CARACAS, Venezuela -- Venezuelans are expressing dismay over the death of an 8-year-old boy with non-Hodgkin's lymphoma who had become a symbol of the crisis-wracked nation's collapsed health care system.

Oliver Sanchez gained fame in February when he appeared with his mother at a demonstration to protest medicine shortages wearing a mask and holding up a homemade sign reading, "I want a cure, peace and health."

Sanchez died Tuesday, sparking outrage on social media and in congress. Opposition lawmakers in the National Assembly held up pictures of the second-grader to denounce what they called an avoidable death.

Low oil prices and a deep recession are causing widespread shortages in the South American nation, with everything from prescription medicines to basic foodstuffs going scarce.