Our Hearts. Chapter Four. Symbiosis

Morning in Bata Kolé came like an enemy attack that had long ceased to be expected.

First, silence. Absolute, ringing, pre-dawn silence, when even the cicadas fall quiet, waiting. Then the first ray—sharp, horizontal, plunging into the red clay like a scalpel into flesh. And immediately behind it—heat. Mounting, advancing in mere moments, and total. Within a few dozen minutes, the air erupted in temperature, and the trailer turned into a scorching tin box from which there was no escape.

Leo woke up at eight-ten. He remembered falling onto the cot yesterday fully clothed and in his boots. But now the light blanket was neatly folded back, and his boots stood at the foot of the cot—straight, soles against the wall.

He sat up, rubbing his eyes. Touched his back. There was no blood.

On the nightstand stood a glass. Empty, washed to a shine, and placed upside down on a clean napkin. The white petal inside was gone as well—it seemed the nocturnal guest had returned to reclaim their offering.

Looking at his phone screen, Leo cursed. Sixteen minutes past eight. He had overslept.

Grabbing his backpack, Leo bolted out of the trailer and ran toward the laboratory complex. At the entrance to the green block, he was met by Dr. Lukala Mbuyi—a tall Congolese man in blue surgical scrubs, methodically filling out the biomaterials logbook.

“Good morning, Leo,” Lukala pursed his lips without looking up from the clipboard. “If you’re looking for defenders, there are none. Sarah is already in the lab. And believe me, she logged your absence back at eight-zero-zero.”

Leo slipped through the canvas flap. Inside smelled of talcum, alcohol, ozone, and heated rubber. The mission’s senior epidemiologist, Dr. Huybrechts, was standing at a microscope. Her gray hair was pulled back tightly under a disposable cap, and her back remained as straight as a drill officer’s.

“You’re late, Gonzales,” she said, without raising her head from the eyepieces. Sarah’s voice carried no anger, but rather that icy statement of fact used to announce a diagnosis. “Remy has been working in the isolation unit with Dzuzu for half an hour. We’ve lost precious morning time while the temperature in the isolator still allows one to breathe.”

“I apologize, Sarah. Sleeping effect…” Leo tried to start.

“Apologies do not sterilize instruments, nor do they stop filovirus replication,” Huybrechts cut in, finally turning to him. Her grayish-blue eyes behind her spectacle lenses fixed on him the way a stage holds a slide. “I saw people who were late for shifts in Kikwit in ninety-five. Half of them ended up in mass graves because haste creates breaches in protection. Get dressed. Lukala will inspect the seal.”

The airlock transition into the red zone was located under a double canvas canopy. Here, on a metal table, lay maximum biological protection suits—sealed in transparent vacuum packs, with instructions in four languages.

Leo began to undress. Sweat—instant, slick—immediately coated his chest and back. Stripping off his jeans and shirt, he stood in his underwear on the trampled concrete floor. He took off his massive steel Casio and set it on the edge of the table. Then he unclasped and removed the hoop from his wrist.

The copper slid off his skin, and Leo shuddered involuntarily. He felt cold. No, rather, a sense of sudden physical loss, as though a living suction cup had been removed from his arm. On his wrist remained a distinct, pale band—the mark left by the metal overnight.

Dzuzu Koma, standing by the equipment check station, took a step forward. Her amber pupils fixed on the copper bracelet for a second—literally just a couple of moments. That look was devoid of ordinary curiosity: Dzuzu looked at the amulet with deep, almost professional recognition. But a moment later, her face became inscrutable once more.

“Your suit is over there, Doctor,” she said dryly, extending her hand, on the palm of which lay two brass keys on a wire ring. “Here. Forgive me. Yesterday in the commotion I forgot to give you the spare keys to your trailer. I had them.”

Leo took the keys. The brass was damp from her skin.

“So it was you who left the glass of water?”

“Yes,” Dzuzu nodded, maintaining her birdlike posture. “Last night, when you left for the lab, I noticed that the window was left ajar and insects had gathered inside. I went in to check if everything was all right, and saw that you weren’t drinking any water at all. In our conditions, dehydration sets in imperceptibly.”

