Jeannette Hinkle and Zane Razzaq Daily News Staff FRAMINGHAM — In a development that leaves a huge hole in the city's fight against the coronavirus, Director of Public Health Sam Wong confirmed he is taking a medical leave. “I’m exhausted,” Wong told the Daily News by phone on Wednesday. “I’m physically, mentally and even sometimes spiritually exhausted. I have given everything I’ve got for the city for the past 10 months and then some, and it has taken a toll on my health and it is to the point where I have to take a step back.” Wong's last day is Thursday. He said he will be on leave for the foreseeable future. Others, though, say he has essentially resigned his post and isn't expected back.