マイコプラズマ肺炎 全国の患者増［2024.8.13］

子どもに多くみられ、長引く咳が特徴の「マイコプラズマ肺炎」の患者が8年ぶりの水準で広がっています。“歩く肺炎”とも呼ばれる感染症。拡大の背景に何があるのでしょうか？

クリニックばんびぃに　時田章史 院長
「コロナとインフルは陰性なんですけど、マイコプラズマが陽性に」

都内の小児科クリニック。この2週間、「マイコプラズマ」の患者が急増しています。

「マイコプラズマ」という細菌に感染すると、発熱や咳などの症状が出て「マイコプラズマ肺炎」を引き起こすこともあります。咳が長引くのが特徴で、1か月続くこともあるといいます。

時田章史 院長
「診断名はマイコプラズマ。マイコプラズマ肺炎まではなっていないと思うけど、抗菌剤と咳止めを処方しておきます」

この9歳の女の子は熱が下がっても1週間、咳が止まらないといいます。

9歳の娘を連れてきた父親
「咳が長引いていたので、心配になって来ました。（Q.なかなか治らない？）そうですね、治らない感じですね」

きょうも午前中だけで3人、感染が確認されたといいます。

全国のおよそ500の医療機関に、今月4日までの1週間に報告された「マイコプラズマ肺炎」の患者は5週連続の増加となり、1医療機関あたり0.95人。過去最多だった2016年以来、8年ぶりの高い水準です。

旅行帰りだという3歳の女の子も発熱を繰り返し、咳の症状も出てきたため、受診。

3歳の娘を連れてきた母親
「1回、夜中に熱が上がってきて。（Q.咳は今のところちょっと出ているくらい？）ちょっと出ています」

検査の結果、マイコプラズマへの感染が確認されました。

コロナ禍で免疫が減ったことに加え、拡大の背景に指摘されるのが“潜伏期間の長さ”です。時田院長によると、「マイコプラズマ」は感染から発症までが2～3週間と潜伏期間が長く、気付かないうちに学校などで感染を広げやすいと話します。

時田章史 院長
「潜伏期が2週間なので、沖縄（旅行）に行ったのは1週間くらい前？」
母親
「いや、全然、この週末に行ってきた」
時田章史 院長
「じゃあ沖縄でもらったというよりも、（旅行前）こちらにいる時に感染していたと思う」

保護者は受診のサインにどう気付けばいいでしょうか？

時田章史 院長
「風邪でしょうと言っても、そこからまた熱が3日4日続く。最初はそうでもなかったけど、3日目4日目くらいから咳がかなり、またひどくなってきた場合、一回受診していただくといいかなと思います」

厚生労働省は、手洗い・マスクなど基本的な感染対策を呼びかけています。

■英訳　

Cases of "Mycoplasma pneumonia," characterized by prolonged coughing and often seen in children, are spreading at levels not seen in eight years. This infectious disease, also known as "walking pneumonia," is on the rise. What is behind this increase?

Dr. Akifumi Tokita, Director of Clinic Bambii
"The patient tested negative for COVID-19 and influenza, but positive for Mycoplasma."

At a pediatric clinic in Tokyo, the number of patients with Mycoplasma has surged over the past two weeks.

When infected with the Mycoplasma bacterium, symptoms such as fever and cough can occur, and it may lead to "Mycoplasma pneumonia." A distinctive feature of this illness is a prolonged cough that can last up to a month.

Dr. Akifumi Tokita
"The diagnosis is Mycoplasma. I don't think it has developed into Mycoplasma pneumonia, but I will prescribe antibiotics and cough medicine."

A 9-year-old girl has been coughing for a week even after her fever subsided.

Father of a 9-year-old daughter
"I was worried because her cough persisted. (Q: Hasn't she gotten better?) No, it doesn't seem to be getting better."

Today alone, three cases of infection were confirmed in the morning.

The number of patients with "Mycoplasma pneumonia" reported to around 500 medical institutions nationwide in the week leading up to August 4th has increased for five consecutive weeks, with an average of 0.95 patients per medical institution. This is the highest level seen in eight years since 2016, when the number of cases was at its peak.

A 3-year-old girl, who had just returned from a trip, also showed symptoms of fever and coughing, prompting her mother to bring her to the clinic.

Mother of a 3-year-old daughter
"Her fever spiked once during the night. (Q: Is she coughing a little now?) Yes, she is coughing a little."

Test results confirmed that she had contracted Mycoplasma.

In addition to weakened immunity due to the COVID-19 pandemic, the long incubation period is being pointed to as a factor in the spread of the disease. Dr. Tokita explains that Mycoplasma has a long incubation period of 2 to 3 weeks from infection to the onset of symptoms, making it easy to unknowingly spread the infection in places like schools.

Dr. Akifumi Tokita
"The incubation period is two weeks, so did you go to Okinawa (on your trip) about a week ago?"
Mother
"No, we just went this past weekend."
Dr. Akifumi Tokita
"Then, it's more likely that the infection occurred before the trip rather than in Okinawa."

How can parents recognize the signs that their child needs medical attention?

Dr. Akifumi Tokita
"If you suspect a cold, but the fever continues for three to four days, or if the cough wasn't too bad at first but worsens around the third or fourth day, it might be a good idea to bring your child in for a check-up."

The Ministry of Health, Labour and Welfare is urging people to practice basic infection prevention measures such as handwashing and wearing masks.

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