You Do Need power plug adapter while traveling from Laos to Madagascar.

Here is Why You Need An Adapter

The outlet and plug type used in Madagascar are C and E and in Laos are A, B, C, E and F. This is how they look like.

Laos

In Laos, outlets of type A, B, C, E and F are in use.

Type A

Type B

Type C

Type E

Type F

Madagascar

In Madagascar, outlets of type C and E are in use.

Type C

Type E