SUPERBUGS

Microbes + Antimicrobial Resistance = Superbugs


What are microbes?


To know about Superbugs, let's understand microbes and drug-resistant pathogens. Microbes are microscopic, unicellular organisms. They are all around us, they live in soil, water and air. The most common types are bacteria, virus and fungi. Well-known examples of bacteria include Salmonella and Staphylococcus. Most bacteria aren't harmful to humans. Many of them live on or in our body and help us to stay healthy.


Bacteria don’t usually come to mind as a leading threat to global health. Yet, infections caused by drug-resistant bacteria are forecasted to result in more deaths than cancer and diabetes combined. Less than 1% of microbes are responsible for infectious diseases. Medications are the most common therapeutic method used to treat infections. The more we use them, the more we kill susceptible microbes, leaving microbes that are resistant to drugs. Resistance to drugs is a consequence of microbial evolution via natural selection.


The action is due to environmental pressure, which undergoes mutation allowing them to survive and to reproduce (The evolutionary concept of “Survival of the fittest”). This trait will pass on to their offspring, which will be a fully resistant generation. These resistant microbes grow and multiply in clinical settings and in the environment known as drug-resistant pathogens or antimicrobial resistance (AMR). This makes drugs used for treatment ineffective and people are more vulnerable to infections.¹ ²


Image: NIAID-RML/Handout via REUTERS.







How are harmful bacteria stronger than drugs?


Antimicrobial-resistant organisms are found in people, animals, food, plants and the environment (in water, soil and air). They can spread from person to person or between people and animals, including from food of animal origin. The main drivers of antimicrobial resistance include the misuse and overuse of antimicrobials; lack of access to clean water, sanitation and hygiene (WASH) for both humans and animals; poor infection and disease prevention in health-care facilities and farms; poor access to quality, affordable medicines, vaccines and diagnostics; lack of awareness and knowledge.

The emergence and spread of drug-resistant pathogens that have acquired new resistance mechanisms, leading to antimicrobial resistance, continue to threaten our ability to treat common infections. Especially alarming is the rapid global spread of multi- and pan-resistant bacteria also known as “Superbugs” that cause infections that are not treatable with existing antimicrobial medicines such as antibiotics. AMR is one of the top 10 global public health threats facing humanity. The cost of AMR to the economy is significant. In addition to death and disability, prolonged illness results in longer hospital stay. Without effective antimicrobials, the success of modern medicine in treating infections, including during major surgery and cancer chemotherapy, would be at increased risk.


Annual deaths due to AMR are anticipated to rise to 10 million worldwide by 2050. This public health problem is growing attention globally. Several countries are facing the emergence of bacteria that are completely resistant to available antibiotics.

India carries one of the largest burdens of drug-resistant pathogens worldwide, including the highest burden of multidrug-resistant tuberculosis, alarmingly high resistance among gram-negative and gram-positive bacteria even to newer antimicrobials such as carbapenems and faropenem since its introduction in 2010. Regional studies report high AMR among pathogens such as Salmonella typhi, Shigella, Pseudomonas, and Acinetobacter.


Annually, more than 50,000 newborns are estimated to die from sepsis due to pathogens resistant to first-line antibiotics. While exact population burden estimates are not available, neonates and elderly are worst affected. Two million deaths are projected to occur in India due to AMR by the year 2050. The high burden of AMR in India is driven by multiple factors - antibiotic over-prescription, poor understanding of its dangers and contribution to AMR on the part of the provider as well as patients who lack knowledge regarding appropriate antibiotic use.³


The superbugs in hospitals are created due to misuse and overuse of antibiotics were 190 million doses of antibiotics are administered each day out of which 50% of these prescriptions are unnecessary and over $1.1 billion spent annually on unnecessary antibiotic prescriptions for respiratory infections in adults. Over 70% of kids get better within two or three days from common infections, and giving antibiotics when they aren't necessary can lead to the development of superbugs over time. The ongoing COVID 19 pandemic may further contribute to the growing global problem of AMR. In the recent study 72% hospitalized COVID 19 patients were prescribed antibiotics while only 7% demonstrated superimposed bacterial or fungal co-infections. WHO reports widespread usage of azithromycin with hydroxychloroquine although it is not yet recommended outside of COVID-19 clinical trials.


