Don’t beat about the booster – get vaccinated!

It’s recommended that certain people get yet another booster shot of the vaccine, and questions abound as to why – or if – this is necessary. Let’s look at some facts:

Let’s start by stating that the COVID-19 pandemic isn’t over. True, we certainly aren’t experiencing the fearful anxiety of the early days of COVID-19. Worldwide data on the pandemic also does appear to indicate that it is, indeed, receding.

Nevertheless, on average, there are still more than 200 000 recognised cases and more than 2 000 reported deaths a day globally. Of course, the true figures are considerably higher as data is very sketchy, especially from China, which has been rather cagey about releasing its data.

South African data, which reports about 250 new cases per day, is even more deficient, as active surveillance has dropped markedly. Global public health has also focused on the post-COVID-19 syndrome, or long COVID, which is characterised by the persistence of symptoms, sometimes quite disabling, for anything from six months to a year after acute attack.

By far the dominant variant in the world today is still the Omicron variant. The XBB.1.5 subvariant (a recombinant of two earlier BA.2 subvariants) has spread rapidly in many countries of the world and has also been detected in South Africa. There was some concern about this subvariant because of its very high transmissibility (the highest of all COVID-19 viruses so far), as well as its ability to partially escape neutralising antibodies.

However, because the other arm of the immune system, the cellular arm, is more durable in preventing escape, immunity after infection or vaccination would still be reasonably good, particularly in preventing more serious infections. Fortunately, disease severity is considerably lower with all the Omicron subvariants.

So, what of the fifth dose?

There’s some confusion about what constitutes a primary and a booster vaccination. The first two doses of either the Pfizer (mRNA) or Johnson & Johnson (Ad26) are considered primary vaccination and any subsequent doses are booster doses. The current SMS campaign addresses the third booster, or fifth dose, for seniors 50 years and older. Age is universally the single most important determinant of serious disease. A recent study in the United States found that more than 80% of all COVID-19 mortality occurred in individuals over 60 years of age.

Of course, the first consideration is to ensure that all the recommended doses are up-to-date, and any deficiencies should be remedied as soon as possible. Briefly, all adults above 18 years of age should have received their primary dose and an additional two doses. Currently, adolescents 12 to 17 years of age aren’t scheduled for a booster dose after their primary. Children under 12 years of age aren’t recommended for COVID-19 vaccination unless they have underlying illnesses putting them into a high-risk category.

Is a fifth dose necessary?

Do we 50+ “oldsters” need a fifth dose? The answer depends on the current status of the COVID-19 pandemic and the status of our immunity. I have briefly outlined the status of the pandemic as we know it. Certainly, COVID-19 activity is at a low level in this country even though we don’t have a good handle on the statistics.

However, we’re unfortunately heading out of summer and into autumn, with less outdoor activity and usually an increase in respiratory-spread viruses, including COVID-19. Although COVID-19 doesn’t appear to be a seasonal infection, nevertheless respiratory-spread pathogens generally do spread more rapidly in the indoor environment of colder weather.

On the other hand, the great majority of South Africans (more than 95%) have been exposed to the virus and/or the vaccine, usually both. We all have at least some degree of residual immunity. The duration of this immunity is still being studied, but data indicate at least good protection from serious illness for up to nine months post-infection or post-vaccination. Nevertheless, studies have shown that the additional booster dose (the fifth dose) significantly improves immunity to infection and international bodies have therefore universally recommended it for older individuals.

Is the vaccine safe?

Yes, yes, yes. Regrettably, one of the downsides of a free press is that it enables mischievous individuals to spread false information, conspiracy theories, and fake news. One of the casualties has been vaccines, especially COVID-19 vaccines. Of course, nothing that is highly effective can be 100% safe, and side effects from the vaccine do occur.

Discomfort for a day or two after vaccination is fairly common, but the more serious side effects, which get the publicity, are extremely rare. They are of the order of a handful of cases per million doses, considerably less than the risk of misfortune when travelling to a seaside vacation, and, of course, far less than COVID-19 illness itself.

Is there an Omicron-specific vaccine?

There’s no stand-alone Omicron-specific vaccine. Vaccines in use are still made from the original strain which started it all in Wuhan, China, in late 2019. Soon after Omicron was detected, Pfizer developed what is called a bivalent vaccine, in other words, a vaccine with both the Wuhan strain and also an Omicron strain (the original BA.2 Omicron subvariant). The bivalent vaccine has been in widespread use in many northern hemisphere countries as a booster. Results, however, haven’t been much better than the original single-strain vaccine. The bivalent vaccine isn’t registered or available in South Africa, and only the original single-strain vaccines are used for primary and booster doses.

Where do you get vaccinated?

With the sharp drop-off of interest in vaccination in this country, most regular vaccination sites have closed down and many people are struggling to find a place to get vaccinated. My suggestion is to use the website “Find My Jab” – https://findmyjab.co.za – which will direct you to the nearest available site. I would also recommend calling the site beforehand to ensure they have vaccine in stock.

The bottom line is that my wife and I will be going for our fifth dose next week.

• Barry Schoub is professor emeritus of virology at the University of the Witwatersrand and was the founding director of the National Institute for Communicable Diseases. He chairs the Ministerial Advisory Committee on COVID-19 Vaccines. This article is written in his private capacity. He isn’t a member of the health department, and receives no remuneration for his advisory services to the department. He reports no conflicts of interest.