MICROBE 2018 recap - Microbes that Know No Borders - AMR, Humans and Animals

Dr. Susan Sanchez is from the College of Veterinary Medicine at the University of Georgia. She is the section head for Microbiology and Molecular Biology, the Assistant Director of the Biomedical Health Science Institute and the Chair of One Health.

Her research interests include: (i) Antimicrobial resistance (AMR) spread in humans and animals (ii) Staphylococcus and Salmonella with a focus on MRSA and (iii) Diagnostic testing for zoonses present in animals.

Her talk focused on how AMR spreads between humans and animals. Interestingly she started off by saying her adviser had said a long time ago that clinical microbiology is dead, we have antimicrobials. I think we can all agree, that is not true. Estimates suggest that a failure to address AMR could lead to 10 million deaths by 2050.



Today we gain a 'new' way of looking at our dogs...

• Working in a vet teaching hospital they were noticing a lot of nosocomial animal infections and in particular resistant E. coli infections.
• One dog "Brutus" got a resistant infection and died from septic shock. The E. coli isolated from him was resistant everything except amikacin and imipenem.
• They found that this bacterium was transferred to the dog (a labrador) in the cage next to Brutus who developed a resistant UTI.
• In examining the hospital environment they were finding this resistant E. coli everywhere - same resistance pattern.
• What they found was that rodents were transmitting this E. coli  across the teaching hospital!

https://www.cartoonstock.com/directory/h/hiv.asp

"We love our pets...we kiss them more than we should"

So how big of a problem are these infections in our dogs...our pets? No one really knows it's not something that's routinely tracked by the CDC or USDA, though steps are being taken to start addressing this such as the FDA Vet-LRN (Vet-LIRN now) Program which focuses on Staphylococcus, Salmonella and E. coli. 

• 2018 Solicitation for Vet-LIRN
• FDA Website on Vet-LIRN

Other efforts include:

• The USDA APHIS program collecting isolates through the National Animal Health Laboratory network (NAHLN)
• Global Salmonella Resistome Data collected by the USDA

So what drives these bacteria to jump hosts and cross species barriers? All of these factor contribute to a bacteria adapting to survive however it can including jumping hosts and exchanging AMR genes.

• Half of the Earth-bacteria are killed by bacteriophages every day
• Bacteria have to contend with each other in predator/prey type interactions via type VI secretion systems. 
• Bacteria contend with human interventions such as antimicrobial compounds
• The environment itself is constantly changing - pH, heavy metals, residual antibiotics, other toxic environmental compounds.
• Bacteria are constantly transferring and picking up genetic elements including resistance genes from the environment. These elements or pieces of DNA are constantly being released into the environment via contact mediated bacterial 'warfare'...nothing less than a microbial Game of Thrones - sex, war and transfer of the powers that be!

BTW: LivingInAMicrobialWorld - has a blog post that discusses AMR in the context of Game of Thrones if you are interested with such highlights as:

• White Walkers = Near unkillable superbugs
• The Starks = Scientists and Media saying "Doom, Gloom, Apocalypse!"
• The Nights Watch = Doctors, scientists, farmers, politicians...anyone trying to do something about it.
• Lannisters/King's Landing = Most governments/the powers in charge
• The Wall = Time...the wall will eventually fall...the bugs are going to spread
• Dragonglass = New antibiotics
• Peasants = Everyone else.

Other resources illustrating this Game of Thrones behavior within microbes:

• Science Daily Article - Understanding bacterial wargames inside our bodies
• Podcast from In Situ Science - "Microbial Game of Thrones with Gal Winter"

And it's not just dogs we have to worry about:

• Geckos destined for the pet trade carry antibiotic resistant cultures. 
• By 2050 we'll have 9.8 billion people and we have to feed them, this will increase the production of food animals. 
• The US has the largest broiler chicken industry in the world with Georgia being the largest producer within the US.
• Antibiotics are used for metaphylaxis, prophylaxis and to promote feed efficiency and weight gain the animals - just take a look at chickens from the 1950s and now?!

https://academic.oup.com/ps/article/93/12/2970/2730506

The cross species issues just keep popping up...

• Chickens have their own issues with Avian Pathogenic E. coli (APEC)
• Colistin resistance has been detected in pigs was originally thought to be confined to China then was found subsequently to actually be distributed in human guts in China, Europe and the USA suggesting a potential food chain dissemination pathway.
• In some countries Colistin is fed to chickens! (not in U.S.)
• AEM article on use of colistin on pig and chicken farms in Southern Vietnam
• mcr1 was identified and an APEC isolate
• Carbarpenem resistance has also been detected in APEC, the paper in Nature Microbiology found that there was prevalence of NDM-1 and mcr1 in Chinese poultry production. This paper also introduced the idea of the Phantom Resistome... dogs, chickens, farmers, birds, flies... the environment harbors reservoirs of AMR genes and presents a picture of how resistance may be moving between all these hosts. The article is paywalled but you can see some of the figures on Semantic Scholar.

So what can we do? Well...we can limit those 'kisses' and the amount of saliva swap we do with our pets and of course just good practices in hygiene while research continues to combat AMR threats.

https://www.cartoonstock.com/directory/d/dog_attacks.asp