Examples of Superbugs are:


Carbapenem-resistant Enterobacteriaceae (CRE) - Evades the strongest antibiotics, making infections almost untreatable, has a fatality rate of up to 50%. The CDC reports that in the last 10 years, the percentage of Enterobacteriaceae that have become resistant to antibiotics has increased from 1% to 4%.

Methicillin-resistant Staphylococcus aureus (MRSA) - A drug-resistant phenotype that has been circulating for over 45 years, almost as long as methicillin has been on the market. The incidence of MRSA varies from 25 per cent in western part of India to 50 per cent in South India.. Community acquired MRSA (CA-MRSA) has been increasingly reported from India.

Clostridium difficile - Resistant to multiple antibiotics contributes to approximately 15,000 deaths per year, C. difficile bacteria causes potentially fatal diarrhea, usually in elderly, or immune-compromised individuals. Studies in India have shown a prevalence rate of 7.1% to 26.6% in hospitalized patients.³

Candida auris - Resistant to most antifungal drugs, Candida auris is a strain of yeast associated with high rates of death among patients where the fungal infection is able to enter the bloodstream. In India a study was conducted on critically ill coronavirus disease patients admitted in an intensive care unit during April - July 2020. Candida auris accounted for two thirds of cases; with case-fatality rate of 60%. Hospital-acquired C. auris infections in coronavirus disease patients may lead to adverse outcomes and additional strain on healthcare resources.

How to prevent AMR?

Hygiene is key

  • 50% of men and 25% of women don't wash their hands after using the restroom

  • 2 and 10 million bacteria is present in between fingertip and elbow

  • Damp hands spread 1,000 times more germs than dry hands

  • The number of germs on fingertips doubles after using washroom or touching any common touch points

  • Germs can stay alive on hand for up to three hours

  • Hand washing either by soap water wash or ABHR at least 8 times a day is very essential. COVID 19 pandemic has taught us all the importance of hand washing

Eat for Wellness

  • Yoghurt contains probiotics, one probiotic supplement a day reduces sick days by 33%

  • Oats and barley contain beta-glucan, a fibre with antimicrobial and antioxidant effects - these help antibiotics work better

  • Watermelon and Broccoli contain glutathione, which stimulates immune system

  • Sweet Potato contains Beta-Carotene (which convert to Vit A) and builds healthy skin (first defense against bacteria and viruses)

  • Green tea can help antibiotics be three times more effective in fighting drug-resistant bacteria

Take drugs as directed

  • Don't stop treatment a few days early because you're feeling better

  • Taking the full course of antibiotics is the only way to kill harmful bacteria

  • A shortened course of antibiotics, on the other hand, often wipes out only the most vulnerable bacteria while allowing relatively resistant bacteria to survive

  • Never take antibiotics without a prescription

  • Make sure immunization are up to date

If urgent action is not taken we shall approach a ‘Post-antibiotic era’ — a time where antibiotics are pretty much useless and drug-resistant superbugs can easily decimate our health and lives will be lost for minor infections or injuries.


In the second part we shall focus on evolving technologies around diagnostics and prevention in the fight against AMR.

References


¹F. C. Tenover and J. E. McGowan, “Antimicrobial Resistance,” International Encyclopedia of Public Health, 2008, doi:10.1016/B978-012373960-5.00452-4.

²“Superbugs_ How We’re Making Harmful Bacteria Stronger With Antibiotics,” n.d.

³Avika Dixit et al., “Antimicrobial Resistance: Progress in the Decade since Emergence of New Delhi Metallo-β-Lactamase in India,” Indian Journal of Community Medicine, 2019, doi:10.4103/ijcm.IJCM_217_18.

⁴CDC, “Biggest Threats and Data | Antibiotic/Antimicrobial Resistance | CDC,” 2019, 2019, https://www.cdc.gov/drugresistance/biggest-threats.

Getahun, Haileyesus, et al. “Tackling antimicrobial resistance in the COVID-19 pandemic.”Bulletin of the World Health Organization 2020

Joshi, Sangeeta, et al. “Methicillin resistant Staphylococcus aureus (MRSA) in India: Prevalence & susceptibility pattern.” Indian Network for Surveillance of Antimicrobial Resistance (INSAR) group, India.

Chowdhary, Anuradha, et al. “Multidrug-Resistant Candida auris Infections in Critically Ill Coronavirus Disease Patients, India, April-July 2020.” 2020.