27.1

Introduction

When we look back on the history of human diseases, infectious diseases have

accounted for a very large proportion of diseases. It was, however, only in the latter

half of the nineteenth century when microorganisms were discovered to be respon-

sible for a number of infectious diseases that have been plaguing mankind since

ancient times. Thereafter, the first antimicrobial agent salvarsan was formulated by

Ehrlich in 1910 for the cure of syphilis. In 1935, a new class of synthetic drugs called

sulphonamides was developed by Domagk and other researchers to cure bacterial

infections successfully (Yousef et al. 2018). However, these compounds had

limitations in terms of safety and efficacy. In 1928, Sir Alexander Fleming discov-

ered penicillin, an excellent and outstanding antimicrobial agent in terms of safety

and efficacy that lead to the golden period of antimicrobial therapy. It came into

clinical use in the 1940s.

For the next two decades, new types of antimicrobial drugs were developed one

after the other, leading to remarkable advances in the treatment of infectious diseases

and fate of mankind (Saga and Yamaguchi 2009). This gave rise to an overwhelmingly

optimistic view that infectious diseases will be eliminated in the near future, provided

new antibiotics continue to be developed. However, the development of new types of

antibiotics has slowed in the mid-1980s, and very few have been developed in the last

quarter of a century (Shallcross et al. 2015; Silver 2011). At present, fewer new

antimicrobial agents are being introduced in the market. In addition, infections with

drug-resistant organisms remain an important problem in clinical practice that is

difficult to solve. As a consequence of this, isolates are now appearing which are

resistant to almost every antibiotic available, raising the spectre of untreatable infection

even at the world’s most advanced medical centres (Snitkin et al. 2012).

In fact, by the early 1940s, resistance to antimicrobials drugs has been observed

and reported in various studies (Abd-El-Aziz et al. 2017). For instance, in 1941,

Abraham

and

co-workers

(1941)

observed

that

cultures

of

Staphylococci

sp. developed resistance by continuous subculture in the presence of penicillin,

and in 1942, Rammelkamp and Maxon (1942) isolated four strains of penicillin-

resistant Staphylococci sp. during treatment of local infections with penicillin.

Within two decades of penicillin’s introduction, most strains of S. aureus isolated

in large hospitals were resistant to penicillin and to other antibiotics including

streptomycin, tetracycline, and erythromycin.

Widespread scientific consensus has concluded that the human overuse and

mismanagement of antimicrobial agents have contributed to the rapid development

of antimicrobial resistance (AMR) in microorganisms. AMR arises when the

microorganisms which cause infection (e.g. bacteria) survive exposure to a medicine

that would normally kill them or stop their growth. This allows those strains that are

capable of surviving exposure to a particular drug to grow and spread, due to the lack

of competition from other strains. Antibiotics are the preferable treatment for the

cure of chronic bacterial infection. These antibiotics have a potent outcome and also

it is cost-effective, but with time the overuse and misuse of antibiotics create resistant

towards broad spectrum of bacteria. This has led to the emergence of ‘superbugs,’

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