Coronavirus: RDTs received for validation not sensitive enough – FDA

The Chief Executive Officer (CEO) of the Food and Drugs Authority (FDA) Mimi Delese Darko has revealed that none of the COVID-19 rapid diagnostic test (RDT) kits received so far meet the acceptable standards.

According to her, between 16 April 2020 and 17 July 2020, a total of 34 RDTs have been brought from China, United States of America, United Kingdom, Malaysia, Canada, Singapore, Korea and Finland for validation, however, none met the standards.

She explained that “the acceptable criteria are sensitivity and specificity of 99 per cent,” adding, “Taking all of them into consideration, we have a specificity of 85 to 99 per cent and a sensitivity of between 4 and 54 per cent.”

She made this known at the Information Ministry’s weekly press briefing on Tuesday, 28 July 2020.

Mrs Darko further intimated that the sensitivity of an RDT, once validated as acceptable by the ‘Gold standard’, has the capacity of identifying positive cases or those who have previously contracted the disease.

Those cases, per the sensitivity test, are known as “true positive.”

She added that as far as specificity is concerned, the kit identifies those who have not been exposed before, usually known as “true negative.”

Shedding more light on how validation is done, she said: “According to best international practice, all RDTs must be validated in the country in which they are going to be used and the population in which they’re going to be used. You would have heard that people will be bringing in RDTs from the US, from the UK.”

“You can't use it in this country unless they have been validated in Ghana for use.

“This validation is done with the Food and Drugs Authority in collaboration with the Noguchi Memorial Institute for Medical Research and with the Public Health Laboratory in Korle-Bu.”

She also said that validation in order to ascertain how highly sensitive or specific RDTs are is important because most often, some positive cases for COVID-19 do not show symptoms.

In view of this, she noted that “it is important to have highly sensitive RDTs.”