It is becoming more and more evident that climate change is changing our lives.

But now, a team from the University of Hawaii (United States) has published a study that they claim affects more than 200 diseases.

The study, published this August in the scientific journal Nature, His initial motivation was to find out if climate change is affecting the emergence and spread of covid-19, but it has been expanded and expanded. They surpassed the data with more than 70,000 scientific papers and their incidence in more than 200 diseases.

Colombian Camilo Mora, associate professor in the Department of Geography and Environment at the University of Hawaii, led this study of how up to 200 diseases are affected by climate change.

“Climate change has complicated 58% of all human diseases,” says Mora. “Many diseases that are already out there, but you can make them worse.”

He explains this with an example: “I can feel strong, but suddenly Mike Tyson comes along. I can stand it, but it will beat me. But if 3 more people like him get into the same scenario, I can’t survive.

“The vulnerability we have with this is strong,” he adds.

In the investigation, the authors state that they found 3,213 empirical examples of climatic hazards in pathogenic diseases.

Among the main phenomena caused by climate change, they noted four that affect more diseases: Global warming, increased precipitation (122), flood (121) and drought (81) affecting 160 different diseases.

They found more than 1,000 unique ways that “climate threats through different types of transmission lead to cases of pathogenic disease”. These are grouped into four general processes. and how the pathogen behaves (what infects us in one way or another) and who, the people, is infected.

1. Approach of pathogens to humans

This means: geographic shift of species due to climate change.

The area they normally live in changes due to something related to climate change such as increased rainfall, drought or melting snow fields, and animals and all the pathogens they bring with them are displaced accordingly. .

For example, explains Mora, bats in the middle of the forest that live there with their pathogens. “For example, as a result of a fire, the bat has to move, approaching us and all its pathogens with it.”

“Their habitats are affected, we throw the farm to the animals,” he says.

and there increases the likelihood of contact between the two and therefore, the spread of any disease.

2. Proximity of humans to pathogens

There have been increased meteorological events with climate change, and this has led to climate change. displacement of people, both temporarily and permanently to places where pathogens that cause various diseases are concentrated.

One case is an increase in hurricanes or flood. “You have to go around (in the water, in the middle of a flood) and it’s full of bacteria and viruses. You get pathogen,” says Mora.

Thus, the contact between humans and pathogens increases and thus the probability of having related diseases increases.

The drought also caused people to move.

“For example, in Africa, people have to migrate to where there is water. movement transport animals and their pathogens with them and everyone gathers where there is water».

And again, this increases the likelihood of getting sick from increased contact with pathogens.

3. Climate change is making some diseases worse

In some places, as climatic conditions change, organisms and pathogens either die or adapt. By natural selection, the fittest survive. And it has a frequency of occurrence in diseases.

For example, Mora explains, fire as a fighting mechanism against certain diseases and “this creates conditions that pathogens don’t like”.

But as a result of this heat waves, pathogens tolerate higher temperatures.

“If there is a heat wave of 40 or 42 degrees Celsius, it will kill certain pathogens, but those that survive are capable of withstanding it, a temperature higher than normal human fever. So the pathogen already has the ability to neutralize your natural defenses,” he explains.

This same increase in temperature causes In some species, it accelerates the reproductive cycle.

It also happens in some areas with increased rainy seasons and, where appropriate, by mosquitoes, important vectors of diseases such as chikungunya, yellow fever or dengue fever.

“If the optimal conditions for mosquito breeding are prolonged, say, for two months, there will be more opportunity for them to breed,” he says.

4. Climate change is making us weaker and with worse defenses

This happens through several mechanisms.

has something to do with infrastructure and access. For example, “in the event of a hurricane or flood, infrastructure collapse means we don’t have access to healthcare.”

But at the same time It affects us on a bodily level.

To name just one of them, such changes are a cortisol disorder, Activated in the face of danger, the hormone, in turn, activates the “defense” or “flight” mechanism.

“This affects our immune system, and if you get infected, your ability to fight is reduced,” says Mora.

The most “beneficial”

diseases ranging from from diarrhea to cardiovascular diseases, encephalitis or dermatitisThere are some main causes: viruses and bacteria, “the ones that survive the most,” explains Mora.

Transmission has mainly been through water, air, direct contact or food consumption.

“We analyze the impact of climate change on each disease, but not its magnitude and how it spreads. Because it already depends on many conditions, such as the culture of the country, socioeconomic conditions or laws and their appreciation, which is difficult to calculate,” says Mora.

But he highlights measuring how climate change “removes responsibility from the real culprit”.

“You don’t go to the origin and you should look at which diseases can be prevented from the beginning”, point.

Regarding the diseases included in the study, he says he normally pays attention to the contagious ones, but like the others. allergies—effects, one of the most common being pollen allergy—, respiratory diseases or conjunctivitis aggravated by climate change and we must pay attention to it.

It’s “difficult to look for hope”, although the study shows that some diseases (a little over 60) do improve in some cases.

Mora admits from her home in Valle del Cauca: “It’s so frightening, the amount of suffering we saw in our article.”

He points out that what he studies are cases that already exist but still need to be seen. “What will happen to us” if action is not taken, and politicians “stop thinking with their brains and put their hearts into it.”