Molecular Basis of Infectious Diseases — DU B. Sc. (Hons) Biochemistry Previous Year Question Papers

There are 6 questions: 1. (a) Give reasoning for the following : (i) Bats are reservoirs of various viral diseases (ii) ID50 dose for some bacteria is low and for some it is very high (iti) New emerging diseases are majorly zoonotic (io) Candidiasis is common in AIDS patients (u) Rabies can be prevented by vaccination. (b) Define the following terms : (ii) Dimorphie fungi (iii) Pathogenicity island (io) Nosocomial infection 2. Answer the following questions: (i) There are various immunological tests for tuberculosis. Describe any two. (it): Describe the various virulent factors of Salmonella typhi. (iti) Which antigenic proteins are first detected during HIV infection? What is their significance in diagnosis ? * . (io) How are parasitic diseases historically diagnosed.? Describe Montenegro test. (v) What are Koch's postulates ? 3. (a) Describe the drugs used in the DOTS therapy. What is MDR-TB and (b) What is HAART? How can AIDS be cured completely? (c) Draw the structure of influenza virus. What are the functions of hemagglutinin and neuraminidase? 15 4. Differentiate between the following : (a) Antigenic shift and antigenic drift • (b) Bactericidal and bacteriostatic antibiotics (c) Hepatitis A and hepatitis B (d) Oral and injectable polio vaccine (e) Passive and active immunization (a) How was the BCG vaccine developed? Why is it ineffective in adulthood? (b) Most of the drugs are for the pathways or mechanisms exclusive to the pathogen. Explain by describing an antifungal, antibacterial, antiviral and antiparasitic drug. (e) What is bioterrorism? : 5,8,2 6. (a) How is malaria transmitted ? Describe various develomental stages of malarial parasite. Why is there periodic fever in malarial infection? (b) What are the three types of leishmaniasis? How are amastigotes different, from promastigotes ? (e) What are the various biosafety levels? Discuss with examples. 15