A child likely died from a rare infection caused by a brain-eating amoeba after swimming in a river, health officials in the US have said.
The child, who has not been named by officials, went swimming in the Elkhorn River in eastern Nebraska on 8 August and developed symptoms about five days later.
The child was in hospital within 48 hours after the onset of symptoms and died 10 days later, according to Douglas County Health Department.
Health officials told a news conference on Thursday that doctors believe the child died of primary amebic meningoencephalitis, a usually fatal infection caused by naegleria fowleri - often referred to as brain-eating amoeba.
The Centers for Disease Control and Prevention (CDC) is conducting tests to confirm the cause of the infection, said Dr Lindsay Huse, director of Douglas County Health Department.
If confirmed, this would be the first naegleria fowleri death in Nebraska's history, the state's Department of Health and Human Services said.
"We can only imagine the devastation the family must be feeling, and our deepest condolences are with them," Dr Huse said in a statement.
"We can honour the memory of the child by becoming educated about the risk and then taking steps to prevent infection."
Naegleria fowleri is a single-celled organism that lives in soil and warm fresh water, such as lakes, rivers, and hot springs.
It is commonly called the brain-eating amoeba because it can cause a brain infection when water containing the amoeba goes up the nose.
Infections are extremely rare, but those who are infected usually die, according to the CDC.
There were 154 primary amebic meningoencephalitis infections in the US in the nearly six decades from 1962 to 2021, and only four people survived.
The amoeba has been increasingly found in northern states in recent years as air and water temperatures rise.
Dr Huse recommended people wear nose plugs when swimming in warm, fresh water.
"Right now, we are simply urging the public to be aware and take precautions when they are being exposed to any warm, fresh water sources," she said.
A person cannot get the infection from swallowing water.
A Missouri resident died in July after likely ingesting the amoeba at a southwestern Iowa lake.