“And the flower? The white petal in the water?”

Dzuzu narrowed her eyes slightly, weighing whether to explain.

“Costus. Costus lucanusianus, white costus. It grows only in the most remote ravines of these forests, where the soil never dries out. Local women brew its petals for severe anxiety and fever. It contains alkaloids that act as a mild sedative. Folk medicine, Doctor Gonzales. Sometimes it works no worse than benzodiazepines.”

“Yes, I noticed… Thank you, Dzuzu.”

“Don’t mention it. Now put on your protective gear. Lukala, help him.”

Donning a Tyvek personal protective suit is a strict, almost religious ritual, where the slightest negligence means a death sentence. First came thick medical socks and shoe covers. Then—a snow-white jumpsuit zippered from groin to throat. The fabric rustled unpleasantly, instantly cutting off air access to the body.

Mbuyi approached from behind, deftly pulling the first pair of latex gloves onto Leo, tucking the sleeves of the jumpsuit underneath them, and meticulously sealing the joints with duct tape.

“Hold your arm steady, Leo,” Lukala murmured, deftly wrapping the adhesive tape. “In nine cases out of ten, infection occurs not because of a tear in the fabric, but because some distracted virologist improperly secured a cuff.”

Next came massive rubber boots, and a second pair of thick nitrile gloves over the first. And finally, a 3M respirator mask with a pair of gray boxy P3 filters and a transparent face shield.

As soon as Leo tightened the head straps and checked the seal—inhaling sharply, forcing the mask to suction tight against his cheeks—the outside world receded completely. Sounds turned into a dull, muffled echo. The sole dominant rhythm became his own raspy breathing, resonating inside the plastic helmet.

“Welcome to the white world, Doctor Gonzales,” Lukala said from beneath his mask and lowered the canvas airlock flap with a slapping motion.

In the red zone isolation unit, the air was dense, hot, heavy, saturated with the pungent smell of sodium hypochlorite, which orderlies used to drench the wooden decking.

Remy was already standing by the first cot. In his white protective suit, bathed in halogen light, he looked like a huge statue carved from fog.

“Finally, Leo,” Remy muttered dully through his mask speaker. “I was starting to think you decided to take the day off. Take a close look at our guy.”

“Mbul Benga,” Mbuyi said without looking at the patient. His voice from beneath the mask sounded muffled, as if from behind a wall. “Twenty-one years old. Artisanal miner. Worked at an informal plot a kilometer and a half from the IC Waze mine. Helped carry the body of the first deceased.”

Thin, wiry, with a sunken chest and dry dark skin. On his neck, shoulders, and ribcage, spots stood out clearly—not classic hemorrhagic rash, but a fine, dark petechial network resembling wild berry juice spilled beneath the skin. He was conscious. His large, inflamed eyes with dilated pupils tracked every movement of the white figures. In that gaze there was no panic whatsoever—only a deep, detached attention.

Leo pulled out an electronic stethoscope and pressed the sensor to the miner’s chest, routing the audio stream to his helmet’s internal earpiece.

What he heard made him freeze.

“Remy… Dzuzu… Do you hear this?”

His heart was beating at sixty-two beats per minute. For a person with a fever near forty degrees Celsius, with a febrile syndrome and signs of vascular damage, this was a physiological absurdity. Tachycardia should have been tearing his chest apart, forcing the myocardium to pound at a rate of one hundred and forty. Yet his pulse remained calm and steady.

But that wasn’t the main thing.

Instead of the familiar pure tone, Leo heard a low, visceral, heavily pulsating hum. The aorta was functioning with incredible, hypertrophied force. On the miner’s neck, right above the collarbone, a visible pulsation was apparent—the skin stretched and dipped in a rhythm that felt too massive for a human body.

“I’ve been listening to him since morning,” Remy uttered, leaning closer. “This isn’t ordinary regurgitation. Listen to the base. Don’t you get the feeling that there are… two sources of rhythm?”

