Irene Hartmann
06/04/2021 6:01 AM
Clarín.com
Society
Updated 06/04/2021 6:01 AM
The Government outlined this week that in July it would begin to immunize those over 18 without risk factors: there are 15 million people.
As the company is large and resources are not abundant, some researchers propose an
alternative plan
: distinguish those who already have some degree of immunity for
having had
coronavirus and administer a single dose, based on the fact that different investigations ensure that in those cases
the reinforcement it does not represent an improvement
in protection against SARS-CoV-2.
In public health jargon, the strategy of separating people according to whether or not they have antibodies against the pathogen being fought is called “
clean vaccination
”.
Although months ago no one doubted that it was urgent to vaccinate the largest possible population against Covid ("
dirty vaccination
"), there are not a few researchers who suggest
taking advantage of the immunological advantage
of the large segment of Covid recovered.
This is expressly stated in a statement, entitled "
SARS-CoV-2 vaccines for all but a single dose for COVID-19 survivor
", published on April 30 in the journal
EbioMedicine
.
It is signed by seven microbiologists, physicians and epidemiologists with expertise in immunization, from universities in the United States, Italy and the United Kingdom.
They almost beg the authorities to listen to the suggestion outlined in the letter's title: "
SARS vaccines for all, but single dose for Covid survivors
."
In the middle of the street, a swab test to detect the coronavirus.
/ EFE
What they suggest is that countries where the Covid does not give truce and vaccines arrive slowly (Argentina would be an example par excellence) could be
wasting doses
.
To avoid waste, you should ideally pay attention to the latest research that ensures that ...
1) those who had Covid develop some type of immunity against SARS (humoral or cellular. We will return to this point),
b) by being vaccinated with a dose,
those recovered from Covid achieve
greater protection against reinfection
than the "virgins" or "naive" (those who did not have coronavirus) who receive the complete scheme,
and, d) upon receiving dose 2, those recovered from Covid did not improve the protection they had.
So with one dose they
hit their "immune ceiling
.
"
Does the Government contemplate "clean vaccination"?
The discussion
At the end of this note,
Clarín
had not been able to obtain a response from the National Ministry of Health.
However, the issue was dealt with in the
National Immunization Commission
(CoNaIn), the technical body that makes recommendations on these matters to the national authorities.
Anyone who has gotten into the scientific scene "Covid" will know that for months there was "pica" between the authorities of the ministries of Health and Science and Technology.
The watershed by the political rift also exists within the groups of doctors and scientists.
Jorge Geffner
is one of the exceptions.
In addition to directing the Department of Microbiology at the UBA School of Medicine, being a specialist in Immunology and a Senior Researcher for Conicet at INBIRS, he is one of the scientists who today supports
rethinking the national vaccination strategy
.
And
he proposed it to the CoNaIn
.
Vaccination against Covid in the La Rural property for people over 65 years of age.
Photo Juano Tesone
A parenthesis.
The vaccination strategy that is being carried out today in Argentina “has the sole objective of reducing mortality from Covid and reducing the hospital burden.
Deciding to block the circulation of the virus
would require
modifying that objective,
"said
Ricardo Ruttimann
, infectologist at the Centro de Estudios Infectológicos Foundation (Funcei) and CoNaIn.
Rüttimann recalled that, for example, “in the annual flu campaign, primary school children are not vaccinated, who are the most contagious.
At the public health level,
there is no proposal to block circulation
.
It would be necessary to see if this is decided with Covid ”.
The chief of staff of the Ministry of Health, Sonia Tarragona, issued this week -in an interview with
Futurock-
a certainty in that direction: the idea is, in July, to start vaccinating everyone.
But how could this objective be addressed and resources optimized by doing clean vaccination?
Let's go back to Geffner.
“The logistics of testing each person for antibodies before giving the vaccination turn could be a bit complicated.
I am not the one to comment on this, although I know that it is not particularly expensive to do so.
But what would be more feasible is to
take all SISA positive Covid and not prioritize them to receive the second dose,
"he specified.
The reasoning starts from that “if one had an immense quantity of vaccines, one could vaccinate with the complete scheme to all.
But in a context of lack, this could be a logical strategy, as well as implementable. "
Before the CoNaIn
"I raised this with the CoNaIn about a month and a half ago, suggesting that I endorsed the strategy," Geffner said, confident in the course of his speech.
However, Rüttimann clarified that, in his understanding, "
it is not in the minutes of the CoNaIn
."
The FUNCEI doctor explained that vaccinating some with one dose and others with two seems to him to be an
understandable but questionable
strategy
"from a programmatic point of view."
On the one hand, he was confident that a massive arrival of doses will be generated in the second half of the year.
Also, he said, “doing a pre-antibody determination to divide who gets a dose or two could be very tricky.
Possibly they end up missing many opportunities to vaccinate: people get tested and then maybe they don't come back.
The coverage would be complicated
”.
The Intensive Care Unit of Cemic.
Photo: Luciano Thieberger.
Finally, he spoke of an additional difficulty: How to know that the Covid survivor really has antibodies?
At this point it is central to remember that human immunity has several fronts. One is
humoral immunity
, which circulates in the blood and is mediated by antibodies (B lymphocytes). Another is
cellular immunity
, a kind of "memory" mediated by T lymphocytes, which microbiologists particularly appreciate because, they affirm, beyond As long as there are no antibodies in sight, this other protection is present "on the court."
The same holds (with solid hard data) a study published on May 27 in the
Journal of Infection
, by English experts from the St. George's University Hospitals NHS Foundation Trust.
The title suffices to describe the report: "
Previous Covid-19 protects against reinfection, even in the absence of detectable antibodies
."
However, Rüttimann was skeptical that a correlate between vaccine efficacy and antibody protection would be lacking: “There are no studies that have modeled this.
There is no serological correlate of protection in terms of antibodies
.
We have them for hepatitis or meningococcus, but not for Covid ”.
“It would be a step forward to know
how many antibody titers
are required to be covered.
It would be a great saving in every sense and it would not be necessary to carry out a study in 4,000 people, expose a placebo group, which is ethically questionable, if one had a more complete knowledge of Covid, "he said.
However, Geffner does not hesitate: it is clear to him that
the immunity of the recovered exists and could even be robust
.
It requires digging in and investigating.
But, he concluded, "what is certain is that in those previously infected, the protection with one dose will not last less than the immunity of the uninfected who received the complete scheme."
$
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