Once a year, doctors travel to Rwanda to perform lifesaving surgery on people with damaged heart valves — a disease caused by untreated strep throat.

By Denise Grady

KIGALI, Rwanda — Neighbors whisper that she is pregnant, a disgrace for a young, unmarried woman. The rumors mortify her. She hates her swollen belly.

But Florence Ndimubakunzi is not pregnant. Her heart is failing. It pumps so poorly that blood backs up in her veins, bloating her liver and spleen, and filling her abdomen with fluid. She is only 18.

For millions like her in poorer parts of Africa, Asia and other regions, this devastating heart disease began insidiously. During childhood, they contracted strep throat — an infection caused by streptococcal bacteria.

In the United States and other rich countries, children with sore throats are routinely tested for strep and quickly cured with penicillin or other cheap antibiotics.