The case is a woman who is being quarantined at home after travelling to New Zealand.
The local resident had already spent 14 days in quarantine in Samoa before arriving in the territory on 14 March.
Department of Health Epidemiologist Aifili Dr John Tufa said two days before she arrived in American Samoa she developed a slight cough.
She had been given a three day health clearance by the Samoa's Ministry of Health.
A few days later she started having breathing problems and called the Department of Health.