It is estimated that in three to four weeks, the wave of dengue will subside.
Likewise, the precision of the date does not alleviate the subjective irritation of the repellent at all times and hearing that acquaintances or relatives are infected.
Some, serious, with scary hemorrhagic pictures.
Given that more than 30 people died and the figure is unprecedented for Argentina, the obvious question is
what does this dengue outbreak have that previous ones have not
?
As a good epidemiological phenomenon, the outbreak is multifactorial, but it forces (like almost everything in Argentina) to look at the Health efforts and the living conditions of the population.
A multicausality that can be organized according to
four aspects
.
In their own way, each adds contagion.
Contagions that, by the way, are represented by an uncertain figure, with its borders.
On the one hand, the new epidemiological bulletin will be scheduled for this Friday night and will offer data, but with a week delay.
On the other, the last bulletin reported more than 28,000 infected, but there are many more.
Taking a
minimum estimate of
asymptomatic , there would be more than 111,000 people with dengue (two weeks ago).
Aedes aegypti mosquito larvae.
Photo: EFE
When does dengue end?
Before going to the four causes and to start with a spoonful of good vibes, let's see when the end of the outbreak is estimated.
Two specialists,
Roberto Debbag
-director of the Latin American Society of Pediatric Infectious Diseases- and
Francisco García Campos
, general director of the Epidemiological Coordination of Salta (the province that this season accounts for a third of the deaths from this virus) agreed that "in three weeks is over."
The one who explained it in depth (and, to be exact, pointed out that he prefers to think in
four weeks
) was
Julián Antman
, an epidemiologist who served as operational manager of Epidemiology for the city of Buenos Aires until March 2022.
“It will puff more in the middle of May than at the beginning of the month, I would say.
It has a linear association to temperature,” she snapped.
May, a key month
You have to understand the staggered logic of the virus to understand why the cold does not resolve the outbreak immediately.
"Rather than thinking about the death of the mosquito due to the cold, the question is to understand that there is an intrinsic period of the disease," he said.
Thus, he said: "If I have dengue today and I am in the viremic phase, I can infect a mosquito that bites me. That mosquito will
intrinsically
require , depending on the temperature, 7 to 12 days to be infective. However, if the temperature is less than 22 degrees average, it will not be able to infect and it will die before.
In other words, while “the mosquitoes that emerged from the water today are probably no longer infective, there are others that bitten 8 days ago and those are: they have at least 20 days left to live, even if it is less than 22
degrees
.
That is why we can think of mid-May as the end date of the intense outbreak."
Now, why is this outbreak worse than the previous ones?
1. Dengue serotypes
It is worth a review, both for the theoretical part of dengue and for past outbreaks.
The more information, the more incentive to care.
It is essential to know that there are four serotypes of dengue and that whoever has had one will generate lifelong antibodies for that type, but will run the risk of suffering a serious condition if infected with a second serotype.
This problem is magnified when one assumes that it could have been asymptomatic dengue.
If you look at the 2016 outbreak, for example, serotype 2 wasn't even on the national map, dominated by 1 (historically most common) and 4.
Around 2017, an imported case of 2 appeared, coming from Brazil.
In 2020, the scenario changed, but only a third of the jurisdictions with dengue registered serotype 2.
Although it is an estimate that illustrates the matter, it is not difficult to deduce that a large part of those susceptible to "second infection" that left the outbreaks of the last decade, contracted serotypes 1 and 4. The least, type 2, which with 1, they now make up the dominant serotypes in almost the entire country.
Antman agreed that the particular presentation of serotypes in each outbreak can indeed have
consequences in subsequent outbreaks
.
And he remarked that having "good information", as he -he opined- "is seen in the Nation and City bulletins, is key".
2. Dengue and poverty
The relationship between socioeconomic conditions and health is very close.
Debbag highlighted it: "This scrapping is a difficult reality because it is not so easy for 40% of the population below the poverty line to do it, neither at home nor in the surroundings of their homes."
On the other hand, not only many homes without a network connection need to store water in containers for their daily lives.
In addition, Debbag pointed out, “the elements of the industry, such as simple soda caps, also promote contagion.
They collect water and that's where the mosquito breeds."
Andrea Uboldi
joins the chat.
She is a pediatrician, infectologist, former Minister of Health of Santa Fe (province among the most affected by the outbreak) and advises the Health Commission of Deputies of that province and is a member of the National Immunization Commission (CoNaIn).
From her gaze, "the scenario is really very complex."
"After the pandemic, life found us with many social and economic problems," he said.
He added that, "beyond the fatigue of health issues, concern for other circumstances dominates, which in many cases also end up covering up what is happening in each neighborhood and in each place in the country."
3. Immune silence
During the Covid pandemic, much was said about the concept of immunological or “immune” silence.
He alluded to the fact that SARS-CoV-2 had displaced other circulating viruses from the so-called “epidemiological niche”.
In the medium term, this would leave us weak when it comes to facing other pathogens with which we usually live.
It would make that relationship difficult.
Debbag opined that some of this has an impact now: “Immune silence throughout Latin America could be generating a higher rate of severity and mortality.
In fact, it is being investigated whether there are genetic changes in arboviral diseases.
It is happening with chikungunya, a virus for which a different genomic variant was seen, and it could be happening with dengue."
But the immunological silence could (metaphorically) have a different meaning: a “silence” or parenthetical space in management, fully committed to the pandemic.
“Why is this outbreak different?
We are coming out of a pandemic.
There were two years in which it was not possible to work on promotion and prevention due to social distancing and the prohibition of entering homes ”, admitted García Campos.
In this sense, “there are tasks to resume.
The most important is the
training
of health personnel "." We were very limited by the pandemic ”, he insisted.
Uboldi agreed with the Salta official: “The Health system is very tired.
The pandemic really had its impact.”
4. Mosquitoes and climate change
The lack of interest in
climate change
is almost total, even when some consequences hit us directly.
More than talking about genomic changes, for Antman it should be noted that "
the mosquito is increasingly resistant to low temperatures
."
García Campos also alluded to this problem: "This year we have gone from a dry season with many sources of fire to another with rain and high temperatures, something that if sustained for several days, helps the development of aedes aegypti
.
"
Uboldi added that "the drought, that is, the lack of water, disorderly urbanization and climate change make it necessary to think about new control mechanisms."
That is, “think of a mosquito that moves indoors.
A change is needed in the conception of the people”.
Along these lines, Antman concluded, we must "change the narrative in addressing the problem: it is not 'fighting' or 'beating' nature; it is learning to live with the mosquito
and
building new ways of understanding what we generate as humanity ".
PS
look too
Why a 76-year-old person died with dengue in the City and the case is not counted
Historical record of deaths from dengue in Argentina: they already reach 32 in eight provinces