(Updates stock prices throughout.)

Despite a global recession and the swine-flu outbreak,

Carnival

(CCL) - Get Report

managed to stay afloat -- and even surpass its second-quarter forecast.

And even though the cruise line lowered its full-year forecast, investors still sent shares up more than 8% in Thursday morning trading to $25.12, before it closed at $24.77. On Friday, the stock continued its upward surge, climbing more than 6% to $26.26 in early afternoon trading.

The cruise line posted a 32% drop in earnings during the quarter, to $264 million, or 33 cents a share, beating analysts' estimate of 29 cents. That compares to a profit of $390 million, or 49 cents, in the year-ago period.

Carnival says the swine-flu pandemic hurt earnings by 3 cents a share, less than the 5 cents expected.

Rival

Royal Caribbean Cruises

(RCL) - Get Report

said the flu will

hurt its earnings by 22 cents

. On Friday, shares in Royal Caribbean nevertheless rose, climbing more than 7% to $14.30.

Carnival's revenue tumbled 13% to $2.95 billion

The company also lowered its full-year outlook due to rising fuel costs. It now expects earnings in the range of $2 to $2.10 a share, down from a prior forecast of $2.10 to $2.30 a share. The company predicts its third-quarter profit should fall between $1.15 and $1.19 a share.

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