Del Mundo graduated from the University of the Philippines College of Medicine in 1933 and pursued postgraduate work in pediatrics and bacteriology in the United States. She trained or worked at several institutions, including Boston Children's Hospital, before returning home in 1941.
She later held academic and professional leadership roles and became the first woman named National Scientist of the Philippines in 1980. Awards reflected a long career, but institutions, staff, public programmes, and trained successors made that work sustainable.
Her emphasis on affordable equipment and community services responded to material limits rather than treating resource-constrained medicine as an inferior copy of wealthy systems.