Routine childhood vaccinations have fallen so dramatically globally during the COVID-19 pandemic that the World Health Organization and UNICEF are sounding the alarm.
Internationally, in 2021 alone, 25 million children will have missed out on life-saving vaccines. This is the largest sustained drop in childhood immunization in a generation.
In Aotearoa, New Zealand, we are seeing a similar worrying trend. The decline in childhood immunization resulting in low global coverage is now putting our tamariki (children) at real risk of preventable diseases, especially with national borders open again.
The country is not alone in suffering collateral damage to normal childhood immunization programs due to the COVID-19 pandemic. But while the decline may be worrying, all is not lost.
Risk of disease outbreaks
Immunization coverage at six months of age has fallen in New Zealand from a high of 80% in early 2020 to 67% in June 2022, and to 45% for Māori.
This is important because immunization coverage at six months is used as a marker for timely receipt of life-saving government-funded vaccines, including whooping cough (whooping cough), diphtheria, polio, pneumococcal disease and rotavirus.
For example, whooping cough (whooping cough), a particularly serious illness for babies, is a very real concern. Aotearoa has seen a resurgence of whooping cough every three to four years, meaning we have an increase in cases at a time when we also have low vaccine coverage.
Moreover, these declines in immunization coverage and subsequent risk of infection are especially important to consider now, as international travel increases.
NZ Ministry of Health, CC BY-ND
The return of the “old” diseases
Polio, a viral disease that can cause paralysis, disappeared from Aotearoa thanks to immunization, and the Western Pacific region was declared polio-free in 2000. As some parts of the world have yet to ‘eradicate, however, we still vaccinate children against polio.
A recent case in an unvaccinated young man in New York shows how the virus can travel and reemerge, even in developed, polio-free countries.
Read more: Diphtheria is back in Australia, here’s why and how vaccines can prevent its spread
Likewise, diphtheria is a rare but serious disease that causes breathing problems and can also lead to nerve paralysis and heart failure, with 5% to 10% of people with the disease dying.
Until widespread immunization after the 1940s, diphtheria was a common cause of death in children, and we haven’t seen it in Aotearoa for decades. But diphtheria has recently been detected in Australia in two unvaccinated children.
With New Zealand’s borders fully open since 31 July, we run the risk of these two “old” diseases being imported and causing problems for our under-immunized tamariki and their whānau.
A perfect measles storm
The major measles outbreak of 2019 serves as a warning. More than 2,000 people were infected and 700 hospitalized, with the highest number of cases in Auckland.
Fiji, Tonga and Samoa also saw outbreaks, with Samoa particularly devastated by more than 5,000 cases and more than 80 deaths, mostly in young children.
The severity of this outbreak could have been avoided because the combined measles, mumps and rubella (MMR) vaccine is highly effective.
Read more: The toughest phase of the Omicron outbreak is yet to come, but New Zealand may be better prepared than other countries
But childhood MMR coverage was not high enough at the time (nor has it been historically), leaving a known immunity gap between susceptible teenagers and young adults.
Since then, significant efforts have been made to close this gap in MMR coverage, although it has been eclipsed by the COVID-19 vaccination campaign.
The result is a potential perfect storm for another measles outbreak, with low MMR coverage globally and locally. Measles could ‘walk’ through New Zealand’s airports and encounter under-vaccinated tamariki and rangatahi (young people).
Prevention as a cure
There is good news, though. This year has seen the introduction of new initiatives to help manage waves of winter ailments, including government funding for flu shots for children aged three to 12.
This is welcome, as the flu crosses our border every year (except for 2020, when public health measures for COVID-19 were in place, including quarantine and wearing masks). As children are often considered super-spreaders, vaccinating children can reduce flu-like illness and related costs in both tamariki and their whānau.
But the message from the Director-General of the World Health Organization, Tedros Adhanom Ghebreyesus, remains urgent:
Planning and addressing COVID-19 should also go hand in hand with vaccination for deadly diseases such as measles, pneumonia and diarrhea.
In Aotearoa, New Zealand, the experience of vaccination against COVID-19 has also shown how Māori and Pacific community health providers can help achieve high vaccination targets, especially when combined with good outreach services, increasing vaccination providers beyond GP clinics and increasing the vaccination workforce.
But right now the statistics paint a worrying picture. Low childhood immunization coverage puts tamariki at risk of many serious and preventable diseases and adds a significant burden to an already strained health care system.
Prevention must be our highest priority. It is better than the best care, and it will protect the health care system from being overloaded so that it is available to those who need urgent care.