In a report from Mashable, it seems that WhatsApp is testing out a feature that lets it detect links that might appear to be suspicious and will label it as such, as you can see in the screenshot above. Of course this is only a warning and users can still go ahead and click on the link if they want to, but at the very least they have been warned.
WhatsApp has been taking active steps to try and reduce spam or at least taken steps to help educate their users. For example WhatsApp has started to label messages that have been forwarded to let users know that the message might not have originated from the sender. They have also started to limit the amount of messages that can be forwarded at once to potentially cut down on spam.
Whether or not these tools and features are enough to cut back on spammers using WhatsApp to spread marketing campaigns or conduct scams remains to be seen, but we suppose at the very least they are doing something about it.