[ad_1]
How to detect the many people who do not have Covid-19 symptoms or who have not yet developed them? Since last spring, health and political authorities around the world have been working on this puzzle, with no miraculous solution emerging.
In recent weeks, the popular strategy is called mass screening. Recently implemented on the scale of a city, such as Liverpool in England, a region or even a country, such as Slovakia or Austria, this method consists of testing in large quantities and regularly. Goal: Quickly isolate as many silent cases as possible. As a reminder, asymptomatic agents have never had such a powerful impact in the spread of a coronavirus.
In France, the idea of national screening is not on the agenda at all. Lack of perspective on attempts made abroad, “very complex operational logistics” … The Scientific Council called for caution in a note sent in mid-November to the authorities in mid-November and published on Monday.
However, an important clarification, government advisers – in passing very strict on the “relative failure” of isolating people who tested positive – advise to do “experiments” at the local level. These “could be carried out BEFORE the release of confinement n ° 2 in some metropolises”. In other words, by mid-January. Contacted by us, the Ministry of Health confirms “work” on this hypothesis, but refuses to comment on any agenda.
The key to escaping further imprisonment?
Not surprisingly, the scientific council cites two geographic routes: the Auvergne-Rhône-Alpes and Hauts-de-France regions. While several researchers campaigned for several weeks for Lille and Roubaix to act as guinea pigs for the government, the Auvergne-Rhône-Alpes region had already announced that it would test its citizens from December 16 to 23 in order to protect its citizens. “seniors” during the Christmas holidays.
A thousand sites throughout the region, buses distributed in rural areas, 10,000 people mobilized… On the initiative of this volunteer project, LR President Laurent Wauquiez aims between two and four million tests.
Catherine Hill, former head of the biostatistics and epidemiology department at the Gustave-Roussy Institute in Villejuif (Val-de-Marne), welcomes the fact that experiments are being launched in the region. This is the key, in her opinion, to escape a third wave and a new confinement, as well as barrier gestures and some movement restrictions.
“Today the cases identified are just the tip of the iceberg, the epidemiologist deplores. It takes nine to ten days to tell someone if they are contaminated and contaminated. It’s too long. Suddenly we cannot follow the transmission chains and isolate ourselves over time ”. As a reminder, we are especially contagious in the early days of the disease.
“We are unable to do this on a national scale”
If Catherine Hill’s observation is rather unanimous within the scientific community, the same cannot be said of her initial proposal: to test the 67 million French people every ten days, at least until the arrival of ‘an effective vaccine . “We can’t do this nationally,” says epidemiologist Carole Dufouil, director of research at Inserm. More nuanced on the prospect of a trial in a “well-organized city with efficient laboratories”, she doubts the country’s material and organizational capabilities.
VIDEO. Covid-19: wastewater analysis could predict a third wave of the virus
Lionel Barrand, president of the national union of young medical biologists, also considers this project impossible. And this, even at the city level. “I believe that some do not realize the technical means this represents. Massive testing comes with a crazy reorganization and a huge cost. We should give up all our other abilities, especially in chemotherapy. Not to mention that we are already one of the countries that test the most, “he says.
This biologist also doubts the reliability of the antigen tests, which are at the heart of the system abroad, and should also be found in Auvergne-Rhône-Alpes. The latter are faster than PCR, but one in two asymptomatic ones may be missing. Finally, Lionel Barrand wonders about the real usefulness of saliva tests. “OK, we will have simplified the process with the sputum part, it will be more pleasant for the people tested, but that does not solve the problem of the underlying analysis. We don’t have enough machines to read the results ”.
To all these logistical arguments, Catherine Hill responds “political will”. “We have the means! She proclaims, protesting in passing against the “undocumented” refusal of the High Health Authority (HAS) to use saliva tests in asymptomatic cases or to use the disputed method of “group testing”. “
Slovakia, Liverpool … efficiency that remains to be demonstrated
These different bell sounds do not facilitate the work of the authorities. Especially as abroad, for the moment it is difficult to decide on the effectiveness of this strategy. Slovakian or British authorities could congratulate themselves and promise to re-launch the device in December, the results are unclear. The decline observed there is no more significant than in other regions which have “satisfied” themselves with partial or total reconciliation measures. Once again a sign that there is no miracle cure.
These experiences have also raised another difficulty, already highlighted in the field of vaccines: the question of the participation of the population in these campaigns. Especially among the most precarious. In Slovakia, the threat of quarantine was raised to subdue the refractory, which resulted in a very high participation rate (between 80% and 90%). “In Liverpool, we are starting to have a lot of difficulties, also warns Carole Dufouil, epidemiologist at Inserm. People don’t come back for testing, and there are significant socio-economic differences between those who do. “
Sections of the population difficult to convince
In some of Liverpool’s poorest communities, only 4% of the population took part in the test, according to a BBC analysis. “How do you get people to do the right thing if they are struggling to make ends meet and fear losing their income?” Paying £ 500 in solitary confinement is often not enough to allay their concerns, ”summarizes Annemarie Naylor, director of policy and strategy at the charity Future Care Capital, to the British media.
The scientific council also points the finger at the risk of “an exhaustion effect on the various actors and the population” in the face of “the need to repeat the mass screening every 15 days”.
However, these uncertainties have not deterred Boris Johnson. The British Prime Minister has announced that a “six-week test wave” will also be offered in Manchester, Leeds, Newcastle, Birmingham and Bristol starting Wednesday 2 December, the date of the partial withdrawal of the complaint. Or a project that is now targeting 23 million citizens.
There is no doubt that the French authorities will be keeping an eye on this extremely expensive bet. To better apply it when the incidence rate has dropped to a very low level? This is more or less the method adopted by the city of Wuhan, the cradle of the epidemic, after the first confinement. For an apparently radical result.
Source link
