In English, “worm” is a fairly general word, while “grub” refers to worms and insect larvae that eat fruit and some vegetables such as beans. “Maggot” refers to the worm-like larvae flies and beetles, which feed on decaying meat or flesh. The Hebrew words tole‘ah and tola‘ath are fairly general terms for worms of all kinds, regardless of what the worms eat.

In Exodus, Leviticus, and Numbers there occurs the phrase tola‘ath shani, literally “worm of scarlet”. The Hebrew name indicates both a scarlet color and the dye producing this color. The dye is made from the kermes insect Coccus ilicis, which was found in the Ararat region. The dye was traded by the Phoenicians, who carried it to the Middle East, North Africa, southern Europe, Mesopotamia, and even further.

Unlike the more general words tole‘ah and tola‘ath, rimah and its Greek equivalent skōlēx refer exclusively in the Bible to flesh-eating worms, in other words, maggots. The use of “worm” and “vermin” in modern English versions is motivated by the fact that to say that one’s own body is covered with maggots is repulsive and impolite in English culture. It may not be in other cultures.

Worms, grubs, and maggots are small, soft, legless, tube-shaped creatures that have no bones or shells. They typically feed on overripe fruit, rotting meat, and similar things. Most are actually larvae that hatch from the eggs laid by flies or some beetles. Most of them mature into pupae and then into adult forms of the parent insects.

In the Bible worms and maggots are symbols of uncleanness, decay and insignificance. In Psalms 22:6 and Isaiah 41:14 the word tola‘ath signifies a very insignificant human being or even nation. Where comparing a person with a worm or maggot will not convey the same meaning, it may be possible to find some other insect which symbolizes insignificance. Where no such comparison exists, it will be necessary to follow something like “weak and helpless as a worm.”

Maggots were a symbol of uncleanness, decay, and death. In Job 25:6 the maggot is symbolic of a repulsive, insignificant person.

Worms and maggots are found universally, and finding equivalents should not be too hard. However, in many languages there are specific words for different kinds of worms or maggots, but no generic word that includes them all. In such cases the individual contexts should guide the translator. When the reference is to worms destroying grapes or olives, a suitable word for such a context should be found; when the reference is to maggots that feed on corpses, a suitable word for these contexts should be used. It is more important to translate appropriately for a given context than it is to translate one Hebrew or Greek word the same way every time.

The use of a word for a flesh-eating worm or maggot is appropriate for all contexts.

Source: All Creatures Great and Small: Living things in the Bible (UBS Helps for Translators)