“Precisely,” confirmed Dzuzu, standing with a tablet at the head of the bed. “Yesterday on portable ultrasound I didn’t find any anatomical valve rupture. The aortic wall is thickened, but retains integrity. Yet the heart pumps blood as if an additional hydraulic pump were installed inside it. It isn’t succumbing to destruction—it has… adapted?”

Leo moved the sensor lower, to the epigastrium. The low-frequency noise echoed in his own ear canal, and for a second Leo felt a strange, sickening longing: his own heart inside his suit tried to falter, adjusting to this other, alien rhythm.

“All right,” Leo sighed heavily. “Let’s go to the reefer. We need to compare this to the dead.”

The second block of the red zone—the autopsy morgue—was located in a separate tent equipped with two refrigerated containers. The cold burst outward in thick white steam, clouding his face shield.

On steel tables lay two bodies: the white man found in the forest, and the local hunter Kasongo Mpala.

The difference between the living miner and these two was catastrophic in nature.

“Here the virus acted as a classic detonator,” Remy said, helping Leo secure the margin of the autopsy incision. “Total necrosis. Look at the liver.”

Leo made a deep incision. The scalpel entered the tissues with a soft, wet crunch. The white man’s liver was twice its normal size, had lost all structure, and resembled a boiled, decaying mass with a nutmeg pattern on cross-section. The abdominal cavity was filled with a liter and a half of black, uncoagulated blood, resembling used motor oil. The vessels had collapsed, the endothelium completely destroyed.

But when Leo reached the chest cavity and opened the pericardium, he stopped.

“Sarah needs to see this,” Remy whispered, his voice trembling.

The aorta of the deceased white man was dilated along its entire length—from root to arch—by roughly twenty percent. The vessel walls looked impossibly dense, edematous, and on their inner surface, small nodules protruded, resembling pearlescent grains of rice. There were no traces of ordinary calcification or atherosclerosis in them. The tissue of the wall had a strange, pearly-purple hue reminiscent of a seashell.

Leo carefully excised three fragments: for formalin, for freezing, and for PCR analysis.

“Same thing with the hunter?” he asked.

“Carbon copy,” Remy replied, nodding toward the second body. “Fulminant death in forty-eight hours, destroyed viscera, black blood… and a remodeled, hypertrophied aorta with nodules.”

By three in the afternoon, the entire medical team had gathered in the lab’s green block. The air hummed with the sound of the portable DNA-MinION sequencer, reeking of bleach and creosote. Having shed their protective suits, the doctors sat around the work table in sweat-drenched surgical scrubs.

Huybrechts studied the fresh printout of the genomic analysis. Her finger with its short-trimmed nail traced the nucleotide sequence graph.

“It is a filovirus, without a shadow of a doubt,” she said. Sarah’s voice was dry, but underlying it was a tension Leo had never noticed in her before. “Look at the protein scaffold structure. RNA, glycoprotein envelope—everything points to the Filoviridae family. Ebola.”

“But look at the variability!” Remy nervously ruffled his sweaty hair. “You ran the samples from the first corpse through all known databases. Mayinga, Kikwit, Sudan, Taï Forest, Bombali… A genomic mismatch of thirteen percent!”

“Thirteen percent is a chasm,” Lukala Mbuyi piped up, leaning against the edge of the table. “The difference between a human and a chimpanzee is just over one percent. Thirteen percent for a filovirus means we are not dealing with a new mutation or a seasonal strain. This is an entirely separate lineage. Or… a very ancient progenitor that evolved in isolation from all the rest.”

“All right,” Leo brought up the biochemistry and PCR data of the living patient, the miner, on the monitor screen. “Now explain this to me. These are Mbul Benga’s lab results. Viral load is present in his blood, but the titer is twenty times lower than in the corpses. The virus isn’t destroying his liver. Kidney panels are normal. Coagulation profile is slightly shifted, but not fatal. At the same time, the aorta is dilated, and the echocardiogram shows an anomalous second rhythm.”

Sarah slowly raised her eyes to Leo.

“What do you think, Gonzales?”

