Gene Drives Transforming Malaria Control

Syllabus: GS2/ Health, GS3/ Science and Technology

Context

• Gene drive technology is emerging as a novel approach to genetically modify mosquitoes to prevent the transmission of Malaria.

Global burden of Malaria

• According to the World malaria report, there were 282 million cases of malaria in 2024, with an estimated number of malaria deaths standing at 610 000.
• The WHO African Region is home to about 95% of all malaria cases and deaths. Children under 5 years of age accounted for about 76% of all malaria deaths in the Region.

What are Gene Drives?

• A gene drive is a genetic engineering technology that biases inheritance patterns, ensuring that a specific gene is passed on to a disproportionately large share of offspring.
• It operates using CRISPR-Cas9, which enables precise modification and copying of genes during reproduction.
• Unlike normal inheritance where a gene has a 50% chance of transmission, gene drives can ensure inheritance rates exceeding 90%, allowing rapid spread through a population.

Tanzania ‘Transmission Zero’ Study

• Genetically modified mosquitoes significantly inhibited parasite development when fed on blood samples from infected individuals.
• In several cases, parasites failed to reach the infectious stage, thereby preventing transmission.

What are the Concerns?

• Scientific and Technical Challenges: The genetic diversity of malaria parasites requires multi-targeted interventions to prevent resistance. There is a possibility of evolutionary adaptation in both mosquitoes and parasites.
• Ecological Risks: Altering or suppressing mosquito populations may have unintended ecological consequences, as mosquitoes play roles in food chains and ecosystems.
• Regulatory and Governance Challenges: Deployment requires robust biosafety frameworks, risk assessments, and global cooperation.

What is Malaria?

• Malaria is a life-threatening disease spread to humans by some types of mosquitoes. It is mostly found in tropical countries. 
• Transmission: It is caused by plasmodium protozoa. The plasmodium parasites spread through the bites of infected female Anopheles mosquitoes. Blood transfusion and contaminated needles may also transmit malaria. 
• Types of parasites: There are 5 Plasmodium parasite species that cause malaria in humans and 2 of these species – P. falciparum and P. vivax – pose the greatest threat. The other malaria species which can infect humans are P. malariae, P. ovale and P. knowlesi.
  • P. falciparum is the deadliest malaria parasite and the most prevalent on the African continent. P. vivax is the dominant malaria parasite in most countries outside of sub-Saharan Africa.  
• Symptoms: Fever and flu-like illness, including chills, headache, muscle ache and fatigue.
• Vaccine: Since 2021, WHO has recommended broad use of the RTS,S/AS01 malaria vaccine among children living in regions with moderate to high P. falciparum malaria transmission. 
  • In 2023, WHO recommended a second malaria vaccine, R21/Matrix-M.

India’s Commitment and National Goals

• India remains steadfast in its commitment to eliminate malaria by 2030, with the intermediate target of zero indigenous cases by 2027. The strategic roadmap for this mission is guided by:
  • The National Framework for Malaria Elimination in India (2016–2030) outlines the vision, goals, and targets for phased malaria elimination.
  • The National Strategic Plan for Malaria Elimination (2023–2027) builds upon earlier frameworks and aligns with the WHO Global Technical Strategy for Malaria 2016–2030.

Source: TH