It is believed that these individuals became sick as a result of intentional aerial spraying with pesticide, after they refused to vacate their ancestral lands. Governmental officials confirm that parts of the indigenous group's land located in the Itakyry district in the Department of Alto Paraná had been sprayed where no crops are present . 
Watendaji wa serikali wamethibitisha kwamba baadhi ya sehemu za ardhi ya wenyeji iliyo katika Wilaya ya Itakyry katika Idara ya Alto Paraná ilinyunyiziwa wakati ambapo hakukuwa na mazao yoyote .