By Siouxsie Wiles 14/03/2020


Spinoff cartoonist Toby Morris and I recently introduced you to the concept of #FlattenTheCurve. Now we want to get you thinking about a more ambitious idea: #StopTheSpread.

But first, a quick recap. During an outbreak, if we can’t control the spread of the disease, then the number of sick people quickly rises. For Covid-19 we know this: about two out of every 10 people will need to be hospitalised for between two and six weeks. About one in 20 people will end up in intensive care, and one in a hundred will need a ventilator to help them breathe.

But we only have so many hospital and intensive care beds and ventilators. And they aren’t just sitting around waiting for an outbreak. Lots of them are already being used to care for people with things other than Covid-19. In New Zealand, we are just about to head into winter, the busiest season of the year for hospitals. If Covid-19 took hold here, our medical staff could find themselves in the awful position of having to decide who gets a bed or a ventilator. If you don’t think this could happen read this report about Italy.

That’s where #FlattenTheCurve comes in. It means pulling out all the stops to try to slow the spread of the disease. If we can spread the number of people who contract the disease over a longer period of time, then we’ll have enough beds and ventilators for everyone who needs them.

Here’s how we expressed that earlier in the week:

The graphic is based on an article by Prof Sir Roy Anderson and his colleagues that was recently published in the Lancet. Sir Anderson is a professor of infectious disease epidemiology at Imperial College London and chief scientist at the UK’s Ministry of Defence.

We have now augmented it further, but before we get to that I want to explain why.

One of the things the latest studies are showing is that some people may be able to shed the Covid-19 virus for up to three days before they have symptoms. This is obviously a worrying development as it does mean that people may be more infectious in the early stages of Covid-19 than we initially thought. But it’s also important to mention that many of the people in these studies were living in the same household. That fits with all the data showing that most people need to be in repeated close contact with someone who has the virus to pick it up.

Right now we need every household to sign up to the FluTracking project which is helping to act as an early warning system for Covid-19. We need everyone to get into the habit of washing their hands properly and regularly, and to avoid touching their mouth, nose, and eyes. It’s really hard, I know! Out, too, are hugs, kisses, and hongi.

We need to stay away from other people if we are sick. That means, if we are at all unwell, no going to church, the gym, the theatre, cinema, or to gigs and festivals.

Most importantly, we need to be calling ahead if we feel ill and want to go to the doctor or hospital. Something that will not #FlattenTheCurve is having a whole bunch of healthcare workers in isolation because they’ve been exposed to Covid-19. In fact, that does the opposite: it reduces our capacity to care for people who are sick.

If all these measures aren’t able to slow things down enough, then we’ll need to take more drastic action. That could be anything from as many people as possible working from home, and stopping all large gatherings, to a full-on lockdown like China and Italy have had to resort to.

#StopTheSpread

At the time of writing, all the cases of Covid-19 we’ve had here in Aotearoa New Zealand are related to travel overseas. We don’t think we have transmission of the virus happening in our communities. But if it is, we are at the very early stage of the outbreak and that means we have an option other than to #FlattenTheCurve. And that is to #StopTheSpread.

Taiwan, Singapore, and South Korea are examples of #StopTheSpread. They’ve all used slightly different strategies which we can learn from. But they acted quickly, with no half measures. We need to be prepared to do the same at the first sign of community transmission. That may be in the next few days, or it might not happen for a few weeks. So, this weekend, touch base with your whānau and friends and get your pandemic preparedness plan together.

The important thing for any country that is able to #StopTheSpread is to not become complacent or if stop doing what needs to be done “perhaps to mitigate economic impact” as Sir Anderson and colleagues put it. Until a vaccine is ready, and that could take one to two years, we are all susceptible to this virus. If we turn our back for a minute, we’ll be back on the path to a serious outbreak.

As more and more countries see community transmission, to keep the virus out New Zealand will need travel restrictions on a scale we’ve never experienced before. Whether these are outright bans or 14 days in isolation is a decision for the government to make.

I’ve said it before, and I’ll say it again. Prepare, don’t panic. Look after the vulnerable people in your community. We’re all in this together. And we are in it for the long haul.

This post was originally published on The Spinoff. The Spinoff’s ongoing COVID-19 coverage is being supported by the Spinoff members.


0 Responses to “After ‘Flatten the Curve’, we must now ‘Stop the Spread’. Here’s what that means”

  • I have questions:

    Irrespective of whether the curve is flattened or not will the same number or proportion of people in a population catch Corvid-19 by the end of the epidemic?

    The answer is not clear to me but if a long epidemic means it will take longer to reach some level of herd immunity then more people may end up catch the virus than in a short epidemic with rapid attainment of safer levels of herd immunity, and the only advantage is more victims might receive better treatment (or we find a cure or vaccine). Do we have any data of the proportion of at-risk patients with the virus that survive against the level and sophistication of the treatment they received?

    Populations (countries) that do flatten the curve and limit spread are held up as the templates and in the short-term they are less risky for us than those where the disease is rampant – and thus the total ban on some but partial measures (isolation) for people from others. But who is the greater long-term risk to New Zealand, those who have not reached herd immunity levels or those that have?

    As an older person seeking the best individual risk reduction strategy (cf the best population risk strategy that governments must follow) it might be better and easier to isolate during a short epidemic than trying to isolate over a long time, i.e. to allow a high level of herd immunity and (I assume viral demise) before I emerge??

    I suspect a short epidemic would also be better for the economy. A few months and airlines might survive, a year and most will go bankrupt.

    So, the pictures of prevalence over time seem to be data-free and not much use to either me and my decisions around personal behaviour, nor actually to epidemiologists advising government on what to do.

    John Parkes

  • PS

    More questions than answers:

    So what is the end-point we desire?

    1. The disease disappears as herd immunity levels are reached?
    2. What are these population levels – % immunes and probably density dependent transmission rates?
    3. Do antibodies confer permanent immunity?

    4. What are the prevalences of susceptibles, infected, immunes by age class across the epidemic? No use just testing suspected cases. I assume someone is looking at cross-sectional samples or even longitudinal testing?

    5. Will it be an endemic disease with seasonal outbreaks like other coronaviruses?
    6. If so will Covid-19 attenuate and over how long? Given its mode of transmission it should become less virulent.

    I am not sure how we can develop an optimal strategy or compare the current options without basic epidemiological data!

    JOhn