NZ's Covid-19 statistics will become more accurate as the Ministry of Health starts reporting deaths where the virus is the underlying or contributing cause.

The Ministry previously recorded all deaths within 28 days of a positive test, plus any death that was attributed to Covid-19 after medical review.

The new reporting system shows the virus was an underlying or contributing factor to somewhere between two-thirds and three-quarters of deaths after a Covid-19 infection.

"It is good to see this upgrading of Covid-19 mortality reporting. New Zealand has followed the international reporting standard specified by the World Health Organisation which is important as it allows for meaningful comparisons across different countries and time periods,” says University of Otago Professor of Public Health Professor Michael Baker.

'However, this standard needs some revisions, which our Ministry of Health is now making.

'All health agencies and researchers want health statistics that are valid, i.e. that measure what they intend to measure. This change will therefore increase the confidence we have that deaths attributed to Covid-19 are valid. I am pleased to see that all of our Covid-19 mortality data will be revised to incorporate this change, including current and previously reported numbers.

'It is likely that reporting of Covid-19 deaths will continue to underestimate numbers. Covid-19 infection can cause death from heart attacks and strokes and other causes that may not be attributed to this condition.

'We know that deaths from other infections such as influenza have always been hugely underestimated. Only about 5 per cent of deaths linked to influenza have this infection recorded as the cause of death.

'This problem is partly because of the way that mortality reporting focussed on the underlying cause of death, so tends to default to any major chronic illnesses that a patient had, rather than acute infections that contributed to their death at that time.

'The Covid-19 pandemic is shining a light on the complexity of ensuing that health data are as valid as possible, and the need to keep improving our methods.”

Dr Bodo Lang from the University of Auckland Business School says that being more precise in the classification of deaths will be useful to illustrate the seriousness of Covid.

'As a side benefit, having this new classification will also be useful to address one of the criticisms from anti vaxxers and Covid doubters: how many deaths are really caused by Covid?” says Dr Lang.

'The evidence will now be clearer on this, possibly resulting in a reappraisal of Covid's seriousness by those who were least likely to follow Covid guidelines."

Immunologist Associate Professor Dianne Sika-Paotonu from the University of Otago Wellington says the spread of Omicron is continuing to place added burden and strain onto families, communities, our vulnerable, schools, workforces and our health and other support systems in New Zealand.

"Daily Covid-19 case figures remain high with hospitalisations continuing to increase, and hospitals, primary and community care overwhelmed, and with the actual Covid-19 community case figures likely much higher than those being reported currently,” says Professor Sika-Paotonu.

"About 100 Covid-19 related deaths have been reported each week over the past months – with sympathies and condolences respectfully extended to all family, whānau, kāinga, aiga and friends impacted and affected.

"Previously, Covid-19 associated deaths were reported in the daily Covid-19 updates as all those who'd passed away within 28 days of a Covid-19 infection.”

Professor Sika-Paotonu says now additional deaths associated with Covid-19 will continue to be reported in the daily updates, along with the total Covid-19 deaths being categorised based on whether Covid-19 is either the (1) underlying cause or a (2) contributing cause of death, and where these deaths can be wholly, or partly ‘attributed' to Covid-19. Another category will constitute (3) those deaths still under investigation.

"It has been indicated by the Ministry of Health that the median time taken between a death occurring and then being reported publicly is two days with approximately 10 per cent of deaths taking more than a week before being reported publicly,” says Professor Sika-Paotonu.

'The information relating to the majority of reported deaths will be processed by the Ministry of Health's Mortality Coding team usually within a couple of days, however incomplete death records, and those deaths referred to the coroner will take much longer.

"With more people having now been exposed to the virus, and with the emergence of the Omicron variant and subvariants, reinfections are increasing in a way not seen with earlier variants. Waning immunity, Omicron's higher transmissibility and ability to evade immune protection are contributing factors. The risk of reinfection remains, especially for vulnerable communities,” says Professor Sika-Paotonu.

"Ongoing work will be needed to understand more about whether re-infections for Omicron and all its subvariants are more or less severe, when compared to the primary infection. In the meantime however, it is still important that those who may have already had a Covid-19 infection, strengthen their immunity with vaccination/boosters as well.

Professor Sika-Paotonu says while issues with unequal global Covid-19 vaccine coverage, availability, accessibility and distribution persist, and remain unaddressed, new variants of the SARS-CoV-2 virus will continue to emerge, develop and spread.

'Addressing health inequities and current inequities in society will be critical steps moving forward,” says Professor Sika-Paotonu.

"There is still much work to be done at this time with significant immunity gaps in Aotearoa New Zealand right now.

Masks, Covid-19 vaccines and proper ventilation within the education setting remain important for protection, particularly for children, tamariki and tamaiki aged 5-11 years and those still needing to be vaccinated against Covid-19. Many adults also still need their Covid-19 boosters as well.

"During the Covid-19 pandemic, there has been limited exposure to other viruses such as the influenza virus here in Aotearoa New Zealand, and there is potential risk of upcoming influenza outbreaks moving into winter. We now have more of the influenza vaccines here in Aotearoa New Zealand being made available for people – these are important,” says Professor Sika-Paotonu.

Professor Sika-Paotonu says regular childhood vaccine schedules (non- Covid-19) for children tamariki and tamaiki in New Zealand have been significantly affected by the Covid-19 pandemic.

'As a result, there is potential risk of outbreaks for whooping cough, measles and other illnesses that could be prevented. A resurgence of influenza and the respiratory syncytial virus (RSV) could also possibly occur,” says Professor Sika-Paotonu.

"Although Covid-19 has been a key focus over the past two years, it is important to remember that all vaccinations are still important."