Amy Cassidy, CNN
(CNN) - An elderly Dutch woman has become the first known person to die from catching Covid-19 twice, according to experts, raising serious questions about how long immunity and antibodies can last.
The woman, 89, suffered from a rare type of bone marrow cancer called Waldenström's macroglobulinemia. Her immune system was compromised due to the cell-depleting therapy she received, the researchers at Maastricht University Medical Center in the Netherlands wrote in a paper accepted for publication in the journal Clinical Infectious Diseases.
However, the researchers said her natural immune response could still have been "sufficient" to fight-off Covid-19, as the type of treatment she received for cancer "does not necessarily result in life threatening disease."
The patient was initially admitted into hospital earlier this year with a severe cough and fever, testing positive for Covid-19.
She was discharged five days later when "besides some persisting fatigue her symptoms subsided completely," according to the report.
But two days into chemotherapy treatment -- 59 days after the start of the first Covid-19 episode -- the woman developed fever, cough and difficulty breathing.
She once again tested positive for coronavirus, and no antibodies were detected in her blood system when tested on days four and six. Her condition deteriorated on day eight.
Two weeks later, the woman died. Read more >>