Paola Bezzon thought her sniffles in December were just a seasonal cold until a serology test months later found coronavirus antibodies in her blood. And not just normal levels of antibodies. Researchers say she is "super-immune" — a person whose body seems to make more antibodies than normal. "I don't know why I have all these antibodies, but they are such a lifeline for me," she said. "They make me feel safe even though I haven't had the vaccine yet."