The New Jersey Department of Health and Senior Services said Monday that all have mild forms of the flu and none has been hospitalized.
The department says it's arranging for confirmatory testing at the federal Centers for Disease Control and Prevention. Results are expected within two days.
The patients include residents of several counties. Four recently traveled to Mexico; the fifth had traveled to California.
Mexico is considered the epicenter of the swine flu outbreak, with 149 suspected deaths and nearly 2,000 people believed to be infected. California has several confirmed cases.
The New Jersey cases were identified through preliminary tests conducted at the New Jersey Public Health and Environmental Laboratories.
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