Brazil hit the grim mark of half a million COVID-19 deaths Saturday, a toll second only to the U.S. that shows few signs of easing. Yet residents are spurning vaccines that they believe are substandard in favor of hard-to-find shots from Pfizer Inc.

In Sao Paulo, people demand the U.S. company¡¯s shots at public clinics and often walk out if none are available. Some health care centers have put up signs saying ¡°no Pfizer shots¡± to save time. Many vaccination centers are empty, and the few that have Pfizer have massive lines.

Maressa Tavares, a 29-year-old teacher, could have gotten her shot two weeks ago in Rio de Janeiro. But at the request of her father, she¡¯s holding out for Pfizer. ¡°For me, it didn¡¯t make a lot of difference which one to take, but my father has very strong beliefs,¡± she said.