I’m confused about the dropping of the PCR test for travellers, with reliance being placed upon the LF test.
My understanding is that LF testing provides a useful indicator of the level of infection in a population based upon a statistically significant sample size taken from that population - but that it is unreliable as a test for infection in a single individual. For an accurate test for the presence of the virus you have to take a PCR test.
Have I got that all wrong.
Nope, you aren't wrong. LFTs are quick, convenient and cheap. People who do not have the lurgy are very unlikely to test positive, but people who do have the infection, especially if quite recent and viral levels are low, may not test positive. So you don't unnecessarily impose restrictions on people who don't need them, but you miss doing so on some people who do need them. That is not a major concern for epidemiological prevalence studies, not so great for testing people 'for cause', whether due to symptoms or high risk exposure.
The LFT is therefore the 'do something because we can't be seen to do nothing' test, whereas the PCR is the 'we really want to play this safe' test.
It is all driven by the travel industry lobbying to remove obstacles to people travelling, not based on a desire for accurate test results. I get this. Our family loves their overseas holiday and my boys are at ages where it is a great experience for them. We went away in summer 2019, but not 2020 or 2021, and that is a long time for a 11 or 13 year old. We would have loved
to go somewhere this year but decided it just wasn't work the risk of getting stuck somewhere due to an outbreak or change in regulations. So I get it, but it could be a rather short-sighted strategy, and the unavoidable assumption must be that The Man is prepared to tolerate a certain level of endemic virus if it takes some of the business pressure off. The problem is it is rather hard to know what level of endemic virus you are going to get.