It’s a new virus - not in an optimal state upon “birth” as it leaped into humans.
Has so much room to grow and ‘learn’
Increases in transmission rates and evasion of immunity should be expected.
We can anticipate and act accordingly.
1/x
We can start now to think through new vaccine designs that are not all narrow number of epitopes (in this case single [important] protein) and essentially identical to each other.
We can start “future proofing” our vaccine design choices to reduce immense risk of escape.
2/x
We can also immediately start building an Arsenal of contingency plans.
Tools that will not be susceptible to the same risk of mutants escaping immunity that arise from the ecological pressures from vaccines and infections....
3/x
Perhaps the most important contingency plan tool the world can build is something to give people knowledge of their infection status, in real time, and empower the public to take a deep role in stopping this public health problem.
Rapid at-home tests can do this.
4/x
Rapid home tests (to be used privately) are being built and new innovations are forthcoming at fast pace to accelerate their accessibility.
Should our vaccine efforts go sideways (I hope not, but we should plan for it given what’s on the line), home tests will be crucial.
5/5
Here’s at least one iteration of how this can work.
The recent @bmj_latest articles by @deeksj et al deriding Rapid Ag Innova Tests are simply WRONG
They simply do NOT appropriately interpret Ct values & do NOT consider massive importance of how long PCR remains + post-infectiousness
Inspection of Ct values among the Asymptomatics & correlation to RNA copies / ml shows Ct values in Liverpool are ~8 lower than often seen in literature. The failure to recognize this means the estimates of Ag test sensitivity for "high virus" are totally off.
2/x
The sensitivity for "moderately high" or "high" viral loads in the Liverpool data are ~90% and ~100%.
But to know this you cannot just assume a Ct of 25 elsewhere (often described as entering "high viral load") means same thing as a Ct value in other labs.
3/x
Unlike antibiotics where resistance happens w partial doses, to be a risk you also must be taking them in first place.
When considering escape from spike protein derived immunity - must consider everyone w/out sterilizing immunity at risk to induce a mutant upon infection.
2/x
Whether no vaccine or a single dose (or two) people create antibodies against the same part of the protein.
If discussing “partial immunity” or low affinity antibodies, must consider that a fully naive person might pose greater risk for escape than a single dose person
3/x
ALL evidence - when evaluated appropriately! - shows these are VERY good at detecting infectious virus
• ~100% if used frequently
• >95% for single samples with high, most likely contagious viral loads
The tests work
We've been evaluating rapid Ag tests on campuses. We find these tests - when used as screening w/out symptoms DO miss most PCR positives!
BUT EXPECTED! - ALL misses were previously detected and already finished isolation.
Ag is MUCH more specific than PCR for contagious virus
this is the whole point of rapid antigen tests - they find people who are currently infectious. They are fast, give crucial immediate results and unlike PCR do NOT stay positive for weeks/months after someone is no longer infectious.
The details are difficult to describe via Twitter but I’ve tried on many occasions. The described low accuracy is false. These tests are doing very well to catch infectious people. We do NOT want to detect and isolate people who are not infectious and just have old remnant RNA.
I know people want to hate on the government for purchasing tests - but the Innova test is working entirely as expected. Very good for detecting contagious people. Which is the only goal here.
I’d be happy to write an OpEd for @guardian to explain.