Garbage is seen piled up on a street during a strike by garbage collectors demanding delayed salaries in Sanaa, Yemen May 8, 2017. REUTERS/Khaled Abdullah - RTS15NJ4
A boy infected with cholera lies on the ground at a hospital in Sanaa, Yemen May 7, 2017. Picture taken May 7, 2017. REUTERS/Khaled Abdullah - RTS15OBH
Relatives sit next to a sick man waiting to be admitted to a hospital in Sanaa, Yemen May 6, 2017. Picture taken May 6, 2017. REUTERS/Khaled Abdullah - RTS15OCZ
Women walk past a pile of rubbish bags on a street during a strike by garbage collectors demanding delayed salaries in Sanaa, Yemen May 8, 2017. REUTERS/Khaled Abdullah TPX IMAGES OF THE DAY - RTS15QZ0
A boy collects recyclable materials from a pile of rubbish bags on a street during a strike by garbage collectors demanding delayed salaries in Sanaa, Yemen May 8, 2017. REUTERS/Khaled Abdullah - RTS15NJY
A girl infected with cholera lies on the ground at a hospital in Sanaa, Yemen May 7, 2017. Picture taken May 7, 2017. REUTERS/Khaled Abdullah TPX IMAGES OF THE DAY - RTS15OBI
A cholera-infected man reacts as he lies on a hospital bed in Sanaa, Yemen May 6, 2017. Picture taken May 6, 2017. REUTERS/Khaled Abdullah - RTS15OD0
A man covers his nose as he walks past a pile of rubbish bags on a street during a strike by garbage collectors demanding delayed salaries in Sanaa, Yemen May 8, 2017. REUTERS/Khaled Abdullah - RTS15NJZ
A man sits as he waits for a cholera-infected relative at a hospital in Sanaa, Yemen May 6, 2017. Picture taken May 6, 2017. REUTERS/Khaled Abdullah - RTS15OCY
A girl pushes a wheel cart with water jerrycans past a pile of rubbish bags on a street during a strike by garbage collectors demanding delayed salaries in Sanaa, Yemen May 8, 2017. REUTERS/Khaled Abdullah - RTS15OET
Women walk past a pile of rubbish bags on a street during a strike by garbage collectors demanding delayed salaries in Sanaa, Yemen May 8, 2017. REUTERS/Khaled Abdullah - RTS15NJ9
A girl infected with cholera lies on the ground at a hospital in Sanaa, Yemen May 7, 2017. Picture taken May 7, 2017. REUTERS/Khaled Abdullah - RTS15OBJ
A cholera-infected woman lies on a hospital bed in Sanaa, Yemen May 6, 2017. Picture taken May 6, 2017. REUTERS/Khaled Abdullah - RTS15OD2
A boy collects recyclable materials from a pile of rubbish bags on a street during a strike by garbage collectors demanding delayed salaries in Sanaa, Yemen May 8, 2017. REUTERS/Khaled Abdullah - RTS15NK0
A girl infected with cholera sits on a chair at a hospital in Sanaa, Yemen May 7, 2017. Picture taken May 7, 2017. REUTERS/Khaled Abdullah - RTS15OBN
A boy and his mother, both infected with cholera, lie on a bed at a hospital in Sanaa, Yemen May 7, 2017. Picture taken May 7, 2017. REUTERS/Khaled Abdullah - RTS15OBE
Women help a young relative infected with cholera at a hospital in Sanaa, Yemen May 7, 2017. Picture taken May 7, 2017. REUTERS/Khaled Abdullah - RTS15OBL
Rubbish bags pile up on a street during a strike by garbage collectors demanding delayed salaries in Sanaa, Yemen May 8, 2017. REUTERS/Khaled Abdullah - RTS15OEH
Yemen's trash mountains add to war woes
Women walk past a pile of rubbish bags on a street during a strike by garbage collectors demanding delayed salaries in Sanaa, Yemen May 8, 2017.