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Vaccination prospects boosted by Sisonke results and reversal on Astra-Zeneca jab

South Africa’s slow vaccination programme should get a boost from the highly encouraging results of the Sisonke clinical trial of the single-dose Johnson & Johnson vaccine against both the Delta and Beta COVID-19 variants, as well as new Health Minister Dr Joe Phaahla’s first major move following his appointment — the reversal of his predecessor’s controversial decision to discard the Astra-Zeneca vaccine, writes MedicalBrief.

The J&J shot was found in the Sisonke Implementation Study, the first real-world test of its efficacy against the Delta variant ravaging much of the world, had up to 95% against death and up to 71% against hospitalisation from the Delta variant, reported Professor Glenda Gray and Professor Linda-Gail Bekker last Friday (6 August). There was 67% protection against hospitalisation with the Beta variant.

The J&J vaccine demonstrated around 65% protection against hospitalisation for up to eight months.

The Sisonke trial evaluated the J&J vaccine in over 477,000 healthcare workers, who are at high risk of COVID-19, from 120 sites in both rural and urban areas between 17 February and 17 of May. The data have not yet been peer-reviewed.

The J&J shot probably more protective against dominant Delta than it was with the earlier Beta strain, said Gray, who is co-principal investigator of the study and president of SA Medical Research Council. She said the findings showed “remarkable protection” against hospitalisation and death.

“We believe this vaccine is doing what it was designed to do: to stop people going to hospital and ending up in ICUs and dying,” said Bekker, who is co-lead of the study and director of the Desmond Tutu HIV Centre at the University of Cape Town.

The results suggest those who have received one dose of the J&J vaccine donʼt need a booster shot, she said. In the rare cases when breakthrough infections did occur, around 96% of these were mild, 3% moderate, less than 0.05% severe and less than 0.05% resulted in deaths.

The Sisonke study recorded only two cases of the rare clotting disorder associated with the J&J vaccine but both participants made a complete recovery.

Around 1.8 million South Africans have been vaccinated with the one-shot Johnson & Johnson jab, while 6.7 million have received their first injection of the two-dose Pfizer vaccine.

A study conducted among Discovery Health members showed that the risk of hospitalisation due to the Delta variant was reduced by 39% in the 14 to 28 days after the first dose of Pfizer and by 77% seven days after the second dose. The vaccine also reduces the risk of getting infected with COVID-19 by 21% after the first dose and by 70% after the second dose.

South African will reintroduce the AstraZeneca vaccine as it has proven efficacy against the Delta variant of the coronavirus, Dr Joe Phaahla announced on Friday, the day after his appointment as the country’s new Minister of Health. The Sinovac vaccine would also be added to the programme.

 

Estelle Ellis in Daily Maverick, writes that more than a million doses of the two-shot vaccine, that was trialled in South Africa, among other countries, was initially purchased by the country to vaccinate health workers but former Health Minister Zweli Mkhize decided not to use them, as clinical trials had shown they were not particularly efficacious at preventing symptomatic infections by the Beta variant of the virus that was dominant in South Africa at the time. The trial leader, Professor Shabir Madhi of the University of the Witwatersrand, however always insisted that it would be effective in preventing severe disease and death.

Phaahla said he remained concerned about the outbreaks of coronavirus infections in the country.

He said they were especially monitoring the Western Cape and KwaZulu-Natal and was also worried that the Eastern Cape will “quickly be engulfed” by a third wave of infections.The Northern Cape was also not showing the decline in infections that they had hoped for.

Phaahla said due to supply constraints the daily number of vaccines administered were around 200,000 and 250,000 this week.
“We did have a dip, in the past week,” Phaahla said. “There was a shortage of supply. But I can assure you that this has changed in the past few days. There were 10m vaccine doses in fridges now and by the end of August, the country would have received 20m doses of the different vaccines.

Dr Anban Pillay, a deputy director in the national Health Department, said South Africa, in general, appears to be on a downward trajectory but the positivity rate was still high at 25.9%. The Western Cape has shown a steady increase in the number of new infections and has now surpassed Gauteng, and a similar, worrying trend was seen in KwaZulu-Natal.

In the Eastern Cape he said there was a significant increase in cases in Nelson Mandela Bay and the Sarah Baartman district but the province still only had moderate numbers of patients in hospitals.The Free State is showing an increase in infections across the board but as the third wave came through quickly after the second there appears to be sustained high levels of bed occupancy in the province’s hospitals.

He said KwaZulu-Natal is showing an increase in new cases, likely related to protests in the province that had become super spreader events but bed occupancy in hospitals were still “in the moderate zone”. Most districts in the Northern Cape showed increases in cases, Pillay explained, adding that the number of hospital admissions in this province was high. In this province funerals were a “big contributor” to the spread of infections.

The Western Cape, he said, was showing increases across all districts with the largest of these being seen in the Cape Town metro. Hospital admissions in the Western Cape remain high. Pillay said a recent spate of taxi violence in the province has contributed to the spread of the disease. “It is difficult to say if the Western Cape has passed the peak (of the third wave) as yet,” Pillay added, saying that the picture will become clearer in the next few days.

He said the modelled forecast for next week shows expected increases in the Free State, Eastern Cape and KwaZulu-Natal with continued increases in the Western Cape and the Northern Cape but declines in Limpopo, Mpumalanga and “a good decline” in the North West.

 

Department of Health: Sisonke Trial: Update on the Janssen (JNJ) Ad26.COV2.S vaccine by Professors Glenda Gray & Linda-Gail Bekker (Open access)

 

Full Daily Maverick article – Oxford AstraZeneca vaccine to make a comeback and provide a boos to national drive (Open access)

 

See more from MedicalBrief archives:

 

Sisonke: Only 2% of breakthrough infections in J&J vaccinated health workers are severe

 

Encouraging safety results from Sisonke trial of J&J vaccine in SA

 

J&J vaccine recipients may need boosters against Delta variant

 

Some experiencing side-effects from J&J vaccine

 

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