Dear Mr Pym,
Forgive this brief intrusion. I am a retired orthopaedic and trauma surgeon but I was trained at St Mary's which has been at the forefront of the analysis and cure of disease for many decades.
I applaud your detailed inquiry into this current case and in particular what surveillance took place at HR.
1. When there is incipient fever due to the toxins of bacteria, viruses, protozoa etc and in the shivery phase (vasoconstriction + muscle action > > fever) is it not the case that the core temperature might not be raised when the human first feels unwell? Measuring this nurse's temperature and finding it normal did not get round the fact that she reported she felt unwell. That was the key. I have not had time to check the literature.
2. The arrangements for the quarantine of UK nationals serving in Sierra Leone are casual at least. Infectivity is limited but the disease is fatal in up to 50% depending on existing nutrition etc. Furthermore the manner of dying is terrible. We can easily recall how this disease was reported on previously over four decades - blackest of the black. I believe that all UK nationals out there, who then plan to return, should be required to stay in small households, with no contact with locals, for the limit of the longest incubation period ie 21 days. What is happening instead is a very poor attempt at shutting the stable door when the virus has bolted. We heard the Save the Children Fund doctor say he had been to church there before his return! No hand shakes?
3. I noted a description about contact tracing of fellow airline passengers on one BBC link. Two rows in front and two behind. Relevant to droplet infection perhaps but is not the central factor here the toilets if disease was starting? I noted the low rate at present of contact chasing re the Casablanca to HR leg.
4. If anyone thinks the UK population is bursting with good health let them think of the homeless and the drug addicts - especially those who still needle share. There are thousands upon thousands of people with low resistance. Add to that those on oncotherapy. In spite of the vigorous reassurances of the Chief Medical Officer, Dame Sally, and others, the risk to this dense population is not 'very low'. Consider how sailors were dealt with over centuries. The fever flag would go up and the crew would stay at the mooring until the risk had cleared. The NY health authorities had a whole island for the purpose of isolation.
With best wishes and for truth
David Halpin MB BS FRCS