ANTIBIOTIC RESISTANCE

Antibiotic Resistance

I am sure that everyone knows what is antibiotic and many people sure had use it either on their own or given by a doctor when we are sick and today our topic will be on “Antibiotic Resistance”. So, first of all  

What is Antibiotic resistance ?

Antibiotic resistance occurs when an antibiotic has lost its ability to effectively control or kill bacterial growth; in other words, the bacteria are "resistant" and continue to multiply in the presence of therapeutic levels of an antibiotic.

I believe the next thing that will flow in all­­­_­­­­­ your mind will be WHY do bacteria become resistant to antibiotics?

Let me explain about it in simple and easier way. Firstly, Antibiotic resistance is a natural phenomenon. When an antibiotic is used, bacteria that can resist that antibiotic have a greater chance of survival than those that are "susceptible"(harmed by antibiotics). Susceptible bacteria are killed or inhibited by an antibiotic, resulting in a selective pressure for the survival of resistant strains of bacteria.

Besides that some resistance occurs without human action, as bacteria can produce and use antibiotics against other bacteria, leading to a low-level of natural selection for resistance to antibiotics. However, the current higher levels of antibiotic-resistant bacteria are attributed to the overuse and abuse of antibiotics. In some countries and over the Internet, antibiotics can be purchased without a doctor's prescription. Patients sometimes take antibiotics unnecessarily, to treat viral illnesses like the common cold!

To understand the causes  of antibiotics resistance lets watch this short clip about antibiotic resistance....

How To Bacteria Become Resistant?

• BY GENETIC MUTATION 
• BY ACQUIRING RESISTANCE FROM ANOTHER BACTERIUM

1. The first way is by mutations, rare spontaneous changes of the bacteria's genetic material, are thought to occur in about one in one million to one in ten million cells. Different genetic mutations yield different types of resistance. Some mutations enable the bacteria to produce potent chemicals (enzymes) that inactivate antibiotics, while other mutations eliminate the cell target that the antibiotic attacks. Still, others close up the entry ports that allow antibiotics into the cell, and others manufacture pumping mechanisms that export the antibiotic back outside so it never reaches its target.

2.Besides mutation, bacteria can acquire antibiotic resistance genes from other bacteria in several ways. By undergoing a simple mating process called "conjugation," bacteria can transfer genetic material, including genes encoding resistance to antibiotics (found on plasmids and transposons) from one bacterium to another. Viruses are another mechanism for passing resistance traits between bacteria. The resistance traits from one bacterium are packaged into the head portion of the virus. The virus then injects the resistance traits into any new bacteria it attacks. Bacteria also have the ability to acquire naked, "free” DNA from their environment.

In conclusion, any bacteria that acquire resistance genes, whether by spontaneous mutation or genetic exchange with other bacteria, have the ability to resist one or more antibiotics. Because bacteria can collect multiple resistance traits over time, they can become resistant to many different families of antibiotics.

Examples of bacteria that resistant to antibiotics     

1. Staphylococcus aureus (‘golden staph’ or MRSA)

     2. Neisseria gonorrhoeae (the cause of gonorrhoea)

     3.Methicillin-resistant Staphylococcus aureus (MRSA)

 4.     vancomycin-resistant Enterococcus (VRE)

     5. Multi-drug-resistantMycobacterium tuberculosis (MDR-TB)

     6.Klebsiella pneumonia carbapenemase-producing bacteria (KPC).

How does antibiotic resistance spread?

1. Through transmission of antibiotic resistant bacteria in the community

2.Through transmission of antibiotic resistant bacteria in hospitals

 Can bacteria lose their antibiotic resistance?

Yes, antibiotic resistance traits can be lost, but this reverse process occurs more slowly. If the selective pressure that is applied by the presence of an antibiotic is removed, the bacterial population can potentially revert to a population of bacteria that responds to antibiotics.

Ways to prevent antibiotic resistance

The most important ways to prevent antibiotic resistance are

    ·  Minimise unnecessary prescribing and overprescribing of antibiotics. This occurs when people expect doctors to prescribe antibiotics for a viral illness (antibiotics do not work against viruses) or when antibiotics are prescribed for conditions that do not require them.

   · Complete the entire course of any prescribed antibiotic so that it can be fully effective and not breed resistance.

   · Practise good hygiene and use appropriate infection control procedures.