Brazil's battle against Rhipicephalus (Boophilus) microplus ticks: current strategies and future directions.

Ticks are parasitic arthropods that cause significant economic losses to livestock production worldwide. Although Rhipicephalus (Boophilus) microplus, the cattle tick, occurs throughout the Brazilian territory, there is no official program to control this tick, which is the vector of tick fever pathogens. We address the situation of R. (B.) microplus resistance to synthetic acaricides in Brazil, including cattle tick management; the status of tick resistance per Brazilian state; the history of resistance occurrence of different acaricides; multiple resistance occurrence; and the main strategies for integrated tick management. Tick control in Brazil is characterized by management errors. Local laboratories affiliated with federal and state research institutions and universities employ the Adult Immersion Test as a primary diagnostic method to assess acaricide resistance to topically applied drugs. Only three states (Acre, Amapá, and Amazonas) have no reports on resistant populations. Misinformation on tick control strategies, misuse of available products for tick control, no adoption of Integrated Parasite Management (IPM) practices, low technical support to producers, and the high-speed emergence of acaricide-resistant tick populations are the main problems. We also propose a list of needs and priorities for cattle tick control regarding communication, research, and policies.