Asia Pac J Public Health. 2020 Jul 25:1010539520944725. doi: 10.1177/1010539520944725. Online ahead of print.
There is a huge disparity between the mortality from COVID-19 in developed Western countries and developing Asian countries. Low viral load in the nasal cavity due to open air ventilation is a plausible reason for this difference. The transmission of SARS-CoV-2 occurs through respiratory droplets and fomites. There is ample evidence that the virus is airborne as well. The biggest factor in the transmission of SARS-C-V-2 are asymptomatic or paucisymptomatic carriers. Lack of open air ventilation is a major compounding factor as the virus remains in the environment, especially on fomites, leading to regular and repeated exposure to the virus. As a result, people living in developed countries tend to build up high viral load in their nasal cavity and nasopharynx. Studies have clearly shown that the severity of COVID-19 is directly proportional to the viral load harbored in the upper respiratory tract. These factors indicate a strong association between high viral load and poor ventilation, which, in turn, leads to high mortality from COVID-19 in developed Western nations.