According to a new report, less than 3 per cent of 12-year-olds were fully vaccinated against human papillomavirus, which can cause cervical and other forms of cancer, during the 2020-21 school year, compared with about 60 per cent during the 2018-19 year.iStockPhoto / Getty Images
A new report shows just how steep the decline in vaccine coverage rates has been in recent years for some children in Ontario, one of the many consequences of the pandemic that experts say puts a large cohort of kids at increased risk for preventable infectious diseases.
The report, from Public Health Ontario, looks at the three most recently completed school years to determine how the pandemic affected routine administration of three vaccines, which are typically given in schools: hepatitis B, human papillomavirus (HPV) and the meningococcal conjugate (MCV4) vaccines. The vaccines protect against serious illnesses and cancers related to those viruses.
The report, published late last month, found that even with catch-up programs initiated by health officials to address pandemic-related drops, vaccination rates remain far below typical levels, putting many people at heightened risk of illness and disease.
“The systems that we use to deliver vaccines didn’t function properly during COVID,” said Shaun Morris, a clinician-scientist in infectious diseases at Toronto’s Hospital for Sick Children. “We’ve seen decreases in routine childhood immunizations in all ways.”
According to the PHO report, less than 3 per cent of 12-year-olds were fully vaccinated against human papillomavirus, which can cause cervical and other forms of cancer, during the 2020-21 school year, compared with about 60 per cent during the 2018-19 year. After a catch-up program in the following year, about 23 per cent of that same cohort were fully vaccinated, which means they received two HPV vaccines.
“Even with the catch-up, it’s still much lower than what we would have expected, based on pre-pandemic levels,” said Christine Navarro, public health physician with PHO who led the new report.
The report also shows that during the 2021-22 year, only 30 per cent of 12-year-olds had completed their hepatitis B vaccine series, given in two doses. During the 2018-19 year, completion rates were about 65 per cent.
Up-to-date immunization coverage with catch-up for school-based immunization programs among 12 year olds for the 2019-20 and 2020-21 school years in Ontario
Completed series by end of school year
Completed series one year later (catch-up)
Completed series two years later (catch-up)
2018-19 coverage for comparison
100%
79.1
80
60
52.4
50.8
37.5
40
36.3
23.4
20
0
2019-
2020
2020-
2021
2019-
2020
2020-
2021
2019-
2020
2020-
2021
Hepatitis B
HPV
MCV4
THE GLOBE AND MAIL, SOURCE:
PUBLIC HEALTH ONTARIO
Up-to-date immunization coverage with catch-up for school-based immunization programs among 12 year olds for the 2019-20 and 2020-21 school years in Ontario
Completed series by end of school year
Completed series one year later (catch-up)
Completed series two years later (catch-up)
2018-19 coverage for comparison
100%
79.1
80
60
52.4
50.8
37.5
40
36.3
23.4
20
0
2019-
2020
2020-
2021
2019-
2020
2020-
2021
2019-20
2020-
2021
Hepatitis B
HPV
MCV4
THE GLOBE AND MAIL, SOURCE: PUBLIC HEALTH ONTARIO
Up-to-date immunization coverage with catch-up for school-based immunization programs among 12 year olds for the 2019-20 and 2020-21 school years in Ontario
Completed series by end of school year
Completed series one year later (catch-up)
Completed series two years later (catch-up)
2018-19 coverage for comparison
100%
79.1
80
60
52.4
50.8
37.5
40
36.3
23.4
20
0
2019-20
2020-21
2019-20
2020-21
2019-20
2020-21
Hepatitis B
HPV
MCV4
THE GLOBE AND MAIL, SOURCE: PUBLIC HEALTH ONTARIO
For the MCV4 vaccine, which protects against four types of bacteria that can cause meningococcal disease, coverage was 43 per cent by the end of the 2021-22 school year, far less than the 2018-19 rate of around 80 per cent.
The report also included data on vaccination rates among 17-year-olds. While there were some minor dips in coverage rates, most of the teens in those cohorts would have received their routine vaccinations before the pandemic.
Dr. Navarro said there are high hopes that with the resumption of a more typical school year, rates of routine school-based vaccinations will start to return to a pre-pandemic level. During the first years of the pandemic, many public health staff were redeployed from doing routine childhood vaccinations and sending letters to families of children who had missed their shots and the return to these activities could help boost rates, she said. Dr. Navarro noted that Ontario has extended the eligibility of some vaccines to help ensure those who want to catch up are able to without being charged.
But Dr. Morris said there are lingering concerns about how to improve coverage rates in students who missed vaccines during the pandemic. Many of those children and adolescents have since moved to high school, where those vaccines aren’t typically given.
Low vaccine coverage rates means those individuals face a higher risk of disease as a result. For instance, HPV infections can lead to cervical and other forms of cancer in people who are unvaccinated. Meningococcal bacteria can lead to debilitating illness in young people and is often fatal, Dr. Morris said.
“Those going off to college are a classic risk,” said Dr. Morris, referring to meningococcal disease. “It’s entirely possible we’ll have people entering one of the highest risk parts of their life and not be properly protected.”
He said it will be up to health officials in Ontario and across the country to continue with catch-up programs and other novel efforts to raise coverage rates.
It’s also unclear the extent to which misinformation related to COVID-19 vaccines may be having a spillover effect.
“It’s really difficult to know the impact of, not just vaccine hesitancy, but vaccine fatigue,” Dr. Navarro said.
Dr. Morris said he fears that the rise of false information about vaccines does help explain why vaccination rates remain below pre-pandemic levels, even after accounting for catch-up programs.