Warmer weather is unlikely to significantly impede the spread of the novel coronavirus, a National Academies of Sciences (NAS) panel told the White House on Tuesday.
About a dozen members of the Academies’ Standing Committee on Emerging Infectious Diseases and 21st Century Health Threats published the report, addressed to Kelvin Droegemeier, head of the White House’s Office of Science and Technology Policy.
Their report found that while studies of how temperature and humidity affect the virus’s transmissibility are not yet clear, previous research suggesting a connection were flawed.
“There is some evidence to suggest that [the coronavirus] may transmit less efficiently in environments with higher ambient temperature and humidity; however, given the lack of host immunity globally, this reduction in transmission efficiency may not lead to a significant reduction in disease spread” without efforts such as social distancing, the report states.
No such seasonal aspect has been observed in other coronaviruses such as SARS and MERS, the report noted.
The report found various issues with data quality in existing research including the “estimates of reproductive rate, assumptions about infectivity period, and short observational time windows.” It also found they failed to account for factors like geography, per capita income, access to testing and the quality of local health care systems.
Both President Trump and Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, have suggested warmer temperatures may slow the spread of the virus, although Fauci has noted that without effective mitigation, another outbreak could occur in the fall.
“I think it very well might,” Fauci said, when asked in March whether the virus could have a seasonal cycle. “And the reason I say that is that what we’re starting to see now in the Southern Hemisphere, in southern Africa and in the southern hemisphere countries, is that we’re having cases that are appearing as they go into their winter season.”
The NAS cited similar cases, noting, “Given that countries currently in ‘summer’ climates, such as Australia and Iran, are experiencing rapid virus spread, a decrease in cases with increases in humidity and temperature elsewhere should not be assumed.”