Day: 9 September 2020

Dr Clare Craig FRCPath The Covid Pimpernel: They seek it here, they seek it there, those testers seek it everywhere. Is it in Leicester, or in Torbay, that damned elusive RNA. On 7th September Public Health England announced a change to testing criteria. The change is designed to address the problem of false positives, people that test positive but do not in fact have COVID-19. The consequences of these false positives stretch far beyond the inconvenience to an individual who has to self-isolate unnecessarily. Counting false positives when a disease is not very prevalent can result in misleading, fear-mongering news articles and mistaken health policies. The impact of this change in testing criteria is yet to affect the case numbers being reported. The new criteria means some cases will need further assessment before being reported so those results will be delayed.   Until Public Health England published this guidance, the working assumption was that false positive test results are irrelevant for testing carried out for COVID-19. This assumption is not true. However, in times of an epidemic, a few false positives does not make a material difference to the reported numbers of infected cases. When 30% of results are positive then 1% being false positive would be immaterial. When only 2% of your results are positive then 1% being false positive is important. ...

Panicking Boris Imposes Second Lockdown "Crikey Moses! I think we'd better press the panic button. What do you think, Dom?" Late on Tuesday night the Government announced a raft of new restrictions would be imposed in England from next Monday. The BBC has more. Social gatherings of more than six people will be illegal in England from Monday – with some exemptions – amid a steep rise in coronavirus cases.A new legal limit will ban larger groups meeting anywhere socially indoors or outdoors, No 10 said.But it will not apply to schools, workplaces or Covid-secure weddings, funerals and organised team sports.It will be enforced through a £100 fine if people fail to comply with police, doubling up to a maximum of £3,200. Don't imagine the "workplace" exemption applies to restaurants, pubs and cafes. According to the BBC: "The change applies to... gatherings indoors and outdoors, in private homes, public outdoor spaces, and venues such as pubs and restaurants." This is in response to the rise in cases in the community – 2,460 new cases on Tuesday – which, as I explained in the Telegraph on Monday, is an artefact of increased testing. In the past week alone there have been over 1.3m coronavirus tests, compared to just 95,188 in the first week of April. Testing has increased to 1.3 million in ...