[Exports_project_office] false positives

[Ivona Cetinic]

Hello team,

please take a look at the write up and tell me if this is an ok  - sorry it
took me this long, but i went deep into NHS and CDC dark web. Open to any
suggestions.



Couple of items that we have to address regarding covid testing. You will
be tested 3 times using lateral flow test(LFtest) and 2 times using
classical PCR. While samples for PCR will be collected by the medic,
lateral flow test will be self-administered, and read. LFtests are in UK
used to track asymptomatic infections and currently recommended by UK
government to be conducted twice a week.

But before that one – let me address policy that we don’t have in place and
we should have – false positives.

What do we define here as false positives?

a)       False positives due to the test inherent capabilities to detect
the presence of the targeted substance – in case of PCR test probability of
such false positive is small (<1%) and for lateral flow test a bit higher
(<3%)

b)      “False positives” sensu previous infection. Both CDC and NHS don’t
recommend testing in people who had a Covid-19 infection in the last 90
days, as it has been demonstrated that these individuals can test positive
without being infectious or sick, and it is not considered a new infection
(however, our protocols are requiring us to do testing).

In our health plan, we have previously addressed the protocols in case
anyone starts feeling ill during the quarantine (B.3.1). However, if
participant is asymptomatic (especially with our vaccination rates), and we
have a positive test we will do following:

1)      In case your LFtest comes positive, you will immediately notify
Ivona, maintain strict isolation. LFtest will be repeated immediately 3
times. As per recommendations of NHS - following the conversation with
them, that person will be immediately be tested additionally with PCR test
as well. We will notify (with help of NOC) local authorities, and present
them with the results of the tests, your health screening documents and
your vaccination card. If there was a previous infection within the last 90
days, you will present those documents as well.

2)      In case your PCR test comes positive, you will immediately notify
Ivona (I will probably know before you), maintain strict isolation. Local
authorities will probably know as well. We will immediately do 3 lateral
flow tests (as we have them in the house), and will repeat the PCR test (if
approved by local health authorities), suggesting double sample collection.
Once in contact with authorities, you will present them with the results of
the tests, your health screening documents and your vaccination card. If
there was a previous infection within the last 90 days, you will present
those documents as well.

Final decision is whether this is a “false” positive or not will be given
by local authorities, and the project will proceed following their
recommendations, and procedures outlined in the EXPORTS health protocol.
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://espo.nasa.gov/pipermail/exports_project_office/attachments/20210413/c944d00f/attachment.html>