OTTAWA/GENEVA (Reuters) - Canada, which has reserved enough doses to vaccinate residents against COVID-19 several times over, is in talks with other governments about a plan to donate shots to lower-income countries, according to three sources familiar with the matter.Canada has made deals to buy more doses per capita than any other nation, according to researchers at the Duke Global Health Innovation Center in North Carolina. It is among a handful of wealthy nations that reserved billions of doses between them before late-stage trial data came in, ensuring they would get access even if only one or two vaccines worked. Canada could donate extra doses through the World Health Organization-backed COVAX facility, which would distribute them among recipient countries, said a Canadian government source. Separately, a COVAX source confirmed discussions were going on between Canada and other governments and organizations involved with COVAX, a facility created to ensure equitable access to COVID-19 vaccines.