Spanish has two words for ‘malaria,’ one of them being malaria itself, which English shares. That noun originated in Italian, and if translated directly into Spanish it would have come out *malaire, which is to say ‘bad air.’ People once thought that “bad air” caused the disease.
The other Spanish word for ‘malaria’ is paludismo, which English once shared in the form paludism. This term was based on Latin palus, with stem palud-, which meant ‘marsh, swamp’ and is the source of the uncommon Spanish noun palude that means ‘lagoon, pond, pool.’ The connection, of course, is that malaria-spreading mosquitos thrive in places with still, fresh water. From the same Latin word, English (but apparently not Spanish) has paludal and the less common paludine and paludinous, all of which mean ‘having to do with a swamp or marsh.’ Similarly, something ‘growing or living in swamps or marshes’ is paludose. Spanish palúdico can mean ‘having to do with swamps or marshes’ as well as ‘suffering from malaria.’
© 2019 Steven Schwartzman
Spanish-English Word Connections 
Jun 01, 2019 @ 10:47:29
Apparently the English ‘paludal’ and ‘paludine’ were first seen in England. I looked them up in the Oxford dictionary (which I rarely consult) and found that ‘paludian’ had its origin from mid 19th century and was found in ‘All the Year Round”, a Victorian periodical founded and owned by Charles Dickens and published between 1859 and 1895 throughout the United Kingdom. (https://en.oxforddictionaries.com/definition/paludian)
‘Paludine’ was found in mid 19th century; earliest use found in Francis Buckland (1826–1880), pisciculturist and naturalist. (https://en.oxforddictionaries.com/definition/paludine) Oxford dictionary states it may have originated from French ‘paludien’ or ‘paludéen’.
I much prefer the word ‘paludismo’ over ‘malaria’. I didn’t know there were English words that evolved differently from the Spanish.
Jun 01, 2019 @ 18:13:34
It’s interesting how many variants on the palud- root English developed. I don’t know why English needed so many of them. Sometimes Spanish and English share words, at other times not. Often that’s because English inherited words through French. Similarly, Spanish acquired a lot of words from Arabic that English doesn’t share.
Jun 01, 2019 @ 15:42:54
That’s an interesting distinction. Our salt marsh mosquitoes (Ochlerotatus sollicitans, or Aedes sollicitans) don’t carry malaria, but they could be described as ‘paludose.’ Everything that’s said about them in this article is exactly on target, especially this:
“Females of this species are aggressive biters, taking blood-meals from many kinds of animals including birds, reptiles, and mammals – especially humans. The species name sollicitans is Latin, meaning “vexing” or “disturbing.” They bite aggressively day or night, and even mosquitoes that are resting in the tall grasses by day will quickly take flight once disturbed and attack anyone walking thru the area.”
They certainly will. I’ve seen them in clouds so thick it’s hard to believe they’re mosquitos and not something more weighty, like love bugs.
Jun 01, 2019 @ 18:20:33
I’m a mosquito magnet, so anything that keeps their numbers down is just fine with me. The ‘vexing’ and ‘disturbing’ senses you mentioned come to the fore when we think about the “No Soliciting” signs that some people and businesses post. An online dictionary gives these translations for the Latin verb: ‘to disturb, stir, agitate, move; to distress, harass, make uneasy, vex, solicit, tempt, seduce, attract, induce.’