Structural racism in the health system, overcrowding and poorer overall health could see Māori die at rates 50 to 250 percent higher than other Kiwis in the event of a major coronavirus outbreak, experts say.
Their research was published Friday in the New Zealand Medical Journal, alongside a separate study which found "indigenous and minoritised ethnic groups" face racial discrimination in the health system, resulting in poorer outcomes.
New Zealand has so far only had 22 deaths from the global pandemic, with seven currently receiving hospital-level care. Of the 1757 confirmed and probable cases to date, only 9 percent have been in Māori - despite making up 16 percent of the population.
That disparity would quickly disappear in a widespread outbreak however thanks to the prevalence of "overcrowded and multi-generational households" many Māori live in, new research suggests.
"During the 1918 influenza pandemic, Māori death rates were seven times higher than those for New Zealand European/Pākehā," the Kiwi researchers, led by University of Canterbury and Te Pūnaha Matatini mathematics professor Michael Plank, wrote.
"As recently as 2009, during the H1N1 influenza pandemic, rates of infection for Māori were twice that of Pākehā, with increased severity."
SARS-CoV-2, the virus behind COVID-19, is clearly a different beast to influenza - its infection fatality rate (IFR) is somewhere between 0.5 and 1 percent according to most estimates, making it about 10 times more lethal than both regular flu and the 2009 variant, dubbed 'swine flu' - not to mention the ongoing effects some survivors are suffering months after their initial recovery.
It's hard to pin down the exact IFR for COVID-19 as, believe it or not, we're still likely in the early stages of the pandemic and it's not clear just how many people are infected, with not everyone who gets infected falling sick or even showing symptoms - yet they're still able to pass it on to others.
"Testing during an epidemic tends to focus on clinically severe cases, which may bias estimates of fatality rates upwards. Conversely, there is a lag time between onset of symptoms and clinical outcome, which may lead to underreporting of fatalities."
With New Zealand's case fatality rate - the number of deaths divided by the number of confirmed cases at 1.5 percent, this suggests around half of all infections in New Zealand to date have gone undetected.
Researchers did computer simulations of how the virus might spread through the New Zealand community, and how it could affect different ethnic groups based on socio-economic and health data from here and overseas.
Though COVID-19 overwhelmingly targets the elderly, and Māori on the whole are younger than other groups, they would still be more than 50 percent likely to die if infected, the study found.
"A report from the UK suggests black, Asian and minority ethnic groups are at higher risk from COVID-19 than white majority groups. Reports from the US suggest similar trends, where African-American communities are bearing a disproportionate health burden from COVID-19.
"These at-risk communities typically have higher prevalence of underlying health conditions, are more likely to live in overcrowded and multi-generational households, and have relatively young populations. Similar factors apply to Māori in New Zealand and this reinforces the need to account for the multitude of factors behind inequity, rather than crudely using age structure alone to estimate IFR."
Depending on how much of an influence underlying poor health is on mortality rates, Māori could die at rates up to 150 percent higher than Pākehā and other non-Māori/Pacific Islanders. Particularly at risk are rural Māori communities, which tend to be older.
"Although Māori and Pacific populations are structurally younger than other ethnic groups, they have shorter life expectancy and higher rates of premature death at all ages. Mortality rates for older Māori are shaped by their life course, which includes increased exposure to infectious disease and conditions affecting respiratory function.
"We also adjust for inequity in unmet healthcare need, which captures some of the structural biases and racism within the healthcare system."
Which brings us to the other study published on Friday in the NZMJ. University of Otago and Auckland researchers reviewed 24 previous papers looking at self-reported experiences of racism in the health system.
They found people who report being discriminated against are more likely to have poorer health outcomes.
"Racism operates at multiple levels with various pathways to health," the researchers, led by University of Otago's Dr Ricci Harris, wrote.
"These levels have been conceptualised by some scholars as internalised (or intrapersonal), interpersonal (personally-mediated) and systemic (structural or institutional).
"Internalised racism involves attitudes, beliefs or ideologies often founded on understandings of supposedly innate superiority and inferiority that may be held by members of dominant social groups and/or oppressed ones. Interpersonal racism refers to racism between people, with varying degrees of frequency and intensity, including manifestations from racially motivated assault to verbal abuse, ostracism and exclusion.
"Systemic, structural or institutional racism involves the production, control and access to material, informational and symbolic resources within societal institutions, laws, policies and practices."
They concluded that "racism is a determinant of health that has a negative impact across a broad range of health outcomes in New Zealand", and it was mostly targeted at "indigenous and minority ethnic groups".
"Now is the time for action in identifying and implementing policy initiatives/interventions to address the irrefutable negative impact racism has on health."