Power utility Eskom on Wednesday called on consumers to switch off geysers, pool pumps and all non-e.
A regional prosecutor's office in Bern, the Swiss capital, says the unidentified man was indicted in Bern-Mitelland regional court on charges of intentionally spreading human disease and causing serious bodily harm, offenses that carry maximum penalties of five to 10 years respectively.
Prosecutors said in a statement that most of the victims attended his music school and that the defendant injected them with infected blood under various pretexts by pricking them with unknown objects or using a drink that made them pass out. They say the defendant "denies everything."
Prosecutors say proceedings against a second suspect have been closed for lack of evidence.