U.S. Virgin Islands and Guam 
The U.S. Virgin Islands of St. Croix, St. Thomas, and St. John remain 
tick-infested and under Federal quarantine. The Island of Guam is also 
under Federal quarantine. 
Ticks collected from cattle on St. Croix were identified on September |, 
1967, as Amblyomma variegatum (tropical bont tick). This was the first 
evidence that the tropical bont tick might establish itself on U.S. terri- 
tory. This tick is an important pest in many areas of the world and can 
serve as a vector of diseases affecting animals and man. The tick is a 
three-host tick with a very broad host range. Generally, the adult tick 
feeds on larger animals; and the larval and the nymphal stages feed on 
smaller animals such as cane rats, ground squirrels, and mongooses. 
A program was immediately undertaken to prevent further spread of the tick 
on the island, and an eradication program was quickly developed. All live- 
stock on the island were immediately inspected. Later a second inspection 
was made, and in June 1969 all livestock were inspected again. The infesta- 
tion was found to be limited to six contiguous premises involving some 
2,600 acres. A. variegatum ticks were collected from cattle, sheep, goats, 
dogs, horses, and mongooses. 
The A. variegatum eradication program on St. Croix included insular quaran- 
tines on the infested premises, dipping all livestock at 7-day intervals 
(changed to |4-day intervals in August 1968) in 0.125 percent coumaphos 
(Co-Ral) and spraying infested premises with 2 pounds of active ingredient 
carbaryl (Sevin) per acre. 
The aerial spraying was planned and conducted by Special Operations Force, 
U.S. Department of the Air Force, Eglin Air Force Base, Florida. Sevin 
was sprayed from jeeps carrying the spraying equipment or from aircraft, 
depending on terrain. Spraying was completed In December 1968. 
The last collection of A. variegatum from livestock on a farm had been in 
April 1968. The survey of St. Croix in May 1969 revealed no A. variegatum 
ticks, and overall results were encouraging. However, on August 7, 1969, 
a single male tick was found at the slaughterhouse on a bull from the 
eastern part of the island; the six previously infested premises were on 
the western end. Inspections of livestock on the farm of origin of the 
bull and on other farms in that area did not disclose any additional 
A. variegatum ticks. 
Systematic dipping was discontinued on each farm 2 years following the most 
recent collection of A. variegatum on the farm, and thus all systematic 
dipping was discontinued in May 1970. In May 1970, a complete inspection 
of livestock on St. Croix was made and no A. variegatum ticks were found. 
On March I|7, 1971, a Consumer and Marketing Service (C&MS) meat inspector 
collected a male A. variegatum tick from a sheep at the local abattoir. 
