(06-10-2021, 07:44 PM)danbrotherston Wrote: Presumably Delta could be tested for using the same PCR methods that all the other variants are selected for.
And presumably there *are* some numbers for it given that the government is making decisions based on us being a "Delta hotspot"...I'm just wondering why we aren't seeing the numbers.
The PCR tests use fluorescing reagents that are keyed to specific genetic sequences. Assuming they're using PCR testing for the mutations, the actual test output is just a yes/no on the N501Y mutation. Currently there's a small enough number of variants that a few specific yes/nos uniquely identify it, but only a full genetic sequencing can really tell what variant a given sample is from.
The delta variant is new enough we don't have tests available that are specifically keyed to its mutations, we can only identify it through genetic sequencing. Obviously however that takes time, and we don't have the capacity to do it to every sample.
What we can do though is read between the lines. My understanding is the Delta variant shows up ambiguously with other variants with the current mutation tests. Specifically, I think it shows up as the "Covid classic" variant, due to not having N501Y or E484K. Therefore if we see a sudden spike in original Covid, as if it suddenly started out competing B117, we can infer it's probably Delta. I believe that's what the province is going on for hot spots.