Ottawa, March 19 : Theresa Tam, Canada's chief public health officer, has called for more people to get the booster dose against Covid-19 as the country has started easing restrictions, such as limits on social gatherings and mask mandates. Speaking at a press conference on Friday, Tam said that Covid-19 policies may soon shift from "an emphasis on requirements to recommendations" and that it's critically important that more people, especially for those 50 years of age or older, get a booster dose, reports Xinhua news agency. "We're in a period of uncertainty where the virus is still undergoing evolution, so getting up to date with vaccines and wearing a mask is really a good idea," she said, adding that it would be difficult to expand vaccine mandates to cover a booster dose because eligibility for the third shot varies and people with a previous Omicron infection have been told to wait up to three months between a positive test result and getting inoculated. According to a statement from Tam's office on Friday, recent studies indicated that an mRNA Covid-19 vaccine booster dose could enhance the overall immune response, which can provide longer lasting protection and possibly better effectiveness against variants. Over 5.2 million eligible Canadians need one or more doses to complete their primary series and many others are eligible to get a booster dose, the statement said. According to data released by the Public Health Agency of Canada, over 17.6 million third doses have been administered till date. National data has indicated that over 83 per cent of seniors aged 70 or older, 61 per cent of aged 50-59 years and 74 per cent aged 60-69 years have received an additional dose. The data indicated that over 81 pe rcent of the total population have been fully vaccinated. Age-specific vaccine coverage data, as of March 13, 2022, showed that over 88 per cent of people 12 years or older had at least one dose and over 84 per cent were fully vaccinated, while among children aged 5-11, 57 per cent had at least one dose. Health Canada on Thursday authorised the Moderna Spikevax Covid-19 vaccine for children 6-11 years of age. Following authorisation, the National Advisory Committee on Immunisation released recommendations for the use of Moderna Spikevax Covid-19 vaccine in this age group. /IANS