For more than a year, the concept of herd immunity against COVID-19 has fuelled political and economic debate across the world. The idea: when a sufficient number of people achieve medically induced or natural immunity, we can all go about our business and even open up the borders.
Here’s a definition: herd immunity occurs when a large portion of a community (the herd) becomes immune to a disease, making the spread of disease from person to person unlikely. As a result, the whole community becomes protected — not just those who are immune.
But we now have an Australian contribution to the debate thanks to the newish boss of Virgin, Jayne Hrdlicka, the most senior business figure to make the case that borders need to open even if “some people may die”.
So what might “Hrdlicka immunity” look like? Crikey asked economist Richard Holden to turn his mind to it.
Here’s what he came up with: “Hrdlicka immunity is defined as: Virgin Australia segments flow * (1-mRNA vaccination rate) * R0<1.”
To spell out the idea in more detail:
- Virgin Australia segments flow is the average number of Virgin flights per person
- (1-mRNA vaccination rate) is the proportion of the population susceptible to infection since that proportion haven’t had Pfizer or Moderna vaccine. That assumes Pfizer/Moderna are 100% effective, which is close enough, and assumes AstraZeneca doesn’t help — which is not right but works as an implicit simplification
- R0 is the basic reproduction number of the virus. We need that product to be less than 1 to achieve herd immunity.
Of course, as Holden notes, the gloss here is we are assuming that only people flying on Virgin might infect others or be infected with COVID-19. Which is obviously cute, if not a tad contrived.
See how power works in this country.
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As I understand it, R0 is the net reproduction number of the virus, representing the sum total of all the processes that pass infection from one person to others. It is one if at the end of each patient’s infectious period, there is on average only one new infectious person replacing them in the statistics.
Given Peter has been the editor approving the publication of Dr. Adam Schwab M.D.’s expert medical opinions in his COVID articles for the last 18 months… it’s no surprise he has reached for an economist as an expert regarding herd immunity.
Love “herd” immunity not population immunity. You know like cattle not people.
Same same Human”Resources”Manager, not the same as Personnel Manager.
You are not a human unless you’re rich or “important”.
Unfortunately we have a duopoly in the airline market, or perhaps a one-and-a-halfopoly. If I want to visit family in the Indian Ocean Territories I have to use the monopoly Virgin flights. Otherwise I’d put Virgin on my “do not use” list. But that only leaves the lovely and talented Qantas, not a happy choice. Hurry up Rex, start your Perth flights.
Let’s ask Dick Holden – an economist, who seems to swing from open up to shut down, and then sometimes gives his balls splinters by sitting on the fence