Most cultivated plantains are interspecific cultivars or hybrids: they harbour Musa acuminata (A) genomes and Musa balbisiana (B) genomes which hosts infectious endogenous Banana streak virus sequences (eBSVs). Spontaneous infections can arise in plantains following activation of these sequences by biotic and abiotic stresses, such as tissue culture and temperature differences, while several mealybug species can transmit BSV horizontally. The level of activation of infectious eBSVs by tissue culture has been quantified for several plantain cultivars and hybrids [1, 2], but virtually nothing is known about activation levels under field conditions, thus preventing the assessment of the risk of spreading BSV through large scale cultivation of plantains. This question was addressed in the Dominican Republic, using the most widely cultivated plantain types in the country: triploid AAB cultivar Macho x Hembra (MxH) and tetraploid AAAB hybrid FHIA21. Both carry infectious eBSV alleles OL1 and GF7 of the two distinct BSV species BSOLV and BSGFV, respectively, but are devoid of infectious eBSVs of species BSIMV. Firstly, a nationwide survey was conducted throughout all Dominican banana growing areas. A total of 590 leaf samples of FHIA21 and MxH were collected from 36 locations reflecting the diversity of banana cultivation conditions in the country (temperature, irrigation, type of planting material, presence of mealybugs...). Samples were indexed for viral species BSOLV, BSGFV and BSIMV. Based on these results, two locations were selected for an in depth survey: 100 FHIA21 and 100 MxH leaf samples were collected from nearby plots in each location, and mealybug samples were also collected on sampled plants. All plant samples were indexed for viral species BSOLV, BSGFV and BSIMV, whereas total DNA was extracted from mealybugs and used to type mealybug species and search for BSV in mealybugs. Results from indexings and molecular analyses were used in a multifactorial statisti