[ad_1]
To understand the spread of Covid-19, the pandemic is most usefully viewed as a series of distinct local epidemics. The way the virus has spread in different countries, and even in particular states or regions within them, has been quite varied.
A New Zealand study has mapped the coronavirus epidemic curve for 25 countries and modeled how the spread of the virus has changed in response to various blocking measures.
The research, which has not yet been peer-reviewed, ranks each country’s public health response using New Zealand’s four-tier alert system. Levels 1 and 2 represent relatively relaxed controls, while levels 3 and 4 are stricter.
FAKE IMAGES
Prime Minister Jacinda Ardern and Dr. Ashley Bloomfield at one of the Government’s regular coronavirus briefings.
By mapping the change in effective number of reproduction (Ref, an indicator of the actual spread of the virus in the community) against response measures, research shows that countries that implemented level 3 and 4 restrictions earlier were more successful in driving Ref below 1.
A Ref less than 1 means that each infected person spreads the virus to less than another person, on average. Holding Ref Below 1, the number of new infections will decrease and the virus will eventually disappear from the community.
Conversely, the higher the Ref Value, the more freely the virus is spreading in the community, and therefore the faster the number of new cases will increase. This means a higher number of cases at the peak of the epidemic, a higher risk of the health system being overwhelmed and, ultimately, more deaths.
Here are some of the findings from the study of states and nations around the world:
New South Wales, Australia
The effect of Australia’s stringent border control measures, implemented relatively early in the pandemic, can be clearly seen in the graph below. Federal and state governments introduced strict rules of social distancing; schools, pubs, churches, community centers, entertainment venues and even some beaches were closed.
This caused the Ref value to fall below 1, where it has remained for some time. Australia is rightly viewed as a success story in controlling the spread of COVID-19, and all states and territories are now charting their paths to relaxing restrictions in the coming weeks.
Read more: 90% jobless with a week notice. These 8 charts show the impacts of the coronavirus on unemployment in Australia
Italy
Italy was relatively slow to respond to the epidemic and experienced high Ref for many weeks this led to an explosion of cases that overwhelmed the health system, particularly in the north of the country. This was followed by some of the strictest public health control measures in Europe, which has finally seen the Ref drop below 1.
Unfortunately, the lapse of time has cost many lives. Italy’s death toll of over 27,000 serves as a warning of what can happen if the virus is allowed to spread uncontrollably, even if strict measures are taken later.
United Kingdom
The UK’s initial response to COVID-19 was characterized by a series of missteps. The government prevailed as it considered pursuing a controversial “collective immunity” strategy, before finally ordering an Italy-style shutdown to regain control over transmission of the virus.
As in Italy, the result was an initial increase in the number of cases, a late and successful effort to lead Ref below 1, and a large number of deaths of more than 20,000 to date.
New York, USA
New York City, with its field hospital in Central Park resembling a scene from a disaster movie, is yet another testament to the power of the spread of uncontrolled viruses to overwhelm the healthcare system.
Your Ref it reached a staggeringly high value of 8, before the city hit the brakes and completely crashed. It took a long battle to finally bring the Ref Below 1. Perhaps more than any other city, New York will feel the economic impact of this epidemic in the coming years.
Sweden
Sweden has taken a remarkably relaxed approach in its public health response. Except for a few minor restrictions, the country remains more or less open as usual, and the focus has been on people taking personal responsibility for controlling the virus through social distancing.
This is understandably controversial, and the number of cases and deaths in Sweden is much higher than in neighboring countries. But Ref indicates that the curve is flattening.
Singapore
Singapore is a lesson in why you can’t relax when it comes to coronaviruses. It was hailed as an initial success story to bring the virus to the heel, through extensive testing, effective contact tracking, and strict quarantine, without the need for a complete block.
But the virus has recovered. Infection groups originating among migrant workers have caused tighter restrictions. The Ref He currently has around 2, and Singapore still has a lot of work to do to take him down.
Individually, these charts each tell their own story. Together, they have a clear message: The places that quickly moved to implement stringent interventions put the coronavirus under control much more effectively, with fewer deaths and illnesses.
And our final example, Singapore, adds an important coda: the situation can change rapidly and there is no room for complacency.
Hassan Vally is Associate Professor at La Trobe University
This article is republished from The Conversation under a Creative Commons license. Read the original article.
