Severe respiratory illness rates are now the highest they’ve been in the last decade, mostly due to very high rates of flu.
This comes as ambulance services struggle to meet demand, and Health NZ urges people to save emergency departments for emergencies.
The SMC asked experts to comment. Please feel free to use these comments in your reporting or follow up with the contact details provided. Any further comments will be sent in a separate email.
Professor Michael Plank, School of Mathematics and Statistics, University of Canterbury, comments:
“After an unusually late start to the season, influenza levels have rocketed over the last few weeks and are now close to their highest level in 4 years. The last time influenza indicators were this high was 2022, which was the year of the post-pandemic rebound. This will be putting a lot of pressure on hospitals and GP practices around the country.
“With the very rapid rate of epidemic growth, it is possible we will even exceed the 2022 peak in the next few weeks before levels hopefully begin to come down as spring approaches.
“The good news is that this year’s vaccine formulation appears to be well matched with current strains. It’s definitely not too late to get a flu jab if you haven’t already had one this year and it will provide good protection against sickness.”
Conflict of interest statement: “No conflict of interest to declare.”
Dr Hannah Cooper, Public Health Physician, Health intelligence team at PHF Science, comments:
“Surveillance indicators monitored by PHF Science show that respiratory illness activity was very high in the week ending August 16th, reinforcing what has been reported by many front line health services.
“Severe acute respiratory illness (SARI) rates in the Auckland region were the highest we have seen since this reporting began in 2012.
“Primarily this is being driven by high rates of influenza-SARI, which are close to the high levels seen in 2022. What is different this year is that other respiratory virus activity is higher, particularly RSV and rhinovirus, contributing to the very high overall picture. All indicators suggest COVID-19 activity remains very low.
“Based on the subtyping data available, the predominant circulating strain is influenza A/H3 subclade K – this is the strain that caused a significant flu season in the Northern Hemisphere recently. The influenza A/H3 subclade K strain has evolved to be quite different to other influenza A/H3 strains that have circulated in recent seasons and so there is little natural immunity in the population, contributing to its high transmissibility. In the Northern Hemisphere season, there was no indication influenza A/H3 subclade K caused more severe disease at an individual level, however overall it contributed to a severe season due to the large numbers of cases.
“Importantly, the vaccine was updated ahead of our Southern Hemisphere season to better match influenza A/H3 subclade K, and data from the PHF Science virology lab to date indicate the circulating strains do match the vaccine.
“Even with a well matched vaccine, influenza can spread rapidly through a population as not everyone is vaccinated, and vaccination does not prevent all influenza infections. The primary goal of influenza vaccination is to protect people from becoming very unwell or dying from influenza, which is why they are funded in New Zealand for the groups most at risk of severe outcomes due to age or underlying health conditions. It is not too late to get a flu vaccine this year.”
Conflict of interest statement: “I have no conflicts of interest to report.”
Professor Michael Baker, Department of Public Health, University of Otago, Wellington, comments:
“Aotearoa New Zealand is experiencing a late season surge in influenza, which is well documented by a range of surveillance systems. As well as its direct effects on public health, this increase is also putting a large strain on health services.
“Clinicians are reported to be drawing on some Covid era measures in responding to the current surge, including separating patients with respiratory symptoms in general practice and taking additional infection control precautions in hospitals. While there is understandably little appetite for returning to the extraordinary measures used during the pandemic, there is value in considering what we learned from that experience and applying those insights to seasonal respiratory infections.
“One important lesson was the value of a clearly understood, graduated system for assessing the level of risk, identifying the responses appropriate at different levels, and communicating that risk consistently to the public and health services. The Covid-19 alert-level system was, of course, developed for a very different situation, but the underlying principle of linking changing levels of risk to progressively stronger measures still has value.
“At a baseline level, this approach could mean the usual measures of vaccination and staying home when unwell. As respiratory infection activity increases, additional measures could be considered, for example, mask use in healthcare and other higher-risk settings such as waiting rooms and public transport, and additional protections for particularly vulnerable groups, including people in aged residential care.
“Importantly, such a framework would not need to be limited to influenza. It could provide a routine way of communicating the combined risk from influenza, Covid-19, RSV and other significant respiratory infections, with the response scaled according to the level of activity and risk rather than requiring a pandemic before coordinated public communication begins.
“Aotearoa New Zealand already uses graduated systems to communicate changing risks from weather, fire danger and other hazards. The current influenza surge raises an important question: should we also have an ongoing, nationally understood respiratory-infection risk framework that tells people when the risk is low, when it is increasing, and what they can do to reduce transmission and protect themselves and those who are most vulnerable?”
Conflict of interest statement: “No conflicts to declare.”
Dr Ruth Semprini, Senior Clinical Research Fellow, Medical Research Institute of New Zealand, comments:
“We are seeing a very late surge in SARI this winter with overwhelming demand for health services. Our ED is currently always over capacity, with people waiting in corridors overnight, awaiting admission to hospital. Many of the admissions are related to influenza A.
“In order to cope, hospitals are cancelling planned surgeries and using those beds for emergency admissions from the emergency department.
“Transmission of all viruses is similar to what we all experienced in COVID. To minimise risk of these infections, it is important we do what we practiced during the pandemic – hand hygiene, avoiding public places if we’re sick and only returning to work/school once we are well.
“Healthcare services are working beyond capacity at present and it is likely we will continue to see these services strain until community transmission declines.
“If you haven’t been vaccinated against flu, please consider getting it. It may prevent a long wait in an ED corridor! ”
Conflict of interest statement: No declaration received.