Pfizer and BioNTech expect to produce up to 50 million doses of their COVID-19 vaccine candidate globally this year and up to 1.3 billion doses by the end of 2021 [File: Dado Ruvic/Reuters]

Trinidad and Tobago, with a menu of vaccines now available, may be facing the expiration of tens of thousands of the Pfizer/BioNTech COVID-19 vaccine and Oxford/AstraZeneca doses come November.

This comes amid calls from the Government and health officials for people to come forward and take the vaccines, as the country still remains some way off from herd immunity.

The country received its first 2,000-dose donation of Oxford/AstraZeneca vaccines from the Government of Barbados seven months ago and since then has received 277,330 doses of the Oxford/AstraZeneca COVID-19 vaccine, 1,105,000 doses of the Sinopharm vaccine, 108,020 Johnson & Johnson vaccine doses, and 305,770 Pfizer/BioNTech vaccine doses.

T&T’s first doses of the Pfizer-BioNTech vaccine arrived from the United States on June 13, 2021. However, it was allocated exclusively to the arms of the Ministry of National Security and not the general public.

On August 12, 2021, the first tranche of 305,370 doses of the Pfizer COVID-19 vaccines arrived, out of a total of 907,920 doses donated by the United States government to T&T.

Children between 12 and 18 years old were the first eligible for the Pfizer jab, with doses administered from August 18. On August 23, the Director of Women’s Health, Dr Adesh Sirjusingh, at a virtual COVID-19 briefing, announced that from August 28, women in their second and third trimesters were eligible for the inoculation.

However, due to slow uptake and the looming expiry date on the Pfizer vaccines, Minister of Health Terrence Deyalsingh announced that teachers and healthcare workers would be eligible for the Pfizer vaccine from August 29.

The rollout was then further expanded to the public, anyone over 18 years old, from September 4, with 50,000 of the 305,370 doses allocated for this group of people, ensuring vaccines for the nation’s children.

Since Pfizer became available, it has accounted for over 50 per cent of first doses administered since August 18.

Daily first-dose data shows that the Pfizer vaccine has had the highest uptake since August 18.

As of September 13, there have been 53,472 first doses of the Pfizer jab administered and over the last four days, 15,352 people would have received their second dose.

However, the daily uptake has been variable, peaking at 3,891 first doses on September 8 but as low as 837 first doses on August 1.

The Oxford/AstraZeneca uptake has significantly dropped off since mid-August.

Since August 18, there were 5,152 first doses administered, accounting for 0.6 per cent of all first doses since. There were also 3,577 people becoming eligible for their second doses during this period.

By the end of November, Trinidad and Tobago could be losing Oxford/AstraZeneca and Pfizer-BioNTech COVID-19 vaccines off the existing menu of COVID-19 inoculations available.

From all shipments of the Oxford/AstraZeneca, T&T has remaining doses from the Canadian donation of 82,030 and 33,600 doses from the last COVAX shipment on August 11.

From the Canadian donation, 31,330 doses were used before expiration at the end of August 2021. The remaining 50,700 doses are expected to expire at the end of October 2021. Doses received from the third shipment of COVAX will also expire at the end of November.

For Pfizer, the donated 305,370 doses will expire sometime in November, with Prime Minister Dr Keith Rowley giving a deadline of October 14 through 17 to get the first dose and ensure a second dose will be available unexpired.

Given the second dose of Pfizer, the vaccine would need to be administered 21 days after the first dose, placing the expiry date in the ballpark of November 8, 2021.

Using the seven-day rolling average for Pfizer’s first doses of 2,100 doses per day and 34 days remaining until the October 17 deadline, T&T could administer 142,800 doses between first and second shots, resulting in 57,536 doses expiring.

It should be noted that using this rolling average estimate is crude, as daily uptake widely varies. Unless there is a marked change in vaccine hesitancy, daily uptake could decrease.

Guardian Media has reached out to the Ministry of Health for official projections on the number of vaccines the country may have to dispose of come November, as well as if there are plans to donate vaccines in stock to neighbouring Caricom nations. As of press time, there was no response.