Question

A missionary couple, living in West Africa bought their 4-year old son to the Emergency room as he had fever and a pinkish rash has been developing on his hands and feet at first then it spread to both arms and legs. There are no other symptoms that the child feeling very fatigued. 1. This disease is most likely caused by what bacteria? Name the disease. 2. How would epidemiology assist you in finding the sources of this illness? 3. The boy had all of his vaccines so why does he have such a disease? 4. What course of treatment would you order and why? What type of antibiotic would you use and why? 5. What are the virulence factors for the causative agent? Explain the mode of action of these factors

Answer 1

1. ANS: It is a Scarlet fever and the Scarlet fever is also known as scarlatina. It is a bacterial infection that caused by Streptococcus pyogene, which are found on the skin and in the throat. The same bacteria that causes scarlet fever causes strep throat. It's called "group A strep."

2. ANS: Rashes are one of symptom of scarlet fever. The red color of rash is due to damage of small blood capillaries and blood vessels.

3. ANS: Because there is no vaccine to prevent the Scarlet fever. Oral penicillin is the standard treatment for this.

4. ANS: Scarlet fever can be treated easily with antibiotics. Liquid antibiotics, such as penicillin or amoxicillin, are often used to treat children.

5. ANS: Virulence factors include M protein, Protein F and lipoteichoic acid for adherence;

Hyaluronic acid capsule that inhibits phagocytosis; M-protein to inhibit phagocytosis

Invasins such as streptokinase, streptodornase