Back on earth, John Snow, a British based physician founded what the modern medicine call as epidemiology study and thus he's titled as father of epidemiology. Since I can see this endemic seasonal disease follow the same pattern as John's case, I decided to use his approach. 

Unlike John Snow though, I have a head start. John Snow have to interview the relative of the deceased in order to found out about the source of infection then only he came to the conclusion that the well use by the British during that time was indeed infected by Cholera. As for me, I decided to straight away look at each well and also the public around the city. It's simple since I already have the knowledge.

"Take care" [Karon]

"You really want to come along didn't you" [Ash]

"..." [Karon]

Well, I'm reluctant to let him go. I am investigating an endemic disease. Eventhough I know about the disease transmission, I'm still reluctant to let him come along. Kid have lower immunity as compared to us adult, so yeah, I won't budge on this one. 

"Come now Karon, let us help the other" [Diana]

"..." [Karon]

"Well, please take care of them" [Ash]

"We will" [Samurai Jacks]

Right now inside the mansion, there're few people, such as Diana and Qis. Seriously, I might have cured her, but that doesn't mean she should be working straight away. Even Diana prohibited her, and yet she is still standing strong. Well, if she suddenly fell off due to weakness, there're three healers here, namely Rafiah, Yefefiah and also another female young healer. There're also the adventures that had been hired by Diana and lastly, there's Liyana. She came early in the morning to train with me, but sadly I have works to do. Luckily Qis volunteer to teach not only her, but my siblings as well. Still...

(Qis and Alice, I swear I can see some strange reaction in their face when Liyana came in just now) [Ash]

There might be a hidden story, but I'll save it for later. Ohh, and there's also Alice who come here early in the morning as well. She will be there to help me, but her true mission as stated by Ram is to make sure I don't land up in any sort of trouble. How rude, but I can't deny it

"Buy us some orange grass on your way home!" [Mara]

"Sure" [Ash]

Orange grass, just like its name, it's basically an orange shape like a grass. To eat it, you simply have to wash the grass to peal off a thin layer of membrane and then, eat it. That's it. It has the same property as that of an orange so that's why when they say they like the orange grass, I don't have any problems on buying it.

As Alice and I plan the location of wells and public toilets that we will visit, I catch the glimpse of Rafiah's friend, trying to peek at the mansion. Just how did you know where Rafiah stays right now? Should I approach and tell her to go. 

(No, bad idea. Let just hope Housey and Claude will protect her) [Ash]

Plus, she's all alone. I don't think she will create much problem (let just hope so). If she does create any sort of trouble, there's Qis and other adventures there as well.

"We should start here first" [Alice]

"Yeah, it's nearby" [Ash]

Alice interrupted my train of thought. Still, this well is nearby, so I guess there's no need to use the bus golem. It's a distance coverable just by walking for 10 minutes. 

As we walk by, I can see some wave of people going to the mansion. They must have come to seek treatment after Diana and the other spread have spread the news, saying that the castle under her supervision will give out free treatment. I just hope everything will be fine in her end

As we're approaching the well, I can see three familiar figures, aren't they...

"Flinar, Erinmorlin, and Lisa, what are you doing here?" [Ash]

"Ahh, the Behemoth Slayer. We just finished looking into the causes of medication prices surge for today" [Flinar]

"This early?" [Alice]

"Yeah, there's nothing much to investigate in this area, maybe due to certain someone living nearby" [Erinmorlin]

"Isn't that good" [Ash]

"Well, what about you two?" [Lisa]

"We are looking into the cause of the disease. Right now we are visiting each and every wells and public toilets inside the city" [Ash]

"Interesting, can we join!" [Lisa]

Lisa eyes brimming with interest, she's a scholar after all, so this kind of thing will definitely catch her interest. The same can be said to the mid life elf Flinar as well as the mid life dwarf, Erinmorlin. No reason not to let them in, plus Lisa herself is a scholar, she can give some insight from her perspective

"Sure, come along" [Ash]

As we walk, I explained to all four of them regarding the disease transmission, the symptoms and what shall we do to treat it.

"Who taught you all this?" [Lisa]

"My mother, she's a healer after all" [Ash]

"Ohh, wish I can meet with her" [Lisa]

"Same here..." [Ash]

It's short, but I do get the chance to meet with her. Ever since that day when I treat Borg and Lin, I have tried my best to call the soul of both my father and mother, but sadly nothing happen. Are there any conditions that are needed to be fulfilled? If so what? Seeing the needy? Possible

"There's the well" [Flinar]

"Well, well, well as expected, it's dirt alright. Plus, the public toilet is nearby as well" [Ash]

"How long have you been planning on saying that awful pun" [Erinmorlin]

"Shut it! Plus, I'm sure those kids will laugh hearing it" [Ash]

"Dad jokes warning" [Alice]

"Haha" [Lisa]

Dad jokes aside, I have to start investigating. First, need to confirm that those who are sicked do use the well here, so I have to conduct an interview. I also need to look into the drainage system, whether it's connected to the well or not. There isn't a record about it in the castle, and the Duke refuses to give it to me, even with the contract given to me by the king. 

"I can help in interviewing the local. It's a scope of job for a scholar" [Lisa]

"The same can be said to me, a receptionist" [Elise]

"As for the drainage system, I can use my earth sonar magic and see underneath the ground" [Erinmorlin]

"Thanks everyone" [Ash]

As for Flinar, he has been looking at something for a while now.

"Ash, you might want to see this" [Flinar]

"What is it?" [Ash]

He pointed out to a slimy substance alongside with trace of fecal matter. Ughh... gross

"And..." [Ash]

In annoyed voice, I ask him.

"Well, the fecal aside, this slimy substances is characteristic of Lou Carcolh, a serpentine mollusk and based on my experience, anytime the mollusk appear on large quantities, it will spell disaster" [Flinar]

"I see, but just what could it eat?" [Ash]

"Well, you did say something about the faulty drainage system being the source of transmission. If we are to assume that the drainage system of the city are having number of problems, then I can assume some wild monsters make their nest down there and those monsters in turn attract Lou Carcolh" [Flinar]

"I see, monster inside the city. This is bad" [Ash]

"Not the first time, and surely not the last" [Flinar]

While monster typically and mostly found inside the dungeon, there's time when they can exist inside the city. Rare, but it does happen. The random malignant wormhole summoning the behemoth is an example of it. As for this case, who knew. Need to investigate it further

As we discuss the possibility, Erinmorlin has finish using his magic, and as expected, the well and the public toilet do connected

As for Alice and Lisa, they have confirmed that the people here do take their water from the well, which lead to a question

"If the faulty drainage is to be blamed, then just why is it only happen once a year? Plus the dates it happen almost the same from year to year" [Ash]

"Maybe..." [Alice]

"Any idea?" [Erinmorlin]

"Well, the Duke's household do responsible for maintaining the drainage, as well as collecting some taxes regarding things like this. As for why it's only happen during this time of the year, this might be a coincidence, but they're making the maintenance of it around this time of the year" [Alice]

"I see, either the maintenance causes the faulty drainage system and thus causing the disease, or the Duke's household could have realized this problem but chose to keep silence about it, and only send maintenance to prevent further spread of the disease" [Lisa]

"Well, only one way to find out" [Ash]

"Let just move to next location" [Flinar]

To move to the next location, I simply drive my bus golem with those four as passenger