Chapter 57

"Sour!"

"Indeed, this is sour."

Takeda Shingen and his clan's men and key vassals committed seppuku, leading to the temporary downfall of the Kōshin Takeda family.

The remaining young boys and girls were sent to Azuchi, and Kōki and his troops were stationed at key points in Kai to temporarily govern the region.

During this time, a wealthy farmer from Katsunuma presented Kōki with Kōshu grapes.

Kōki tried them immediately, but as expected, they were grapes from an era before breeding improvements.

To Kōki, they tasted very sour.

"Shōshin, have your taste buds become luxurious, by any chance?"

"The grapes I received from you before were delicious."

The grapes grown in the automated farm in Kanagawa and the vegetable garden within the Shinchi Castle were, of course, improved varieties.

They were large, sweet, and seedless, and Shōshin had enjoyed their taste.

However, some people believed that seedless grapes were inauspicious and refused to eat them.

This belief was also held by a certain number of people regarding citrus fruits.

Shōshin, who did not believe in such superstitions, ate the grapes without any concern.

"Can we process them? Maybe we can ask Kyouko to make jam?"

"Jam? Is that a new food name? What kind of food is it?"

"It's grapes cooked down with sugar, but it's probably better to show you the real thing."

Kōki took a jar of jam from the bottles he had brought.

"Is this jam...?"

Shōshin looked at the strawberry jam with interest.

He must have been curious about whether it was delicious.

Since there was no bread, none of the Shinchi family's vassals had ever tasted jam.

"These are strawberry jams, but the basic method is the same. Alternatively, we could make wine from the grapes?"

"I've heard of that. It's a drink from the Nanban, and I heard that a Nanban missionary presented it to the lord."

"Should I consult Kyouko and ask her to make it?"

"Isn't Kyouko very busy?"

"Come to think of it, you're right..."

Kōki encountered a more troublesome enemy than the rebellion of the former Takeda vassals.

The Shinchi army had advanced into Kai, but they were unexpectedly troubled by an unexpected enemy.

Several soldiers who were playing in the wetlands of the Kofu Basin during their leave complained of itchy skin and later developed fever and diarrhea.

When they were allowed to rest, they recovered, but a local farmer told the army doctor:

"It's probably mud rash... I hope they don't die from swollen bellies."

When the doctor asked for more details, the farmer mentioned that there was a kind of endemic disease that affected many residents living in the low-lying areas of the Kofu Basin.

The disease eventually led to emaciated limbs, yellowing skin, a swollen abdomen due to ascites, and death if not cared for.

"Is there such a disease..."

The doctor, accompanied by his assistants, visited the villages where the sick were located.

Officially, it was a free medical examination to win the hearts of the people.

"This is..."

The doctor confirmed a severely ill patient with a swollen abdomen who could not move, but he judged that he could not do anything with his current skills.

He reported to Kōki, who then wrote a detailed letter to Kyouko, who was a doctor.

Then, she said she would rush to Kai.

"This place is the same as pre-nuclear war Japan. I had forgotten."

As soon as she met Kōki, Kyouko scratched her head and said this.

"Mitchan, I'll explain later, but I'll examine the sick soldiers first."

"Sure, I don't understand anything about it."

Kyouko examined all the soldiers who had developed mud rash, fever, and diarrhea, and began testing their blood and stool.

"I found it!"

Using an electron microscope, Kyouko successfully identified the cause of the disease.

"This is a parasitic disease caused by schistosomes. In Japan, it's called Japanese schistosomiasis, right?"

Kyouko explained this to Kōki when she came to report.

"A parasitic disease..."

"It's quite a troublesome disease."

"I can understand that."

In the future where Kōki and his group came from, schistosomes had already been eradicated from the Earth.

This was due to the success of eradication efforts and the fact that many continents had sunk into the sea due to the nuclear war.

This is why humanity temporarily forgot about the disease, but they would receive a painful backlash during the space exploration era.

On Earth-like planets where colonization had begun, a large number of schistosomes similar to those on Earth were found.

Despite the advanced medical technology of the time, many victims died because doctors initially did not know what the disease was.

Many early colonists also fell victim to unknown viruses and bacteria.

As a result, spaceships began to carry medications and other supplies to deal with these diseases.

Since there were rarely any crew members with medical qualifications like Kyouko, the crew had to fight injuries and illnesses using the ship's facilities.

"These parasites need a host. The infection route is either oral or skin... Since it's mud rash, it's probably skin... I'll investigate in detail."

Kyouko, along with the doctor who initially reported and the medical team, began investigating the infection route.

"Ah, everyone should take this tablet."

Kōki gave a tablet to everyone involved with the Shinchi army.

It was a cultivable insect-killing nanomachine that, when ingested, would multiply in the body for about six months and kill schistosomes, as Kyouko explained.

"I'm glad I asked Maro to mass-produce them. We need to conduct examinations and administer medication to the residents simultaneously..."

While the investigation was ongoing, examinations of the sick, administration of medication to patients, and treatment of severely ill patients were carried out, but it was too late for the severely ill.

