Outdoing most analysts' worst predictions, spam accounted for 82 percent of all U.S. email last month.

After a two-month drop in spam, the number of unsolicited bulk email skyrocketed in April, bringing the saturation number up to record levels here in the U.S. and across the world, according to MessageLabs, Inc., a security company based in New York.

''This is as bad as we've seen it,'' says Paul Wood, chief information security analyst for MessageLabs. ''I think it's likely that it will continue to rise but perhaps not at the same rate that it did in the past month.''

And April did show a dramatic increase.

According to Wood, spam was on a steady increase last year, going from a 50 percent saturation in the middle of 2003 to 63 percent in January of this year. But then there was a largely unexpected sharp decline. February saw the rate drop to 59 percent, and March was even lower at 52.8 percent. That means in March, spam accounted for 52.8 percent of all the email traveling around the world.

But that drop was short-lived.

In April the rate shot back up, surpassing the January high, to hit 67.6 percent globally. And here in the United States, it hit 82 percent.

''You have to wonder if this will eventually affect people using email,'' says Wood. ''We haven't seen a decrease in email usage but we'll have to see how high the numbers go.''

Earlier in the year, security analysts warned that spam was increasing at such an alarming rate that they expected it to make up 80 percent of all email by the third quarter of 2004. That prediction was several months off.

And spam has a big market to target.

The Radicati Group, Inc. reports this week that there now are 980 million active email accounts around the world, and 40 percent of those are corporate accounts.

Wood says he attributes the drop in spam during February and March to the CanSpam Act that went into effect this past January. He adds, though, that the act, which has been criticized for not having enough enforcement teeth and for allowing far too much unsolicited email to continue to flow legally, hasn't stopped spamming. Wood says he figures that the major spammers just slowed down operations so they could figure out how to better dress up their spam to make it appear to fit into the legal limits.

Once that was done, they could resume operations with even more force.

''It's not legitimate,'' says Wood. ''It's just dressed up to make it look that way.''

Wood also attributes the rise in spam to the huge number of open proxies on the Net.

Virus writers began teaming up with spammers last year, and so far it's been a dangerous combination. Virus writers send out malicious code that infects computers and opens a back door in the machine. A hacker then can use that back door to remotely control the computer, sending out more viruses, Denial of Service attacks or millions of pieces of spam.

Wood estimates that 70 percent of spam is sent through open proxies.