Researchers have found that people living in higher altitudes, especially 3000 metres above sea level, reported a lower number of coronavirus cases than their lowland counterparts.
According to a study published in the journal Respiratory Physiology & Neurobiology on Monday, high-altitude environmental factors may contribute to reducing the virulence of novel coronavirus.
In order to carry out the study, the researchers examined the epidemiological data from Bolivia, Ecuador and Tibet.
According to the researchers, the Tibetan plateau region, comprising of Tibet, Qinghai and part of Sichuan, has a significantly lower number of cases in comparison to the rest of China.
“The impact of COVID-19 on the plateau region (of 9,000,000 inhabitants) has been drastically low compared to the rest of China,” the study stated.
“Indeed, only 134 confirmed cases were reported for the plateau region,” it added.
Examining the epidemiological data, the researchers also found that the number of COVID-19 cases was three times lower in the Bolivian Andes than in the rest of the country and four times lower in the Ecuadoran Andes.
The researchers claimed that the reason for the decreased severity of the global COVID-19 outbreak at high altitude could relate to both environmental and physiological factors.
A high-altitude environment is characterized by drastic changes in temperature between night and day, air dryness, and high levels of ultraviolet (UV) light radiation.
“In particular UV light radiation A (UVA) and B (UVB) are well known to be capable of producing alterations in the molecular bonds of the DNA and RNA, and thus UV radiation at high-altitude may act as a natural sanitizer,” the study said.
“In relation to SARS-CoV-2, while complete disinfection cannot be achieved by UVA and UVB, these radiations should shorten the half-life of any given virus,” it added.
According to a pulmonologist Clayton Cowl, prolonged exposure to altitude triggers a chain reaction in the lungs involving a protein known as ACE2 that might prevent pulmonary shunting, a problem common among COVID-19 patients.