It is really important that people understand their part in TTIS (test, trace, isolate and support)…
Have you or someone you live with had a cough or other symptoms and been tested for Covid-19?
Was it made clear that all of you - all the people you live with - should stay at home and avoid contact with others from ASAP after the symptoms started, for…
…for 10 days after the onset of symptoms (the person with symptoms), 14 days for "contacts" (the other people in the household), or until a negative test result is received? And…
…and that if any member of the household is vulnerable, you should all do all you can by avoiding being in the same room, increased ventilation and handwashing, etc?
…The reason this is important is that
Some contacts will be infected and become cases
Most cases have few if any symptoms BUT are infectious; and
Those that do are most indeed ctios before symptoms show…
People become infectious quite soon after being infected. So it's vital that all contacts if possible cases self-isolate immediately.
…
I've recently heard from several households where somebody was tested, and the people they lived with thought they could carry on as normal, at least until a positive test result was received.…
If people aren't being informed clearly what they must do, then the most critical part of TTIS - I, for Isolate - is not happening, so of course case numbers are rising…
Where can I find definitions of "sterilising vaccine" and "neutralising vaccine"?
2/ Nobody has replied, and I can't remember what I was reading that prompted the question. So I'll say what I think the answer is!
At least for "sterilising vaccine" (or, if you use US spelling, "sterilizing vaccine".
3/ A sterilising vaccine is one which provides sterilising immunity.
"Sterilizing immunity means that the immune system is able to stop a pathogen, including viruses, from replicating within your body." thehill.com/changing-ameri…
Following on my marathon thread on testing ( threadreaderapp.com/thread/1308088… ), some thoughts on the app, which is due to be launched this week.
1/9
Most people with Covid-19 will never be identified.
Most never have symptoms. Few will be tested, and the test misses 70% of sick people, and even more of those without symptoms.
2/9
Which means, the app will only ever identify a fraction of people with Covid-19.
So not having been alerted that you've been in contact with somebody who might be infectious won't mean you haven't been.
Diagnosis of SARS-CoV2 is far from straightforward. It includes-
Identifying cause of new, significant illness.
Identifying people who are potentially infectious.
Identifying people with late complications.
We are particularly concerned, now, about identifying people who could infect others.
Difficult, since most infections are in people with no or minor symptoms.
This may explain the clamour for tests.
But tests are very poor at identifying these people.
We know that - in sick adults - a single PCR tests will miss >=30% of cases. (Two tests will still miss >=20%.) In asymptomatic but infectious people it will miss more of the cases; and it cannot detect people who have been infected, but are not yet infectious.
Particularly since I've been reporting via covid.joinzoe.com for weeks.
1/9
Interesting to hear more about the wide range of symptoms you can get. The classic 3 symptoms at eg gov.uk/government/pub… were the most discriminatory symptoms in people I'll enough to be admitted to hospital.
2/9
In milder cases - and especially in children - other symptoms are as or more common. Eg fatigue, loss of appetite (skipping meals), rashes, diarrhoea.
3/9
I was just asked to comment on Coronavirus vaccines. I thought twitter might be interested in my response.
There are many different vaccines in production, and for a vaccine geek like me, it’s fascinating.
1/7
I was saying that the future of vaccines was likely to be in DNA/RNA vaccines two decades ago – and then they almost disappeared off the radar, apart…
2/7
…apart from some trials of cancer vaccines (cleverly providing personalised cancer cell marker genes with conjugate molecules, effectively tricking the body into manufacturing a ready-conjugated vaccine).
3/7
Now that we are routinely testing lots of people - including care home staff and residents, and NHS staff - we are picking up positive results in asymptomatic people.
1/17
Where these are genuine cases, this is good.
The problem is many are being detected in people who had tested positive previously.
tldr: each time you run a "cycle" you double the amount of RNA in the sample. The number of times you do it is called the "cycle threshold" "Ct) ; the more often you have to do this before you can detect it, the less RNA there must have been in the original sample.
3/17