Covid-19 cases in the community are likely to be two to three times the number reported by the Ministry of Health each day, says University of Auckland epidemiologist Professor Rod Jackson.
That's because testing capacity is stretched and undiagnosed cases will be mounting as Omicron takes hold across New Zealand.
A record 6137 community cases and 205 hospitalisations were reported this afternoon, shortly after Covid Response Minister Chris Hipkins announced that NZ will move to phase 3 of the Omicron response plan from midnight tonight. The death of a person with Covid-19 was also reported.
In a live Q&A with NZ Herald Premium subscribers this afternoon, Professor Jackson covered the use of RATs, boosters for kids, classifying Covid-related deaths, rules for travellers - and a whole lot more.
Here are some highlights from the discussion:
Gary P: What's the likely real rate of current daily Covid infections (not just the tested/confirmed cases)?
RJ: Probably two to three times the number. It is more useful to look at the hospitalisations which are the important tip of the Omicron iceberg.
Glenn R: Why can't we obtain Rapid Antigen Tests easily and affordably? It would seem to be a no-brainer to have people self monitoring and self diagnosing particularly as the newer tests available have higher rates of accuracy e.g. 98% for one I read of.
RJ: RAT sensitivity (ability to identify infections) varies a lot depending on the test itself, when it is done and who does it. So they can often miss an infection and falsely reassure people that they don't have Covid-19. That's why they have not been made widely available until now. When you have the capacity to do PCR tests, they are a much better option because they are much more accurate than RATs and every case is documented. However, we no longer have the capacity to do sufficient PCR tests and RATs are better than no test. So it would be great to have them more widely available now.
Brendan S: I've been struggling to find any MOH info on how many of the 56 deaths [of people infected with Covid-19] were a result of underlying health conditions? The 'unknown' component would be useful as well, as some of these may be underlying health conditions also but families don't wish this information to be reported.
RJ: It is irrelevant whether people who die from Covid-19 have underlying conditions because most people who die have underlying conditions. If Covid precipitates a death earlier than it would have otherwise occurred, that death is caused by Covid. All we ever do is prolong life, we cannot prevent death. More than one-third of middle aged and older adult New Zealanders have underlying conditions. Most health professionals spend most of their time addressing the health issues of people with underlying conditions.
Bindi M: We're told getting 'boosted' is the best thing to do to protect ourselves in this Omicron surge. But under-18s aren't eligible so my teens, vaccinated well over 6 months ago, are facing the surge with waning protection from the first 2 doses. Granted the benefit may not be as clear as in older ages but the USA and others recommend boosters for ages 12+. Is there any good data that teens' immunity wanes less than those over 18yrs? Or greater risk from boosters vs doses 1 & 2? Why is this group being ignored here when they have big risks of exposure every school day?
RJ: We get vaccinated to protect ourselves and the community. As all vaccines can have side effects, It is always a balance between benefits (for individual and communities) and harms (to individuals). Younger people are less likely to have severe disease when infected with Covid so the balance of benefits and harms is always going to be less clear. That's why younger people have been the last ones to get vaccinated or boosted. The evidence is now increasingly clear on the balance of benefits and harms in younger people, so I would support boosting the 12+ group.
Peter M: Can we assume that because the vaccine doesn't prevent you from getting Covid and we are over 90% vaxxed that the hospitalisation figures will actually show up with a majority of vaxxed patients?
RJ: The vaccine, particularly three doses, significantly reduces the risk of getting Covid each time one is exposed to an infected person. So it has a very important role in slowing down the spread of Covid and it is the speed of spread that overwhelms hospitals and businesses. However, if you keep on getting exposed to an infected person you could still get Covid. You are correct that as most people are now vaccinated, most hospital cases will be vaccinated people. Nevertheless, in January this year, unvaccinated kiwis were 10 times more likely to be hospitalised than vaccinated Kiwis.
Peter M: Is it true that many people die of other health issues but happen to have Covid [and are] therefore labelled as a Covid death?
