By Sue-Ann Wayow
TRINIDAD and Tobago has not yet received herd immunity against the Covid-19 virus although having lower transmission of the virus.
This is according to epidemiologist Dr Avery Hinds.
Dr Hinds explained that even with the current vaccination numbers, herd immunity will be achieved when the virus will not be able to be transmissible to other members of the population.
He was speaking on Wednesday during the Ministry of Health’s Covid-19 update.
As the virus mutated and became more transmissible, the goalpost for herd immunity has moved, Dr Hinds said.
He said, “Herd immunity is really when you get to a stage where the virus is really unable to continue to propagate itself through the population because of the proportion of immune individuals. Lots of things affect that including how long people remain immune quite apart from the transmissibility of the virus.”
Dr Hinds said, “At this point where we are still seeing a rolling average as at yesterday’s date, 231 people a day on average being infected, we know we are not at herd immunity. We are still seeing infections being propagated, we are seeing it being propagated at lower levels than previously, and we are happy about that, but herd immunity is still not something that we would have yet achieved.”
Using measles as an example, he said even if there was an imported case, it does not propagate, “that’s herd immunity.”
But to achieve that, it means that at least 95% of the population needed to have been vaccinated and immune.
Currently, Trinidad and Tobago population is 50.7% vaccinated against Covid-19 with 709,471 persons being considered fully vaccinated.
Dr Hinds said, “The more transmissible the virus, the higher the herd immunity needs to be to get to the point where there is no transmission.”
