SA data shows vaccinated adults have a 94% lower risk of death from Covid-19

The Pfizer/BioNTech vaccine reduced the risk of being hospitalised or dying from Covid-19 in SA by more than 90%, according to a real-world study by SA medical scheme administrator Discovery Health.

It found people who had received both shots of the two-dose jab had a 92% lower risk of hospitalisation and 94% lower risk of death from Covid-19 than those who had not been vaccinated, up to three months after immunisation. Even a single shot offered significant protection, reducing the risk of hospitalisation by 73% and the risk of death by 79% after 14 days.

The local findings are consistent with a US study published in The Lancet in October, which found the effectiveness of two doses of the Pfizer vaccine against hospitalisation remained high even at six months, at 93%. The findings emphasise the importance for SA of rapidly scaling up coverage.

SA had by November 3 administered 22.8-million vaccine doses and fully immunised 31.7% of the adult population with either the two-dose Pfizer vaccine or the single-shot Johnson & Johnson jab.

The government had hoped to vaccinate 70% of adults by the end of the year, but Discovery Health’s projections estimate it will reach only 52%, said CEO Ryan Noach. "That is of course a concern for lives and livelihoods, because vaccination is the most important tool we have to return to normal life," he said.

The restrictions imposed by the government in response to the pandemic have battered the economy, shrinking GDP by more than 6% in 2020 and leading to the loss of more than 1-million jobs.

The SA study included more than 1.2-million adults who had received the Pfizer vaccine and covered the period from the start of the government’s vaccine rollout on May 17 to September 23.

The time frame is significant because it coincided with SA’s third surge in infections, dominated by the highly transmissible Delta variant, said Noach. "This must be one of the largest [real-world] studies [into] Delta and vaccine effectiveness," he said.

Discovery Health is a subsidiary of JSE-listed health and life insurer Discovery. It administers 19 medical schemes that cover 2.9-million lives.

The study found no waning in vaccine effectiveness at protecting recipients against Covid-19 hospital admission and death in the three months after they received the second dose. Given global concern over waning vaccine efficacy, Discovery Health would continue to monitor the data, Noach said.

UCT head of infectious diseases Marc Mendelson said Discovery’s findings are in line with global evidence to date.

"It is highly encouraging in terms of reduction of hospitalisation and death, but it is a short follow-up period. The key issue now is how protection wanes, and we expect it will do the same [in SA] as it has done elsewhere," he said.

Discovery Health’s analysis included 526,516 Covid-19 tests, 14,673 Covid-19 hospital admissions and 3,441 Covid-19 deaths. It found vaccinated men and women were at equal risk of hospital admission and death from Covid-19 and that vaccinated people with chronic conditions were no less protected than people without these underlying illnesses.

However, vaccinated people with three or more underlying conditions were at higher risk of hospitalisation and death from Covid-19, as were vaccinated people over the age of 80.
The study found vaccinated people who had recovered from coronavirus infection before getting their shots had a much stronger immune response than those who had never had
Covid-19. Their relative risk reduction in hospital admission for Covid-19 was 98%.

Discovery Health chief health analytics actuary Shirley Collie warned that prior infection is no guarantee of enduring immunity, as 11,500 Discovery Health members had tested positive for Covid-19 a second time and 37 members tested positive three times.

Discovery Health chief commercial officer Ron Whelan said unvaccinated members are at five times higher risk of
Covid-19 infection and 20 times higher risk of dying from
complications than people who are fully vaccinated with the Pfizer jab. "We have seen no [Pfizer] vaccine-related deaths. That should give some reassurance that the vaccines are safe."

kahnt@businesslive.co.za