RJ: See my reply to Brendan S regarding people with underlying conditions. Also the way we report deaths in New Zealand and elsewhere is to classify the main cause of death. So, it is more likely that we will under-report than over-report deaths caused by Covid-19. Worldwide the true number of deaths caused by Covid is three to four times the officially reported number of about 6 million.
Peter M: When someone dies we always get a standard response from MOH saying there is no comment and the family wishes for privacy. We don't need to know who died but being a bit more upfront about the actual death and health condition would be helpful. Surely MOH can publish the real facts surrounding deaths without disclosure or identifying individuals?
RJ: This is done to protect the privacy of individuals and families. However, as I point out in my reply to Brendan S, I think the presence of an underlying health condition is irrelevant. If someone dies before they otherwise would have because of Covid-19, that is a death caused by Covid.
John Brian J: A week ago Dr Nick Coatsworth, former deputy chief medical officer in Australia, stated that Omicron was no more dangerous than flu (which I note typically kills about 500 NZers a year), and that boosters and masks were unnecessary, especially for school children. Why is this advice ignored?
RJ: Unfortunately he has missed the main point. Flu has an R-value of less than 2. This means that on average one person with flu infects fewer than two other people. The R-value for Delta was 6 and for Omicron it is much higher again. It is the speed of spread which overwhelms GPs, hospitals, schools, businesses etc. You CANNOT compare Omicron with flu. It's apples and potatoes (not a mistake - oranges are too similar to apples to be the appropriate analogy). His advice was ignored because unfortunately he got it wrong.
Nihal F: If I have taken my second dose in December, would that still not provide me adequate protection? If no, how does a two dose structure work well for Delta which is more deadly but cannot work for Omicron which is milder? Waning immunity should not be a factor since it's under three months since my second dose?
RJ: Your two doses gives you good protection against severe disease and death, but its protection against infection (not severe disease) weakens over time. Right now your protection against infection has dropped to about 30% compared to being unvaccinated. That means that if you and a similar unvaccinated person are exposed to someone with Covid-19, you are 30% less likely to be infected each time you are exposed. If you get boosted that protection increases to about 70% and you also get some extra protection against severe disease. We now believe the this should always have been a 3 dose vaccine.
Zoe H: Are you aware there are vast tracts of NZers who are not scanning in deliberately to avoid the close contact isolation risk? The same group of people are staying home when sick, keeping their heads down treating it like any normal cold. I know this as we have a nationwide business, with approx 1500 customers across the entire breadth of the country. This is what nearly all of them are telling us, unsolicited. For me this is the really interesting point. In our small industry alone is seems to be quite prevalent, so it must be widespread, yet I've seen or heard nothing of it in the media.
RJ: I have heard the same thing. In phase 3, you are only expected to isolate if you have Covid or are a household contact of an infected person. So there is no downside to scanning. In fact it is more important than ever because we are now being asked to inform our contacts if we are infected. Scanning is the best way to remember where we have been. So please start scanning again. I think it is a good idea that people are staying home if they have Covid symptoms, but they should really get a test. Also, with the increasing availability of RATs, people shouldn't have to wait so long to get tested.
Stuart B: Kia ora, we read stories of "otherwise fit & healthy" people who are hospitalised from Covid. Where can we find that breakdown % and by age group, etc? If not why not? Thanks.
RJ: The information is not available. This is partly because it is impossible to define 'otherwise fit and healthy' in any meaningful way. Obesity, diabetes, high blood pressure and asthma are just a few of the 'so-called' underlying conditions and depending on the definitions used, between one-third and one-half of middle aged and older adults would meet the criteria, making it rather useless information. Also, what would you want to do with this information?
Moderator N: My son's at a high school that's had multiple Covid cases (students and staff), including in his year group. He's not a close contact though, so is able to go to school. He's vaxxed, wears a mask etc, and he really wants to be at school, but we feel like it's only a matter of time before he's exposed. What would your call be in this situation? Thanks.
