. To this day, Zaner has never knowingly had Covid, he says.
He is what scientists are calling a Novid, a super dodger, a Covid virgin.
Despite the ninth wave of Covid currently pushing up hospitalisations and deaths , some people have never had Covid or – more likely – had it with no symptoms, so never tested to know. It’s an exclusive club that scientists are studying with the goal of eventually reverse-engineering better immunity for similar illnesses and future pandemics through better vaccines and other measures.
Theo Gerritsen, an 87-year-old who lives in Hamilton, puts his Novid status down to a salad bowl of ingredients: genetics, a healthy lifestyle, getting the vaccine and following Covid guidelines from the government . He can’t remember the last time he had a cold or the flu.
“Put it this way, I visit a doctor, maybe, well, I wouldn’t even see a doctor once a year.”
I, too, have been left to ponder why I have dodged Covid for six years. And I pushed the envelope, travelling from Level Three Lockdown Auckland to restriction-free Florida at the end of 2021. Any protection from my two vaccine shots felt entirely offset by two grubby kids. The American grandparents we were visiting were indifferent to taking virus precautions, so I quickly gave up and embraced Florida’s relaxed Covid restrictions.
I’m still waiting for a call from science asking to study my apparently phenomenal immune system and that of my dad, two kids and husband. We are all Novids – as far as we know.
Studies have been done and are underway to discover the mystery of Novids, according to Associate Professor Helen Petousis-Harris, a vaccinologist from the University of Auckland. A key area of interest for scientists is genetics in those who have been exposed to the virus again and again without getting sick, she says.
Auckland University vaccinologist Helen Petousis-Harris.
RNZ / Dan Cook
“We’re now seeing some gene variants that are associated with this gift, if you like.”
Scientists are circling in on a particular gene variant, and if people have two copies of that variant, then they are eight times more likely to avoid Covid symptoms than those without a double, says Petousis-Harris.
Those particular molecules have shown an increased effectiveness in taking a seasonal coronavirus and putting up a quick defence against viruses with a similar makeup, she says.
Diversity of genes, like having parents from different regions of the world, can also boost your immune response in general.
“…we also know at the other extreme end, when you get a lot of, you know, very small communities inbreeding, I think the people tend to not be as strong as those who live in normal, larger communities and aren’t as closely related to each other.”
Scientists are also looking at the noses of Novids and their basal immune tone, “so basically the level of immune activation you have in your nasal passage,” says Dr Kerry Hilligan, a cellular immunologist at the Malaghan Institute of Medical Research in Wellington.
Dr Kerry Hilligan, a cellular immunologist at the Malaghan Institute of Medical Research.
ROBERT CROSS
While laypeople think of immunity in terms of white blood cells, regions of the body also have a specific immune response. This includes cells that line the nasal passages, says Hilligan.
“What [scientist] found is particular people that have the sort of higher level of activation, that the Covid virus really doesn’t like that and it really struggles to infect in those conditions.”
The cells interfere with the virus, preventing it from getting in and from multiplying.
“That’s one of the reasons why we think children are actually protected because if you look at the immune tone of the nasal passages of children, they are generally very high, partly because of their age and then partly because everything goes on the face and the mouth, up the nose, and so the immune response is heightened.”
Hilligan is quick to point out that exposure to germs could strengthen your immune system against Covid, but that same tactic doesn’t work so well when it comes to RSV, or respiratory syncytial virus. Children are more susceptible to RSV, she says.
“While these traits might be really beneficial for Covid, they are probably not beneficial for other things.”
Booster vaccines are one of the best forms of protections available to the public, Petousis-Harris says.
While a booster vaccine will not stop a person getting infected by Covid-19, it will reduce the risk of getting seriously ill from the virus.
“The latest vaccine is well-matched to the variants driving this wave. It won’t stop you getting infected, but it significantly cuts your risk of ending up seriously ill.”
She says anyone over 30 is eligible for free booster vaccines. Ideally, these should be taken every six months.
“That protection is real, but it fades, so staying up-to-date matters.”
Apart from staying up to date with boosters, University of Otago professor of public health Michael Baker says self-isolation is important in reducing the spread of Covid-19.
He says anyone who has respiratory symptoms should stay home, whether they have been tested or not.
