General · 31st January 2016
Antimicrobial Resistance: Cause For Concern
I was recently at an infectious disease conference where this topic was the hot item on the agenda. It has also been a priority item for the World Health Organization (WHO), who recently proclaimed the week of November 16th World Antibiotic Awareness Week. I would like to share some information and thoughts with regards to antimicrobial use and misuse. This is a global problem that needs attention from those who manufacture them, prescribe them, and use them. Antimicrobials need to be Handled with Care.
Microbes, which include bacteria, fungi, parasites and viruses, are agents that cause infectious disease. Antimicrobials are those products (like antibiotics, antivirals) developed that when taken by an individual, kill the offending microbes. Antibiotic resistance is therefore a subset of antimicrobial resistance as antibiotics are effective only in killing bacteria. Antimicrobial resistance occurs when, for a variety of reasons, not all of the offending microbes are killed. These remaining microbes can mutate in response to the antimicrobial used so that giving further doses will not harm it. Thus it becomes immune to that particular drug. Microbes become very effective in mutating, then passing this mutation off to their offspring to ensure survival. The development of antimicrobial resistance is a natural phenomenon. However, certain human actions have accelerated its emergence. The most important cause is misuse and overuse. Inappropriate use occurs when the wrong drug, strength, or duration is prescribed. Poor drug manufacturing also plays a role. Finally, routine use of anti-microbial for food-producing animals and poultry flocks also contributes to the problem.
Infections caused by resistant microorganisms often fail to respond to standard treatment, thus resulting in prolonged illness and potential increased mortality. For example, individuals with methicillin-resistant staphylococcus aureus (MRSA) infection are estimated to be 64% more likely to die than individuals with the non-resistant form of the infection. If individuals are infected for longer timeframes, they also remain infectious for longer, thus increasing the risk of spreading resistant microorganisms to others. Resistant microbes can also colonize on others without causing infection. These individuals are then carriers, who can pass the microbes to others (most frequently those who have poor immune systems), causing infection. Health care costs are increased not only because of the use of multiple drug therapies, but also because of longer hospitalization and convalescence. In all countries, use of second and third line drugs are expensive, adding to cost to the health system. In poorer countries, these drugs are not always available and without their use, resistance infections multiply. Without effective antimicrobials for prevention and treatment of infections, all modern medicine gains (cancer chemotherapy, organ transplants) can be compromised.
According to a global survey conducted by WHO, antimicrobial resistance is present in all parts of the world. In North America, most individuals are aware of MRSA . Staphlococcus aureus represents one of the most common bacteria that inhabit the human skin that can cause infection. MRSA is now resistant to first line antibiotics. Similarly another common bacteria, enterococcus, found in the human gut, urinary tract and the environment, have a resistant strain called vancomycin resistant enterococcus (VRE). This means it is resistant to the antibiotic vancomycin, one of the primary antibiotics used to treat this infection. Urinary tract infections (UTI’s) caused by Escherichia coli (E coli) are now increasingly resistant to ciprofloxacin, one of a group of fluorquinalones that are used to treat other infections. Gonorrhea, a sexually transmitted genital infection now has many resistant strains and in some countries there is a strain now resistant to the antibiotic of last resort. Globally, 3.5% of new cases of tuberculosis (TB) along with 20.5% of previously treated cases are now estimated to be resistant to the standard antibiotics. Malaria is another disease where there are now resistant sub-types. With HIV, the continued expansion of the use of HART therapy (standard anti-retroviral therapy for those with HIV which continues for life) is now causing the emergence of drug resistance. Even with antiviral drugs prescribed for influenza (which have only been developed over the last 10 years), there is now resistance to all influenza A viruses.
When 12 countries were questioned by WHO with regards to antibiotic resistance, 64% of respondents believed it was an issue but few understood why or what they could do to address it. 64% believed that antibiotics could be used to cure cold and flu, which are viruses. When further questioned, 75% thought that antibiotic resistance occurred when the body became resistant to antibiotics, 66% believed that they were not at risk if they took their antibiotics as prescribed, 50% thought it was a problem only for those who take antibiotics regularly, and more than 50% felt there was nothing they could do to stop resistance from occurring.
Clearly much needs to be done to educate all to become wiser stewards with regards to antimicrobial use. At present, only one quarter of the worlds’ countries have a national plan to combat antimicrobial resistance. Policies need to be put into place to increase surveillance of antimicrobial infections, as well as to implement infection prevention and control. Drug manufacturers need increased monitoring for quality control of antimicrobials. Health authorities need to monitor the use of antimicrobials as well as provide leadership and education for clinicians to make appropriate choices when these drugs as used. Hospitals and clinics themselves need to educate staff and visitors on infection control practices. Hand washing remains a priority for EVERYONE. All health practitioners need to practice smart use of antimicrobials, prescribing only when needed, using the best drug for the right infection with the right dose for right duration.
The agricultural sector also needs to do their part by reducing their use of antimicrobials. This can be done through vaccination, use of antimicrobials only when infection occurs and applying good practices and hygiene in all stages of animal growth and slaughter or plant production.
On an individual level, vaccination is a good way to prevent antimicrobial use as it prevents infection in the first place. This becomes even more important with global travel and immigration. Please use antibiotics only when prescribed by a certified health practitioner. Do not order antibiotics from the internet, or take them on spec. from third world pharmacies. Always take the full prescription, even if feeling better. Please do not share antibiotics or use left over antibiotics for something else. Take all unused antibiotics back to the pharmacy for proper disposal. Throwing them in the garbage, or flushing them risks them getting into the water table. Getting prescriptions for antibiotics “in case” for travelling is not a good idea as you could be taking the wrong antibiotic for the wrong illness. Prevent infections by staying home when ill. Avoid contact with those who are ill. Above all, please wash your hands with soap and water when appropriate.