CHAPTER 1 INTRODUCTION
Human health is under serious threat globally by microorganisms, especially viral and bacterial diseases. Bacteria and viruses can be found on surfaces and could potentially cause harm. Infectious diseases are emerging at an alarming rate and have contributed to a good number of deaths globally. Although over the past decade the mortality rates of these diseases have declined, the impact these diseases have on the world remains substantial. Infectious diseases are the second leading cause of death worldwide, with 57 million deaths occurring each year, as reported by the Center for Disease Control and Prevention (CDC) (Fauci, Touchette, & Folkers, 2005).
There are increasing global concerns about certain issues such as antibiotic-resistant bacteria, Zika virus, HIV/AIDS, Ebola virus, and SARS. These diseases have a high mortality rate and have been identified by the World Health Organization as diseases likely to cause epidemics (WHO, 2015). In Africa, emerging diseases are a public health concern not only due to their high mortality rate, but also due to the fact that developing countries lack good health facilities. Despite countermeasures that have been developed due to advanced technology (therapeutics and vaccines), infectious diseases that affect both human health and the economic stability of societies have not been contained (Morens & Fauci, 2013). Bacteria and viruses that have developed resistance to antimicrobial agents are more life threatening and are now a serious public health concern.
Antimicrobial resistance has become a major global concern. Aside from bacteria and viruses, other microorganisms are rapidly developing a resistance to antimicrobial agents being used to kill them. This evolution makes the treatment of infectious diseases less effective and, in the long run, may cause death. Though sometimes viewed as an apocalyptic fantasy, antibiotic resistance, which might allow even minor injuries to kill, is indeed a reality in the 21st Century (WHO, 2014). Antimicrobial resistance is a global concern because it will make the treatment of infectious diseases less effective and prolong illnesses (WHO, 2016). Additionally, organ transplantation, C-section delivery, and other medical procedures may become more risky due to the lack of effective antimicrobials.
The increasing global concern for antimicrobial resistance has urged scientists to further research this issue. Projections made by scientists showed deaths that could be attributable to antimicrobial resistance yearly by 2050 will be high (Fig.1). Most deaths will most likely occur in Asia and Africa. Although antimicrobial resistance is increasing, less researches have been carried out on new drugs to curtail these resistant pathogens.
Various bacteria have developed a resistance to particular antibiotics. To name a few, bacteria such as Mycobacterium tuberculosis and Staphylococcus aureus have developed a resistance to certain antibiotics (Shanks & Peteroy-Kelly, 2009). Klebsiella pneumoiae, a bacterium known for causing intestinal infections, is resistant to carbapenem antibiotics and has spread globally, leading to several deaths (WHO, 2016). Additionally, Escherichia coli which causes intestinal infections, is resistant to fluoroquinolone antibiotics. Currently, many countries around the world have no effective treatment for these bacteria. Other bacteria, such as S. aureus (Fig.2) and members of the family Enterobacteriaceae, which are resistant to methicillin and carbapenem, have also contributed to many untreatable conditions in different countries (WHO, 2016). The more resistant a strain of bacteria is, the greater the threat to human health.
Increasing health risks due to microorganisms
Pathogens can be found on almost all surfaces. Bacteria have the ability to grow anywhere, even in narrow surfaces, and have the ability to move (Männik et al., 2009). They can also survive on surfaces for an extended period. Some diseases caused by bacteria and viruses are life threatening and require immediate attention (Morris, 2016). Prophylaxis such as vaccinations may help lower the probability of getting infected. Also, good hygiene behaviors and good cleaning practices could lower the risk of getting infected. Globally, pandemics are rapidly spreading and have left people concerned about their health. People are more likely to catch diseases caused by bacteria and viruses in places where people congregate and where they make frequent contact with non-living objects.
