ADAOBI TRICIA NWAUBANI and NITA BHALLA FOR eight years Nigerian housewife Mallama Baraka suffered in silence as the eye disease trachoma, which can blind but is entirely preventable, slowly took its toll. It started with a watery discharge and a burning, itchy sensation in her eyes. Her eyelids swelled and her eyelashes turned inside them, causing her extreme pain each time she blinked. Over time, she began to see less clearly. "It became hard for me to do my daily chores ... but the clinic is far and it would take time and money to go there. I thought whatever…