“Ebola is a blind and blunt killer,” Leo replied, speaking unhurriedly. “It bursts into the body, burns up the vascular endothelium in three days, kills the host, and dies with it if it fails to transmit further.” He exhaled. “Whereas this strain in a living patient behaves differently. It doesn’t destroy cells. It utilizes them. The virus remodels his cardiovascular system. It forces the aorta to thicken and the heart to pump blood with redoubled force, all while restraining its own tissue lysis.”

“Symbiosis?” Lukala asked quietly.

“Symbiosis,” Leo repeated. “Perhaps. Or adaptive restructuring. The virus doesn’t kill the host; it turns his body into a permanent, durable reservoir.”

“Viruses don’t go around ‘repairing’ organs out of altruism, Leo,” Sarah interrupted sharply. “If a virus fortifies vessel walls and alters cardiac function, it means it requires elevated hemodynamics to fulfill another task. And that task is as yet unknown to us.”

The discussion was cut short by a shout coming from the outer boundary of the camp. The voice belonged to one of the security soldiers.

Sarah, Leo, and Remy stood up instantly.

A crowd had gathered by the yellow plastic tape demarcating the perimeter. Three soldiers with rifles at the ready were holding back a group of local residents.

Out front stood two girls, clearly sisters—fourteen and eleven years old. The older wore a faded blue dress, the younger a pink one, oversized for her frame. Both stood pressed together, staring motionlessly at the ground. Behind them, their parents shifted nervously—a tearful mother and a sullen father with the calloused hands of a peasant.

A bit further away, leaning on a carved cane, stood a local shaman. A tall, withered old man in a threadbare European shirt over a skirt of dry plant fibers. Around his neck hung bones, shells, and dried bird feet. The old man looked at the white doctors with a faded, milky gaze, his lips moving continuously, chanting a silent, rhythmic spell.

Dzuzu Koma was already at the tape, conversing rapidly with the father in Lingala.

“What’s going on?” Sarah asked quickly, approaching the perimeter.

“This morning the girls started bleeding,” Dzuzu turned to her colleagues. “From their nose and gums. Simultaneously. The parents are panicked. The bleeding has stopped now, but look at their eyes.”

Leo stepped closer. The older girl slowly raised her head. Her sclerae were heavily bloodshot, dark red—not from tears or lack of sleep. The capillary network was inflamed and had merged into a solid purple membrane framing dark, surprisingly serene pupils. For the younger girl, the picture was identical.

“Temperature?” Sarah asked sharply.

“Thirty-seven point two for the older, thirty-seven flat for the younger,” Dzuzu replied.

“We need blood samples,” Leo said. “Lukala, bring rapid sampling kits.”

While Lukala Mbuyi and Dzuzu swiftly and skillfully drew blood from the girls’ veins—they didn’t even cry out, only squeezing their mother’s fingers tighter—the sisters’ father spoke hurriedly in French, addressing Leo:

“Doctor… Take them. Put them in the tents. Save them!”

Leo looked at Sarah. She shook her head firmly.

“No,” Leo cut in, turning to the father. “Listen to me carefully. In those white tents are people with a severe, deadly form of infection. Your daughters currently show no severe symptoms. If we place them in isolation, they will guaranteed catch the virus from the sick and die within three days. Is that what you want?”

The father backed away a step, looking at his wife in confusion.

“We will examine them. But then, home, quarantine,” Lukala joined in, handing the father four white medical masks. “Lock the girls in a separate room. No contact with neighbors. No one goes in to see them except you. You enter strictly wearing these masks. Tomorrow morning Dr. Koma will come to your village for an inspection.”

The shaman behind the parents suddenly raised his voice. His muffled muttering gave way to a harsh, guttural chant. The old man raised his cane and pointed it not at the camp, but off toward the hill rising behind the village, where the mines were located.

“What is he saying, Dzuzu?” Remy asked softly.

“He says… that this sickness came not from the trees nor from beasts,” Dzuzu translated deliberately, her eyes fixed on the old man. “He says that the white people dug up a stone that was meant to lie in the earth until the end of time. That this is no sickness. It is… a curse. And the earth will take those it deems its own.”

The shaman turned and, without saying goodbye, tramped away through the brick-colored dust.