RJ: He is doing all the right things which is great. He may very well get Covid sometime, but by being vaccinated and wearing a mask, he is significantly reducing his personal risk of severe disease and supporting New Zealand by helping slow down the spread of Covid, because vaccinated people are much less likely to get infected than unvaccinated people each time they are exposed. My advice would be to encourage him go to school.
Jo B: Can you explain how asymptomatic nurses with Omicron can work because of a nursing shortage but an unvaccinated nurse without Omicron cannot?
RJ: I am unaware that asymptomatic nurses with Omicron are allowed to work.
Jill B: What are the parameters for admitting someone to hospital once they test positive for Covid or sending them home? With all the restrictions being justified by not overwhelming the healthcare system I would like to know is this even likely to happen or it's more govt spin.
RJ: I don't know the exact parameters, but almost every health system worldwide (including in Australia) has been overwhelmed by Omicron. It's not government spin. Omicron spreads so quickly that no health system can cope without doing everything we can to slow it down.
Amber B: Interested to know when people are ICU/HDU, does this mean they're ventilated? Would be good to get a feel for how sick you need [to be]/what treatment you're getting to go into ICU/HDU when these numbers are reported.
RJ: I can't provide details of who gets admitted to ICU, because the criteria differ from hospital to hospital. Clearly ventilated patients require ICU admission. However most Covid cases, including severe cases, can be managed outside of ICU with the appropriately trained staff and isolation facilities. The main treatments are oxygen and steroids which don't require people to be in ICU.
Jacqui B: Each year the flu vaccine is altered depending on the dominant strains around. Has the Pfizer vaccine or any other vaccines been modified in a similar way since 2020 to include the new variants such as Delta and Omicron? If not, why not?
RJ: Good point. Updated Pfizer (and equivalent) vaccines have been developed and are being tested now. There are also many laboratories worldwide working on new, more effective and more long lasting vaccines. Our current vaccines are much better than we ever expected but we can look forward to even better ones.
Kathy B: Hi Professor Jackson. Thanks to Mr Jenner we now have vaccines, & mostly eliminated Smallpox. Did this virus not mutate in the same way as Covid 19 & subsequent variants? What's the big difference? Thanks in advance.
RJ: There are a number of reasons why smallpox has been eliminated but not Covid-19. Check out [this article in The Conversation]. But to answer your specific question, smallpox does not mutate anywhere as rapidly as Covid-19.
Tania K: Hi. If a person is tested positive for Covid and had been socialising 3 days prior, (no masks, indoors etc) would the others that they were socialising with be deemed close contacts? If no, as a guide, how do you determine the timeline that would make you would become a close contact? Thank you.
RJ: Under phase 3 only household contacts are considered close contacts. Of course, if you have been socialising with someone with Covid and you have symptoms you should get a test.
Annette C: Hi Rod. With Omicron so infectious within households is it even realistic to try isolate infected household members as it seems likely the infection would have already spread within the home before you even realise. And for families with kids it's simply not realistic.
RJ: Good point. However anything you can do to slow it down will help. I remember getting a bad flu, but keeping away from my wife and kids as long as possible. When they got it, I was much better and was able to look after them.
Richard F: Hello. Current hospitalisation info shows a pretty worrying high proportion of admissions as 2nd vaccination/boosted people - far more than unvaccinated. Hopefully this is explained simply by there being far more of these people in the population, while relative risk remains far higher for unvaccinated people. Is this correct? Second question - is there still a case for the MIQ system now that community infection is now so much higher? Thanks.
RJ: Your answer to your first question is correct. With respect to your second (MIQ) question, my understanding is that it will be relaxed soon for the reason you give.
John A: Is there any justifiable reason why New Zealand citizens who are double vaxxed and show a negative test cannot entry this country? We had 3,330 community cases yesterday but the Government doesn't want to chance 1 more from offshore? MIQ just doesn't make any sense anymore.
RJ: Yes, see my answers [above] about the additional benefits of being triple vaxxed. Our main goal is to slow the spread of Omicron and triple vaccination is the most effective way of achieving this. Even if someone enters New Zealand double vaxxed and with a negative test, they are much more likely to get infected and spread it when exposed than a triple vaxxed person.
