**We can be extremely confident that a novel virus is spreading and being correctly detected by our tests**

I'm only going to address claim 2, because the other claims are likely correct but essentially irrelevant because if claim 2 is false the chain of reasoning promptly falls apart.

**The protocol discussed was tested, and designed, for sensitivity**

You can find the testing protocol developed by the Berlin group which includes Christian Drosten [here][1]. The first thing to understand about the protocol is that it is based on PCR amplification. PCR amplification is a common molecular genetic technique widely used around the world, it works by amplifying (that is producing _vast_ numbers of copies of) nucleotide sequences that are defined by a sequence before (the 'forward' primer) and a sequence after (the 'reverse' primer) the target stretch of DNA†. PCR will only amplify sequences that have regions that match very closely to these primers. But the protocol uses a more sophisticated and sensitive variant which monitors the amplification process in real time. This real time monitoring is highly sensitive to even single base mismatches in either primer.

The protocol is a three stage process. The first "screening" assay checks for a match in the "E gene" common to many Coronaviruses, the second "confirmatory" assay checks for a match in the "RdRp gene" which will pick up only sequences of coronaviruses very closely related to SARS-CoV-2, and the final "discriminatory" assay will match only SARS-CoV-2 out of all of the Coronaviruses which have been sequenced so far.

The primers chosen for these assay were developed by _in silico_ analysis of 375 virus genome sequences to identify sequences that have highly specific matches to SARS-CoV-2. It is possible for these _in silico_ analyses to be misleading, but for _three_ of them applied consecutively to mislead is extremely unlikely.

To confirm that the _in silico_ results were not misleading, they took bat faeces samples known to contain Coronavirus, cell culture supernatant samples from cells infected with known human coronaviruses, and clinical samples from 75 patients infected with a range of viruses and confirmed that no false positives were recorded.

So it is _extremely unlikely_ that this test is producing a high number of false positives due to the highly specific nature of the testing and the results of their validation steps.

**But it is not the only test being used anyway**

The WHO lists [a range of other diagnostic tests][2] used around the world. Remember that for the claim in the question to be true not just the Berlin test but all others must also be misleading.

**And the tests are strongly validated by genome sequencing**

Modern sequencing technology has allowed rapid sequencing of samples from around the world, these samples can be compared [to generate a phylogenetic tree][3] showing how it has mutated as it has spread. This data provides unequivocal evidence of the spread of a novel virus, confirming the results obtained by diagnostic testing.


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† The virus itself is RNA, but the first step of the process produces DNA (referred to as cDNA) from this RNA, and the amplification proceeds with this DNA.

  [1]: https://www.who.int/docs/default-source/coronaviruse/protocol-v2-1.pdf
  [2]: https://www.who.int/emergencies/diseases/novel-coronavirus-2019/technical-guidance/laboratory-guidance
  [3]: https://bedford.io/blog/ncov-cryptic-transmission/