Two doses of oral ivermectin administered throughout the population is better at dealing with outbreaks of scabies than mass treatment with permethrin, an Australian study shows.

The mass treatment was tried across three of Fiji’s island communities, each of which received a different regimen to try to eliminate the microscopic mites that cause the contagious, itchy skin condition.

In all, 823 people were evaluated for the two-year follow-up. More than 85% of the 2403 people on the three islands enrolled in the baseline sample for the study, known as SHIFT, the authors report in the New England Journal of Medicine.

After two years, the prevalence of scabies had dropped from 32% to 3.6% with oral ivermectin, from 42% to 13.5% with topical permethrin given to everyone, and from 37% to 15.2% when permethrin administration was restricted to infected people and their contacts.