Canada casting doubts on anti body tests
COVID-19 antibody tests that deliver a result on the spot are unreliable enough that they should stop being used immediately, according to new Canadian-led research. The research, which was published Wednesday in The BMJ, involved a review of all known studies about the effectiveness of the antibody tests.
Finding dependable information was not easy. The researchers ended up with 40 studies to look over, 70 per cent of which came from China. Most of the studies were found to have been designed in a way that could create a bias in the results, and about half had not been peer-reviewed.
Still, the researchers say the studies were enough for them to reach one clear conclusion: there are "major weaknesses" in the existing evidence supporting the use of blood tests that do not process their samples in laboratory settings. "The evidence does not support the continued use of existing point-of-care serological tests for COVID-19," they wrote.
The new research pours even more cold water on the idea [immunity passports], finding that the serological tests have relatively high error rates. These errors can take the form of false positives, where the disease is said to be found in someone who does not have it, or false negatives, where an infected person's antibodies do not show up in the results.
The researchers found that the studied serological tests fared relatively well when it came to avoiding false positives, with this happening between 0.3 per cent and 3.4 per cent of the time. False negatives were a much bigger problem, with some tests failing to detect COVID-19 antibodies in up to 34 per cent of all those tested who had been infected.
The tests that presented the most false negatives were those of the lateral flow immunoassay (LFIA) variety – the type being considered for use in immunity passports because its lack of a need for lab processing makes it quicker and cheaper than the alternatives. In the U.S., the Centers for Disease Control and Prevention have warned that antibody tests can deliver false results up to 50 per cent of the time.
According to the researchers, their findings suggest that if LFIA tests are given to 100 people who have had COVID-19 and 900 who have not, 34 of those with the antibodies will be wrongly told they do not have them, and 31 of those without will be wrongly told they do.
Just get rid of air crafts ugh
On Wednesday, Nova Scotia Health Authority advised of potential exposure on WestJet flight WS 248 on Friday from Toronto to Halifax. The flight departed Toronto at 10 a.m. and landed in Halifax at 1:04 p.m. NSHA notes while anyone on the flight could have been exposed, based on public health’s investigation to date, passengers in rows 16-21 who were seated in seats A-C are more likely to have had close contact. Passengers in these seats are asked to call 811 for advice.
Erm, don't they know who was on the flight? Is this the level of 'contact tracing' that's going to stop the spread??? wtf.
Now is the time to start building high speed rail lines. Much easier to social distance (add more cars), plenty room for air filters or simply leave the windows open.
Oh and happy Canada day! I spend mine cycling. It was actually a bit more quiet on the trails (36c full sun today) however the river was crazy. I have never seen so many people floating down on whatever they could find. It might be a bit safer for covid19 but I've seen a lot of very red people lol. Sun burned all over. Every access point to the river was packed with cars. Rafts tied together floating down in groups up to 20 people. Tons of rental canoes and kayaks as well, people will be transported back in cramped vans :/ Golf courses along my route were busy, as well as the conservation areas. Now hoping the fireworks tonight don't set anything on fire, everything is very dry. Heat warnings are in effect, temperatures will stay above 30c for the next 7 days with very little chance of rain.
My pool reached 86F / 30c today...