Dear member / clinic,

Myocarditis and pericarditis post-vaccination

Attached is a letter from the Director General of Health on vaccine associated myocarditis and pericarditis. The Ministry has decided to improve the information it gives to patients about myocarditis and pericarditis following vaccination, and asks community vaccinators to do the same.

Key points:
  • Ensure patients / caregivers are informed of the risk and symptoms of myocarditis and pericarditis (and all known vaccine side effects, mild or severe, rare or common), verbally and in writing, and confirm understanding, prior to vaccination.
  • Advise to seek a doctor’s advice immediately if any of the symptoms listed below develop.
  • All vaccinators to review the IMAC webinar ASAP. The old version appears to have been withdrawn. A revised version with strengthened advice on myocarditis / pericarditis is “available soon” – check
Re: myocarditis
  • Myocarditis incidence in NZ estimated at 3/100,000 vaccinations
  • Myocarditis may be under-reported
Re: myocarditis and pericarditis COMBINED
  • Approximately equal incidence in males and females*
  • Approximately equal incidence after first and second doses*
  • Median age mid 30s*
Typical symptoms (NZ experience)
  • Chest heaviness, discomfort, tightness or pain
  • Difficulty breathing, shortness of breath
  • Feeling dizzy, light-headed or faint
  • Racing or fluttering heart, or a feeling of ‘skipped beats
  • Onset usually in the first few days following the vaccine but can occur in the weeks later.
*Please note per our previous communications that pericarditis generally affects older patients, M=F, while myocarditis is much more common in teenage males, with a male:female ratio of approximately 10:1.

The raw figure of 3/100,000 for myocarditis and pericarditis combined obscures the risk of myocarditis in teenage males.

We recommend particular care when advising 12-19 year old males and their parents / guardians about myocarditis, and monitoring post-vaccination.

HEPA air purifier selection tool
This tool allows users to choose a purifier based on desired number of air changes, room size, noise levels and cost, for different countries including Australia. Not all models will be available in New Zealand. A reminder that air purifiers can remove >99% of viral particles form room air; we strongly recommend their use in at-risk patient areas. New evidence continues to accrue in support of their use.

The first case was announced today in a Christchurch MIQ. Preliminary data indicate it is up to five times more contagious than delta, spreads very rapidly, and displays high levels of immune escape.

Data on its virulence are contradictory – some reports noting a 29% decline in hospitalisation rate, others claiming it is ‘mild’, and others that there is no reason to expect less virulence than delta. A summary of early findings from South Africa is copied below.

It remains to be seen how the virus performs in a country with low levels of infection-derived immunity and a high vaccination rate. Incidence of long covid remains a significant concern.

We recommend booster shots once available, and - even more important now given immune escape - close attention to combatting airborne spread per earlier emails, including:
  • Open doors and windows
  • Filtration via HEPA filter air purifiers
  • Minimise the duration of patient stays in the facility
  • Telehealth
  • Wear the best available mask – N95 or similar – and review advice on safe mask reuse.
With best wishes,

David Gollogly, Jasmine Mackay, Richard Chen, Kelvin Ward
Pandemic Response Subcommittee