Neumann (1899) is credited for the identification of A. cajennense from Trinidad. Nuttall et al. (1926) mentioned that A. cajennense, a common tick species in the West Indies and Central and South America, was often a troublesome pest at certain seasons of the year, when the larvae swarm in thousands in the grass and herbage and attack both man and domestic animals with avidity. Aitken et al. (1958) recorded ’The 1958 Cayenne tick outbreak’ at the Lagoon Doux Estate, south of Mayaro, where only the labourers showed serious effects of tick exposure, such as bout and skin irritations. These authors found A. cajennense on a variety of animals including man. Spraying dichlorodiphenyltrichloroethane (DDT), Gamma Benzene Hexachloride (GBH), chlordane and dieldrin helped to control the tick population. Smith (1973) found very large populations of A. cajennense ticks in infested areas with uncontrolled grass growth and suggested that a reduction in grass length and the removal of tree shade could help reduce the tick populations. He also studied the distribution of A. cajennense in Trinidad and Tobago; this tick was found only in Trinidad on the Cedros peninsula and on east coast at Mayaro. Smith (1974) recorded A. cajennense in ruminants, equines, dogs and man. The ecology and life cycle of this tick was also investigated by Dindial (1977) and Smith (1975), respectively. Dindial (1977) found that A. cajennense was present in the coastal regions of Manzanilla, Mayaro, Guayaguauare and the Cedros Peninsula area of Trinidad and was absent in Tobago. The presence of A. cajennense on cattle was also established by Clarkson (1969) and Rawlins (1977) in Trinidad. Lans (2002) reported a second outbreak of this tick from 1994 to 1996 in Cedros and Mayaro linked to the presence of free-ranging cattle on the coconut estates.

Amblyomma cajennense is known to transmit Wad Medani in Jamaica and Rickettsia rickettsii (Rocky Mountain Spotted Fever) (Jongejan and Uilenberg 2004).

Distribution: ranges from southern USA to northern Argentina and Caribbean Islands (Cruz 2001; Voltzit 2007).