I take your understanding of enhance and deteriorate as the background, and this part: "Is there a similar elegant way to express 'there is more (something), and this is a bad thing'?" as the real problem. And this problem is about expressiveness in writing (and/or speaking). In other words, it's about how to sound more natural, more idiomatic, and have a good writing style.
In my opinion, you may be asking the wrong question. There might be a stock phrase in your first language for "there is more X and this is a bad thing" whatever X is. (I don't know this, but because you're asking this, it suggests that this might be true.)
As far as I can see, English is not like that. In English, a) some words usually go together, which means that we don't have a universal phrase that works in all cases of X, and b) when it's general enough, the connotation of "this is a bad thing" is not in the phrase, but in X itself.
Here are some examples.
a) When the noun (i.e., X) dictates the verb:
Viruses multiply.
Health deteriorates.
Problems escalate.
Poverty is widespread.
b) General phrases, but the connotation of "bad thing" is in X, not the verb:
Weeds grow. (But kids grow, too.)
The debt increases/grows/rises/soars. (But profit rises, too.)
Bad news kept coming in. (But money can keep coming in, too.)
bonus) Some other phrases that's usually used when we have a lot or more of X and it's a bad thing. This is not strictly the case you seem to describe in your question, though:
Wars are everywhere.
Things worsen.
