"...Ravindran shared that Malaysia has been using antigen-based RTKs since May 2020 as a screening tool. It has a short 30-minute turnaround time and can be done in the clinic where the swab was taken, provided the necessary tools are present. It is thus cheaper. However, an RTK-Ag is less accurate than the RT-PCR. Its lower sensitivity (85.5 percent) means there is more chance of false-negative results. For this reason, an RTK-Ag is not typically used for hospital admission. Patients usually need to take an RT-PCR test for confirmation if they have a positive RTK result..."
"...It can be observed that at Ct = 25, up to 70% of patients remain positive in culture and that at Ct = 30 this value drops to 20%. At Ct = 35, the value we used to report a positive result for PCR, <3% of cultures are positive. ...;" Rujukan Mahkamah Rayuan, KEPUTUSAN MAHKAMAH "...If a person has a positive PCR test at a cycle threshold of 35 or higher...the chances of a person being infected are less than 3%. The probability of the person receiving a false positive is 97% or higher”...."
Real-time reverse-transcription polymerase chain reaction
All assays used the same conditions. Primer and probe sequences, as well as optimized concentrations are shown in Table 1. A 25-μl reaction was set up containing 5 μl of RNA, 12.5 μl of 2 X reaction buffer provided with the Superscript III one step RT-PCR system with Platinum Taq Polymerase (Invitrogen; containing 0.4 mM of each deoxyribonucleotide triphosphates (dNTP) and 3.2 mM magnesium sulfate), 1 μl of reverse transcriptase/Taq mixture from the kit, 0.4 μl of a 50 mM magnesium sulfate solution (Invitrogen – not provided with the kit), and 1 μg of nonacetylated bovine serum albumin (Roche). All oligonucleotides were synthesised and provided by Tib-Molbiol, Berlin. Thermal cycling was performed at 55°C for 10 min for reverse transcription, followed by 95°C for 3 min and then 45 cycles of 95°C for 15 s, 58°C for 30 s.
"...We used known SARS- and SARS-related coronaviruses (bat viruses from our own studies as well as literature sources) to generate a non-redundant alignment (excerpts shown in Annex). We designed candidate diagnostic RT-PCR assays before release of the first sequence of the Wuhan virus. Upon sequence release, three assays were selected based on their matching to the Wuhan virus as per inspection of the sequence alignment (Figures 1 and 2)...," Christian Drosten