BUENOS AIRES, Argentina (AP) -- Two intensive-care patients contracted HIV after receiving blood transfusions at public hospitals in the Argentine province of Cordoba, a newspaper reported Friday.

An unidentified donor gave blood at a Cordoba city hospital in December, testing negative for HIV, Health Minister Oscar Gonzalez was quoted by Cordoba's La Voz del Interior newspaper as saying.

When the donor returned in May to give blood again, tests came back positive for the virus -- but the blood had already been distributed, the newspaper said, citing Gonzalez.

Officials alerted local hospitals, and two patients were this week found to have been infected after receiving blood transfusions from the donor, who likely contracted HIV shortly before he or she gave blood in December, Gonzalez said, according to the newspaper.

The newspaper did not identify the donor, the hospital or the infected patients, in line with a national law that that does not allow such information to be disclosed publicly.

A so-called "window period" of 16 to 22 days can pass between exposure to HIV and the time antibodies can be detected in a standard blood test. During that time, a person can be contagious.

As in the U.S., blood donors in Argentina are given an extensive questionnaire to limit high-risk donors, who officially include gay men who've had sex in the past five years, people who've had sex for money or drugs in the past five years, or used intravenous drugs recreationally during that time.

About 120,000 people are infected with HIV in Argentina, Latin America's fourth-most populous nation, which also has the fourth-highest number of cases in the region, according to the U.N.

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