The most common and most likely answer to this crossword clue is the 7 letter word MEASLES
M
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More clues leading to the result MEASLES
- Disease sees lamb mostly destroyed
- Complaint from setter before son gets in beers
- Use extract of thyme as lessening for fever
- Micawber getting terrible sales fever
- Spots this person playing the part of Dawson
- Disease that could create lameness, knocking out any number
- Some rash German, perhaps
- Medical complaint, chronic fatigue syndrome, affected sales
- Spots infection
- Fevered Al seems to have spots
Buddy explains!

The straight part
We know that "Viral disease" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case viral disease = measles.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does MEASLES mean?
MEASLES noun- Rubeola, an acute highly contagious disease, often of childhood, caused by Measles virus, of genus Morbillivirus, featuring a spreading red skin rash, fever, runny nose, cough and red eyes
- Any of several other similar diseases, such as German measles.
- A disease of pigs and cattle, caused by larval tapeworms.
- A disease of trees, in which the leaves are covered in spots.
- A leper.
- A tapeworm larva.