Even the ever-optimistic and ever-composed Dr Fauci says that expecting a vaccine in 18 months is putting our hopes high. ( https://scroll.in/article/961746/dr-faucis-belief-that-well-have-a-covid-19-vaccine-in-18-months-is-optimistic-but-not-improbable ) Some European agencies are calling this period (when we have to live in this new-normal, without a vaccine) as the Covid-19 “echo period”. Echo period is a period that is going to last for sometime before the pandemic's last reverberations go down. Using masks and sanitizer and physical distancing are not the only things that need to be followed carefully. In this article, we briefly discuss an important issue that we need to be aware of during this echo period. This is regarding the air-conditioning systems we use in public and office places. Action Item : Minimize the use of wall/ceiling mounted split air-conditioner units in public/office buildings. Issues - When we say split AC here, we mean the systems which h...