A caregiver for an elderly Utah man who died while infected with Zika tested positive for the virus but has recovered, health officials say.
The US Centers for Disease Control and Prevention on Monday said it had confirmed that a person who helped care for the man who died last month while infected with Zika contracted the virus.
But, it said the patient recovered quickly.
Utah officials said the infected caregiver had not had any recent travel to an area where the Zika virus is being transmitted nor had the person had sex with an infected individual.
Utah officials are still investigating how the person became infected.
Gary Edwards, director of the Salt Lake County Health Department, said the infected individual is a family contact of the man who died.
Edwards would not say how old the family contact was nor release the person's gender.
"We know that the patient had contact with the deceased patient while the deceased patient was very ill. The exact nature of that contact, we are still investigating," he said.
Edwards said the cause of the deceased person's death is still under investigation, but the man was infected with Zika at the time of death and officials believe the virus was a contributing factor.
The CDC said in a statement that testing showed extremely high levels of virus in the deceased man's blood, which were more than 100,000 times higher than seen in other samples of infected people.
Tom Hudachko, director of communications for the Utah Department of Health, said the case is unique because the infected individual does not have any of the known risk factors associated with Zika.
Hudachko said state officials are not aware of any mosquitoes known to carry the Zika virus within Utah.
He said there were a few Aedes aegypti mosquitoes - the kind that carry Zika - discovered in traps in the southwestern parts of the state several years ago, but there have not been any since.
He said the state does not have any Aedes albopictus mosquitoes, the other type that has been found capable of transmitting Zika.