Bordetella pertussis is an aerobic, Gram-negative, coccobacillus bacterium. It is non-spore forming and non-motile, usually containing a capsule. Its preferred temperature to grow is in the range of 35-37C. Under the microscope, it is identified by its rod like cell shape, as well as its short, oval size. During a blood agar culture test for this particular bacteria, the specimen tends to take 3 to 6 days to form a pinpoint sized colony. B. pertussis appears to only affect the human species, therefore identifying humans as its only host and reservoir. It has multiple virulence factors that allow it to be an aggressive pathogen.
B. pertussis has several virulence factors, mainly involving proteins that have been separated into 2 main classifications: adhesions and toxins. The adhesions category consists of the following: filamentous hemagglutinin (FHA), fimbriae (FIM), and pertactin (PRN). FHA is a very large surface protein, and it works to help B. pertussis attach to the host cell. FIM are surface appendages, a common finding in other bacteria. However, these appendages contain a factor called agglutinogens, which is used to serotype this bacteria.1 PRN has shown to take on a defense role, fighting any neutrophils that may come to the rescue. As stated above, the other classification of B. pertussis virulence factors is toxins, and it composed of adenylate cyclase toxin (ACT), pertussis toxin (PT), and tracheal cytotoxin (TC). ACT is actually quite an important virulence factor for this bacteria. It functions by injecting itself into the host cell, where it increases cAMP rates. This causes phagocyte function to cease, and may trigger apoptosis in selected cells.1 The exact role of PT is not yet fully understood, but it has come...
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...es of Pertussis each year4; this number has drastically decreased since vaccinations against this illness were implemented into the health care system.
As science has proven to show, B. pertussis is a stealthy and relentless bacterium. Using only the human species as its reservoir and host choice, its various virulence factors allow it to be successful in regards to infecting individuals. The devastating illness it causes, Pertussis or Whooping Cough, remains to be a global issue today. Although this bacterium provides resistance to regular antibiotics, a special antibiotic family known as macrolides may be used as a treatment option. However, the best practice for protection against this specimen is by obtaining the recommended vaccinations. As society moves forward, the field of science continues to look for new options to make B. pertussis an issue of the past.
S. pyogenes is a bacterium that permeates our society. Today it is commonly known as the cause of “Strep. throat,” or Streptococcal pharyngitis. Modern medicine has caused the eradication of most of its advanced infections, while this most common form of infection still thrives. It is very contagious, and pyogenes travels quickly through places where bacteria flourish, such as schools and health institutions. The body cannot fight this bacterium very well without help, and S. pyogenes was a common cause of death until the introduction of antibiotics in the twentieth century. It has a number of ways to subdue the immune system, but it is almost completely vulnerable to penicillin, even after decades of exposure. While generally no more than a nuisance, this bacterium continues to be an interesting topic of discussion. (6,3,2)
Because B. pertussis is a gram-negative bacteria, it possesses the endotoxin lipopolysaccharide (LPS). However, its LPS is different from that of the other gram-negative bacteria, in that it is heterogeneous with an alternative form of the Lipid A, called Lipid X. Although not fully understood at the time, it seems that Lipid X has a greater capacity for virulence.
Whooping cough is a highly contagious and acute respiratory disease caused by an aerobic Gram negative encapsulated coco-bacillus bacterium, Bordetella pertussis. It is a strict human pathogen with no known animal or environmental reservoirs and an air-borne disease. On inhalation, Bordetella pertussis colonizes the ciliated cells of the bronchio-epithelium to cause disease characterised by; epithelial damage, hyper mucus secretion, pulmonary edema and paroxysmal coughing. It is often accompanied by pneumonia, otitis edema, seizures, post-tussive vomiting and encephalopathy (1).
Evans, A. S. (1991). Bacterial Infections of Humans (Vol. 1, 2nd ed.). New York: Plenum Medical Book Company.
Trabelsi, H., Dendana, F., Sellami, A., Sellami, H., Cheikhrouhou, F., Neji, S., … Ayadi, A. (2012). Pathogenic
Clostridium perfringens is a gram-positive spore-forming bacillus involved in foodborne illness and wound infection. It is an obligate anaerobe and the only member of the genus Clostridium that is non-motile. This microorganism is normally present in soil and decaying vegetation and is an inhabitant of animal and human intestines. According to the Centers for Disease Control and Prevention, C. perfringens is one of the most common sources of foodborne illness in the United States, being the cause of an estimated 1 million cases each year. However, it is also prevalent worldwide. This bacterium has the shortest reported generation time of any organism at 6.3 minutes in thioglycollate medium, making it particularly virulent after initial inoculation.
