‘No-swab’ Covid-19 test from OptiGene highly sensitive, UK says

LONDON — A type of COVID-19 test that can be taken without the need for a nose or throat swab has been found to be highly effective in identifying infectious cases, including for people not showing symptoms, the British government said on Tuesday.

The RT-LAMP tests, made by privately held British company OptiGene, have been studied in a pilot program in the southern English city of Southampton, where they were used to test some health service staff, as well as 55,000 people connected to the local university.

“We’ve shown through carefully conducted studies that the OptiGene LAMP test is fast, reliable and easy to use, and dependent on testing format can work directly with saliva samples, as well as with swabs,” said Sue Hill, chief scientific officer for England in the National Health Service’s Test and Trace program.

Faster test results

LAMP is short for loop-mediated isothermal amplification, the technology used to process the tests. The LAMP tests can produce results more rapidly than the commonly used gold standard polymerase chain reaction tests.

In the Southampton pilot program, the tests were used in four different configurations, involving swabs as well as saliva.

The health ministry said the LAMP tests were found to have a sensitivity of 79 percent and specificity of 100 percent, meaning they were effective in identifying the people who were infectious and most likely to transmit the disease.

“In samples with a higher viral load, the sensitivity of the test increased to 94 percent for saliva and 100 percent for swabs,” the ministry said.

Students in pilot test

Sensitivity indicates the proportion of people with a disease that test positive. Specificity refers to the proportion of people without the disease that have a negative test. The measures are also used to determine the levels of false positives and false negatives.

Keith Godfrey, a professor at University of Southampton’s Epidemiology Unit, who led part of the pilot, said take-up had been very high among students and reactions positive.

“The saliva LAMP project in Southampton has proved to be very easy for students to use, and is extremely popular with parents and staff,” he said.