# Coronavirus - Taiwan 2021 **URL:** \ **Category:** Living in Taiwan\ **Tags:** covid-19, 2021\ **Created:** [January 1, 2021, 7:56am UTC](https://tw.forumosa.com/t/coronavirus-taiwan-2021/200866 "2021-01-01T07:56:35Z")\ **Posts on this page:** 20\ **Page:** 4
**Author:** ![Belgian\_Pie](https://forumosa-12829.kxcdn.com/letter_avatar_proxy/v4/letter/b/8dc957/32.png) [@Belgian\_Pie](https://tw.forumosa.com/u/Belgian_Pie)\ **Post date:** [January 5, 2021, 7:43am UTC](https://tw.forumosa.com/t/coronavirus-taiwan-2021/200866/61 "2021-01-05T07:43:18Z")
> [@the\_bear](#): > > Please let’s not go down this road yet again… They just did. ---
**Author:** ![the\_bear](https://forumosa-12829.kxcdn.com/user_avatar/tw.forumosa.com/the_bear/32/192391_2.png) [@the\_bear](https://tw.forumosa.com/u/the_bear)\ **Post date:** [January 5, 2021, 7:45am UTC](https://tw.forumosa.com/t/coronavirus-taiwan-2021/200866/62 "2021-01-05T07:45:42Z")
It’s a testing merry go round. See the woman who just returned from the US and tested negative three times in the US but tested positive here. ---
**Author:** ![afterspivak](https://forumosa-12829.kxcdn.com/letter_avatar_proxy/v4/letter/a/ccd318/32.png) [@afterspivak](https://tw.forumosa.com/u/afterspivak)\ **Post date:** [January 5, 2021, 8:19am UTC](https://tw.forumosa.com/t/coronavirus-taiwan-2021/200866/63 "2021-01-05T08:19:33Z")
> [@Belgian\_Pie](#): > > If it’s not in Taiwan how can she export it? As the bear indicated, I think you must understand the drill by now. A worker from Vietnam goes home and tests positive upon arrival. Vietnam dutifully reports this to the Taiwan authorities. Taiwan authorities dutifully trace and test the contacts this worker had in her final days in Taiwan (in this latest case, seven people). Results then released (as per the Focus Taiwan article linked above, one of the seven contacts so far has tested negative). Guy ---
**Author:** ![the\_bear](https://forumosa-12829.kxcdn.com/user_avatar/tw.forumosa.com/the_bear/32/192391_2.png) [@the\_bear](https://tw.forumosa.com/u/the_bear)\ **Post date:** [January 5, 2021, 8:25am UTC](https://tw.forumosa.com/t/coronavirus-taiwan-2021/200866/64 "2021-01-05T08:25:17Z")
You forget the final step which is @SuperS54 posting “weak positive!” 😂 ---
**Author:** ![afterspivak](https://forumosa-12829.kxcdn.com/letter_avatar_proxy/v4/letter/a/ccd318/32.png) [@afterspivak](https://tw.forumosa.com/u/afterspivak)\ **Post date:** [January 5, 2021, 8:27am UTC](https://tw.forumosa.com/t/coronavirus-taiwan-2021/200866/65 "2021-01-05T08:27:04Z")
No, there is no final step here, as Belgian Pie will of course step up and ask: “If it’s not in Taiwan how can she export it?” Then we start all over again! Guy ---
**Author:** ![meishijia](https://forumosa-12829.kxcdn.com/user_avatar/tw.forumosa.com/meishijia/32/178949_2.png) [@meishijia](https://tw.forumosa.com/u/meishijia)\ **Post date:** [January 5, 2021, 8:28am UTC](https://tw.forumosa.com/t/coronavirus-taiwan-2021/200866/66 "2021-01-05T08:28:19Z")
So is the current thinking that she caught it in Taiwan, or she caught it abroad a whole ago and is still testing positive because it is still in her system? How long was she in Taiwan before leaving to go to Vietnam? ---
**Author:** ![the\_bear](https://forumosa-12829.kxcdn.com/user_avatar/tw.forumosa.com/the_bear/32/192391_2.png) [@the\_bear](https://tw.forumosa.com/u/the_bear)\ **Post date:** [January 5, 2021, 8:34am UTC](https://tw.forumosa.com/t/coronavirus-taiwan-2021/200866/67 "2021-01-05T08:34:01Z")
She’d been here four years. There’s been many of these cases. Never has a single contact been found to also have the virus. Hence the false positive meme. It could be dodgy testing or exposure en route home. ---
