Numbers in virusy-sent spam headers?

I have been bombarded recently by virusy-spam. The subject lines have the virusy subject headers, like “when” “safety” “re:maybe” “re:work”. There are no attachments, but the body of the e-mails has spam for diet pills, loans, off-shore pharmacies. Each of the messages has a number before the words in the subject line. What are the numbers for? To track the computer sending them? To track the e-mail list?

>> I have been bombarded recently by virusy-spam

What the heck is that? What you describe is just plain old spam. What do you mean by “virusy”?

The subject line, like probably the body, look strange because they are designed to fool spam filters.

To track you!
That is, they are usually unique for each recipient (which also helps the spam get by ISP filters looking for identical messages) and allows them to identify a ‘live’ email address for those foolish enough to reply (or who have automatic preview panes set on their email reader). A ‘live’ email address (one with a known current, active recipient) is much more valuable than a general email address, since a large proportion of them are no longer active.