* Health workers were due to get AstraZeneca jabs soon
* Trial data show significantly reduced protection vs
variant
* Johnson & Johnson, Pfizer shots to be offered instead
* Scientists say vaccination strategy needs to change
(Adds quotes, data details, context throughout)
By Alexander Winning and Olivia Kumwenda-Mtambo
JOHANNESBURG, Feb 7 (Reuters) - South Africa will put on
hold use of AstraZeneca's COVID-19 shot in its
vaccination programme, after data showed it gave minimal
protection against mild-to-moderate infection caused by the
country's dominant coronavirus variant.
Health Minister Zweli Mkhize said on Sunday that the
government would await advice from scientists on how best to
proceed, after a trial showed the AstraZeneca vaccine did not
significantly reduce the risk of mild or moderate COVID-19 from
the 501Y.V2 variant that caused a second wave of infections
starting late last year.
Prior to widespread circulation of the more contagious
variant, the vaccine was showing efficacy of around 75%,
researchers said.
In a later analysis based mostly on infections by the new
variant, there was only a 22% lower risk of developing
mild-to-moderate COVID-19 versus those given a placebo. Although
researchers said the figure was not statistically significant,
due to trial design, it is well below the benchmark of at least
50% regulators have set for vaccines to be considered effective
against the virus.
The study did not assess whether the vaccine helped prevent
severe COVID-19 because it involved mostly relatively young
adults not considered to be at high risk for serious illness.
AstraZeneca said on Saturday that it believed its vaccine
could protect against severe disease and that it had already
started adapting it against the 501Y.V2 variant.
Still, professor Shabir Madhi, lead investigator on the
AstraZeneca trial in South Africa, said data on the vaccine were
a reality check and that it was time to "recalibrate our
expectations of COVID-19 vaccines".
South Africa hopes to vaccinate 40 million people, or
two-thirds of the population, to achieve some level of herd
immunity but has yet to administer a single shot.
It had hoped to roll out the AstraZeneca vaccine to
healthcare workers soon after on Monday receiving 1 million
doses produced by the Serum Institute of India (SII).
Instead, it will offer health workers vaccines developed by
Johnson & Johnson and Pfizer/BioNTech
in the coming weeks.
"What does that mean for our vaccination programme which we
said will start in February? The answer is it will proceed,"
Mkhize told an online news briefing. "From next week for the
next four weeks we expect that there will be J&J vaccines, there
will be Pfizer vaccines."
NEW APPROACH
Professor Salim Abdool Karim, an epidemiologist advising the
government, said there needed to be a new approach to
immunisations, given uncertainty about how effective current
vaccines would be against the 501Y.V2 variant.
First a vaccine should be used in a targeted group to assess
hospitalisation rates, and then if it proves effective in
reducing hospitalisations it could feature in a wide-scale
rollout, he said.
If it was not effective in reducing hospitalisations,
individuals who had received it should be offered another
effective vaccine, either a booster based on the variant or
another vaccine, Abdool Karim added.
It was probable that South Africa would experience a third
wave of infections when winter starts in around four months'
time, Madhi said.
He added that it would be "somewhat reckless" to discard the
1 million AstraZeneca doses the country had received when there
was still a chance they could protect against severe COVID-19.
Anban Pillay, health ministry deputy director-general, said
the expiry date on the AstraZeneca doses was in April, but the
government was speaking to the SII to seek an extension or
exchange.
Madhi said South Africa might want to reframe its target
group for vaccination. "It really needs to be centred around the
prevention of severe disease and death from what will likely be
a resurgence sometime soon."
(Reporting by Alexander Winning and Olivia Kumwenda-Mtambo;
Editing by Alexander Smith and Bill Berkrot)
Astrazeneca (AZN)
