Thinking it was only some common disease, Jack and his wife didn't take the boy to the hospital.

杰克和妻子以为这只是普通疾病，没有送孩子去医院。

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On the 20th of that month, Dr. Welch examined a sick boy, Billy, and knew he had diphtheria, a deadly infectious disease mainly affecting children.

在那个月的20号，韦尔奇博士检查了一个生病的男孩比利，得知他患了白喉，一种主要影响儿童的致命传染性疾病。

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Old mother, looked to be a very tough battle on the disease afflicted mother, the boy grief, and tears.

母亲老了，望着被病魔折磨得死去活来的母亲，男孩悲痛欲绝，潸然泪下。

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People with SCID -- also known as "bubble boy disease" -- cannot cope with infections and usually die in childhood.

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One piece of context that led me to think differently: via Emily Willingham, this article on how Instagram was helping one many share the story of a boy with a rare disease.

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And in San Diego, a measles outbreak in 2008 was traced to an unvaccinated 7-year-old boy who contracted the disease in Switzerland and passed it on to 11 other unvaccinated children, including in his family, his school and his pediatrician's office.

WSJ: Where Could The Next Outbreak Of Measles Be?