**Author:** ![meishijia](https://forumosa-12829.kxcdn.com/user_avatar/tw.forumosa.com/meishijia/32/178949_2.png) [@meishijia](https://tw.forumosa.com/u/meishijia)\ **Post date:** [January 5, 2021, 8:35am UTC](https://tw.forumosa.com/t/coronavirus-taiwan-2021/200866/68 "2021-01-05T08:35:36Z")
If she was exposed on her flight home, everyone on the flight would also have been in Taiwan during at least the previous two weeks, so either way Taiwan has more cases in the wild than we think. Unless of course it is a false positive. How does Taiwan CDC explain it? ---
**Author:** ![yinggeaussie](https://forumosa-12829.kxcdn.com/letter_avatar_proxy/v4/letter/y/c68b51/32.png) [@yinggeaussie](https://tw.forumosa.com/u/yinggeaussie)\ **Post date:** [January 5, 2021, 8:36am UTC](https://tw.forumosa.com/t/coronavirus-taiwan-2021/200866/69 "2021-01-05T08:36:57Z")
Does the 250,000 represent TW Citizens arriving from the USA after a lengthy absence from Taiwan, or something else? ---
**Author:** ![Brianjones](https://forumosa-12829.kxcdn.com/letter_avatar_proxy/v4/letter/b/eada6e/32.png) [@Brianjones](https://tw.forumosa.com/u/Brianjones)\ **Post date:** [January 5, 2021, 8:37am UTC](https://tw.forumosa.com/t/coronavirus-taiwan-2021/200866/70 "2021-01-05T08:37:24Z")
False positive rate is what…1 in a hundred ? Multiply by number of migrant workers going both ways Also can get infected enroute. Do a few close contact tests and don’t worry much more about it unless something pops up in the close contacts. ---
**Author:** ![the\_bear](https://forumosa-12829.kxcdn.com/user_avatar/tw.forumosa.com/the_bear/32/192391_2.png) [@the\_bear](https://tw.forumosa.com/u/the_bear)\ **Post date:** [January 5, 2021, 8:37am UTC](https://tw.forumosa.com/t/coronavirus-taiwan-2021/200866/71 "2021-01-05T08:37:26Z")
I think so. It’s a repatriation figure. ---
**Author:** ![RBE](https://forumosa-12829.kxcdn.com/letter_avatar_proxy/v4/letter/r/67e7ee/32.png) [@RBE](https://tw.forumosa.com/u/RBE)\ **Post date:** [January 5, 2021, 8:40am UTC](https://tw.forumosa.com/t/coronavirus-taiwan-2021/200866/72 "2021-01-05T08:40:40Z")
A lot of labs are using high Ct values when doing PCR testing. Some experts say that anything above 30 is questionable, and anything above 35 is downright dubious. In the US, I believe the default being used in many places is 37-40. Might partly explain why there are so many asymptomatic “cases”. ---
**Author:** ![TroubleWithTribbles](https://forumosa-12829.kxcdn.com/letter_avatar_proxy/v4/letter/t/d9b06d/32.png) [@TroubleWithTribbles](https://tw.forumosa.com/u/TroubleWithTribbles)\ **Post date:** [January 5, 2021, 8:50am UTC](https://tw.forumosa.com/t/coronavirus-taiwan-2021/200866/73 "2021-01-05T08:50:45Z")
> [@RBE](#): > > In the US, I believe the default being used in many places is 37-40. Might partly explain why there are so many asymptomatic “cases”. Yes, it is likely that some of the higher Ct values represent past infection with remaining viral fragments, especially more than a few weeks after symptoms. Labs do often use a cutoff of 40, but the tests are not technically quantitative so it is hard to give exact numbers. But if people getting tested for symptoms, you would expect more of that group to be truly positive than when you screen asymptomatic people. ---
**Author:** ![RBE](https://forumosa-12829.kxcdn.com/letter_avatar_proxy/v4/letter/r/67e7ee/32.png) [@RBE](https://tw.forumosa.com/u/RBE)\ **Post date:** [January 5, 2021, 9:10am UTC](https://tw.forumosa.com/t/coronavirus-taiwan-2021/200866/74 "2021-01-05T09:10:24Z")
Yes, it could be that the test is picking up remnants of a past infection. I also wonder about the RNA fragments being used for testing. Each testing kit producer can use different fragments. How do we really know that SARS-CoV-2 is the only virus with those fragments? We’re talking about really short sequences of RNA here. Already, there are some theories that parts of Asia, including Taiwan, have been less hard hit because SARS-like viruses have been spreading undetected for years without causing major illness. If that’s the case, it’s within the realm of possibility that there are other viruses that share the RNA the tests are looking for. ---
