Oxford study shows none of UK’s validated antibody tests have performed well
NASSAU, BAHAMAS — As the government seeks to increase testing capacity to capture more positive COVID-19 patients and limit local spread, Deputy Chief Medical Officer Dr Delon Brennen said today that health experts were exploring new technology that may facilitate expanded diagnostic testing in The Bahamas.
Polymerase chain reaction (PCR) or diagnostic testing remains the gold standard as opposed to antibody or rapid tests.
“We would love to be able to expand testing, and I think for us, we love to actually expand to a rapid form of PCR testing, which is probably the better way we would love to do it — to be actually able to detect the virus, just infected, a little bit faster,” Brennen told Eyewitness News.
“There is some technology that is out there that we’re exploring that we may be able to actually see that.”
As of last week Wednesday, nearly 400 people had been tested for the virus.
At the time, there were 40 confirmed cases of the virus and seven people had died.
National HIV/AIDS and Infectious Disease Programme Director Dr Nikkiah Forbes said the high case fatality rate was a reflection of the government’s ability to perform widespread testing, though capacity was being worked on.
As of this morning, there were 47 confirmed COVID-19 cases.
Eight people have died in total.
Asked when widespread testing could be performed, Brennen said: “We don’t have a specific date. We just have to collect enough samples because what you have to do is compare the positive PCR to what results you get; the rapid, antibody testing.
“And so, it just depends on how fast we accumulate cases that we’d be able to tell are the result concordant or discordant.
“If you get a positive on PCR and it correlates with a positive on rapid testing; and if you get negative of PCR and if that correlates with a negative of rapid testing, so we need to make sure the results match so we can rely on the results of the rapid.
“That’s what is ongoing right now, so we don’t have the results from that as of yet.
“As you would imagine or sample size is still pretty small, so we are only talking about 47 [cases].
“What we are also doing is looking at some of the results that some of the other countries with much larger case numbers are showing us.”
A University of Oxford research paper, published last Sunday, explored the challenges of antibody tests in the United Kingdom and noted that no antibody test to date has performed well.
It acknowledged that widespread large-scale testing is a crucial strategy, but a combination of testing strategies with a gold standard test, provides citizens and the health system with all the information needed to lower the risk of circulating the virus.
The paper written by Professor Sir John Bell noted that 100 or more test kits, including home test kits, were made available from varying suppliers to identify COVID-19 antibodies, but many false negatives and false positive continued to be observed.
“None of the tests we have validated would meet the criteria for a good test as agreed with the MHRA (Medicines and Healthcare products Regulatory Agency),” Sir John wrote.
“This is not a good result from test suppliers or for us.”
As of April 7, the UK, which has a population of over 66 million people, had performed just under 220,000 tests — less than 0.4 percent of its population.
According to media reports, the UK has not had the resources to do mass testing, though the government has aimed to carry out 100,000 test per day by the end of April.
In The Bahamas, the nearly 400 test performed as of last week Wednesday, puts the testing of the population percentage at around 0.1 percent.