Hello doctor, I'm aware of an earlier advisory on avoiding AC usage at home owing to the current COVID-19 pandemic outbreak and we are practicing the same too, so as an alternative, we plan to use an exhaust fan placing it in a way to blow the external cool air inwards of our apartment during night hours, please advise if this practice runs the risk of bringing in coronavirus infected air molecules into our home.. Furthermore, my apartment is three storeys above the ground level and there are no other building structures those surround us.. I await an early response from you in this regard. Thank you..