Mission accomplished

Born and raised in wartime Shanxi, Eugene Wampler's life came full circle when he returned to China to help develop a vaccine that would go on to save millions of lives, Zhao Xu reports in Harleysville, Pennsylvania.

In 1922, Elizabeth Wampler, a nurse who had been sent to work in China by the Christian church, had a photograph of her taken with Chinese twin brothers, children that she had either treated or helped to deliver, in southern Beijing.

Thirteen years later, Wampler, whose time in China extended far beyond that point, had two boys of her own - one born in 1933 in a village in Shanxi province, North China; the other in 1935 in a village 200 kilometers further southeast.