TORONTO -- As global demand for COVID-19 testing kits surges, Ontario has tightened its criteria for who is eligible for the tests.

On Thursday, the province’s Ministry of Health released new guidance for the health sector to follow regarding COVID-19 testing.

Under the new protocols, individuals who travelled outside of the country and are exhibiting symptoms of the disease will no longer be tested because of limited supply of viral nasopharyngeal swabs. These excluded individuals have been defined as “probable” cases under the province’s guidance.

According to a notice posted on its website, the government agency Public Health Ontario states there is an “increased global demand” for the swabs due to the COVID-19 pandemic.

As a result of the limited supply, the province will be reserving testing for vulnerable groups.

“In an effort to maintain capacity and make better use of supply, and in recognition that anyone travelling outside of the country is being asked to self-isolate for 14 days, we’re prioritizing those individuals without travel history with symptoms,” Travis Khan, the communications director for Health Minister Christine Elliott, said in an email to on Saturday.

Individuals who are still eligible for testing include people with symptoms who are contacts of confirmed cases, those who have been admitted to hospital with acute respiratory illness, health-care workers with symptoms or who are part of an investigation into an institutional outbreak, people living in long-term care homes and retirement homes, and First Nation community members living on reserve.

“Testing outside of these recommendations based on public health and clinical judgement can be made in consultation with local public health officials,” the guidance states. “As this goal is for prioritization of those that are at highest risk, this… decision should be made by exception.”

Dr. Brian Conway, an infectious diseases expert, said the shortage of test kits needs to be addressed immediately in order to track the spread of the virus.

“It underscores the urgent need for us to have enough tests available to formally test everyone who has any symptoms or any risk of COVID-19,” he told CTV News Channel on Saturday. “This is really the only way we will completely understand what’s happening in the epidemic in Canada and make the most informed decisions possible.”

Khan said the province is working to procure more testing kits.

“We expect to return to expanded testing as soon as we’re confident in stable supply. To do so, we’re actively working with our manufacturing and supply chain partners to procure additional test kits,” he said.

Until then, individuals who are no longer eligible for testing have been advised to self-isolate or go to hospital if their symptoms significantly worsen, such as shortness of breath.