance of these species and a diverse range of ARGs in their genomes point toward the infant gut, acting as an ARG reservoir. We also observed that ARG abundance decrease with age which could be attributed to the developing microbiome.
Paper 3: Early life exposure of infants to benzylpenicllin and gentamicin is associated with a persistent amplification of the gut resistome
Infant gut microbiota is highly unstable, and several factors affect it including early life antibiotic exposure which can have potentially long lasting effect. But the long-term longitudinal impact of antibiotic exposure in early life, together with mode of delivery on infant gut microbiota and resistome, has not been extensively studied. This study describes the longitudinal impact of early life antibiotic use on the microbiota and antibiotic resistance profile in 45 infants from week 1 to year 2 of life.
This is of importance as antibiotic resistance is a global threat and antibiotic resistance genes (ARGs) can be transferred through horizontal transfer, and antibiotic resistant strains can lead to formation of multi-drug resistant strains. Further, limited treatment in very early life to two antibiotics can lead to an amplification of the resistome later as it selects for bacteria that presumably carry multidrug resistance from their history which can complicate treatments in later life.