General Background
Salmonellosis, a food borne bacterial infection is caused by genera of bacteria called Salmonella. This food borne infection is a major public health concern and a significant amount of government spending is spent as an effort to help contain it. A substantive percentage of population succumbs to the effects of Salmonellosis. Some government institutions have so far been very successful in containing human Salmonellosis whereas others are still grappling with its effects on human population. Presently, there are at least 2500 known serotypes of Salmonella. In the last decade of the 20th Century, there emerged strains of Salmonella, which exhibited signs of resistance to a range of antibiotics.
This has up to date remained a public health concern. The resistance has been attributed to use of the antibiotics in humans and animals where it is principally used in human husbandry. Human Salmonellosis has developed resistance to a variety of antimicrobials (Falkow and Kennedy, 2001). This is a real health scare because antibiotics that were considered as first choice agents can no longer be relied on. Human Salmonellosis is primarily contracted after consumption of contaminated food from animal origin. However, green vegetables that have been contaminated by manure can also aid in its transmission. Serotypes that have specific host spectrum can be very invasive and life threatening when they cause disease in humans. However, most serotypes boast a broad host spectrum. These cause gastroenteritis, a condition that can be very critical to those with weakened immunity. Human Salmonellosis can also cause blood stream infection.
Control Strategies
Human Salmonellosis can be treated by using a group of antimicrobials known as fluoroquinolones. However, they are only used for optimal treatment purposes. These antimicrobials are fairly inexpensive, are effective and are easily absorbed. Cephalosporin that is administered through injection is used with children having severe human Salmonellosis as opposed to quinolones. As substitutes, ampicillin and chloramphenicol can be used sometimes.
Resistance to Drugs
Over the years, Salmonella has developed resistance to antimicrobials and this has been caused by mutations in the bacteria’s DNA. This resistance is transferred to other bacterial strains by transfer of bacterial DNA. Multidrug resistance is normally transferred through bacterial plasmid. Resistance was not witnessed when fluoroquinolones were first administered to humans. However, upon administration to animals, resistant was encountered. This subsequently spread to humans (WHO, 1998).
Evolution of serotypes
Evolution of Salmonella serotypes has been seen for the past 30 years. The most recent epidemic has been caused by Salmonella enteritidis. This caused health scare in many European countries (Ewald, 1994). It has since slightly declined. However, Salmonella typhimurium has re-emerged as the principal serotype of human Salmonellosis.
The consequences of resistance in terms of human health
Antimicrobial agents that are used to treat human Salmonellosis affect the intestines and expose them to hosts of infections. Antimicrobial agents used in treating upper respiratory tract infections expose users to risk of Salmonella infection. To control drug resistant Salmonella, it is advisable that the use of antimicrobial agents is reduced. This curbs further contamination by drug resistant Salmonella.
Steps that can be taken slow down evolution of antibiotic resistance
It is advisable that people only use antibiotics when they have to. Antibiotics should not be used in infections that are not bacterial. The course of treatment has to be completed. In essence, all antimicrobials given by the physician must be used as directed. Livestock should not be fed with antibiotics if the war on antibiotic resistance is to be won.
Reference List
Ewald, P.W. (1994). Evolution of Infectious Disease. Oxford: Oxford University Press.
Falkow, S. and Kennedy, D. (2001). Antibiotics, Animals, and People—Again! Science, 291: 397.
WHO (World Health Organization). (1998). Use of Quinolones in Food animals and Potential Impact on Human Health. Geneva, Switzerland: W.H.O.