6th Jan 2021 @ 8:51 pm

Sooner or later, there’s a chance you’ll need a test for Covid-19 – especially if you’re flying off-island in the near future. Here are the tests available, and what they do.

PCR tests

PCR tests use a swab sample to detect the presence of the virus itself, and are highly reliable, which is why they’re regarded as the “gold standard”. The drawbacks are : they need to be analysed in a laboratory, which makes them more expensive and delays results. TMA and LAMP tests are cheaper, faster variations on the PCR test which are not yet widespread.

Antigen test

A swab test which detects traces of proteins related to the virus. This means it is good at detecting infectious individuals., but it can also pick up traces of past infections. For this reason it’s less reliable, and may miss early cases or cause false positives. They are cheaper and faster, although some clinics have hiked prices.

Antibody test

A blood test that detects antibodies caused by exposure to the virus. This test is useless for travel, and can not tell you whether you have the virus or not – just whether you’ve had it in the past. It’s useful for measuring presence of the virus in communities.

At the time of writing, PCR tests remain the normal requirement for international travel, although some places have permitted antibody tests. Most EU countries, including Spain, are waiting to form a protocol on antigen tests before authorising them.

In the UK PCR tests on the NHS are free, but do not provide the necessary certification to fly because they are intended for genuine Covid suspects, not holiday makers.