**Author:** ![TroubleWithTribbles](https://forumosa-12829.kxcdn.com/letter_avatar_proxy/v4/letter/t/d9b06d/32.png) [@TroubleWithTribbles](https://tw.forumosa.com/u/TroubleWithTribbles)\ **Post date:** [January 5, 2021, 9:30am UTC](https://tw.forumosa.com/t/coronavirus-taiwan-2021/200866/75 "2021-01-05T09:30:23Z")
> [@RBE](#): > > also wonder about the RNA fragments being used for testing. Each testing kit producer can use different fragments. How do we really know that SARS-CoV-2 is the only virus with those fragments? We’re talking about really short sequences of RNA here. Most of them use spike and another target. Sequence variations can throw the primers and cause false negatives in theory. They do test for cross reactivity with other viruses and very little has been found. Some tests may show limited cross reactivity with the previous SARS, but that is not in circulation. ---
**Author:** ![mortauxmoi](https://forumosa-12829.kxcdn.com/letter_avatar_proxy/v4/letter/m/e5b9ba/32.png) [@mortauxmoi](https://tw.forumosa.com/u/mortauxmoi)\ **Post date:** [January 5, 2021, 9:33am UTC](https://tw.forumosa.com/t/coronavirus-taiwan-2021/200866/76 "2021-01-05T09:33:55Z")
Apparently the government is now considering whether or not to allow Chinese students to enter Taiwan > **[獨》鎖國後境外生返台難題 6日跨部會討論 - 生活](https://www.chinatimes.com/realtimenews/20210105002905-260405?chdtv)** > > 英國傳出變種病毒，並入侵我國，指揮中心已宣布，元旦起禁止外籍人士入境，被視為是二度鎖國，各大學嚴陣以待，但陸生大表擔憂，認為又是突然宣布的決策，未通盤詢問與考量，尚未回台的陸生恐將無止境休學，對此教育 ---
**Author:** ![Brianjones](https://forumosa-12829.kxcdn.com/letter_avatar_proxy/v4/letter/b/eada6e/32.png) [@Brianjones](https://tw.forumosa.com/u/Brianjones)\ **Post date:** [January 5, 2021, 9:40am UTC](https://tw.forumosa.com/t/coronavirus-taiwan-2021/200866/77 "2021-01-05T09:40:42Z")
> [@RBE](#): > > How do we really know that SARS-CoV-2 is the only virus with those fragments? We’re talking about really short sequences of RNA here. Well there are good genomes available of the four endemic human coronaviruses . I’m guessing they do the usual blast search against all known genomes and exclude as many common sequence as possible. Then there are tecnqhiues to improve selectivity such as nested PCR. Latest one being promoted is isothermal amplification I’m interested to know how it’s working in reality. ---
**Author:** ![Brianjones](https://forumosa-12829.kxcdn.com/letter_avatar_proxy/v4/letter/b/eada6e/32.png) [@Brianjones](https://tw.forumosa.com/u/Brianjones)\ **Post date:** [January 5, 2021, 9:44am UTC](https://tw.forumosa.com/t/coronavirus-taiwan-2021/200866/78 "2021-01-05T09:44:00Z")
If I recall rightly the closest genome to SARS2 detected was actually identified and sequenced at WIV lab a few years ago . It has 96% homology and it’s a bat coronavirus from Yunnan thousands of KM away. And one asks how come SARS2 then somehow popped up in Wuhan first. Maybe it’s a massive coincidence and other labs haven’t really been looking A very very big maybe. [https://www.nature.com/articles/d41586-020-03217-0](https://www.nature.com/articles/d41586-020-03217-0) **Only a handful of known coronaviruses are closely related to SARS-CoV-2, including its closest known relative, RaTG13. That was discovered in intermediate horseshoe bats ( _Rhinolophus affinis_ ) in the Chinese province of Yunnan in 2013, and was published[2](https://www.nature.com/articles/d41586-020-03217-0#ref-CR2) only earlier this year. There are also several other coronaviruses, found in other _Rhinolophus_ bats and [pangolins](https://www.nature.com/articles/d41586-020-00548-w) captured between 2015 and 2019, that scientists now know to be closely related to SARS-CoV-2.** **“SARS-CoV-2 probably wasn’t a brand new virus that popped up all of a sudden. Viruses in this group existed before we became aware of them in 2019,” says Tracey Goldstein, associate director of the One Health Institute at the University of California, Davis, who is involved with the Cambodian team.** **Latinne says the discoveries confirm that _Rhinolophus_ bats are the reservoir of these viruses.** Horseshoe bats are almost certainly the reservoir species. ![smoking-gun-18033974](https://forumosauploads-12829.kxcdn.com/original/3X/a/6/a64eb901479de1ec5d8e892b808e32cd391fe838.jpeg) ---
