> despite almost 2 decades of smart and good people working hard

Longer than that, by far. Roger Morse was on the job as early as 1968:

> Two species of mite infest colonies of Apis mellifera in the Philippines: Varroa jacobsoni and Tropilaelaps clareae (Laigo & Morse, 1968). We did not find any colonies of Apis mellifera in the Philippines that were not infested with one or both species
of mite.

> Colonies from which we collected several hundred V. jacobsoni had several adult bees which were stunted; some of these, and some others, had deformed wings; the bees soon removed deformed individuals from the hive. However, most of the affected bees died in the pupal stage.

> We treated several colonies of A. mellifera with chlorobenzilate, both the commercial Folbex preparation and a similar preparation made in our own laboratory. After these treatments we collected large numbers of mites, but none of six colonies given one treatment a week for 12 weeks ever became free from mites.

R. A. Morse & F. M. Laigo (1969) The Potential and Problems of Beekeeping In the Philippines, Bee World, 50:1, 9-14, DOI: 10.1080/0005772X.1969.11097235

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