The replies to Ontario Premier Kathleen Wynne on Twitter are not for the faint of heart. 

The tweets at Wynne predominantly express anger about her record and most stay within the bounds of fair comment, not crossing the line into personal abuse. Such calls as "Resign!" "You're incompetent!" and "Worst premier ever!" are now simply part of the deal for a politician in the era of social media. 

But Wynne also draws a significant number of abusive, sexist and homophobic tweets. A small sampling from just the past few days:

The comments on Wynne's Facebook page are equally nasty, but her communications team filters out posts that contain the most abusive words so the public can't view them.

A member of the premier's staff showed CBC News nearly 40 Facebook posts filtered out from just the past week, including ones calling Wynne a "wrinkly bitch" (by a Facebook user named George Onock) a "subhuman, dirty dyke" (Frank Yurkowski) and a "lying cheating c--t."

CBC News asked Wynne in a news conference on Tuesday about the online abuse.

"This isn't restricted to me or my colleagues, it's happening across the country," Wynne told reporters in Kitchener. "I don't read them all because it's just too toxic, but I read enough of them to know it's not who we are as Ontarians."

Wynne insisted she is "always an advocate for energetic political debate" and has a "very thick hide," but added, "I don't think it's helpful when factual conversation is overshadowed by personality and personal attack." 

Wynne said she believes most people find the online nastiness "unacceptable" and "don't want personal misogynist attacks to be part of the debate.

"The kinds of things we're seeing on social media undermine civility," Wynne said. "I think it discourages people from even entering politics."

She said any young woman seeing such online abuse would have to ask, "Why would I expose myself to that kind of personal attack?"

Several journalists have recently remarked on the extent of the vitriol against Wynne. 

Dealing with the online hatred poses a dilemma for Wynne's senior staff: they would like people to be aware of the extent of the abuse, but don't want to leave it posted for fear of appearing to condone it.

"It's good to pull the cover back on it," one of her senior officials said after CBC News raised the issue.

Wynne is by no means the only female Canadian politician to be the subject of online hatred. Violent Twitter and Facebook abuse against female politicians in Alberta, including Premier Rachel Notley, became a significant news story over the past two years. Conservative MP Michelle Rempel has also called out Twitter sexism. 

"Premier Notley has said that she's optimistic that we can turn that negativity," said Wynne. "I hope that's true, but it's going to mean that people are going to have to speak up." 

A spokesperson for Ontario NDP Leader Andrea Horwath says she faces a "steady stream" of sexist abuse on social media.

Horwath's communications staff run similar filters on Facebook to weed out abusive posts and will "block" users on Twitter who post "repeated abusive, denigrating, derogatory language," said the spokesperson. 

'War against women'

"It is truly a sustained war against women having power," said Megan Boler, a professor in the University of Toronto's department of social justice education. 

"The use of these kinds of terms and this kind of language reduces women to sexualized objects who are just known by their body part names," Boler said Tuesday in an interview.  

"The anger that gets directed at men, it simply takes a different form," she said. "It's generally more respectful."

Tamara Small, an associate professor at the University of Guelph, said social media provides a platform for people to launch sexist abuse.

"There's certainly a broader sexism that women working in politics are facing on a regular basis," Small said in an interview. "Women politicians have for years been criticized or treated in ways that their male counterparts haven't been." 

Small said online abuse makes politics look "rather inhospitable" to women.  

Internationally, Hillary Clinton faced a barrage of sexist online abuse during her presidential campaign in the U.S. In the U.K., Labour MP Yvette Cooper is leading a campaign called Recl@im the Internet directed at tackling online misogyny.

Last October, the Inter-Parliamentary Union released a report called "Sexism, harassment and violence against women parliamentarians" based on interviews with elected politicians from 39 countries.

Nearly 42 per cent of the women reported "highly contemptuous or sexually charged" images or comments about them spread through social media. "Over a period of four days, I received more than 500 threats of rape on Twitter," the report quoted a member of the European Parliament as saying. ​