NO VACCINE WORRY
Figueroa confident WHO will authorise Astrazeneca jab despite South African delay
ONE of Jamaica’s foremost public health experts, Professor Peter Figueroa, is confident the development regarding the delayed roll-out of the Astrazeneca/ Oxford COVID-19 vaccine in South Africa will not negatively impact the World Health Organization’s
(WHO) authorisation of the jab for use in countries that are part of the COVAX facility.
Professor Figueroa told the Jamaica Observer yesterday that concerns from South Africa stem from the variant of novel coronavirus found in that country and the reduced efficacy of the Astrazenca vaccine with the variant and its mutations. In addition, he said another concern is the extent of the Astrazeneca vaccine’s effectiveness in the elderly over age 65.
Yesterday, Agence France Presse (AFP) reported that South African authorities delayed the start of a much-anticipated vaccination campaign expected to begin this week with a first batch of one million Astrazeneca/oxford doses
after a study showed the jabs failed to prevent mild and moderate infection from the South African variant.
The French news agency further added that the temporary suspension, announced late on Sunday, put a damper on the imminent roll-out and stoked criticism of the novel coronavirus response in Africa’s hardest-hit nation.
South Africa’s top government advisor and leading epidemiologist Salim Abdool Karim said his team had suggested still using the Astrazeneca shots in a more staggered manner starting with a smaller population group and closely studying their response.
Karim added that it was “prudent” to push back the wider distribution of Astrazeneca shots until scientists ascertain whether they could still prevent severe disease, hospitalisation and death. However, he assured that delay would be “partially compensated” by another batch of vaccines developed by US drugmaker Johnson & Johnson expected to land next week.
But Professor Figueroa, who is also part of the WHO’S working group for COVID-19 vaccines, explained that the WHO has been closely monitoring the Astrazeneca data and assessing it to judge the question of emergency authorisation. He said many countries, like Jamaica, that are part of the COVAX facility, hinge on that authorisation in order for the vaccine to be released and thereafter received.
Subsequently, Professor Figueroa said, based on the meetings he has attended and the data that exists, the overall efficacy or performance of the vaccine under ideal and controlled circumstances is satisfactory. He is therefore confident that the WHO will give the green light so that other countries can begin roll-out of the vaccine.
“My assessment is that the WHO will authorise use of the Astrazeneca [vaccine] because the overall efficacy is satisfactory. The efficacy is with one dose, and this efficacy increases with the interval between the first and the second dose. The efficacy improves between four and 12 weeks, being higher at 12 weeks. Now, because this trial enrolled the elderly fairly late in the trial, they do not have enough data to say that the vaccine is efficacious in the elderly over 65. But when you look at the immune response in the elderly and compare it to the younger adults, the immune response for those elderly who they do have in the trial and were given the vaccine is similar. Therefore, the experts, I think, are likely to simply say that the vaccine is appropriate for use in the adult population over 18 years, including the elderly,” he said.
Of note, Professor Figueroa said in vaccines that have shown higher efficacy
Pfizer/biontech and Moderna no one has said anything about efficacy in the over 80-year age group, even though they have been administered to people over 80 years. He said, though the sample may not allow for great sub-analysis, the available immune data suggest effectiveness.
“You may not have enough patients over the age of 80 to say that you show efficacy in that age group, but you have enough to show that it is over 65. The trend shows efficacy in the elderly and the immune data support giving it in the elderly,” he said.
In relation to lower efficacy vaccines, the public health expert said evidence still supports administering shots as some amount of reduction in virus potency will occur.
“The modelling data show that even if you have a vaccine of much lower efficacy than the current vaccines, given the pandemic, it still makes a lot of sense to use a vaccine with low efficacy, because it would reduce the number of persons getting severely ill,” he said.
“The data for Astrazeneca show that there are very few hospitalised cases or severe cases in the vaccine group for Astrazeneca, and there are no deaths for persons who got the vaccine. There are very few severe cases of COVID in the vaccine group. So, we are confident this is a vaccine that would be very useful to use in most populations, and I would say the Jamaican and Caribbean populations,” he said.
Further, Professor Figueroa pointed out that South Africa’s decision must be viewed in the context that they are seeking to get an alternate vaccine available for their population.
“I did see an item saying they would prefer to get the Johnson & Johnson vaccine, which seems to respond better to the variant they have, and it’s currently just one dose of the Johnson & Johnson vaccine, whereas it is two doses for the Astrazenca. Their assessment is also taking into consideration the fact that they are likely to have access to another vaccine,” he said.
In the meantime, Professor Figueroa maintained and reaffirmed his support for the vaccine, and confidence that the WHO will suggest the vaccine is fine to be administered.
“This is a variant that developed in South Africa, which, although it has been identified elsewhere, so far we don’t know if we have it in Jamaica. We do have the variant that came out of the UK, but the South Africans are very familiar with their situation. They have been monitoring the variants, they have been doing clinical trials, they have a good cadre of outstanding scientists. So I would respect the decisions they are taking,” he said.