"A man who is a father of four once called me. He got the coronavirus first, followed by the kids and the grandparents. He asked if we could buy them masks as they had to wear them at home,"Zhang said. As a father himself, Zhang said he could viscerally relate to the deep guilt that engulfed the man. "He beat himself up for failing to insulate his family from danger. He also feels indebted for bothering me to help out."

When projecting the father's remorse on himself, Zhang is gripped by strong guilt and inadequacy. "The onus is on me to create a safe and easy living environment for the communities. It's my fault that I leave them distressed and exposed to danger," Zhang said.

"A resident asked me to give her health kits to needier neighbors as she said she had sufficient stocks," Zhang said. "Her gesture let me see how tight knit our communities are. People's altruism, empathy and mutual understanding empower me to stick by my work."

Since the whole city couldn't wrap its head around what's happening and how to contain the virus, Zhang has become somewhat neurotic about being infected. His chance of getting the virus is higher than the average resident, who stays at home and is cut off from the world. "An occasional sore throat, poor sleep, runny nose... make me nervous."

He lives with unease, particularly when he volunteered at testing centers and rapid testing was unavailable. "There was a time I suspected I got the virus. I went to test without my wife's knowledge. I didn't tell her until the negative result came out," Zhang said with a laugh.

He said he might not have gone this far were it not for his wife's unconditional encouragement. "She cooks my favorite and nutritious dishes to get me restored from burnout. She brews herbal teas to boost my immunity," Zhang said.

"Well, arguments also happen between us. I know we are both stressed out. So we don't take it personally."

Apart from the community-level social work, Zhang made suggestions on policies to streamline the pandemic control measures so as to find out root causes of the current dire situation and address them. He said he wants the residents' grievances to be heard.