The schistosomes that had entered the body had multiplied and laid eggs, accumulating in organs such as the liver, leading to liver failure, cirrhosis, and liver cancer.

In some cases, they had blocked veins, increasing portal blood pressure, eventually causing rupture, or eggs had accumulated in the brain, causing severe brain diseases.

"We need to prioritize treating the early-stage patients and preventing new infections..."

Kōki left this to other doctors and began searching for the host of the schistosomes, fully equipped to avoid infection.

She entered rivers and ponds directly to search for host candidates.

"Lady, the elderly in this area say that children who play in the river and catch fireflies or wagtails will get swollen bellies and die."

"River play... Fireflies... Could it be the food source, Planorbis?"

She immediately caught many Planorbis and investigated, but no schistosomes were found.

She continued to catch and investigate other aquatic organisms, but the answer was not forthcoming.

"It's probably skin infection."

Schistosomes were found in the water of the ponds in the infection-prone areas, so Kyouko told the farmers to avoid entering the water to prevent infection.

"But we can't live without putting our feet in the paddy fields..."

Since they had to grow rice in the paddy fields to survive, it was impossible to prevent the farmers from being infected.

Moreover, it was impossible to immediately eradicate all the schistosomes.

"Lady! We found the host!"

Thanks to the efforts of the doctors, it was determined that the host of the schistosomes was a small snail similar to Planorbis.

However, these snails were abundant in the infected areas.

Eradicating them all was an extremely difficult task.

"Should we use a drug to kill the snails and schistosomes?"

When Kōki stated his opinion to Kyouko, who had come to report,

"The area is too vast. Besides, we can't be involved anymore."

"Come to think of it, that's right."

The Shinchi army was temporarily governing Kai, but it was decided that the area would be given to Toyotomi Hideyoshi, who was currently dealing with the aftermath in northern Shinano, and he was expected to lead his troops to Kai in a few days.

"Schistosomes use snails as hosts, and when people put their hands and feet in the water where these snails live, the parasites enter their bodies and cause disease..."

Shōshin, who had heard Kyouko's report on schistosomiasis, shuddered at the horror of the disease.

"The medicine you have can prevent infection, but its effect lasts only six months. There are too many snails to eradicate... We should leave it to Toyotomi."

"That's a reasonable opinion..."

In a few days, Hideyoshi would arrive, and Kōki would no longer be able to do anything about Kai.

After all, Hideyoshi would become the lord of Kai.

"Should we just sell the medicine?"

To this cold but realistic suggestion from Shōshin, Hideyoshi, who was actually present, cried and clung to Kyouko.

"Oh no... I finally became the lord of a country, please help me. Hanbei, you should also ask Lady Kyouko."

"Lady Kyouko, there might be similar areas to Kai. This could be a practice for when the Shinchi family governs such areas."

The recently highly praised Hideyoshi, who was known for his charm, cried and prostrated himself before Kyouko to ask for help.

This was something a normal samurai could not do, but Kōki and Kyouko found it hard to refuse such a request.

On the other hand, Nakamura Hanbei, who had formally become Hideyoshi's vassal by giving up his fief in Mino, asked Kyouko for help with a reasonable reason: to gain experience in dealing with endemic diseases for the Shinchi family.

"We will do our best to cooperate."

"Thank you!"

Hideyoshi took Kyouko's hand and expressed his gratitude happily.

"So, what's the plan?"

"Let's see..."

First, prevent new infections.

This involved selling the medicine that kills schistosomes in the body, which Hideyoshi would purchase from Kōki at a reduced price.

If taken early, the medicine could quickly kill the schistosomes in the body.

However, if people entered the water again after the medicine's effect wore off, they would be reinfected.

It was Hideyoshi's job to inform the residents of this knowledge.

Next, prevent the residents of the infected areas from directly touching the water in rivers, ponds, and paddy fields.

Unnecessary wetlands would be filled to deprive the snails of their habitat, and the residents would be encouraged to stop growing rice and cultivate grapes, peaches, and mulberries instead.

Lime would be regularly spread in irrigation canals and streams to kill snails, and ducks, which are natural predators of snails, would be raised to make the canals less habitable for snails.

Concrete lining of the canals was also planned to make it harder for snails to live there.

"Complete eradication will likely take a long time. We need to persistently continue the measures."

Even so, the fact that the disease could be treated with medication if caught early brought relief to the residents of the infected areas.

As the new lord of Kai, Hideyoshi implemented policies to reduce paddy fields and increase the production of other crops, gradually reducing the number of schistosomiasis cases.

Especially, the number of patients who had become critically ill and were beyond help had decreased, which was good news.

However, it would take about two centuries to completely eradicate schistosomiasis.

"Even at a low price, we need to stockpile the medication and buy a large amount of the special lime for irrigation and flood control. The money from Kai will cover the cost, but Kōki Shinchi is truly terrifying... We must never make him our enemy."

Nakamura Hanbei reaffirmed the fear of Kōki Shinchi.