Superbugs; The Next Big Challenge For Mankind

Written By: LAKINDU SOORIYAARACHCHI, Class Of 2025

This blog is about the development of antibiotic resistance and emergence of Superbugs as one of the major threat to human kind.

INTRODUCTION

"SUPERBUGS" what comes to your mind when you first read or hear this word? Well, whatever comes to your mind, I bet you won't give much thought about it afterwards as you happily go about your life. But unfortunately, you wouldn’t be able to brush aside the thought that easily in the near future... WHY? I'll tell you about it in a bit. But first, what actually are superbugs?

They can be simply understood as strains of bacteria, viruses, parasites and fungi that are resistant to most of the antibiotics and other medications commonly used to treat the infections they cause. The general term used for this scenario is antimicrobial resistance (AMR). They are mostly found in hospitals and other healthcare facilities where they frequently are in contact with antibiotics and other antimicrobial drugs. I'll be focusing my attention on bacteria as they are the most common and abundant type of superbugs which affect us. But keep in mind all the other types of microbes can emerge as resistant superbugs. We are living in a world roaming with bacteria.

They are so ubiquitous that you will find them in every corner of this planet, from the deepest and darkest depths of the ocean to the top of the tallest mountains. Bacteria have evolved to survive in harshest environments you can imagine. They are found in polar ice caps, and places where neither oxygen nor sunlight reaches. I think you won’t be surprised when I say they are also growing in radioactive waste, toxic chemicals & boiling hot springs. But of all the places bacteria are found, they seem to have a special affinity to the human body. There are more than 10,000 different species of bacteria living on or in the human body at any given time. In fact, there are more bacterial cells living in humans than that of our own cells 

ANTIBIOTICS AND EMERGENCE OF RESISTANCE TO THEM.

Even though there are trillions of bacteria living inside us, not all of them are harmful. In fact, some of them are of great use to us. Well, the problem for us is that the ‘not so nice’ bacteria cause a lot of nuisances in our lives when they cause infections. Diseases caused by bacteria and other microbes was the leading cause of death for centuries until the miraculous discovery of Penicillin by Alexander Fleming in 1928.

The discovery of the first antibiotic (penicillin) and subsequent antibiotics in the following decades in the 20th century led the way for antibiotics to emerge as the mainstay treatment modality against bacterial infections. So, the doctors had a free ‘get out of jail’ card at their disposal and started prescribing antibiotics without thinking twice about any potential long-term consequences. Now nearly 100 years down the road, with over prescription and improper adherence to treatment regimens we have created perfect monsters that we don’t yet have the complete knowledge of.

WHAT ANTIBIOTICS ARE SUPERBUGS RESISTANT TO?

Superbugs are resistant to many commonly used antibiotics including penicillin, methicillin, cephalosporins and fluoroquinolones etc. It is now evident that superbugs have developed resistance to more potent and last resort antibiotics (the big guns) like vancomycin, imipenem, meropenem, tigecycline and colistin.

WHY BACTERIA BECOME RESISTANT TO ANTIBIOTICS?

Of the many reasons for the increase in the antibiotic resistance (ABR) and MDR which led to the emergence of many resistant pathogens (including ESKAPE pathogens discussed later) is due to improper and rash overuse of antibiotics for treatment of infections caused by bacteria or even non-bacterial aetiologies. This is becoming common not only in healthcare, but also in the animal, and agricultural sector.

Another common cause of antibiotic resistance is due to incorrect dosing and inadequate adherence to proper treatment guidelines. When a low therapeutic dose of antibiotics is prescribed, or a patient takes doses less than what they are prescribed, bacteria get the chance to adapt to the treatment regime. At lower doses, or when a course of antibiotics is not completed, certain strains of the bacteria have the ability to develop drug-resistant strains through different natural biological processes.

HOW DOES BACTERIA DEVELOP RESISTANCE?

As mentioned earlier this can be attributed to different biological processes. Random genetic mutations occurring in bacteria are a common mechanism in developing resistant strains. Natural selection supports the strains of bacteria that have developed a certain mutation that allows them to survive. Some strains are capable of inter-strain horizontal gene transfer, allowing them to pass resistance genes from one pathogen to another.

There are few ways this can occur,

a) Transformation - Genetic change of a cell due to the direct intake and incorporation of genetic material from its exterior surroundings through the cell membrane.

b) Transduction - Foreign genetic materials are introduced into a cell by a virus or viral vector. E.g. Via Bacteriophages

c) Conjugation - Transfer of genetic material between bacterial cells by direct cell-to-cell contact. This is achieved through a pilus

ESKAPE

This is an acronym given to six of the most virulent and resistant bacterial pathogens. They include; Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa Enterobacter spp. These Gram-positive and Gram- negative bacterial pathogens have developed ways to hide, evade and escape commonly used antibiotics that are thrown at them due to increasing multidrug resistance (MDR). This makes ESKAPE pathogens the leading culprits of life-threatening hospital-acquired infections; especially in critically ill and immunocompromised patients.

WHO GPP LIST

This is an acronym given to six of the most virulent and resistant bacterial pathogens. They include;

• Enterococcus faecium,

• Staphylococcus aureus,

• Klebsiella pneumoniae,

• Acinetobacter baumannii,

• Pseudomonas aeruginosa

• Enterobacter spp.

These Gram-positive and Gram- negative bacterial pathogens have developed ways to hide, evade and escape commonly used antibiotics that are thrown at them due to increasing multidrug resistance (MDR). This makes ESKAPE pathogens the leading culprits of life-threatening hospital-acquired infections; especially in critically ill and immunocompromised patients. The GPP list classifies pathogens into 3 categories; critical, high and medium. The graveness of ESKAPE pathogens is obvious when all six species are ranked in either critical (A. baumannii, P. aeruginosa, K. Pneumonia and Enterobacteriaceae) or high (E. faecium, S. aureus) categories.

WHERE ARE WE NOW?.... AND WHERE ARE WE HEADED?

I mentioned that we wouldn’t be able to neglect the thoughts on Superbugs in the near future, right? I’ll tell you why that is using some data. According to the new UN Environment report it is estimated that nearly 5 million global deaths were attributed to AMR annually. This surpasses the death due to major killers HIV/AIDS and malaria. But the most worrying news is that this number could go up to 10 million by the year 2050.

To put into perspective that’s the same as the number of deaths due to cancer today. It is not only the loss of lives that will be on the line, but if left unchecked the economic burden that the world will eventually have to face is going to be unfathomable. According to the world bank estimation, the loss of Gross domestic product (GDP) will be in the range of US$ 3.4 trillion annually and push more than 24 million people into extreme poverty.

So, the bottom line is that superbugs are emerging as a major threat to all of humanity… maybe sooner than any of us might want. It is therefore a responsibility of all of us to become aware of all the potential harm it will bring upon us and to fight together to keep them at bay.