perfringens is the most common cause of foodborne illness in the United States, with a million cases each year (CDC, 2014). C. perfringens is able to produce up to 15 different toxins, making it versatile. These toxins are used to isolate the five different types of C. perfringes: type A, B, C, D, and E. The four toxins that are primarily used to isolate the different types include alpha, beta, epsilon, and iota-toxins. Type A is the most common and most variable, and subdivided into entertoxigenic and non-enterotoxigenic strains (Herholz et al., 1999). Enterotoxigenic type A and C are associated with equine enterocolitis, gas gangrene, infections, avian and canine necrotic enteritis, colitis in horses, and diarrhea in pigs (Divers and Ball, 1996). Types B, C, D, and E can cause severe enteritis, dysentery, toxemia, and high mortality rates in young lambs, calves, pigs, and foals. Types B, C, D, and E have been intermittently associated with foal enterocolitis, and equine antibiotic associated diarrhea (Divers and Ball, 1996). Even though the alpha toxin is noted to be relatively nonpathogenic, the beta2 toxin plays a significant role in digestive disease, specifically, enterocolitis in equine (Herholz et al., 1999). This is mainly due to the C. perfringens entertoxin (CPE), the main virulence factor that initiates many critical gastrointestinal diseases across species (Herholz et al. 1999). CPE works in a four-step mechanism against membrane action (CDC, 2014). First,
Vaccines have been used to prevent diseases for centuries, and have saved countless lives of children and adults. The smallpox vaccine was invented as early as 1796, and since then the use of vaccines has continued to protect us from countless life threatening diseases such as polio, measles, and pertussis. The Center for Disease Control and Prevention (2010) assures that vaccines are extensively tested by scientist to make sure they are effective and safe, and must receive the approval of the Food and Drug Administration before being used. “Perhaps the greatest success story in public health is the reduction of infectious diseases due to the use of vaccines” (CDC, 2010). Routine immunization has eliminated smallpox from the globe and led to the near removal of wild polio virus. Vaccines have reduced some preventable infectious diseases to an all-time low, and now few people experience the devastating effects of measles, pertussis, and other illnesses.
Poll, T., Opal, M.S. Pathogenesis, treatment, and prevention of pneumococcal pneumonia. 2009. Lancet 374: p. 1543–56. Retrieved from http://www.umcutrecht.nl/NR/rdonlyres/A34BBBAE-1C56-42C1-B308-070A781CE82C/20643/2Review_pneumocpneumonia_poll_opal_lancet.pdf
T. pallidum is highly sensitive to oxygen and has a decreased ability to survive when not in human body temperature environments 1. The mode of transmission is through sexual contact or vertical transmission from the mother to the fetus. T. pallidum lacks the lipopolysaccharide which is the endotoxin normally present in gram negative bacteria1. The bacterium does produce many lipoproteins which are thought to prompt the inflammatory mediators through the recognition of toll-like receptors1. T. pallidum has a virulence factor of being highly motile due to its ability to propel itself forward by rotating on a longitudinal axis1. The spirochetes easily penetrate the skin or mucosal membranes and spread throughout the lymph nodes and then the blood circulation, affecting many parts in the body1.
Pathogens are a type of microorganism that spreads viral and bacterial diseases. These diseases when present in human blood and body fluids are known as blood borne pathogens, and can spread from one person to another. (Worcester polytechnic institute) The most serious types of blood borne diseases are the hepatitis B virus (HBV) and hepatitis C virus (HCV), which can cause liver damage; and HIV (human immunodeficiency virus), which is responsible for causing AIDS (acquired immune deficiency syndrome). The blood borne pathogens can be spread when the blood or body fluids (semen, vaginal fluid, breast milk, and amniotic fluid) of an infected individual comes into contact with mucous membranes or an open sore or cut on the skin of another person. Mucus membranes are located in the eyes, nose, mouth, and other areas as well. ("Bloodborne pathogens: MedlinePlus Medical Encyclopedia") Two of the most common ways that pathogens are transmitted is through the exchange of fluids during sexual intercourse or by sharing infected IV needles. (Worcester polytechnic institute)
Streptococcus pneumoniae is a Gram-positive and fast-growing bacteria which inhabit upper respiratory tract in humans. Moreover, it is an aerotolerant anaerobe and usually causes respiratory diseases including pneumonia, otitis media, meningitis, peritonitis, paranasal sinusitis, septic arthritis, and osteomyelitis (Todar, 2003). According to Tettelin et al., more than 3 million of children die from meningitis or pneumonia worldwide (2001). S.pneumoniae has an enzyme known as autolysin that is responsible for disintegration and disruption of epithelial cells. Furthermore, S.pneumoniae has many essential virulence factors like capsule which is made up of polysaccharides that avoids complement C3b opsonization of cells by phagocytes. Many vaccines contain different capsular antigens which were isolated from various strains (Todar, 2003). There are plenty of S.pneumoniae strains that developed resistance to most popular antibiotics like macrolides, fluoroquinolones, and penicillin since 1990 (Tettelin et al., 2001). Antibiotic resistance was developed by the gene mutation and selection processes that, as a consequence, lead to the formation of penicillin-binding proteins, etc. (Todar, 2003).
These days whooping cough, also known as Pertussis, is not a serious disease because there are vaccinations available to prevent its occurrence. However, when I was five years old a vaccination was available but neither my siblings nor myself had been vaccinated against it and due to its highly contagious nature, I contracted whooping cough from my older sisters.
The bacterium Bordetella Pertussis causes Pertussis also known as the whooping-cough. This is an extremely contagious respiratory tract infection which causes the lining of the air way to become inflamed and damaged. This leads to an excess production of mucous which irritates the respiratory tract and causes the cough element of the disease. Pertussis can cause other serious illnesses and is usually spread through coughing or sneezing while in close contact with other people who then breathe in the bacteria causing disease. You can get Pertussis more than once sometimes even years apart at any age. If you have not completed the primary vaccination series you are at higher risk for severe illness. “Since the 1980’s, the number of reported Pertussis cases has gradually increased in the United States. In 2005, over 25,000 cases of Pertussis cases were reported in the United States, the highest number of reported cases since 1959. Approximately 60 percent of the cases were in adolescents and adults, a result of decreasing immunity in this population” (Department of Health, n.d.).
Pertussis, the ‘P’ in DTaP, can potentially be fatal to infants. It is caused by Bordetella pertussis bacterium. Pertussis is spread from droplets in the air. When you breathe in the droplets, the bacteria starts to incubate. You may begin to have a cough, runny nose, and some sneezing. As time goes on, the cough gets worse and worse. Hence