The results of the sisters’ blood tests were ready by nine in the evening. Outside, a tropical thunderstorm was commencing: large, sparse drops struck the lab’s canvas roof with a loud clatter.

Sarah, Leo, and Remy leaned over the printout.

Samples from both girls tested positive for filovirus RNA. But the titer levels were so minuscule that the automated analyzer output a rare system flag in the margin: “Below threshold – uncertain significance.”

“It isn’t merely holding back,” whispered Sarah Huybrechts, and for the first time something resembling a suppressed, superstitious fear sounded in her voice. “In the bodies of these children, the virus induces no immune response whatsoever. Neither IgM nor IgG was detected. Their organisms’ immune system simply… doesn’t see it. Or considers it their own tissue.”

“And look at the pulse,” Leo pointed to the bottom line of the printout. “Both girls have a heart rate twelve beats below normal for their age. Just like Benga.”

“The virus has assimilated,” Remy stated, leaning back in his chair. “In adult men with weakened health, it causes a catastrophe or cardiac overload. But in children, it seems to recede into the shadows and alter metabolism.”

“Damn. If you’re right… This is no ordinary outbreak, colleagues,” Sarah concluded quietly, closing her protocol notebook. “We have encountered something that has been brewing here for decades. Everyone go to sleep. Tomorrow will be a difficult day.”

Around eleven in the evening, Leo returned to the anteroom-changing area of the green zone to retrieve his personal belongings. The camp was already plunged into darkness, pierced only by flashes of distant lightning and the dim glow of halogen lanterns.

Leo washed up at the basin, wiped his neck with a stiff paper towel, and opened his metal locker.

His Casio watch lay on the wooden shelf. Next to it rested the copper amulet.

Leo reached out and picked up the bracelet.

The metal scorched his fingers.

This wasn’t room temperature. The bracelet was freezing cold. As if a piece of copper had lain in deep freeze at minus twenty for several hours. The cold was piercing, unreal, emanating from the very structure of the metal.

Leo froze, ready to drop the amulet from his hands, but his fingers would not unclasp. As if obeying an unconscious, agonizing impulse, he overcame the resistance, pried open the band by force, and slipped the bracelet onto his right wrist.

It felt as if an icy wave immediately pierced his skin, surging up his forearm to his elbow, shoulder, and down his back. Leo’s pulse spiked sharply, and then beneath the hoop a cool, dull ache flared and instantly subsided. The pale band of skin on his wrist disappeared in an instant—the bracelet fit perfectly, precisely in its former place, as though growing into the body it already considered its own.

He hurried out of the changing room and walked along the rain-soaked path toward his trailer.

The night over the camp was alive, smelling of ozone, damp clay, and rotting leaves. The morgue’s diesel generator hummed behind the tents with a steady, white noise.

And then Leo heard them.

Drums.

But this time the sound was completely different. It had lost yesterday’s terrifying proximity and pressure. The beats sounded far away, muffled and distorted, as if travelling through a mass of water or traversing a multi-kilometer concrete tunnel.

Tum… Tum-tum.

Two beats. Pause. Two beats.

The singing—a solitary, slender female voice holding an endless note—filtered through the veil of rain like a barely audible echo, flickering on the very edge of human hearing. This was not the ritual itself. It was its ghost, its reflection, trapped in the night air of the jungle.

Leo stopped at the door of his trailer.

The copper bracelet on his wrist was gradually losing its coldness, warming up from his skin. But for a fraction of a second, it felt to Leo as though the metal was vibrating in time with the distant beats.

He entered the trailer, locked the door with two turns of the key, and sank onto the cot without turning on the light.

The ceiling of sagging iron hovered over him in the darkness. On the nightstand, the empty glass glinted dimly.

Leo pressed his palm to his chest. And there, in the silence of the enclosed space, he distinctly felt how his own heart—a healthy, well-conditioned heart—suddenly stumbled. Faltered. Missed a beat.

And in the resulting pause, something alien answered within his ribcage.

A quiet, muffled, second beating.

Like the distant echo of a drum.

Chapter Five. Spirals and Lines →
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