**Author:** ![Brianjones](https://forumosa-12829.kxcdn.com/letter_avatar_proxy/v4/letter/b/eada6e/32.png) [@Brianjones](https://tw.forumosa.com/u/Brianjones)\ **Post date:** [January 5, 2021, 10:03am UTC](https://tw.forumosa.com/t/coronavirus-taiwan-2021/200866/79 "2021-01-05T10:03:35Z")
More background on similarity from their Feb paper. Takeaway from this is that there are no similar coronaviruses in circulation that could reasonably present a false positive as long as the PCR test is calibrated correctly. Covid19 is quite distinct even from other SARS-Coronaviruses. **We then found that a short region of RNA-dependent RNA polymerase (RdRp) from a bat coronavirus (BatCoV RaTG13)—which was previously detected in _Rhinolophus affinis_ from Yunnan province—showed high sequence identity to 2019-nCoV. We carried out full-length sequencing on this RNA sample (GISAID accession number EPI\_ISL\_402131). Simplot analysis showed that 2019-nCoV was highly similar throughout the genome to RaTG13 (Fig. [1c](https://www.nature.com/articles/s41586-020-2012-7#Fig1)), _with an overall genome sequence identity of 96.2%._ Using the aligned genome sequences of 2019-nCoV, RaTG13, SARS-CoV and previously reported bat SARSr-CoVs, no evidence for recombination events was detected in the genome of 2019-nCoV. Phylogenetic analysis of the full-length genome and the gene sequences of _RdRp_ and _spike_ ( _S_ ) showed that—for all sequences—RaTG13 is the closest relative of 2019-nCoV and they form a distinct lineage from other SARSr-CoVs (Fig. [1d](https://www.nature.com/articles/s41586-020-2012-7#Fig1) and Extended Data Fig. [2](https://www.nature.com/articles/s41586-020-2012-7#Fig5)). The receptor-binding spike protein encoded by the _S_ gene was highly divergent from other CoVs (Extended Data Fig. [2](https://www.nature.com/articles/s41586-020-2012-7#Fig5)), with less than 75% nucleotide sequence identity to all previously described SARSr-CoVs, except for a 93.1% nucleotide identity to RaTG13 (Extended Data Table [3](https://www.nature.com/articles/s41586-020-2012-7#Tab3)). The _S_ genes of 2019-nCoV and RaTG13 are longer than other SARSr-CoVs. The major differences in the sequence of the _S_ gene of 2019-nCoV are the three short insertions in the N-terminal domain as well as changes in four out of five of the key residues in the receptor-binding motif compared with the sequence of SARS-CoV (Extended Data Fig. [3](https://www.nature.com/articles/s41586-020-2012-7#Fig6)).** PS - It seems they never published any data from RaTF13 previously even though it was first identified in 2013. They say it’s because they never sequenced it fully, only had a sub sequence…Maybe… ---
**Author:** ![Icon](https://forumosa-12829.kxcdn.com/user_avatar/tw.forumosa.com/icon/32/189245_2.png) [@Icon](https://tw.forumosa.com/u/Icon)\ **Post date:** [January 5, 2021, 11:38am UTC](https://tw.forumosa.com/t/coronavirus-taiwan-2021/200866/80 "2021-01-05T11:38:07Z")
I suspect a bit of both. We got the champion, the woman who had stayed away from Taiwan nearly 40 years …and lo and behold, was found to be sick on arrival. Then we have the last two cases. One arrived there in September and hit jackpot. We got students whose schools went virtual. We got students and workers and residents who got spooked. We got workers who were stranded and had to wait for repatriation flights. Others risked it for business sake. All came back here because it is safer… unless you ask my neighbors. I actually wonder how many came voluntarily and how many were,vehem, coersed? [Previous page](https://tw.forumosa.com/t/coronavirus-taiwan-2021/200866.md?page=3) [Next page](https://tw.forumosa.com/t/coronavirus-taiwan-2021/200866.md?page=5)