This is a round-up on the vaccines with the Delta variant as published by several countries....
The so called "real-world" data analysis of 14,019 cases of the Delta was released by PHE, found that BioNTech/Pfizer and Oxford/AstraZeneca vaccines were, respectively, 96 per cent and 92 per cent effective against hospitalisation after two doses.
But, whether the vaccines remain as effective at preventing infection, and therefore transmission and spread remains unclear.
Earlier in May, PHE claimed that two doses of the Pfizer vaccine were 88 per cent effective at preventing symptomatic infection with the Delta variant. A month later, that number was revised down to 79 per cent by Scottish researchers.
Last Saturday the Canadians announced that the Pfizer jab was estimated to be 87 per cent effective at preventing infection with the Delta variant.
"Against Delta, vaccine effectiveness after partial vaccination tended to be lower than against Alpha for BNT162b2 (56% vs. 66%) and mRNA-1273 (72% vs. 83%), but was similar to Alpha for ChAdOx1 (67%). Full vaccination with BNT162b2 increased protection against Delta (87%; 95% CI, 64–95%) to levels comparable to Alpha (89%; 95% CI, 86–91%) and Beta/Gamma (84%; 95% CI, 69–92%).
In particular, against Delta, vaccine effectiveness against severe outcomes after 1 dose of BNT162b2, mRNA-1273, and ChAdOx1 was 78% (95% CI, 65–86%), 96% (95% CI, 72– 99%), and 88% (95% CI, 60–96%), respectively."
However, the Israelis reported that the Pfizer vaccine was much less effective against symptomatic infection with Delta, providing only 64 per cent protection.
Both Pfizer and Israeli health officials, however, were quick to caution that the study was based on preliminary and highly localised infection numbers, and had other methodological weaknesses. The small size of the epidemic in Israel was one of several “fudge factors” that could impact results.
Last week Pfizer mentioned that a third booster might be needed or their "Variant Specific" booster can be used after the trial stages.
Moderna has said its vaccine showed a two fold reduction in neutralising antibodies in lab tests against Delta.
J&J single-shot vaccine, said its jab elicited a higher level of antibody activity against Delta than it had in tests against the Beta variant, first identified in South Africa. It provided no precise figures but said the vaccine offered “durable protection” against the disease.
Gameleya - the developer for Russia’s Sputnik V have said it was “more efficient against the Delta variant of coronavirus . . . than any other vaccine that published results on this strain so far”, but provided no evidence to support the claim.
The Deputy Head of Chinese CDC mentioned that two Chinese vaccines were found to be less effective for variants. Sinovac spokesman Liu Peicheng that preliminary results based on blood samples from those vaccinated with its shot showed a three-fold reduction in neutralising effect against Delta.
PHE also states that while the data on efficacy against hospitalisation was generally positive, the vaccines’ ability to prevent the transmission of Delta was far less clear. “Delta is so much more infectious, it’s better at finding people who aren’t sufficiently immune and infecting them,”
Reliable figures will take a time to accumulate. Only then one can positively estimate the effectiveness against the variant.
The so called "real-world" data analysis of 14,019 cases of the Delta was released by PHE, found that BioNTech/Pfizer and Oxford/AstraZeneca vaccines were, respectively, 96 per cent and 92 per cent effective against hospitalisation after two doses.
But, whether the vaccines remain as effective at preventing infection, and therefore transmission and spread remains unclear.
Earlier in May, PHE claimed that two doses of the Pfizer vaccine were 88 per cent effective at preventing symptomatic infection with the Delta variant. A month later, that number was revised down to 79 per cent by Scottish researchers.
Last Saturday the Canadians announced that the Pfizer jab was estimated to be 87 per cent effective at preventing infection with the Delta variant.
"Against Delta, vaccine effectiveness after partial vaccination tended to be lower than against Alpha for BNT162b2 (56% vs. 66%) and mRNA-1273 (72% vs. 83%), but was similar to Alpha for ChAdOx1 (67%). Full vaccination with BNT162b2 increased protection against Delta (87%; 95% CI, 64–95%) to levels comparable to Alpha (89%; 95% CI, 86–91%) and Beta/Gamma (84%; 95% CI, 69–92%).
In particular, against Delta, vaccine effectiveness against severe outcomes after 1 dose of BNT162b2, mRNA-1273, and ChAdOx1 was 78% (95% CI, 65–86%), 96% (95% CI, 72– 99%), and 88% (95% CI, 60–96%), respectively."
However, the Israelis reported that the Pfizer vaccine was much less effective against symptomatic infection with Delta, providing only 64 per cent protection.
Both Pfizer and Israeli health officials, however, were quick to caution that the study was based on preliminary and highly localised infection numbers, and had other methodological weaknesses. The small size of the epidemic in Israel was one of several “fudge factors” that could impact results.
Last week Pfizer mentioned that a third booster might be needed or their "Variant Specific" booster can be used after the trial stages.
Moderna has said its vaccine showed a two fold reduction in neutralising antibodies in lab tests against Delta.
J&J single-shot vaccine, said its jab elicited a higher level of antibody activity against Delta than it had in tests against the Beta variant, first identified in South Africa. It provided no precise figures but said the vaccine offered “durable protection” against the disease.
Gameleya - the developer for Russia’s Sputnik V have said it was “more efficient against the Delta variant of coronavirus . . . than any other vaccine that published results on this strain so far”, but provided no evidence to support the claim.
The Deputy Head of Chinese CDC mentioned that two Chinese vaccines were found to be less effective for variants. Sinovac spokesman Liu Peicheng that preliminary results based on blood samples from those vaccinated with its shot showed a three-fold reduction in neutralising effect against Delta.
PHE also states that while the data on efficacy against hospitalisation was generally positive, the vaccines’ ability to prevent the transmission of Delta was far less clear. “Delta is so much more infectious, it’s better at finding people who aren’t sufficiently immune and infecting them,”
Reliable figures will take a time to accumulate. Only then one can positively estimate the effectiveness against the variant.
