They may be aphids or some other type of insect with piercing sucking mouthparts. There are sprays that are effective but when the leaf curls you cannot get a spray inside where the insects are. Thus a systemic product may be the best option. Products containing Disyston or Imidacloprid are some possible options. Check the labels to make sure the product you are choosing is labeled for ficus or houseplants and follow label directions carefully.
An even better option is to take some leaves showing the insects and their damage to your County Extension Office (The following website give their contact info: http://pasco.ifas.ufl.edu/office_locations.htm) and see if they can identify the cause of the damage. They would then be able to recommend an appropriate, labeled insecticide product for you to use.
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