The first case of brain damage linked to the Zika virus within the United States was reported on Friday in Hawaii.

The Hawaii State Department of Health said that a baby born in an Oahu hospital with microcephaly — an unusually small head and brain — had been infected with the Zika virus, which is believed to have caused the same damage in thousands of babies in Brazil in recent months. The presence of the virus was confirmed by the Centers for Disease Control and Prevention.

The child’s mother had lived in Brazil in May last year and probably was infected by a mosquito then, early in her pregnancy, the health department said. The virus presumably reached the embryo and damaged its developing brain.

“We are saddened by the events that have affected this mother and her newborn,” Dr. Sarah Park, Hawaii’s state epidemiologist, said in a statement. “This case further emphasizes the importance of the C.D.C. travel recommendations released today.”