Beach reading: "Saving the World"

It's not often that you come across novels about global immunization, but Julia Alvarez appears to have written one, aptly titled Saving the World:

Two women living two centuries apart each face "a crisis of the soul" when their fates are tied to idealistic men whose commitments to medical humanitarian missions end in disillusionment. Alma Heubner's husband, Richard, goes to the Dominican Republic to help eradicate AIDS, while Alma, a bestselling Latina writer, stays at home in Vermont to work on a story about a real, ill-fated 19th-century expedition chaperoned by Dona Isabel Sendales y Gomez, the spinster director of a Spanish orphanage who agrees to vaccinate 20 of her charges with cowpox and bring them from Spain to Central America to prevent future smallpox epidemics.