08/05/2020 - 19:30
A little shock; the eyes that appear above the chinstrap and denote surprise. There is no time to process whether it was pain or not. Maybe it felt like a pinch on the index finger. They are milliseconds and the sample is already done. A young neighbor from the Montecastro neighborhood was one of the volunteers who underwent the Seroprevalence Study . That drop of blood they took is sent to the Gutierrez Hospital and in a few days it will reveal whether or not this neighbor contracted coronavirus.
The study aims to measure the percentage of antibodies in the City's population. Determine how many people were infected and did not notice it, either because they did not have symptoms, or had them mildly, and so they did not resort to the health system to do the swab.
The survey is a project articulated between the General Directorate of Statistics and Census, dependent on the Buenos Aires Ministry of Finance and Finance, and the City Ministry of Health. It was launched on July 22 and should be completed by Friday. By then, 2,000 residents will have been tested .
The City Government personnel visit the residents of the Montecastro neighborhood selected to participate in the study. Photo: Juano Tesone
On a peaceful, almost springtime midday, the only movement in Montecastro is noticeable on Alvarez Jonte Avenue, the neighborhood's commercial hub. In the surrounding streets, you hardly hear any noise and you don't see the comings and goings of cars or people. The pollster and nurse representing the City will only knock on the door of the neighbor who has previously given their consent to perform this seroprevalence test. So in some homes they are already waiting for them.
In mid-July, the Buenos Aires Government selected potential volunteers in all neighborhoods and from all social levels, to participate in the study. "It is a tremendously asymmetric disease. In towns and settlements you can have up to 50% of infections among neighbors, as happens in Villa 31. And in residential buildings where the conditions of isolation and ventilation are ideal, there can be up to ten times fewer infections. The challenge is to capture this heterogeneity to give an overview of the population reality of the City, " Daniel Ferrante, Undersecretary for Health Planning and Network Management , explained to Clarín .
Neighbors selected to participate in the seroprevalence study were notified by letter. Photo: Juano Tesone
A letter was sent to these 2,000 selected residents . At first, this created confusion. An audio that circulated in the WhatsApp chats warned that it was a trick to enter the houses to steal. Even Fernán Quirós, the Buenos Aires Minister of Health, had to go out to explain that it was not a false news.
Although the recommendation is to allow City staff to enter the home, it is also not mandatory. The complete process requires less than 15 minutes . First they interview the neighbor to ask him the age, with whom he lives, his work situation and if he has previous illnesses or risk factors, among other issues. Then they take your blood sample.
The process of taking the sample and taking the survey takes less than 15 minutes. It is not essential that Buenos Aires government personnel access the volunteer's home. Photo: Juano Tesone
The person doing the survey has an electronic support that allows him to collect the information and share it with the Statistics and Census Directorate at the time. And each sample is linked to the survey through a QR code. Once the day ends, all samples are sent to the Gutierrez Hospital, where they are processed. It takes between two and three days to know the result . The circuit is closed when the neighbors are informed about the test result. Those who test positive are offered a PCR test (swab), which is also voluntary.
The sample is taken with a finger prick. Photo: Juano Tesone
Does the studio represent all the residents of the City?
"It is a sample that allows us to draw conclusions for the three million residents. They are probabilistic works. The ideal would be to carry out two other similar samples, with another 2,000 different neighbors. This type of survey is like photos of the moment that tell us what is happening. with the coronavirus in the City, "explained José Donati, director of Statistics and Censuses.
On the website of this body there is a list of the interviewers, with name, surname and photo. You can also verify the information through 147. Or on the telephone numbers of the Directorate, 4032-9145 / 9147/9101.
The results of the antibody test are two or three days later. Photo: Juano Tesone
Having this information is vital, because it has implications for public policies. The Villa 31 case highlighted the need to know how this virus evolves. In the Retiro neighborhood settlement, it was verified that 53% of the population generated antibodies to Covid-19.
In the City it is presumed that the number is less. It is estimated that for each documented case, with positive swab, there are between 8 and 10 people who were infected without realizing it . According to official figures, as of Tuesday there were 64,234 accumulated positive cases (residents); If this number is multiplied by 9, it is estimated that there could be almost 580 thousand residents through whom the virus passed.
According to what happened in other cities in the world, the contagion curve began to decrease when between 12% and 20% of the population suffered from the infection. According to Health officials, Buenos Aires is currently experiencing a high but stabilized number of infections.