The wife of murder-accused George Gwaze has told the High Court in Christchurch she did not know her niece was HIV positive until she died.
Gwaze, 60, is accused of sexually violating and suffocating his niece, 10-year-old Charlene Makaza, in 2007.
The crown says the Zimbabwean veterinarian suffocated and sexually attacked Charlene, who was also his adopted daughter, while she was in bed in January 2007.
Defence lawyers say Charlene died of natural causes complicated by her being HIV positive.
Gwaze's wife, Sifiso Gwaze, 57, told the court she had started to suspect her niece may have the disease but had never had her suspicions confirmed until Charlene was in Christchurch Hospital, just before she died.
She described the medication brought to New Zealand for Charlene's ongoing infections and that Charlene had visited a Christchurch GP four times until her death in 2007.
The trial is expected to take four weeks.