Better photos of specific areas will probably be more helpful.
Morse code and green J-hooks
U of H 2006
Banana Bunchy Top Disease in Hawaii: Symptoms, Diagnosis and Management
U of H 2004
U of H 1997
Symptoms of BBTV
The initial symptoms of banana bunchy top virus consist
of dark green streaks in the veins of lower portions
of the leaf midrib and the leaf stem (petiole) (Figure 1).
The streaks also occur, but are less prominent, in the
veins of the leaf blade (lamina). This symptom is sometimes
referred to as “Morse code streaking” because the
streaks are irregular and resemble a series of “dots” and
“dashes.” Rubbing away the waxy white coating that
covers the petiole or midrib makes it easier to see the
streaking. Also, dark green, hook-like extensions of the
leaf lamina veins can be seen in the narrow, light-green
zone between the midrib and the lamina (Figure 2). The
short hooks point down along the midrib toward the
petiole. They can best be seen by back-lighting the leaf
against the sky.