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Competition between Human and Bacterium

——The Story of Antibiotic

Few centuries ago, There were 1/3 population of Europe died of outbreak of the plague. Smallpox killed half of the population in Mexico. Humans are an extremely aggressive species. There are countless wars between humans. However, according to historical and medical expert estimate that the people who died because of micro-organisms, parasites and infections were much more than people who died in wars. But World War II was a notable exception. The things changed the situation was the first antibiotic in human history- Penicillin. It was said that World War II brought to mankind things which have revolutionary impact are include the atomic bomb , penicillin and computers and so on, In fact, many medical history experts believe that penicillin was into the pharmacopoeia showing the birth of modern medicine, even before this, we already have a rabies vaccine. After extensive application of antibiotics, medicine for the first time really had the ability to save humanity from the largest battlefield.

1928 is a very important year in history of mankind against bacteria landmark. The famous British bacteriologist, Alexander Fleming discovered the penicillin by accident. 16 years later, his discovery made a big difference in World War II. Now, I will tell you the story of penicillin.

       It was Alexander Fleming at St Mary’s Hospital Medical School who noticed a mould growing on a culture plate of bacteria one day in September 1928. Around the Penicillium notatum mould was a clear area where the colonies of bacteria appeared to have been dissolved. Fleming set about establishing the identity of the substance that was killing the bacteria, giving it the name ‘penicillin’. But Fleming only continued to study penicillin for a year or so, and he never got to the stage of  purifying and testing its effects against bacterial infections when injected into a living animal or patient.

Professor Howard Florey became Professor of Pathology at Oxford in 1935, moving into a splendid new department, the Sir William Dunn School of Pathology. Florey quickly recruited Ernst Chain to work with him, and they began to look at a range of substances that might have an effect on bacteria.

Around the time Britain declared war on Germany, Chain and Florey came to the conclusion that penicillin was far more effective in combating bacteria than the other candidates. But there was no simple means of testing the activity of the samples of penicillin they produced. And they needed a good method to extract the penicillin from cultures of the Penicillium mould.

By 25 May 1940, the team had reached a point where they could carry out a new experiment that would test whether penicillin could be an important antibacterial drug. Eight mice were given lethal doses of streptococci. Four of the mice were then given injections of penicillin. By the next morning all the untreated mice were dead while those that had received penicillin survived for days to weeks.

With this result, Florey realized that he needed to expand production – an effective treatment for infection could be a valuable contribution to Britain’s war effort. By February 1941 Florey felt he had enough penicillin to begin trials in humans.

The Dunn School became a factory to produce enough penicillin for trials in humans. With the help of Charles Fletcher, a young doctor at the Radcliffe Infirmary, on 12 February 1941, Albert Alexander, a 43-year-old policeman, became the first patient to be treated with penicillin. He had scratched his face on a rose bush, the wound had become infected and the infection had spread. Fletcher injected him with penicillin regularly over four days, and within 24 hours he was greatly improved. But supplies of the new drug ran out before his cure was complete. He relapsed at the beginning of March, and died two weeks later.

Fleming, Florey and Chain were jointly awarded the Nobel Prize for physiology or medicine in 1945, recognizing the tremendous contribution of penicillin to human welfare.

In 1943, Ukraine microbial scientists Wasserman discovered streptomycin. It was the end of tuberculosis bacilli streak. 1950s to the 1970s was the golden age of antibiotics developed. The kinds of new antibiotics increased year by year. Chlortetracycline (1947), chloramphenicol (1948), oxytetracycline (1950), Nystatin (1950), erythromycin (1952), Kanamycin (1958), etc. are found in this period. Human had an overwhelming advantage in war with bacterium. However, when people are immersed in the joy of victory, the upcoming new disaster struck.

Cunning resistant bacteria occurred potency variability - large amount of antibiotics can kill the bacteria in one fell swoop. But small amount of stimulus or regular under the circumstances can induce resistance genes in antibiotic play a role in the inhibition. Once the bacteria produce antibodies, It will be passed on to their offspring to fight against their enemies. It also enhance their competitiveness in its class.

From 1950s to 1960s, people discovered the drug-resistant bacteria. In 1968 , scientists were in the development of vancomycin. They had declared "superbugs" will be repulsed.

Now, however, MRSA (acronym of methicillin-resistant Staphylococcus aureus Bacteria) which is crazy "superbugs" have defeated their opponents - vancomycin.

 In 2000, listing of Pfizer's linezolid, has caused a sensation in the medical profession. Because it is the world's first synthetic Oxazolidinone antibiotics, People give it high hopes .

But only less than 1 year, the reports of emergence of linezolid -resistant enterococci forced people to have to find new antibiotics to replace its treatment.  Confident mankind should say goodbye to the era of far ahead of the bacteria. Antibiotics and bacteria are into the see-saw war and humans are always in dangerous.

In the "Red Queen", a book has a saying, "You need keep running to remain in place". After penicillin was used in large-scale investment in clinical applications, the arms race between humans and microbes has been going on for decades. How long can we maintain the advantage? I do not think people are willing to go back to the dark ages when average lifetime was of 40 years old or less. To maintain the advantage, we need to developing new antibiotics. In addition, we also need to strengthen supervision of antibiotics, medical systems industries rational use of antibiotics.