Gulper pump helps Tanzania's sewage problem
Only 10% of Dar es Salaam, Tanzania's biggest city, is connected to the central sewage system.
The pit latrines often overfill and emptying them is infrequent, dangerous and unhygienic.
Water Aid is pioneering a cheap simple pump and motorbike device that empties up to six latrines a day and is helping to reduce diseases such as cholera and typhoid.
The Health Show is broadcast on Saturdays at 1010 and 2010 GMT and on Sundays at 0710 and 2310 GMT. The programme is supported by the Gates Foundation.