Simon F: Rod, I have made a graph of four of the Oz States' Omicron "waves", through to the present. I've scaled them to NZ pop 5 million. NSW and VIC have had big peaks and high total infections. QLD is middling. South Aust. is low and smaller. We hope to emulate SA possibly? Did SA have superior booster nos? Did they have harder rules? Will they have to catch up on total infections? Would they have been smarter to ease restrictions earlier? Once we are safely past our peak and hospitals are doing OK, what should we do with our rules?
RJ: Good question. I think comparing the Australian states' experiences is very worthwhile and yes, I hope we emulate South Australia. My understanding is that SA had more restrictions and they kept them longer than NSW and Victoria. I don't know about their vaccination rates and when they were vaccinated. However their experience with Omicron suggests more recent vaccination which would have meant they were at peak immunity when it arrived. I think our more recent vaccination peak gave us better immunity and is one of the reasons our Omicron outbreak has taken longer to take off.
Matt B: There seems to be a growing number of articles/statements on booster effectiveness with regard to Omicron, including from Pfizer, the WHO and early studies from countries' actual data. What do you understand to be the next step and timing for those who have now had their booster?
RJ: There is increasing evidence that a three dose vaccine course is the most effective for Covid-19. Most people probably won't need a fourth dose for some time. Also there is a huge amount of international activity around developing new and better, more long lasting vaccines. I think we could see some great new vaccines in the next few years.
Jacqui B: (From my 11yr old). Can Covid be passed on through blood? If someone with Covid cuts themself could that blood infect another person helping them or is it just with breathing and saliva?
RJ: No, it is extremely unlikely that Covid could be passed through the blood. It is transmitted from mouth to mouth ... [and] nose to nose.
Janet H: Is there a danger that efforts to protect ourselves now run the risk of simply putting off infection until protection from our boosters (we got ours just before Christmas) has run down? We have heard suggestions that protection from them starts waning at 2 months and is significantly eroded by 4 months.
RJ: As I have replied [above], three doses of the vaccine appear to give long (so far) - lasting protection against severe disease. The more immediate worry is that we haven't been exposed to flu for several years. International travellers usually bring flu into the country. We are going to need to put a huge effort into getting people vaccinated against flu this year.
Richard M: Why is the NZ academic community publishing so little useful information about long Covid when there has been clear evidence for at least 18 months that this is a very serious health issue?
RJ: Fortunately for New Zealanders, we have had so little Covid-19 so far that we don't have sufficient data to undertake robust studies on long Covid. However, I am glad you raised long Covid, which is increasingly acknowledged worldwide as a major issue.
Andrew B: Hi Professor Jackson. Much appreciate you doing this. Do you believe balanced against the harm they cause there is now any benefit in vaccine mandates or passes, especially given it was not extended to include boosters like in some other countries? My son didn't get the booster so was sick for two days unlike his friends in Dunedin who had got the booster. Tested and recovered now should he still get the booster and how is having omicron to be registered on vaccine passes / MOH record. Thanks
RJ: I think vaccine mandates should be extended to include boosters. As I have mentioned, the evidence is increasingly clear that this should be a 3 dose vaccine and we need to be prepared for future variants. And yes, I think your son should get a booster now he has recovered. Vaccination appears to give better more long lasting immunity than infection.
Suvi V: Should we be concerned about the new subtype H78Y of Omicron BA.2 that is spreading in Denmark? It seems to be more aggressive than previous subtypes.
RJ: Yes, we should be concerned and all eligible people should get boosted.
Em R: Good morning Professor Jackson. As a former student of yours I have very much appreciated your commentary on the pandemic and the response to the pandemic. My question is why with so many cases arising around the University halls of residence has the advisory committee not released recommendations allowing boosters for students who might not yet be 18? I understood that the technical advisory committee was due to release in mid February. Any suggestions? Alternatively perhaps you could lobby for this with a degree of urgency for us. Many thanks.
