Modelling presented to the Government shows New Zealand continues to face a "major challenge" in avoiding tens of thousands of deaths from COVID-19, the Health Minister has warned.
Speaking to the special Epidemic Response Committee, which was established to hold officials to account for their response to the COVID-19 outbreak, Dr David Clark touched on modelling which has informed the Government's decisions over the last two months.
Dr Clark told the committee that modelling didn't provide a prediction, but showed the serious threat the virus could have, both checked or unchecked. A University of Otago paper released publicly on Tuesday said New Zealand could see 14,000 deaths if no significant action was taken. Dr Clark said the death of tens of thousands of people would be "totally unacceptable".
Among the raft of measures the Government has imposed in order to try and prevent that situation is the border closure as well as the nationwide lockdown that came into force last week. The lockdown is meant to reduce contact between people, therefore limiting the potential for community transmission.
However, Dr Clark said we still face an uphill battle.
"The truth is that based on the modelling and what we have seen in other countries and territories, including those that have taken very significant measures, we continue to face a major challenge to avoid tens of thousands of deaths," the Health Minister said.
Dr Clark provided two scenarios with different degrees of success in reducing contact between people.
"If we assume, that each person who contracts COVID-19 passes it on to an average of 2.5 people and we manage to reduce contact within the population by just 25 percent for six months, we could still see more than 1.1 million cases and 12,700 deaths," Dr Clark said.
"If we assume the same level of infectiousness… but we manage general contact reduction of 50 percent for nine months, the number of cases drops by a quarter of million and the number of deaths might fall by 4000."
Both scenarios are considered in the University of Otago paper. It says that the 50 percent contact reduction wouldn't quite push the peak of cases out until when a vaccine may be available, but would "allow for time for improved health system organisation and treatments to be identified", meaning fewer hospitalisations and deaths.
The 25 percent reduction, however, would have "very major impacts on health services".
"These levels of demand would be completely unprecedented for New Zealand, which has a secondary care sector with very little surge capacity," the paper says.
"The filling up of all ICU beds in the country at a very early stage of the epidemic curve, would mean that the case fatality risk would probably increase (with some signs of this occurring in Italy in March 2020 from the pandemic there)."
Dr Clark said intensive measures may need to be in place for some time, but also noted that doesn't mean the country will necessarily stay under a lockdown at alert level 4. Instead, domestic restrictions may be loosened while maintaining strong border measures until other countries contain the virus.
Currently, the lockdown is meant to last for four weeks, but the Prime Minister hasn't ruled out extending it if community transmission is still happening. The lockdown could be applied to just some regions of the country still combatting the virus.
Several papers from both New Zealand and overseas have suggested that intensive measures may be required until a vaccine is developed, which is between a year and 18 months away.
"The major challenge of suppression is that this type of intensive intervention package - or something equivalently effective at reducing transmission - will need to be maintained until a vaccine becomes available (potentially 18 months or more) - given that we predict that transmission will quickly rebound if interventions are relaxed," a paper from the Imperial College of London says.
Unless the virus is eliminated from the country or vaccinated against, relaxing the lockdown may lead to another spike in cases, which if not properly managed with the ramping up of restrictions, could overwhelm the health system.
