Climate change and Virus

Climate change and Virus

Subject – Environment

Context – zika virus outbreak

Concept –

• In the years that immediately followed the first case of Zika infection in 1952, the disease was endemic to tropical and subtropical regions. The global rise in surface temperature due to climate change pushed the virus into colder reaches of the country.
• The vectors of the virus — Aedesaegypti and Aedesalbopictus mosquitoes — are ectotherms. This means the body temperature is regulated by their habitat — the warmer the surroundings, the warmer it is within the host body.
  • The suitable range for the transmission of the Zika virus is 23.9-34 degrees Celsius.
• In a worst-case global warming scenario, where greenhouse gas (GHG) emissions are not reduced, over 1.3 billion new people will be exposed to Zika by 2050.
• The world is not on track to keep warming within 1.5°C over pre-industrial levels, and global temperature rise can cross 2.4°C by the end of this century despite pledges made at the 26th Conference of Parties (CoP26) to the United Nations Framework Convention on Climate Change.
• The higher global temperatures can accelerate evolution of the pathogen and vector, apart from widening the range of transmission.
• Aedes mosquitoes breed in small pools of water. Thus, heavy and frequent rainfall due to climate change can result in higher transmission rates.
• The virus can also flourish during droughts in water storage containers — a correlation seen during the outbreak in Latin America.
• Precipitation patterns upset by climate change thus fuels the spread of the Zika virus previously untouched by the infection.