Citizens are being advised to still wear their masks and social distance, even after taking the COVID-19 vaccine.
In March, T&T will receive over 100,000 Oxford-AstraZeneca vaccines but Professor Peter Figueroa said even with this roll out protocols should be adhered to.
"We still do not know for sure what is the level of reduction in transmission of the virus when you are vaccinated," Figueroa said.
The chairman of PAHO's Regional Immunization Technical Advisory Group was speaking during a COVID-19 question and answer session hosted by the" University of the West Indies on Monday.
Data shows that AstraZeneca is 76-82 per cent effective in preventing symptomatic infection after three months after the first dose. While Pfizer and Moderna have a higher efficacy of over 90 per cent.
But Professor Christine Carrington said all the vaccines are on the same level and so far showed exceptional efficacy against hospitalisation and death.
"They are all performing very well...resent data from Scotland which showed that there was a 94 per cent reduction in hospitalisations among the elderly who was the first to receive the vaccine in Scotland that's the AstraZeneca," Carrignton said.
Carrignton added that the logistics of storage for the AstraZeneca are easier. And while the bill of the vaccines should be footed by the Government the AstraZeneca is the cheapest among the approved vaccines by the World Health Organisation at five US dollars.