York Region announced this afternoon that only the roughly 600 people in line at each of its two H1N1 clinic locations – 1 Villa Royale Ave. in Vaughan and 100 Eagle St. W. in Newmarket – will get the vaccine today.

The cut-off was made because it was determined it would take until the 8 p.m. closing to get all the people in line vaccinated, the region said in a news release. People showing up now are being told to return to the clinics when they reopen at noon Thursday. They are welcome to line up earlier.

The two York Region clinics will be open over the weekend, with a third clinic – at Sutton Kin Community Hall, 3 Fairpark Lane in Sutton – opening Monday. Additional new clinics are planned.

Meanwhile, Dr. Barbara Yaffe, Toronto's associate medical officer of health, confirmed an outbreak of H1N1 at Mount Sinai Hospital at a press conference this afternoon.

Yaffe also said there is an increase of absenteeism in about 40 schools in Toronto, at which 15 are known to have an increase in influenza activity.

"The number of cases in Toronto is increasing significantly," said Toronto chief medical officer David McKeown .

There have been 115 confirmed cases of H1N1 since the beginning of September; 68 of those were reported last week.

That represents just the tip of the iceberg since most people are not being tested for the virus.

The City of Toronto is opening only two vaccination clinics tomorrow, not 10 as widely believed.

The two clinics are for priority groups only. They will be at the North York and East York civic centres. They will be followed by additional clinics for priority groups on Friday and Saturday. See Toronto Public Health's website for more information.

The entire complement of 10 clinics will open to the general public on Monday.

View a list of all GTA clinic hours and locations.

Find everything you need to know on our H1N1 page.