New Covid sub-variants are circulating, and hospital admissions are up. Here’s how to lower your chances of going down during the ninth wave.

Last week, 50 people were hospitalised with Covid and 19 people with the virus died. 

University of Otago epidemiologist Michael Baker says those figures are a sign that a new wave of Covid – the ninth since the Omicron variant first spread in 2022 – is beginning in New Zealand. (Prior to 2022, the virus wasn’t circulating widely in New Zealand; after Omicron, the virus has followed a pattern of about two waves each year.)  

Are hospital admissions and deaths the only way we know what’s happening with Covid now?

There are  four sources of data about Covid infections. As well as hospitalisations and deaths with Covid, New Zealand tracks self-reported cases of the virus and does wastewater testing. 

These days, the numbers of self-reported cases are negligible, because very few people are still testing for the virus and even fewer are logging their results online. 

Wastewater testing doesn’t provide exact numbers, but gives useful information about which variants are circulating and approximately how many people are infected.

Is the ninth wave any different than previous waves? 

Yes, slightly, according to Baker: “The wastewater testing shows that there are multiple circulating subvariants, not one dominant variant that’s crowding out others”. He says that’s a sign that rising cases are due to waning immunity.

Am I more protected from Covid now it’s been around so long?

You can develop immunity in two ways: by getting sick with Covid, which means your body develops an immune response, but tamps down as time passes, or by getting a vaccine, which exposes you to a weakened version of the virus that can prepare your immune system for infection, without the disadvantages of actually getting sick.

Getting a vaccine provides immunity without the risks associated with a Covid infection, including long Covid, when ongoing symptoms like fatigue and breathlessness persist for months. “That will be the largest long-term consequence of the pandemic – tens of thousands of people with a disabling condition,” Baker says. “For some people that gets better over time […] but there are few if any effective treatments.”

The last Covid wave occurred about six months ago. That’s long enough that  people who gained immunity then from being sick may be able to get infected again. 

Covid remains a deadly infectious disease, associated with about 1000 deaths a year in New Zealand – compared to around 500 for influenza. 

Is the vaccine effective if there are new subvariants circulating? 

“The strains of the virus keep evolving, but the booster vaccine still gives good coverage,” Baker says. 

Getting a vaccine makes it less likely that you’ll fall ill, but it’s still possible. 

The value of the vaccine is that it protects against serious, life-threatening illnesses as a result of Covid, Baker says. 

“You can get dream vaccines like MMR, which provide lifetime protection against getting or transmitting measles, mumps and rubella,” Baker says. But for diseases like influenza and Covid “it’s a challenge for vaccine designers to make something which creates long-term immunity and prevents you from passing on the virus”. For now, these vaccines are most effective when people receive them regularly. 

While booster vaccines are freely available to anyone over age 30 (and to vulnerable groups), low uptake contributes to the virus spreading and people getting seriously sick. Baker would like to see access to booster vaccines extended to everyone over the age of 18, as is the case in Australia. “People in their twenties are teachers, healthcare workers – they’re coming into contact with a lot of potentially infected people,” he says. 

Honestly, we’d really rather not get Covid at all – even if the  vaccine stops us getting severely sick. Help! 

Self-isolate if you test positive for Covid (or any other transmissible respiratory illness). It is one of the best ways to stop the virus spreading. There are standard rapid antigen tests which detect Covid as well as more expensive combined tests which also can detect the flu and RSV. Unfortunately, few people are testing for Covid now, as indicated by the low numbers of self-reported cases. Baker believes that’s because the tests are no longer free.  

You can also reduce the viruses in the air you’re breathing by improving ventilation, Baker says. That means opening a window or door or talking to your employer about air ventilation and using filters or sterilisers. 

You can’t always control the air around you, like on public transport or planes. In those circumstances, Baker recommends a well-fitted respirator mask, like an N95. They provide a high degree of protection. While mask use was common in 2020 and 2021, New Zealand has reverted to not wearing masks. Baker hopes to see a swing back to mask use and believes if more people don a mask, their use quickly spreads. The more masks we see, the more likely we are to mask up. He suggests when you see a wave starting, get your mask out and wear it if you commute. 

He also encourages people to cancel events if they’re sick, and says the more people that do this, the more it becomes a social norm. Think about it: who wants to a friend sharing their virus?  “You don’t want people to just taking some pseudoephedrine, covering their symptoms and soldiering on.”