Barbara...have not heard. This is a normal-fault earthquake, so there could be some vertical motion of the Lake floor...and this could cause what you suggest. I went down the length of Lake Tanginyika, in 1985, in a steamer built in the 19-teens...I think the parts were built in Germany and then put on the train to bring it to the Lake...where it was assembled. We were on our way to Malawi to study rift faults. At the time, and probably today, the ship was met by a lot of dugout canoes at stops. This is probably the largest east African rift earthquake in some years....The lake can be very deep in places...by very, 700 m rings a bell, but that may be Lake Malawi...which is similar.

One other hazard is that tropical lakes do not overturn seasonally, so can have buildups of gases (like CO2) in the bottoms of the lake...or, at the least, the bottom water are probably very poor in oxygen. An earthquake this size could, at the least, bring these oxygen-poor waters to the surface and cause massive fish-kills....which farther down the road would lead to (more) malnutrition in people.
Chris

• Tanganyika quake