Local climate unlikely to drive the early COVID-19 pandemic

As per a study by researchers from PEI and as published in journal science, it shows that climate conditions may not have much impact in the current rate of COVID-19 infection. Even the importance of immunity system and resistance to climate change was highlighted by the researchers.

New Jersey: As per a study published in the Journal Science, local variations in climate are not likely to dominate the first wave of the COVID-19 pandemic. Some of the findings are:-

Climate conditions may not make a great impact in the current rate of COVID infection. This can be said as the researchers found that the vast number of people are still vulnerable to the strain of Coronavirus causing the pandemic -- SARS-CoV-2 -- and the speed at which the pathogen spreads.

"We project that warmer or more humid climates will not slow the virus at the early stage of the pandemic," said first author Rachel Baker, a postdoctoral research associate in the Princeton Environmental Institute (PEI).

"The rapid spread of the virus in Brazil, Ecuador, Australia, and other nations in the tropics and the Southern Hemisphere -- where the virus began during the summer season -- provides some indication that warmer conditions will be indeed do little to halt the pandemic", Baker said.

"Experience with other viruses suggests that, without a vaccine or other control measures, COVID-19 will likely only become responsive to seasonal changes after the supply of unexposed hosts is reduced", said co-author Bryan Grenfell, the Kathryn Briger and Sarah Fenton Professor of Ecology and Evolutionary Biology and Public Affairs and associated faculty in PEI.

The study was conducted by Baker and Grenfell along with the second author; Wenchang Yang, an associate research scholar in geosciences; Gabriel Vecchi, professor of geosciences and the Princeton Environmental Institute; and C. Jessica Metcalf, assistant professor of ecology and evolutionary biology and public affairs.

The study authors are all affiliated with PEI's Climate Change and Infectious Disease initiative.

However, a paper was published in December by the same team where they examined the impact of climatic condition leading to the annual T annual outbreaks of respiratory syncytial virus (RSV).

For the study in Science, the researchers ran simulations on how the pandemic would respond to various climates across the globe. Having been discovered in late 2019, COVID-19's response to warmer weather is not well known. The researchers instead ran three scenarios based on what is known about the role seasonal variations have on the occurrence of similar viruses.

• The first scenario assumed that the novel Coronavirus has the same climate sensitivity as influenza, based on a prior model from laboratory studies that highlighted the importance of low humidity to promote spread.
• In the second and third scenarios, the virus was given the same climate dependence and length of immunity as human Coronaviruses OC43 and HKU1, which are two causes of the common cold.
• In all three scenarios, climate only became a mitigating factor when large portions of the human population were immune or resistant to the virus.

This research also highlighted the fact more the immunity builds up, sensitivity to climate increases. The same may also apply to COVID-19 pandemic.