Data from the World Health Organization indicates the Omicron BA.5 variant is now responsible for the majority of COVID-19 cases around the world, with global infections on the rise again and spreading through Canada.

With some provinces reporting they have already entered a seventh wave, many Canadians are wondering when they can get their next booster shot.

Canada's National Advisory Committee on Immunization (NACI) issued interim guidance at the , saying "a fall booster dose in advance of a potential future wave of COVID-19 will be most important for older adults and other populations at increased risk of severe COVID-19 disease, regardless of the number of booster doses previously received."

While doctors are strongly recommending additional doses as protection wanes, there is debate among experts on the timing and whether to wait for newer versions of the vaccine that may be more effective against Omicron and its subvariants.

CTVNews.ca takes a look at who is currently eligible for a second booster shot or fourth dose by province and territory.

BRITISH COLUMBIA

The province says invitations for the next booster are to seniors aged 70 years and older, Indigenous people aged 55 years and older, and those who have underlying medical conditions or are clinically extremely vulnerable. Individuals in long-term care and assisted living have already been offered their next dose.

The province plans to offer a fall booster dose to everyone 12 and older, citing recommendations from NACI, and says it will send out personalized booking invitations this fall.

Appointments can be made through local pharmacies and health authority clinics.

The province's call centre at 1-833-838-2323 is available daily from 7 a.m. to 7 p.m. local time for those who may need help booking an appointment.

Phone agents cannot respond to questions asking for advice around the best timing for your next dose, the website says.

B.C. residents can register to stay informed on when it will be their turn to book an appointment.

ALBERTA

As of , all adults in Alberta can receive a fourth dose of a COVID-19 vaccine.

Albertans can register and online or call Health Link at 811 if at least five months have passed since their third dose.

The province recommends those who have had COVID-19 to wait at least three months before getting their booster.

SASKATCHEWAN

Residents can receive a of a COVID-19 vaccine four months after their last dose.

For those who are over the ages of 50 and , a second booster is available three months after receiving the first booster dose.

For eligible First Nations and Metis communities and the Northern Service Administration District, appointments can be made through 1-833-SASKVAX (727-5829) only.

Residents can book through , in targeted communities, and those without access to a nearby pharmacy can book through the province's .

MANITOBA

Residents aged , Indigenous people aged 30 and above, those who live in a care home in congregate settings, and Manitobans aged 18 and older with moderate to severe immunocompromised health .

Booking can be made or by calling 1-844-MAN-VACC (626-8222) Monday to Friday 9 a.m. to 5 p.m. local time to make an appointment.

ONTARIO

Ontario expanded eligibility for fourth doses to on July 14, as long as they received their first booster at least five months ago.

While the province has opened up the availability to adults, Chief Medical Officer of Health Dr. Kieran Moore said the second booster is "not absolutely necessary" if individuals have or face personal circumstances that would benefit from additional protection.

Healthy adults may want to wait until the fall when a bivalent COVID-19 vaccine may be available, he said. A bivalent vaccine is one that works against two different antigens, in this case a COVID-19 vaccine that is also tailored against the Omicron variant.

Residents can or by calling the at 1-833-943-3900. Ontarians can also book directly through local public health units that have their own booking systems, at or through Indigenous-led vaccination clinics.

QUEBEC

Everyone aged 18 and older can now get a second booster dose of an mRNA vaccine in Quebec if at least three months have passed since their first booster, .

For those aged 12 and up who are on dialysis or whose immune systems are compromised, a second booster can be administered if at least three months have passed since receiving their initial booster shot.

Residents can for an appointment, , or call 1-877-644-4545.

NEW BRUNSWICK

The province for fourth doses beginning July 12 to anyone , if at least five months have lapsed since their first booster.

Indigenous people aged 12 and up can also get their second booster if at least five months have passed since getting their first.

Residents can online with a pharmacy or clinic, by calling 1-833-437-1424, or emailing vbn@gnb.ca.

NOVA SCOTIA

Residents can get a second booster 168 days, or about five and a half months, after the first booster shot. However, the province's public health recommends waiting until the fall.

Those who are aged 70 and older can get a fourth shot 120 days, or four months, after getting their third dose.

Those who are 18 and older living in long-term care or congregate settings with seniors, Indigenous people who are at least 55 years old, and immune compromised individuals between 50 and 69 can also get a second booster if it has been at least 120 days since their first booster.

Residents can book their appointments , go to a or , or call 1-833-797-7772.

PRINCE EDWARD ISLAND

Prince Edward Island is offering fourth shots to everyone who is 12 and over and who received their first booster at least six months prior.

The province "especially" recommends to get a second booster.

Residents can book online through the , with participating , or by calling 1-844-975-3303.

NEWFOUNDLAND AND LABRADOR

Starting July 20, those who are aged can receive a fourth dose.

Those who have compromised immune systems, live in a group setting such as long-term and community care homes, and Indigenous people aged 18 years and older are also eligible.

At least 20 weeks must have passed since receiving your first booster shot.

Appointments can be made depending on the health region.

YUKON

On the recommendation of Yukon's chief medical officer of health, the territory expanded its eligibility for second boosters on July 13 .

To be eligible, residents must have received their first booster at least six months ago, or have tested positive for COVID-19 at least three months ago.

For more information, visit Yukon's . To book appointments, visit the or call 1-877-374-0425.

NORTHWEST TERRITORIES

Everyone who is who had their first booster shot six months ago can now get their second booster shot.

Those who are at least 12 years old with serious underlying health issues can also get a second booster.

Those living in Yellowknife can make an appointment on the . Booking outside Yellowknife requires a call to a .

NUNAVUT

Currently, anyone in Nunavut can receive a fourth dose of a COVID-19 vaccine.

Those wanting to get a second booster are asked to wait after receiving their last dose.

Questions about vaccines can be made by calling the territory's COVID-19 hotline at 1-888-975-8601.

With files from CTVNews.ca Writer Michael Lee