In the tent, except for these death row inmates, everyone including Chi Fei and other soldiers wore masks.

On the table in front of Chi Fei, there was a small bowl of pus and blood.

This bowl of pus and blood was the pustule pus he had just extracted from the sick cows.

In addition to this bowl of pus and blood, there was a clean white cloth next to it, on which a sharp knife was placed.

He had already washed the knife with water and burned it with fire to make sure it was clean.

Chi Fei stood up and said to all the death row inmates, "Before the experiment, I want to explain the process to you first.

I'm going to use this knife to make a small cut in your arm, and I'm going to drop the pus on your wounds.

After dripping pus, you should never touch the wound and wait for it to heal naturally.

Over the next few days, you may experience fever, rashes, pustules, and other symptoms on your face or body.

If there are no accidents, it should slowly heal after a few days. Did you all hear me clearly? ”

The death row inmates did not say a word, but could only look at each other. At this point, they had no way back but to accept the experiment.

Chi Fei didn't come to do good deeds, since they all had no opinions, then he could officially start experimenting.

He first asked a thirty-something death row inmate in front of the line to sit at the other end of the table, and then he took a knife and gently cut the skin on the inside of the death row inmate's arm, and then cut a small wound of less than a centimeter.

Bright red blood immediately flowed out of the wound, and Chi Fei deliberately waited for the blood to stop when the blood was about to stop, and then used a bamboo skewer to drip the pus from the bowl onto the wound.

After dripping pus, Chi Fei said to the death row inmate, "You just lay your arm flat and let the pus slowly seep into the wound." Remember not to touch the wound and wait for it to heal naturally, understand? ”

"Yes, sir." The death row inmate did so very cooperatively.

Chi Fei said to the two soldiers standing behind him, "You take him to the Jiazi barracks, and the two of you will be responsible for guarding him in the next few days, and report anything immediately." ”

"Yes, sir." After the two soldiers received the order, they quickly took the death row prisoner away.

After Chi Fei helped a death row prisoner to be inoculated, he would put a knife on the fire and burn it for a while to sterilize and disinfect it.

In this way, Chi Fei inoculated the death row inmates one by one in this way.

After each vaccination, the soldiers were asked to take them to separate barracks to avoid cross-contamination and affect the accuracy of the experiment.

When it was the turn of the bookish old man, Chi Fei suddenly heard the other party ask very politely, "My lord, are you practicing the technique of human pox?" ”

Chi Fei looked up at him with some surprise, "Old man, do you also know the technique of human pox?" ”

"The old man once read this method in an ancient book.

It is said that as long as the pox liquid from the body of a person who has a sore is dropped on the wound of an ordinary person, that person can be saved from sores for life.

It's just that the book says that the number of this method is very low, and most of the people who suffer from acne are still infected with scattered sores, so this method has gradually disappeared. ”

Chi Fei said solemnly, "Sir, please rest assured, this is not a human pox technique.

Although it can also cause sores to scatter, it should not be very serious, let alone fatal.

As for the outcome, we'll find out in a few days. ”

The old man also hopes that the adult's method will be effective, so that he can save countless Li people. Please, sir. ”

Chi Fei nodded, and then planted pox liquid on his arm.

When he was about to be escorted away by the soldiers, Chi Fei suddenly asked, "May I ask the old gentleman's surname?" ”

"Under the exemption of your surname Zhang, Zhang Wenxuan."

"Mr. Zhang, please go slowly." Chi Fei arched his hand at him.

Zhang Wenxuan couldn't return the salute because his arms needed to be flat, so he had to nod to him, and then followed the soldiers out of the barracks.

It didn't take long for all the death row inmates to run out of pox fluid.

Chi Fei carefully sealed the small bowl containing the remaining pus with oiled paper, and he kept it for three more experiments on durability.

He would leave the pus in three, five, and seven days for three cycles, and then inoculate the other three batches of death row inmates.

See if the pus will be effective after so many days.

These other three batches of death row prisoners have a total of thirty people, and Chi Fei has already asked Ning Yafeng to find them, and I believe it will not take long to send them over.

The reason why he wanted to do this kind of durability experiment was because the northwest region is vast, and even if the pox liquid just extracted from a sick cow is delivered to a distant area such as a border county as quickly as possible, it will take at least three to five days.

If there is a time limit for the effect of the pox liquid itself, it is useless to send it over.

So he needs to do this durability experiment to see how many days the pox liquid can be valid for.

If it is confirmed that the pox liquid must be fresh to be effective, then these sick cattle can only be taken to the field for on-site inoculation from region to area, which will become quite slow and labor-intensive.

And once these sick cows are cured, the raw materials for the connection are gone, which is what worries and headaches Chi Fei the most.

Therefore, this durability test is a must.

Of course, the premise of everything is that this pox liquid can really make people immune to sores, otherwise it is just a waste of time.

……………………

When the second and third batches of death row inmates were sent over one after another, the first batch of death row inmates who had been vaccinated with cowpox all showed symptoms of scattered sores.

A small number of people develop a fever, but the most obvious symptom for most people is a red rash near the wound.

After two or three days, the rash turned into a blister-like blister.

After that, the herpes ruptured and turned into pustules.

All this is very similar to the symptoms of patients with sores, and many death row inmates who have had acne are scared half to death.

