The sweltering heat of the Venezuelan forest makes no difference to Jose Gregorio, who trembles with a cold chill. "I have pain everywhere, fever," he stammers.

Gregorio has the classic symptoms of malaria, a disease eradicated years ago among his Yukpa indigenous people, but it's back with a vengeance all across crisis-struck Venezuela.

"He had sore joints and then started vomiting, and it's been four or five days since he's eaten anything," says his worried wife Marisol.

Their four-month-old baby babbles beside his father on the bed.

Capuchin friar Nelson Sandoval (R) gives medicine to a Yukpa man suffering from malaria YURI CORTEZ, AFP

"The baby and I also had malaria," says Marisol. "Before, that was not the case here, there was only chikungunya and dengue, malaria came back here last year."

She doesn't bat an eyelid at the mention of either of the other mosquito-borne viruses, whose spread has been fueled by the collapse of Venezuela's health system.

"Here" is El Tucuco, a small village at the foot of the mountains that form the border with Colombia, a three-hour drive from Maracaibo in Venezuela's western Zulia state.

With 3,700 people, El Tucuco is the Yukpas' "capital" and malaria is rapidly making its presence felt here as in the rest of Venezuela -- a country that could once boast of being the first to have eradicated the disease in 1961.

- 'Pandemic' -

There are no official statistics on malaria's reach into El Tucuco, nor on the number of deaths it causes.

But from his consulting room at the Catholic Mission, Dr Carlos Polanco is seeing a developing crisis.

A Yukpa baby waits to be checked by a doctor from the CARITAS organization YURI CORTEZ, AFP

"Out of 10 people who are tested for malaria in the village laboratory, four to five come out with a positive test. This is an alarming figure."

Brother Nelson Sandoval, a Capuchin friar who presides over the mission, adds: "Before entering the order, I already knew this community and I had never seen a case of malaria. Today we are in the middle of a pandemic."

El Tucuco is affected by Plasmodium vivax, the most geographically widespread malarial species. The more lethal Plasmodium falciparum strain is prevalent in the Amazonian regions of southeastern Venezuela.

According to Sandoval and Polanco, the reason for malaria's sudden virulence in El Tucuco is simple: once-regular fumigation missions by the Venezuelan government stopped.

"And as the population of mosquitos increased, cases exploded," said Polanco.

Yukpa men pose with the arrows they use to hunt wild animals YURI CORTEZ, AFP

Added to this is the malnutrition that weakens resistance to the disease, a new phenomenon since the economic crisis took hold at the end of 2015.

"Before, it was possible to vary one's diet, but with inflation the Yukpa cannot afford it," instead making do with what they can grow, like cassava and plantain, according to Polanco.

Rosa, 67, knows all about malnutrition. Lying on the floor of her house, she is battling malaria for the third time. "The doctor weighed me yesterday -- 37 kilograms. I was 83 kilos before."

A report published in British medical journal The Lancet in February warned of an epidemic of malaria and dengue fever as a result of the continuing crisis in Venezuela.

Between 2016 and 2017 alone, the number of malaria cases in the nation jumped 70 per cent.

"The situation is catastrophic," said Dr Huniades Urbina, secretary of the national Academy of Medicine. In 2018, "there were 600,000 cases of malaria and we, the scientific organizations, estimate that in 2019 we could reach a million cases" -- one in every 30 people.

But these figures are only estimates, "because the government conceals the statistics."

-'Nobody answers us'-

The malaria explosion has gone hand in hand with the worsening economic crisis. According to Nicolas Maduro's government, inflation reached a staggering 130,000 percent in 2018 and GDP halved between 2013 and 2018.

A Yukpa girl rests in a hammock while her grandmother lies nearby with fever from malaria YURI CORTEZ, AFP

In the oil-rich state of Zulia, service stations have been dry for more than a month. Electricity blackouts are commonplace and residents flee abroad in their thousands.

Despite a poster of late president Hugo Chavez at the entry to the clinic, there is little sign of government presence in El Tucuco. Dr Luisana Hernandez despairs of ever seeing any state help.

"Every day, everything is deteriorating a bit more," she says, exasperated. Refrigerators intended to keep vaccines cold do not work "because we have no gasoline to run the generator," and both the clinic's broken-down ambulances are gathering rust in the garden.

"We've knocked on every door. But nobody answers us," said Hernandez.

Blood tests of Yukpa people suspected of having malaria are stacked in an improvised laboratory YURI CORTEZ, AFP

Without fuel to bring drugs from the city, without resources to prevent illnesses, eradicating malaria in an almost impossible task.

Brother Nelson does what he can, with help from the Catholic charity Caritas and the Pan American Health Organization. His mission distributes the antimalarial drugs chloroquine and primaquine to sick Yukpa people.

Maria Jose Romero, 22, was able to benefit from treatment. "Repeated seizures are due to the fact that many people cannot follow the treatment," for lack of drugs, she said.

Romero now lives across the border in Colombia, having fled Venezuela. She is visiting El Tucuco to see her family. Soon she will return to the other side of the mountain, on foot.

"It's three days' walk," she says.