By Billy Hammond (Copyright AELS)

If you haven’t read Part 1, which describes the general characteristics of E. coli, you might want to take a look at it before reading this installment. Information on enterotoxigenic (ETEC) can be found in the 2nd article in this series. See the 3rd article for a discussion of enteropathogenic (EPEC). The 4th article covers enterohemorrhagic (EHEC); enteroinvasive (EIEC).

Transmission of E. coli as a disease is usually via the fecal-oral route. Food and water often provide transport for infections.

There are five types of E. coli infections that have been identified so far: enterotoxigenic (ETEC); enteropathogenic (EPEC); enterohemorrhagic (EHEC); enteroinvasive (EIEC); and enteroaggregative (EAEC).

5. Enteroaggregative E. coli (EAEC).

EAEC is another cause of traveler’s diarrhea (the most common cause is ETEC) and accounts for about 25% of all cases.

EAEC adhere to the small intestine through their thread-like projections (fimbriae). The rods form a brick-like pattern that helps to differentiate them from the other strains. The strains produce a heat-stable toxin that is plasmid encoded.

An EAEC infection progresses in three stages. In the first stage, the enhanced production of mucus encases the bacteria in a biofilm on the intestinal mucosa. In the second stage the cytotoxin kills the intestinal cells and in the final stage the cell damage results in a watery diarrhea.

In contrast to the ETEC induced traveler’s diarrhea, which usually resolves in 24 hours after fluid replacement therapy, EAEC tend to run a course of several days.

Although rare, a hybrid strain of EAEC, which managed to produce a Type 2 Shiga-like toxin in Germany in 2011 caused several deaths and many cases of HUS.

大腸菌: Escherichia coli (E. coli) 5

パート1を読んでいなければ、先に読むのを薦める。

ETEC(腸毒性大腸菌)についてパート2

EPEC(腸病原性大腸菌)についてパート3.

EHEC(腸出血性大腸菌)EIEC(腸侵入性大腸菌)についてパート4を参照。

E. coliの病気としての伝染は通常糞口経路で行う。感染された食べ物や水が普段輸送経路となる。

今まで5種類のE. coli感染が確認されている: 腸毒性大腸菌 enterotoxigenic (ETEC);腸病原性大腸菌enteropathogenic (EPEC); 腸出血性大腸菌enterohemorrhagic (EHEC); 腸侵入性大腸菌enteroinvasive (EIEC); 及び 腸管凝集性大腸菌 enteroaggregative (EAEC)

5. 腸管凝集性大腸菌 enteroaggregative (EAEC)

EAECは約25%の旅行者下痢症の原因である(最も多い原因はETEC)。

EAECは糸のような線維(細菌線毛)で小腸に付着する。重なるロッド形状は独特なレンガのようなパターンに並ぶため、他の菌株との識別に役立つ。EAEC菌株はプラスミドにコードされた耐熱性毒素を生産する。

EAEC感染は3段階で進行する。初期段階では粘液過分泌でバクテリアが小腸粘膜上でバイオフィルムで覆われる。次の段階で細胞毒素が腸細胞を殺し、続けてその細胞破壊により水様性の下痢が起きる。

通常、補液療法で24時間で治るETEC旅行者下痢症と異なり、回復までEAECの下痢は数日間掛かる。

非常に珍しいだが、2011年にEAECの交雑株がタイプII志賀毒素と似た毒素の生産が出来て、数人の死亡者が出たうえ、数多くの溶血性尿毒症症候群(HUS)症例もみられた。

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English books by Billy Hammond published by AELS

(AELS出版英語書籍リスト)

 

I. Majoh Gakuin and Hikari Juku – Japanese Witch Schools Trilogy

1. Majoh Gakuin & Hikari Juku – Japanese Witch Schools

2. Lost Witch (The second book)

3. Fate & Magic (The final book in the trilogy)

II. Brindle – Scryer Extraordinaire Trilogy

1. Brindle – Scryer Extraordinaire

2. Brindle – Scryer Extraordinaire – Returns

3. Brindle – Scryer Extraordinaire – Challenges (The final book in the trilogy)

III. Fantasy fiction set in Japan

1. 21st Century Ninja

2. Regressed

3. Japanese Woman

IV. Fantasy fiction set outside of Japan

1. Dimension Jumpers

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