What does this have to do with immigration? There have been tuns of cases where this has happened. There was a guy in New york that did this in mid 90s and spread virus to something like 12 women. This is one of the first cases to levy murder charges. It isn't an immigrant specific problem. Certain cultures aren't as educated to risk of unprotected sex but that requires education. If you went back 20-30 years the culture as a whole in US or Canada was properly educated on HIV.

This is off wiki for criminal HIV cases:

Nadja Benaissa (born 1982) German female pop singer who was convicted of knowingly infecting a number of her lovers.
Henry Cuerrier Canadian man convicted of aggravated assault for knowingly exposing two women to HIV.
Carl Leone (born c.1976) Canadian businessman found guilty of 15 counts of aggravated sexual assault for not informing his partners of his HIV status.
Andre Chad Parenzee (born c. 1971) South African-born man convicted in Australia on three counts of endangering human life through having unprotected sex without informing his partners of his HIV status.
Trevis Smith (born 1976) American player of Canadian football with the Saskatchewan Roughriders, jailed for aggravated sexual assault.
Nushawn Williams (born 1976) American who infected 13 women with HIV; imprisoned for reckless endangerment and statutory rape.

This is cases in Canada that involved HIV Virus:

1991: Charles Ssenyonga is charged with criminal negligence causing bodily harm, after allegedly infecting 17 women. He is the first Canadian criminally charged for passing on AIDS. He died before a verdict was reached.

1991: Ray Mercer, 28, of Newfoundland is also charged with criminal negligence causing bodily harm for exposing a number of women to the virus through unprotected sex. He was convicted and sentenced to 11 years in jail.

1995: Henry Cuerrier exposed two women to the virus through unprotected sex and was charged, but a British Columbia judge acquitted him on the grounds that the women consented to sex, even though he had lied about his HIV status to one partner, and hid it from the other. It was overturned by the Supreme Court in a 1998 decision that ruled that failing to inform a partner of one's HIV status was effectively fraudulent and voided the consent and as such constituted the crime of aggravated sexual assault.

2005: Patrick Green, 29, of St. Catharines is charged with aggravated sexual assault for failing to tell his sexual partner of his HIV status.

2005: Canadian soldier Jennifer Murphy, 31, pleaded guilty to aggravated sexual assault for incidents of unprotected sex with two partners she hadn't told about her HIV infection. Neither victim has developed the disease. Murphy was sentenced to one year of house arrest and three years probation.

2007: Robin Lee St. Clair, 26 of Hamilton, is charged with sexual assault for exposing a Toronto man to the virus by not disclosing the fact that she had been infected by HIV, the investigation expands to include men in Brantford and Hamilton as well. Four years earlier, sparked by a tip that came in the wake of publicity surrounding Aziga's arrest, Hamilton police identified five men the single mother admitted to having unprotected sex with. None would co-operate with police and so no charges were laid.

2007: Trevis Smith, former Saskatchewan Roughrider, is sentenced to 5 1/2 years in jail for knowingly exposing two sexual partners to HIV.