Here’s how SA’s vaccine algorithm works – and location is more important than age

Business Insider SA
CAPE TOWN, SOUTH AFRICA - MARCH 05: A general view
(Ziyaad Douglas/Gallo Images via Getty Images)
  • South Africa's EVDS system decides who gets vaccinated when and where – although walk-ins are being served.
  • Other than healthcare workers, only people older than 60 can currently get vaccine slots.
  • But age does not determine priority, it is just a precondition for getting in the queue.
  • Your proximity to a vaccination centre is more important than how old you are in the algorithm that determines when you get an SMS invitation.
  • Then the date and time you registered comes into play – and whether you are a member of a medical aid.
  • There is no prospect of being able to select a date and vaccine location convenient for you, ever.
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South Africa's vaccine algorithm, the part of the sprawling Electronic Vaccination Data System (EVDS) that determines who gets a vaccine shot when, does not prioritise recipients by age.

In order to be in the queue for a Covid-19 vaccine at all, you currently have to be either a healthcare worker, or at least 60 years old. But if you fall in that general population group, it make no difference if you are 60 and one day old, or have lived for 99 years. Nor does it matter if you have co-morbidities which make you statistically more likely to have a dangerous case of Covid-19 if you get the coronavirus.

See also | It’s official: No vaccine priority for South Africans with co-morbidities – ever 

But where you live could make all the difference.

Here is how the algorithm allocating South Africa's Covid-19 vaccine shots works.

Once you are 60 years old, you're in – and then age no longer matters.

Giving vaccines to people over the age of 60 means exactly that, says Nicholas Crisp, the department of health deputy director general in charge of the system. Being 60 is a pre-condition to getting in the queue for the vaccines currently available. Once you are in the queue, though, age is no longer a factor; there is no priority for those who are older.

Nor is your general state of health, and so statistical likelihood of severe Covid-19, involved. 

"You are just in the cohort because you are at least 60," says Crisp.

Your address will determine if you get an invitation.

When a vaccine centre enters service, those who registered addresses within its catchment area are scheduled for vaccinations.

In urban areas, that is for people within 10km of the vaccine site. In rural areas people who are within 30km of the site get on the schedule.

Several hundred vaccine sites are already active – though the official list is very outdated – and more are due to be activated almost daily, until a total of some 3,300 are reached.

The catchment areas for centres may be adjusted as necessary, Crisp says, "we may push that down to 5km in urban areas, or go beyond 30km in rural", which means people in cities further back in the queue may have more convenient trips, and those in far-flung areas may see invitations come in even if new vaccine centres do not come to their towns and villages.

For those within reach of a vaccine site, only when they registered matters.

No other factors matter for those who are in the eligible group, and fall within reach of a vaccine site, Crisp says. Once those conditions are met, it is first-come first-served: those who registered on the EVDS first will be sent their invitations first. 

Some of those registered say that is not the case, but Crisp says such anecdotes have simple explanations. 

"Where you have a husband and wife who are not on the same day, what has happened is that they registered together, but a lot of other people may have been registering at the same time, so you may have 30 or 40 other people who submitted between the time the husband registered and the wife registered."

In other instances, incomplete addresses could come into play. Wrong post codes, different suburbs with the same street name, and similar geo-location trouble have all seen people placed into the wrong catchment area, says Crisp. Those issues are being addressed.

Whether or not you are a member of a medical scheme matters – maybe.

As a rule, "private" vaccine recipients – those who have medical aid – are sent to private vaccine sites, while those without health insurance are sent to public health facilities.

But it all depends on capacity, and the queue, at each facility, says Crisp.

"[The system] will look at medical aid members going to private sites, but will then top up with people who don't have medical aid, and it will do the same for public sites; uninsured first, and if there is an insufficient number of those, it will top up with the insured."

You'll almost certainly never get to select your site or slot – formally.

Despite early talk of a full booking system, where recipients would be able to select a slot and venue convenient to them, that is just not going to happen, says Crisp. That would make allocation of resources too complicated.

But that does not mean arrangements can not be made.

People who "don't have time to site around" can, in theory, "say to a site I have a code, I am registered, here is my ID and proof of registration, please schedule me, private sites are able to do that."

Some sites currently accept walk-in recipients on a roughly similar basis, with official tolerance for the practice. But how sites deal with scheduling is up to them, says Crisp, it is their operating hours, and the extent to which they prioritise healthcare workers.

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