Federal health authorities on Friday reported the first death related to the Zika virus on US territory.
An elderly man died from an autoimmune reaction to the virus in February on the Caribbean island of Puerto Rico, a US territory, the Centres for Disease Control and Prevention (CDC) announced.
The man in his 70s died from internal bleeding after developing immune thrombocytopenic purpura (ITP), which keeps the blood from clotting, the Washington Post reported.
Others with the Zika virus have died from the same condition in Latin America.
Puerto Rico, which lies east of the Dominican Republic, has had 707 confirmed cases of the virus.
In February the World Health Organization (WHO) declared Zika virus a public health emergency of international concern, and in March said that Latin America could be faced with thousands of neurological birth defects in the wake of current Zika outbreaks.
Two weeks ago, the CDC confirmed that the Zika virus causes microcephaly, a condition in which babies have abnormally small heads and brains, leading to sometimes severe developmental impairment.
Scientists in Brazil and other Latin American countries, where there are active outbreaks of the Zika virus, have long believed that the virus causes microcephaly.
The CDC said it reached the conclusion after careful review of existing evidence, noting that Zika also causes other severe fetal brain defects.
The findings support early guidance to pregnant women and their partners to take steps to avoid Zika infection. The CDC has warned that pregnant women should avoid travel to areas where Zika is actively spreading.
Many questions remained about the virus, which is spread by mosquitos and sexual contact. For example, scientists do not know why some infected women have delivered babies that appear to be healthy.
In addition to microcephaly in newborns, the virus has been linked to rising numbers of cases of Guillain-Barre syndrome in adults. This neurological disorder can lead to paralysis.