RJ: I agree that it is timely to consider boosters in 12-18 year olds. I am sure there is a lot of discussion going on, however NZ has always been more cautious than most countries with the introduction of Covid vaccines. In another post [above], this was raised as it is now recommended in the US.
John AL: With Omicron moving rapidly through Auckland now - and the fact that 90% of incoming overseas visitors come through Auckland - what will the difference in hospitalisations be, if we open up our borders(with no vax requirements) on Mar 1st to the whole world versus delaying it for say another 6 months?
RJ: It depends who the overseas visitors are as to the impact on hospitals. However it makes absolutely no sense letting unvaccinated people into NZ, given their much greater risk of severe disease and their higher risk of getting infected and then infecting others. As they are also moving all over the country they will spread it more rapidly.
Janet H: Does the current collapse of testing, tracing and genetic sequencing run the risk of the Delta outbreak flaring up on a serious scale? It's still around, and presumably on an unknown scale.
RJ: This is possible although worldwide Omicron has largely taken over from Delta, so it is probably a small risk. Nevertheless, we should be doing regular sequencing to check for this.
Tony B: If people are wearing KN95 masks rather than medical blue grade masks it has been reported that you get 25 hours protection versus 1 hour. Can you confirm this? Why [aren't] KN95 masks being promoted as the first line of defence for the public? Like RAT kits, KN95 masks are not easily accessible for the general public but KN95 masks can be ordered from Amazon & a few other websites. At $3 per KN95 mask isn't this something the Government should be promoting / subsidising to slow the spread of Omicron?
RJ: Good points Tony. I would like to see subsidised N95 and equivalent masks available to everyone and widely promoted. They are now much more widely available than even a few weeks ago.
Abbie N: I'm concerned about my 10-year-old daughter being only partially vaccinated with Omicron spreading quickly and her not due for her second vaccination until 23rd March. I had considered keeping her home once cases really increased just until she was fully vaccinated due to the (albeit very low) chance of severe illness and also the risk of long Covid which I would consider I should protect her from until her immune system has the same tools to fight Covid that the rest of us have as we are all fully vaccinated and boosted. Professor Jackson, if this was your child, what would you do?
RJ: Younger kids get significant protection from severe disease with even one dose, so I don't think you need to worry overly. Obviously two is better, but I would let her go to school. I have a granddaughter about the same age in exactly the same situation (one dose) and she is going to school.
Richard M: Do you think that the scientific community has been sufficiently vocally critical of the many obvious shortcomings in the Ardern Government's response to Covid-19 ? For example, we have paid a very heavy price for the failure to construct high-quality, large-scale, fit-for-purpose MIQ facilities that are by design able to keep a highly contagious airborne pathogen out of the community. The most recent MIQ failures have sent New Zealand on a path to endemic Covid-19 and exposed us to the risks of long Covid.
RJ: We have had the lowest infection rates, lowest hospitalisations and lowest death rates in the OECD. Also the Oxford stringency index on level of restrictions puts us in the middle of the pack. I think the scientific community largely believes we have done pretty well. Of course we could have done better, but I guess we haven't been overly critical because generally the Government has followed scientific advice.
Nick W: Given the high transmission rate of Omicron and that a number of double vaccinated/boosted will only get very slight symptoms or none at all, wouldn't they be more of a threat at spreading it publicly than the unvaccinated? If this was the case which it would appear to be with Omicron and with the eligible population 95% vaxed why are these vaccine mandates still being pushed so hard when the statistics to date haven't suggested a significant difference per 100,000 percentage wise, whilst also noting the group is denoting unvaccinated/unable to be vaccinated in one group fogging the transparency.
RJ: Unvaccinated New Zealanders had ten times the risk of hospitalisations as vaccinated New Zealanders in January this year and our biggest concern is the pressure on hospitals. Unvaccinated people are also much more likely to get infected when exposed to someone with Covid than vaccinated people (particularly compared to triple dosed people), so unvaccinated people are much more likely to spread it more rapidly. Also, many people (vaccinated or not) are infectious for several days before they get symptoms. So all in all, we need to get even more people vaccinated and boosted.
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