KUWAIT CITY — Several swine flu cases have been detected among U.S. soldiers passing through Kuwait, officials said yesterday.

A Kuwaiti health official says all 18 U.S. soldiers infected with swine flu have since recovered.

The official, Youssef Mandakar, said today the soldiers entered Kuwait by air and didn't have any contact with the local population. He said their cases were "mild" and they have all left the country. He wouldn't say where they came from or their destination. The U.S. Embassy said cases have "tentatively" been confirmed without providing details.

"Each case was characterized as being a mild flu-like symptom," the American military said in a statement. "All but ... a couple have been treated and returned to duty."

Oil-rich Kuwait is an ally of Washington and a logistics base for U.S. military personnel serving in Iraq.

The Kuwaiti health official said no other swine flu cases have been detected in the country.

The World Health Organization's global tally now stands at 12,022 cases of swine flu and 86 deaths in 42 countries. More than half of those cases have been reported in the United States, while most of the deaths occurred in Mexico. The virus was first detected last month.

Iceland has confirmed its first case of swine flu, chief epidemiologist Haraldur Briem said in a statement.

The victim is a person who returned from abroad about a week ago, according to the statement on the Directorate of Health's Web site yesterday.

Four suspected cases, involving members of the traveler's family, are being investigated, Briem said. All live in the capital Reykjavik and the southern part of the country, according to the statement.

Meanwhile, Japanese schools started to reopen as fears that swine flu may spread nationwide eased, prompting the government to leave local authorities in charge of dealing with outbreaks of the virus.

Hyogo Prefecture's Kobe, the city famous for its marbled beef, on May 16 had the first confirmed case of the H1N1 virus in someone who hadn't traveled abroad. The prefecture's entire school system, including many day-care facilities, was shut as a result. Hyogo reopened facilities as of yesterday, while neighboring Osaka Prefecture announced it will resume classes tomorrow.

The Associated Press and Bloomberg News Service contributed to this story.