There are those who feel sympathy for any living creature. There are those who espouse a non-human-centric philosophy of existence, some of whom view the elimination of other classes of organisms either neutrally or negatively. There are those who are hostile in varying degrees to the population afflicted by the guinea worm and who, disconnected from their suffering, are ambivalent about the cessation of that suffering.
Any individual in those groups might change their perspective if the guinea worm's menace were made more tangible to them — if they or those close to them were infected, or perhaps if they were to witness the suffering of the afflicted up close. But the range of human emotion and ideology is vast.