Explainer: Can we still avoid Covid-19 and is there any point trying?

With new Covid-19 case numbers down, many may be asking if there's any point keeping up precautions to avoid the virus, particularly those who haven't caught it yet.

Is it still possible to protect ourselves from the illness? Surely we're all going to get it at some stage, and the 'milder' Omicron variants make it less of a threat to our health, so what's the big deal? Here's what you need to know.

We are now more than two years into a pandemic that turned many people's lives upside-down.

Despite a creeping complacency, a relatively relaxed approach to Covid-19 in schools, and reports of people catching the virus twice, there are still a lot of New Zealanders who have never tested positive.

How many Kiwis have never caught Covid-19?

That can only be an estimate, because some people may have had the virus but weren't tested at the time, for example if they were asymptomatic.

Rapid antigen tests (RATs) are now being used regularly and Ministry of Health daily case numbers rely partly on people reporting their own results, something that's not always happening.

Wednesday's Ministry of Health update reported 2825 PCR tests carried out in the previous 24 hours, compared with 13,413 rapid antigen tests. The PCR tests rolling average in the last 7 days stood at 2661, compared with 1.3 million for rapid antigen tests.

As of Wednesday, there were 1,213,546 confirmed or probable Covid-19 cases recorded in New Zealand throughout the entire pandemic.

When you compare it to New Zealand's estimated population of about 5,127,100, it's clear there would be a significant number of people who have not had the virus.

If it's likely I'll get Covid-19, why bother protecting myself?

There is an element of fatalism now in some quarters regarding Covid-19, with the view that contracting the disease is a certainty. But there remain compelling reasons to continue to dodge the virus, using tried and tested means of doing so.

Infection brings risk of significant health complications and death, particularly among those with pre-existing conditions and the elderly.

A risk to everyone in society is the post-viral disease known as Long Covid. All variants can bring on the condition.

By some estimates about 15 percent of people who contract the virus will get Long Covid. Diagnosis is reached if symptoms last more than three months. Symptoms may change over time and new symptoms may develop.

It can involve long-lasting and debilitating fatigue, neuro-inflammation, blood clots, and a multitude of other severe symptoms. There is no cure and the nature of the disease, which is similar to myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS), is poorly understood.

"About one in 1000 people who get this infection are dying from it," says epidemiologist Michael Baker, Professor of Public Health at the University of Otago.

"So it's still best avoided and I guess the biggest concern is Long Covid. That's what I'm concerned about and why I'm concerned about my children being infected."

Can we avoid it?

The Omicron case numbers peak has subsided. However, the possibility of further waves of the virus remain.

Although we're in a different phase of the pandemic, with the advent of effective vaccines and a high uptake of Pfizer shots, Baker says the ways we can protect ourselves have not changed.

"There remain three big pillars of our defences, which is vaccination, and cases isolating themselves so they don't infect those around them, and thirdly, reducing transmission around people - so that's about places you're in, wearing your mask and that type of thing.

"Some of them relate to you personally and some relate to the people you're around."

Wearing the best mask

An N94/5 mask remains the most effective mask to wear to avoid infection, above surgical masks.

Baker says these are the go-to masks for something as transmissible via airborne particles as the Omicron variant.

"They're very different from the surgical masks that people wear," he says. These are the ones that have a pretty good fit on your face and good filtration ability. It's also important to have other people around you wearing masks if you're indoors."

Homemade cloth masks remain the least preferred.

Places and protection

Covid-19 is widespread and there are places we can't easily avoid, like the workplace or schools. It is important to be conscious of the situations you're in and the conventions that apply there, Baker says.

"If you're in an open-plan workplace you'd hope you're employer is reinforcing a policy that those showing any symptoms at all are required to stay at away."

Where you are having meetings without a mask, that area needs to be well-ventilated and social distancing maintained.

It is highly likely you will pick the virus up from someone you live with.

But this too can be avoided. Most people know of cases where people have avoided sharing their spouse's or children's infection. Catching the virus in this situation is not an inevitability. It has been Baker's own personal experience.

"No one wants to wear a mask around the house, unless you've got a case," Baker says.

"My eldest daughter got sick a week ago and she's doing okay, but it means of course we isolate her in one corner of the house and we wear masks around the house and so far we've avoided it. But you don't want to wear a mask continually in your home if you haven't got an infected person there."

Dodging the virus in the home is still determined by a degree of collective responsibility shown outside of it.

'I think the basic precautions are anyone who is going out of the house, you have two main settings - where adults go to work and children go to school or university, and then there's special things," Baker says.

"So if everyone is taking precautions in those settings it minimises the chances of it coming home."

Ensure safety in schools

Due the high rates of transmission, Baker has a big concern about what he sees as the relaxed approach taken regarding schools. "I think it's premised on the view that this is a mild infection and I just don't think the evidence supports that view," he says.

But parents can be proactive and push schools to insist on enforcing a mask-wearing policy, for example.

"One thing you can do is talk to the people at your schools and say can you please have a mask policy all the time to avoid transmission," he says.

Social events don't need to be transmission events

At events such as weddings and birthday parties there can be a risk of high transmission, despite best efforts, with guests taking off masks to eat or drink for example. But there are still ways to lower the risk.

"A lot of people do have the option of having social events outside under cover. Obviously going through winter you do want to have cover for these things, with good ventilation," Baker says.

"That is the compromise you can have with events, keeping them a modest size and having them outdoors under cover."

Good ventilation can be as simple as opening windows and doors, or using an air conditioning system that brings in outdoor air.

Avoid repeat infections - get your boosters

There is a chance of getting repeated Covid-19 infections with the variants circulating in the community, including the Delta, Omicron and the Alpha virus.

"The virus is everywhere in New Zealand now," Baker says.

"We've settled down into a state where we're getting about 7000 cases per day, probably twice that number in reality. So it's still a common infection. We're past the peak but there's still a lot of people getting sick every day and still about 400 people in hospital at any one time."

Vaccination remains key to avoiding sickness, he says.

"It's a concern that a third of adults haven't had their booster and it's a concern that only 25 percent of children aged between 5-11 are fully vaccinated or have two doses. Those are the two big holes in our vaccination coverage. It definitely decreases your risk," Baker says.