Q70. Which vaccine entered an Indian Phase-III clinical trial announced by ICMR and Panacea Biotec in August 2024?
[RRB Technician Grade-I, 20 December 2024]
(A) Dengue vaccine
(B) Typhoid conjugate vaccine
(C) Malaria vaccine
(D) Hepatitis E vaccine
Answer: (A) Dengue vaccine
Explanation: The announcement concerned a tetravalent dengue vaccine trial. Dengue has four major viral serotypes, making balanced immune protection particularly important. Clinical trials assess vaccine safety and effectiveness; starting Phase III does not itself imply a vaccine is licensed for general use.
Q69. For what public-health purpose is the Wolbachia method applied?
[UPSC CSE Prelims 2023]
(A) Reducing mosquito transmission of viral illnesses
(B) Converting straw to packaging
(C) Manufacturing bioplastics
(D) Making biochar
Answer: (A) Reducing mosquito transmission of viral illnesses
Explanation: Wolbachia is a bacterium introduced or maintained in mosquito populations to reduce their ability to transmit dengue and some other arboviruses. The method addresses the vector rather than treating infected patients and is investigated as a sustainable disease-control approach.
Q68. Which pathogen–disease assignment is correct for peptic ulcer, dengue, elephantiasis and malaria?
[UPPSC PCS Prelims 2023]
(A) Bacteria, protozoan, worm, virus
(B) Virus, bacteria, worm, protozoan
(C) Bacteria, virus, worm, protozoan
(D) Worm, virus, bacteria, protozoan
Answer: (C) Bacteria, virus, worm, protozoan
Explanation: Peptic ulcers are often associated with Helicobacter pylori bacteria; dengue is viral; elephantiasis commonly results from filarial nematodes; and malaria comes from Plasmodium protozoa. The question tests pathogen groups rather than simply the names of diseases.
Q67. Which pair of hepatitis viruses is principally associated with transmission through infected blood?
[WBCS Mains (Science) 2023]
(A) Hepatitis A and E
(B) Hepatitis A and B
(C) Hepatitis B and C
(D) Hepatitis D and E only
Answer: (C) Hepatitis B and C
Explanation: Hepatitis B and C can spread through contaminated blood, including unsafe injections or shared needles. Hepatitis B can also spread sexually and during childbirth. Hepatitis A and E predominantly follow faecal–oral pathways, frequently linked to contaminated food or water.
Q66. Which illness among these is caused by a virus?
[SSC CHSL 2022 cycle, 21 March 2023]
(A) Chickenpox
(B) Tuberculosis
(C) Whooping cough
(D) Malaria
Answer: (A) Chickenpox
Explanation: Chickenpox is caused by varicella-zoster virus and commonly gives an itchy vesicular rash. Tuberculosis and whooping cough are bacterial infections, while malaria is protozoan. Correctly identifying the pathogen helps distinguish vaccine approaches and appropriate antimicrobial treatment.
Q65. Which mosquito genus transmits the virus responsible for chikungunya?
[SSC CHSL 2022 cycle, 10 March 2023]
(A) Culex
(B) Mansonia
(C) Aedes
(D) Anopheles
Answer: (C) Aedes
Explanation: Chikungunya virus is an alphavirus spread mainly by Aedes aegypti and Aedes albopictus mosquitoes. It often causes fever accompanied by pronounced joint pain. Aedes mosquitoes can also carry dengue and Zika viruses, whereas Anopheles is best known for malaria transmission.
Q64. Which statements about COVID-19 vaccines are correct:
Covishield is mRNA;
Sputnik V uses a viral vector;
Covaxin uses inactivated virus?
[UPSC CSE Prelims 2022]
(A) First and second
(B) Second and third
(C) First and third
(D) All three
Answer: (B) Second and third
Explanation: Covishield uses a non-replicating adenoviral vector, not an mRNA platform. Sputnik V also uses adenoviral vectors, whereas Covaxin is an inactivated whole-virus vaccine. Different platforms expose the immune system to viral antigens without causing ordinary COVID-19 disease.
Q63. What kind of pathogen produces dengue fever?
[RRB NTPC CBT-2, 14 June 2022]
(A) Virus
(B) Fungus
(C) Bacterium
(D) Nematode
Answer: (A) Virus
Explanation: Dengue results from infection with dengue virus, typically transmitted by infected female Aedes mosquitoes. Four major dengue serotypes are recognised. Prevention focuses substantially on avoiding bites and controlling breeding sites, since the mosquito carries the virus between human hosts.
Q62. Which mosquito group is the principal carrier of dengue virus?
[UPPSC PCS Prelims 2022]
(A) Anopheles
(B) Aedes
(C) Culex
(D) Mansonia
Answer: (B) Aedes
Explanation: Female Aedes mosquitoes, especially Aedes aegypti, spread dengue through bites. These mosquitoes often breed in domestic water containers and tend to bite during daytime. Dengue is distinct from malaria, which is carried predominantly by female Anopheles mosquitoes.
Q61. In the 2022 polio drive, oral vaccine drops were administered to children below which age?
[RRB Group D, 20 September 2022]
(A) Five years
(B) Ten years
(C) Three years
(D) Two years
Answer: (A) Five years
Explanation: Pulse Polio rounds traditionally target children younger than five years to protect against poliovirus infection. Vaccinating this age group helps reduce the risk of paralysis and interrupt transmission. The strategy supplements routine immunisation and continued surveillance.
