The relatively more virulent and deadlier variant of SARS-CoV-2, known as the British (or correctly B 1.1.7), was spreading in various countries, certainly as early as October 2020. Meanwhile, the first mentions of him did not appear until December. Since it was discovered in Great Britain, it was assumed that it was created there.
“By the time we found out about this variant in December, it was probably already around the world. It spread quietly – says prof. Lauren Ancel Meyers, lead author of the study. – We estimate that he arrived in the United States around October 2020, which is two months before the talk was started.
By analyzing data from 15 countries, the researchers sought to determine the probability that British travelers introduced variant B 1.1.7 to their territories between September 22 and December 7, 2020. It turned out that it almost certainly reached all 15 countries by mid-November .
‘These results underscore the importance of laboratory surveillance: rapid and extensive sequencing of virus samples is crucial for the early detection and tracking of new variants of particular concern,’ Meyers said.
With the publication of the results of their study, the Texas group released a tool that public health officials can use to plan SARS-CoV-2 genetic sequencing. It is an online calculator that indicates how many virus samples need to be sequenced to detect new variants when they first appear. For example: if the goal is to detect a new variant by the time it causes 1 in 1,000 of all new COVID-19 cases, you should sequence approximately 3,000. SARS-CoV-2 positive samples weekly.
“Officials are constantly looking for better ways to deal with the unpredictability of this virus and its future variants,” said Dr. Spencer Woody, co-author of the study. – Our new calculator determines how many positive SARS-CoV-2 samples need to be sequenced to ensure a new threat is identified as soon as it begins to spread.
– We created this tool to support federal, state and local health services in creating reliable early warning systems for this and future pandemic threats – adds Prof. Meyers.
The results of the study were published in the journal “Emerging Infectious Diseases”.