What I would recommend is right now during winter, cut the vibs. down to the ground. They will grow back from root sprouts in the spring. Since the beetles lay their eggs at the branch ends, you may stand a chance of eliminating them. This is only if there are no wild stands of native vibernums nearby. If there are and they have been infected, all bets are off. Burn the branches you have cut down. This type of pest frustrates me. It is foreign as most of the worst pests are. They will continue to spread because nurseries will unwittingly or uncaringly sell infested stock far and wide. At a time when elms and chestnuts have disappeared, Maples are threatened by Asian Longhorns, Ash by Emerald Ashborer, Hemlocks by Adelgids, Oaks by Sudden Oak Wilt, Beeches by Cancker. What are our forests going to look like in a century. Where will diversity be? And for the most part these problems are the result of introduced pests on foreign plant stock. We are never happy with what grows around us, we need that Chinese Chestnut or Asiatic species of Vibernum. Ah enough preaching I guess.