Antimicrobial Resistance Threatens Wild Big Cats: IVRI Study

Nilesh Vijaykumar | Hyderabad

Antimicrobial Resistance is no longer restricted to hospitals or polluted urban water bodies. Multiple Drug Resistant bacteria have been detected in the blood of Wild Lions, Tigers, and Leopards. AMR is also an ecological threat.

A study by the Indian Veterinary Research Institute (IVRI) located at Izatnagar, Uttar Pradesh has reported finding Multiple Drug Resistant (MDR) bacteria in wild Lions, Tigers, and Leopards. 

The scientists tested blood samples collected from the hearts of 40 carcasses of big cats — Lions (9), Tigers (26), and Leopards (5). Among them, 30 big cats were from zoos, and the remaining 10 were from the wild. 

And these are not your average MDR bacteria. Some are ESBL-producing and Carbapenem-resistant as well. 

Don’t be deterred if you’re hearing these terms for the first time.

Read ahead. There’s more clarity on what they are and why this is really fucked up. 

What’re Drug-Resistant Bacteria? 

Ever heard or read about the menace called Antibiotic Resistance among bacteria? 

It’s all in the name. 

Bacteria that have developed resistance to a particular antibiotic are known as antibiotic-resistant. They are also popularly known as Drug-Resistant bacteria and in a broad sense, as Antimicrobial Resistant (AMR) bacteria. 

There’s a nastier version of the antibiotic-resistant bacteria — the Multiple Drug Resistant (MDR) bacteria. It is resistant to more than one antibiotic.

Then there are the Extensively Drug Resistant (XDR) bacteria that are resistant to most antibiotics and can be killed by only 1-2 antibiotics. 

An estimated 1.27 Million people died in 2019 due to infections caused by Antimicrobial Resistant bacteria according to the Global Burden of bacterial antimicrobial resistance in 2019: a systematic analysis published in The Lancet. 

How Do Bacteria Develop Resistance To Drugs/Antibiotics? 

Bacteria naturally develop resistance to antibiotics over a period of time. But this process has been accelerated due to the misuse of antibiotics like:

• Sale of antibiotics over the counter/without any prescription
• Unwarranted prescription of newly developed and powerful antibiotics by doctors, for even minor infections without trying older, effective antibiotics.

Read this for more info. 

What Did The IVRI Scientists Study?

The IVRI scientists studied blood samples collected from the hearts of Lions, Tigers, and Leopards that died in the zoo (30 big cats) and in the wild (10 big cats).

These blood samples were collected by zoo and wildlife veterinarians for post-mortem and sent to the Clinical Epidemiology Laboratory at IVRI for bacteriological analysis. 

Why was blood collected from the heart studied? 

Deaths due to bacterial causes are often associated with sepsis. This can be confirmed through the detection of bacteria in the blood collected from any vital internal organs. However, detection of bacteria in the blood collected from the heart is the best confirmation of a systemic infection leading to death. 

Shocking Findings — Drug-Resistant Bacteria In Wild Lions, Tigers, and Leopards

It’s shocking to note that not just Drug Resistant but Multiple Drug Resistant bacteria were detected in all the ten blood samples collected from the wild Lions(2), Tigers(6), and Leopards(2). 

Something More Concerning 

Among the ten blood samples collected from the wild Lions, Tigers and Leopards, Five blood samples were detected with ESBL-producing bacteria and Three with Carbapenem-resistant bacteria. 

What are ESBL-producing bacteria? 

ESBL is an acronym for the enzyme Extended Spectrum Beta-Lactamase. Some bacteria produce the ESBL enzyme, which makes them immune to a large variety of drugs/antibiotics. So, basically, these are bacteria that can actively defend themselves against our attack by antibiotics. 

What are Carbapenem-resistant bacteria? 

You’ve to first know that antibiotic is a term that lumps various drugs that help in the treatment of bacterial infections. There are various ‘classes’ of antibiotics like Penicillins, Fluoroquinolones, Cephalosporins, etc. 

Carbapenem is among the latest class of antibiotics. They are known as “last-resort” antibiotics, used for treating infections caused by Multiple Drug Resistant bacteria. 

Drug Resistance Among Zoo Animals 

Among the 30 blood samples collected from the zoo, big cats — Lions(7), Tigers(20), and Leopards(3) — 20 samples had MDR bacteria, 13 samples had Carbapenem-resistant bacteria and 10 had ESBL-producing bacteria. 

Overall — Among the 40 blood samples, 25 percent samples contained MDR bacteria, 37.5% samples contained ESBL-producing bacteria, and 40% samples contained Carbapenem-resistant bacteria. 

IVRI Scientists Have Called Their Findings Alarming — Why? 

Drug resistance is a transmittable characteristic. Yes. It’s a superpower against antibiotics that bacteria can share. A bacteria that have developed resistance to a drug or multiple drugs, can transmit its resistance genetically to other bacteria in the environment. But we’re in such deep shit that this is not the alarming part. This is just a fact now. 

Here are the alarming findings: 

Alarming finding 1 — Carbapenem-resistant bacteria in big cats. 

The IVRI researchers point out, Carbapenems are usually not recommended or are rarely administered to animals. Then how the hell are the Carbapenem-resistant bacteria ending up in the big cats – 40% of all big cat blood samples had them? 

Alarming finding 2 —  The finding of ESBL-producing bacteria among the big cats. 

The IVRI researchers report that E.coli is the most common cause of death due to bacterial infection among big cats. And guess what? E.coli belongs to the family of bacteria called Enterobacterales, which are experts in producing ESBL enzymes to defend themselves against antibiotics. 

Alarming finding 3  — Multiple drug-resistant bacteria among big cats in the forests. 

Where are they contracting them from? Is it due to consuming cattle reared by humans that are often administered antibiotics? Are veterinarians administering Carbapenems to farm animals, that often come under attack by big cats in villages located on the edges of forests? Is this an unexpected medical fallout of the man-animal conflict? 

Studies on these topics are rare. Hope someone digs deeper. 

Ends/