Your article on test and trace deals solely with the failing system in England (Outsourcing firms miss 46% of Covid contacts in England’s worst-hit areas, 21 August). Here in Wales, the Labour government took the decision to devise its own system, which used local staff to carry out the contact work. Initially they used furloughed local-authority staff and, as some of these have been returning to their former roles, are now recruiting new people.

Almost 90% of positive cases have been reached and asked to provide details of their recent contacts, and 90% of close contacts have been given advice. This has meant that where there have been local outbreaks – on Anglesey, for example – they have been contained effectively. This has not involved masses of taxpayers’ money being paid to private firms for a failed system.
Janet Roberts
Saundersfoot, Pembrokeshire

• Last Thursday evening, because of my symptoms, I was advised by two medics working incredibly hard in the Covid-19 field that I should immediately have a test. The government website refused to offer me a home test and, similarly, after calling 119 and spending 30 minutes on the line, I was told I could not get one. My options were to (1) walk seven hours to the nearest test centre, (2) get someone in a car with me coughing all over them to drive me to a test centre 40 minutes away, or (3) take an hour’s bus journey to the nearest testing centre.

It is apparent that the opinion of medics is irrelevant, that the website and other administrators know best. The system that Matt Hancock and Dido Harding are responsible for (and for which she has £10bn of taxpayers’ money to spend) is what we have to follow. They both have no medical training and this underlies the incompetence.

It is appalling that this farce has forced me to potentially infect others. People will not get tested if this incompetent approach continues – and we will all suffer.
Dr Alan Gadian
Sidmouth, Devon

• Another reason that only “28% of people testing positive for Covid-19 reported any evidence of symptoms” (England to expand coronavirus infection survey to 150,000 people, 19 August) is the dawning realisation that when active infection is uncommon, as in the UK currently, a substantial proportion of “positives” are in fact “false positives” in people who are not actually infected.

This is because no test is perfect in the real world, even if it is in the laboratory. Fortunately, the people who really are infected are much more likely to test positive on an immediate second test. Retesting is therefore essential to avoid badging people as infected when they are not, with all that this might mean – for example, unnecessary isolating, contact tracing, and closing schools and workplaces.
Prof Charles Warlow
Prof Cathie Sudlow
Edinburgh

• Replacing quarantine with airport tests is not a good idea (Heathrow’s rapid Covid test centre ‘could replace quarantine’, 19 August). Covid-19 has an incubation period of between two and 13 days. A negative test at the airport may mean you are still incubating the virus. You may have just been exposed that day.

As a contact tracer myself, I have spoken to a number of people who developed Covid-19 the week following their return from abroad. Fortunately, they were under quarantine, so fewer people were exposed. If you don’t want to quarantine, stay home.
Wendy Roger
Bradford on Avon, Wiltshire

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