Chi Fei did not ask the doctor to treat them, but he would personally observe their situation twice a day, morning and evening, and told them not to touch the wounds and wait for them to heal naturally.

As for the remaining three groups of death row prisoners, Chi Fei also conducted pox experiments on them in three cycles of three days, five days, and seven days as originally planned, and then locked them alone in the barracks for observation.

On the tenth day, Chi Fei was pleasantly surprised to find that the pustules on the first batch of experimental death row prisoners began to scab over, and there were no other symptoms.

Twenty days later, the scabs of the first group of death row inmates began to peel off, revealing some unsightly scars.

The pustules on the bodies of the second batch of death row inmates have also scabbed over like the first batch of death row inmates, and the situation has all developed in a better direction.

After a month and a half, all the wounds of the condemned prisoners had come out of their scabs, which showed that the pox liquid was effective for seven days.

As for how long it can be put there, Chi Fei is too lazy to experiment any further. Seven days is enough, and any more is a waste of time.

Next, the infection experiment, the most critical and important step of the experiment.

To put it simply, these death row inmates are directly infected with sores to verify whether they have developed immunity.

There are two ways to infect them, one is to give them clothes and utensils to use, and the other is to plant the pus from the pustules of the sore-breaking patients on them like a cowpox.

Compared to the first method, it is obvious that the second method is more accurate and intuitive, so Chi Fei chose the second method.

Since the belongings of the sore-scattering patients, especially the pus, were full of the risk of infection, it would be too risky to bring them to the camp in such a hurry that the plague could break out in the entire camp.

Chi Fei saw that since so many people who had gone through pox were fine, it could be seen that although this cowpox liquid didn't know if it could make people immune to sores, at least it would be fine if it got people.

In order to make the people in the experimental camp the first batch of people who may be immune to smallpox, he discussed with Ning Yafeng and simply let everyone in the camp be vaccinated with cowpox, which can be regarded as an extra layer of protection.

Chi Fei wanted to wait until everyone had been vaccinated with cowpox before considering conducting infection experiments in the camp.

Ning Yafeng has also seen what her brother-in-law wants to do these days. Regarding his brother-in-law's proposal, he agreed without saying a word.

Chi Fei re-extracted some fresh pox fluid from the sick cow and personally inoculated all the soldiers.

Of course, you can't all come together, otherwise there will be no one to keep the camp running.

Therefore, Ning Yafeng divided the soldiers into two groups, the first group came first, and the second group came after the symptoms of this group of soldiers disappeared.

In order to reassure all the soldiers, Ning Yafeng was also the first person to accept the pox in public.

Seeing that Ning Qianhu, who was in charge of leading the army, personally went into battle, the other soldiers who were originally a little nervous relaxed and began to line up for vaccination.

Since Chi Fei is the only one who can do this, he is also the last to be vaccinated.

Looking at the small wound on his arm that had been cut, Chi Fei's heart fluctuated.

He really hopes that this method will work, and success or failure will be made in one fell swoop.

……………………

Two days later, all the people who had received the pox, including Chi Fei, began to have symptoms of scattered sores one after another, the most obvious of which was the appearance of red rashes and herpes on all the wounds.

Chi Fei himself even had a low-grade fever, but Ning Yafeng was very energetic in comparison.

After more than half a month, many soldiers' wounds began to scab off, and Chi Fei was no exception.

After inoculating the remaining group of soldiers, Chi Fei finally decided to conduct the most critical infection experiment.

First of all, he sent the two soldiers who had been vaccinated with cowpox into the Class A quarantine area in Pingnan County, squeezed the pus from the pustule of one of the sore-scattering patients into a small bottle, and then sealed it with oiled paper and brought it back for experiments.

After the two soldiers carefully brought back the pus from the smallpox patients, Chi Fei summoned the first batch of ten death row prisoners to the barracks, and then made a small cut in their arms with a knife, as they had done with cowpox before, and then dripped the pus from the sore-dispersing patients onto the wounds.

The condemned prisoners did not know that the pus from the sore-laden patients was dripping on their wounds, and they thought it was the same thing as last time, so no one was nervous or afraid.

Only that old Mr. Zhang Wenxuan glanced at Chi Fei meaningfully when he was inoculating.

Chi Fei felt that this shrewd old gentleman might have guessed what it was.

After the 10 death row inmates were vaccinated, almost all of them had symptoms of redness, swelling, itching or rash on the second day.

Chi Fei was very nervous, closely monitored their situation, and designated the place where they lived as a forbidden area, and no one was allowed to enter.

Fortunately, these people's condition did not continue to develop.

After only three days, their symptoms gradually disappeared, and the wounds slowly scabbed and healed, and there were no high fevers, herpes, and other complications like ordinary sore-breaking patients.

At this moment, Chi Fei was already 100% sure that the sores were smallpox.

Although there is no electron microscope to compare the virus samples, it has been confirmed by this way of counter-evidence.

And he really managed to replicate the method of growing cowpox from his world through copycats.

The intense joy made him feel the urge to cheer loudly, but unfortunately because he was in the barracks, he could only endure it.

When Ning Yafeng came in to look for him, she was surprised to see that her brother-in-law was sitting on a chair with a smirk for some reason.

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