The SNP MP for Paisley and Renfrewshire South was criticised in October after voting just five times since the snap poll in June.
But she blamed the Westminster requirement of constant travel for her failure to recover from persistent ill health in the summer months.
“This job takes a real toll on people, in every sense – emotionally, physically and mentally,” she said in an interview with Holyrood magazine.
“The constant travel is just a field day for bugs and germs. I was really unwell for a few months back there with stomach problems and I’m still getting tests but I literally couldn’t get out and about. Then I got the norovirus as well.
“I kept calling it the no-voter virus because I just couldn’t get into my work to vote. I wasn’t fit to travel and was given a medical line, etc, and yet the entire time I was getting sent dug’s abuse for not being in, not voting. Twitter, Facebook, email was full of it and it even crept into the workplace itself.”
Black, who famously became the youngest MP at Westminster since the 17th century, added: “At the Budget, one of the Conservative MPs across from me, who had been muttering through the entire thing, had a pop and said, ‘Oh how nice of you to join us, Mhairi’ with an irritating smug grin.
“I knew the other Tories could hear so I thought, no chance am I taking crap off this guy – his government is literally the reason thousands of people are dead. So, I said, ‘excuse me’ and he repeated himself, so I warned him that he should think very carefully about his next sentence which was, ‘They Work For you [a website that registers MPs’ voting activities], heard of it, Mhairi?’ so I boomed back, ‘Aye, and poor health, have ye’ heard of that?’ to which his face dropped, he went bright red and began profusely apologising and then his budget suddenly became conveniently interesting.”