The most common and most likely answer to this crossword clue is the 8 letter word LISTERIA
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More clues leading to the result LISTERIA
- It is real nasty
- Threat to health, minute one found in time
- Incline, with age, to catch one disease
- Schedule time to get to grips with one source of food poisoning
- Disease realist treated with injection of iodine
- Bacterium found in roll – a type of killer is uncovered
- Infectious bugs in river coming up under log
- Bug is real, it spreads
- A threat to health — it is real unfortunately
- Complaint of reformed Blairites having ousted their leader
Buddy explains!

The straight part
We know that "sample of bacterium" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case sample of bacterium = listeria.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 LISTERIA mean?
LISTERIA noun- Any rod-shaped, gram-positive bacterium, of the genus Listeria, especially those responsible for the bacterial infection listeriosis.