UPSC Prelims 2023 Q67: Science & Technology – Health & Diseases
'Wolbachia method' is sometimes talked about with reference to which one of the following?
- (a) Controlling the viral diseases spread by mosquitoes
- (b) Converting crop residues into packing material
- (c) Producing biodegradable plastics
- (d) Producing biochar from thermo - chemical conversion of biomass
Answer: (a) Controlling the viral diseases spread by mosquitoes
Explanation
The Wolbachia method — fighting mosquito-borne viruses
| Detail | Fact |
|---|---|
| What is Wolbachia? | A natural bacterium found in about 60% of insect species |
| Mosquito targeted | *Aedes aegypti*, which normally lacks Wolbachia |
| Effect | Wolbachia blocks dengue, Zika, chikungunya and yellow fever viruses from multiplying in the mosquito |
| Spread | Infected females pass Wolbachia to their eggs, so it spreads through the population |
| Programme | World Mosquito Program (Monash University) |
| Results | Trial in Yogyakarta, Indonesia cut dengue cases by about 77% |
| India | ICMR–Vector Control Research Centre, Puducherry has developed Wolbachia-carrying Aedes strains |
Other options compared:
| Option | Real technology |
|---|---|
| (b) Crop residue to packing material | Mushroom-mycelium and pulp moulding |
| (c) Biodegradable plastics | PLA and PHA from microbes |
| (d) Biochar | Pyrolysis of biomass |
Answer: (a) Controlling the viral diseases spread by mosquitoes.
Why each option is right or wrong
- (a) CORRECT. Wolbachia bacteria in Aedes mosquitoes block dengue, Zika and chikungunya viruses.
- (b) Incorrect. Turning crop residue into packaging uses fungi or pulp moulding, not Wolbachia.
- (c) Incorrect. Biodegradable plastics come from microbes making PLA or PHA, not Wolbachia.
- (d) Incorrect. Biochar is made by pyrolysis of biomass.
Key point
Wolbachia method: release Aedes mosquitoes carrying Wolbachia bacteria, which block dengue, Zika and chikungunya viruses.
Remember
The Wolbachia method controls dengue and other mosquito-borne viruses.
Common mistakes
- Thinking Wolbachia kills mosquitoes; it mainly stops virus transmission.
- Confusing it with sterile insect technique, which releases sterilised males.
- Assuming it is genetic modification; Wolbachia is a natural bacterium.
Exam tip
Wolbachia makes mosquitoes poor virus carriers. Link it to dengue control.
Sources
- World Mosquito Program — Wolbachia method (worldmosquitoprogram.org)
- ICMR–Vector Control Research Centre, Puducherry
- Utarini et al. (2021), New England Journal of Medicine — Yogyakarta trial