NEW DELHI (AP) — India is experiencing its worst pandemic surge, with average daily infections exceeding 143,000 over the past week. The spike is particularly alarming because India is a major vaccine producer and a critical supplier to the U.N.-backed initiative that aims to help distribute shots fairly. Already the rise in cases has forced India to focus on satisfying its domestic demand — and delay deliveries. When infections began plummeting in India in September, many concluded the worst had passed. Masks and social distancing were abandoned, while the government gave mixed signals about the level of risk. When cases began rising again in February, authorities were left scrambling.