The family of an 8-year-old Rapid City boy says he has died of the swine flu.

The family of third-grader Jack Unkenholz says he died Sunday at a local hospital. If the death is confirmed it would be the third in South Dakota attributed to the H1N1 virus.

South Dakota's first two swine flu deaths were residents in their 30s and 40s. The Health Department did not identify them, citing privacy rules.

Jack Unkenholz's mother, Tasha, says her son had other health problems that made him more vulnerable to the flu.

The state has begun distributing 16,000 more doses of swine flu vaccine to 280 clinics and hospitals across South Dakota, but officials say they still do not have as much vaccine as they need. State Epidemiologist Lon Kightlinger calls the situation "very frustrating."

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