Question

5 Points Chapter-3: Case Study / Home Work-2 1. PARROT FEVER Thinking that their two sons should have a pet, Joe and Charlotte buy the boys a pair of cockatiels. The birds initially seem healthy but within a few weeks they appear inactive and listless. Concerned about the birds, Joe takes them to the veterinarian, who diagnoses a case of psittacosis, otherwise known as parrot fever. The veterinarian recommends giving the birds food that has been impregnated with the antibiotic tetracycline. He also tells Joe to exercise great care while cleaning the cage for the next few weeks. Curious about the disease, Joe reads up on psittacosis. He finds that it is caused by the bacterium Chlamydia psittaci, which is most common in parrots and related birds. Pet stores that sell birds are a regular source of C.psittaci infection. Joe also learns that these bacteria are unusual in that during an infection, they are not easily destroyed by phagocytic immune system cells How do the bacteria resist destruction by phagocytic cells? (Part& Composition) 2. ANTHRAX In late 2001, soon after the terrorist attacks of September 11th, the United States was in the grip of a new terror threat. Between October 4th and November 20th, twenty-two cases of anthrax were reported. Eleven of these cases were cutaneous anthrax, while eleven were pulmonary anthrax. Five of the patients who contracted pulmonary anthrax died. The source of the outbreak was traced to letters contaminated with Bacillus anthracis endospores. The letters were deliberately sent by the perpetrator to a variety of prominent individuals, including members of the media and the US. Senate. Twenty of the 22 patients (91%) were mail handlers or others who entered workplaces where contaminated mail was processed or received. Why is Bacillus anthracis such a potent bioterrorism agent? 3. Consider two new antibiotics. Antibiotic A disrupts cell membranes. Antibiotic B interferes with the synthesis of peptidoglycan. Which of these drugs do you think is safer to use to treat an infection in an animal and why?

Answer 1

Bacterial avoidance of phagocytosis:
1. They produce factors that prevent the fusion of lysosome with phagosome.
2. Some bacteria also can survive withing phagosome due to their thick cell wall.
3. They can prevent the recognition and uptake by phagocytic receptors.
4. They can also avoid contact with phagocytes by remaining in an inaccessible region.
5. Some bacteria inhibit phagocytic chemotaxis.

Bacillus anthracis has been considered as a potential biological warfare agent.
1. It can form hard spores which can be dispersed by aerosols.
2. It rarely causes secondary infections.
3. It has high fatality rate if untreated.
4. It starts as the normal flu and leads to mortality.

Antibiotic B is a potential drug to use against an infection. this is because it interferes with a pathway that is absent in animals cells. So, there will not be any cross-reactivity.