Antibiotics are drugs that destroy microorganisms or inhibit their growth so are used to treat bacterial infections in many areas of healthcare. There are several different variations and types with 6 main classifications: penicillins,
cephalosporins, aminoglycosides, tetracyclines, macrolides and fluoroquinolones.  Each type destroys bacteria in a different way, many, including penicillin, punch holes into the cell membrane of the bacteria so it is damaged and eventually dies. Others such as Erythromicin and Ciprofloxacin prevent the bacteria carrying out Protein synthesis or DNA replication therefore growth is slowed down and eventually stops.
How does resistance occur?
While antibiotics have and continue to be used very successfully in treating illness and infection, their effectiveness is steadily decreasing as more and more bacteria can survive, this is known as antibiotic resistance. While many human factors have contributed to the issue, it ultimately occurs due to genetic mutations. Within each targeted population of bacteria there will be a small number which possess a genetic mutation that prevents them from being damaged or killed by the drug such as developing an impermeable cell membrane. Therefore these select few bacteria are able to survive the attack of the antibiotics, allowing them to reproduce which produces a large number of resistant bacteria, which increases quickly due to bacteria’s rapid division and reproduction. The resistant genes and mutations can also be passed on to other bacteria they come into contact with, further increasing the resistant population. This means that eventually a whole species of bacteria can become resistant to specific antibiotics, rendering them ineffective against certain diseases.  However many human causes also extend the problem, notably the unnecessary prescription of antibiotics by doctors for viral infections or suspected bacterial illnesses as this allows resistant strains to easily develop and remain in the person. Many patients also fail to complete their full course of antibiotics if they feel better, so some bacteria survive, allowing them to develop and pass on further resistance.
One of the most prominent and threatening antibiotic resistant strains is methicillin-resistant Staphylococcus aureus , known as MRSA. Staphylococcus bacteria are present on the skin of a large number of people within the general population and don’t cause them any harm, yet if it enters the blood through an opening in the skin it can lead to potentially fatal serious infections including sepsis. While many of the problems it causes could be treated relatively easily with antibiotics, this is becoming more difficult as various strains of the bacteria have developed resistance against the majority of antibiotics. Some resistant pathogens have also caused problems on a global scale such as Multi-drug resistant tuberculosis (MDR-TB), contracted by over 480,000 people a year worldwide.  This disease is more difficult to control as it is common in poorer countries who can’t afford sufficient diagnosis and treatment, increasing the spread. To be successfully treated and cleared TB requires a drug treatment plan of at least 6 months, if this isn’t completed bacteria can easily survive in the body and develop resistance. Therefore upon reinfection or the bacteria being spread to others, which is common in the crowded living conditions of the poor countries in which it occurs, they are resistant to more antibiotics and it is more difficult and expensive to treat. TB is only classed as multi drug resistant when it cannot be treated by the strongest drugs; isoniazid and rifampin, currently around 5% of global TB cases, yet this number is continually increasing as more strains becomes resistant. Resistance has grown to such an extent that there is also extensively drug resistant TB (resistant to fluoroquinolones and injectable drugs) suggesting that the issue will only worsen.
Antibiotic resistance causes a complex mix of both physical, social and economic effects on all aspects of healthcare. The most obvious is that as more and more pathogens become resistant to various antibiotics, less are effective and fewer treatment options become available to both doctors and patients, leading to more lengthy treatment and a higher mortality rate. There is a greater risk surrounding procedures, commonly surgery and chemotherapy, that may involve antibiotics to prevent or treat resultant infections,, so patients are more likely to have secondary complications, some of which can be fatal.
The consequences of resistance also puts the NHS under immense financial strain with all consequences having to be funded. As common drugs become more ineffective stronger ones will have to be utilised incurring higher costs, or administered more directly through injections or IV lines, also procedures that increase costs. Increased hospital stays because of prolonged treatment drains funding while patients with resistant infections, such as MRSA, have to be isolated in hospital, reducing space and facilities. There are also social issues that can occur, due to increased isolation of patients and difficulties between doctors and the public as fewer antibiotics requested can be prescribed.
It is hoped that new antibiotics can be discovered and developed in the future, and although a new antibiotic hasn’t been discovered since the 1980’s, there have been many promising suggestions. One is that humans may contain forms of antibiotics themselves, as it has been noticed that some people don’t have forms of bacteria in their body that others do, suggesting it may have been killed by a natural form of antibiotic. One German study has focused on Staphylococcus bacteria strains found in the nose, as it has been noted that many people with the lugdunensis strain don’t have S.aureus, suggesting it has a form of defence. Animal testing with the resultant drug Lugdunin has resulted in infections being reduced and even cleared.  Although it faces a long road to being effective and approved for human use, it is just one of many promising studies suggesting one of the answers could be the human body itself.
While antibiotic resistance can never be eradicated as a problem, there are many policies and strategies that can be undertaken by healthcare workers and the public to reduce its impact and increasing further. The main aim is to reduce the number of unnecessary antimicrobial prescriptions, largely by reducing prescriptions for minor and otherwise treatable illnesses such as mild throat infections. Decreasing the use of ‘broad spectrum’ antibiotics such as meropenem (that are effective against both ‘Gram-positive’ and ‘gram-negative’) could be effective because these are generally used when the cause of infection is not immediately clear in an emergency situation, such as suspected Meningitis or Septicaemia so various strains are able to develop resistance.
Some responsibility lies with patients as it is essential they follow the correct guidelines when taking antibiotics by fully completing the course, so no bacteria can survive and develop resistance. It is also necessary that they do not share antibiotics with others who have not had them prescribed as they may have a different infection that doesn’t respond to the drugs, giving another strain the opportunity to become resistant.  This awareness is largely raised through social campaigns and information such as European antibiotic awareness day and information provided in GP surgeries and hospitals to warn patients of the importance of increasing resistance. Yet perhaps the most effective method is to prevent many antibiotics even being required by improving infection control and prevention across all healthcare settings. This can be as simple as promoting hand washing in hospitals to reduce the transmission of infection and improving provisions for isolating patients with easily transferable infections such as MRSA and Clostridium Difficile.
Therefore it is clear that antibiotic resistance is a complex global problem that is potentially the biggest current threat to health care, however if everyone takes responsibility and has the aim of preventing the issues from developing further, it is possible to prolong the spread of resistance, till we find an alternative solution.
About the Author
Alexandra Nelson, UK
Alexandra is a member of the Young Scientists Journal’s Bolton Hub.