Also, as the article states, this is chloroquine, not hydroxychloroquine. So some difference, that's up to the experts. Zinc a mitigating factor as well?
Anyway, a test in Brazil? I'm not going to get too rapped up about that, nothing against Brazil.
The hydroxychloroquine (or chloroquine) selectively allows he zinc ions to pass into the cell through the cell membrane. The zinc interferes with the virus' ability to enter and replicate and thus take over (and destroy) the cell. Azithromycin also interferes with the viral replication process, as well as wards off some bacterial infections as well.
The reduced damage to the pneumocytes in the lung and the action of the Azithromycin help prevent a cytokine storm, in which the immune system reacts to the degree that it causes more damage to the lungs and kills the patient.
@Absalom As for arrhythmia, among known possible side effects of macrolide antibiotics (of which Azithromycin is one) and hydroxychloroquine/chloroquine is the lengthening of the QT interval, the time it takes between the contraction of the muscles in the
ventricles and the time when they are completely relaxed. Too great an increase in that interval and the heart goes into ventricular fibrillation, which without prompt clinical intervention, is fatal.
These side effects do not occur in all patients normally, and the Brazilian study may indicate dosages which were too high, or a group of patients who were already having problems, through genetics, diet, similar endocrine conditions, or some other individual or assemblage of conditions which can make them more likely to have cardiac arrhythmia.
We don't have enough data to pin down what happened there.