Sudden spam overflow in Gmail
 

I have a couple of Gmail accounts, and except for 1 none of the accounts faced any spam issues. Sometimes I'd get only a handful of spam mails in many months combined. Suddenly, one of my Gmail accounts receives a lot of spam. I have to say the spam filter is working very well: all unwanted mail is ending up in the spam folder, so except the loss of time to delete the items in the spam folder, it's still OK. But I wonder what causes the sudden rise of spam.

I thought it could be because the email address was in the WHOIS, but in that case the spam issue would have existed for much longer. Besides, as an EU resident, my data are now automatically hidden on any WHOIS website. So that cannot be the issue, I think.

Could the issue be caused by having received emails from someone who has a lot of spam in their own mailbox? (but in that case, my other Gmail they email to should have a spam issue as well, while this doesn't seem to be the case)

no need to waste time, spam is automatically deleted after 30 days.

True.

I still wonder what causes the sudden increase in spam. Can it be that it comes from someone receiving lots of spam emails having sent an email to that specific email account where I noticed the sudden spam increase? Or is that an unlikely reason for the issue?

Now in theory spam is harmless, you just delete it or --as Gmail does as great job in filtering spam-- you let the spam in the spambox and it gets deleted automatically after a while.
So I'm just curious to know what caused this sudden increase in spam.

You never know--there could be a million reasons, which is why good spam filters are so important. My guess would be someone who has your email address shares that email with other organizations or even sells the list, which is not legal but done all the time. I am a member of a professional organization and every time the member directory is published I receive a ton of spam for awhile. Apparently someone takes all the email addresses from the directory and uses them for sending out spam. I also know of people who not thinking include many email addresses in the open when sending to groups of people--someone seeing that email come in may then add your name to his/her lists, and on it goes...Here's one article about it: http://www.pcassistonline.co.uk/Help...solutions.html

IMO it's only harmless if you get zero FPs, otherwise spam make the FPs harder to spot.