Are "dual sensory impairment" and "deafblindness" the same thing?

Deafblind International

The term deafblindness describes a condition that combines in varying degrees both hearing and visual impairment. Two sensory impairments multiply and intensify the impact of each other creating a severe disability which is different and unique. All people who are deafblind experience problems with communication, access to information and mobility. However, their specific needs vary enormously according to age, onset and type of deafblindness. People who are deafblind are unable to use one sense to fully compensate for the impairment of the other. Thus they will require services which are different from those designed exclusively for either people who are blind or people who are deaf.