As the Chinese authorities confront scattered coronavirus outbreaks in the country’s northeast, they are turning to many of the same strict lockdown measures that they used this winter in the central city of Wuhan. The measures take effect as China prepares for the biggest event on its political calendar, the annual session of the National People’s Congress — a tightly choreographed legislative pageant aimed at conveying the strength of the ruling Communist Party. The response reflects fears among China’s leaders over the potential for a fresh wave of infections as factories, schools and restaurants reopen across much of the country.

President Xi Jinping has seized on the pandemic as a chance to redeem the party after early mistakes let infections slip out of control and to rally national pride in the face of international ire over those missteps. That theme is likely to underpin the National People’s Congress, an annual legislative meeting that opens on Friday after a monthslong delay. Mr. Xi has largely succeeded in rewriting the narrative in China, in part because the disarray in other countries, especially the United States, has given him a reprieve from domestic political pressure.

But keeping up that narrative may be challenging. He must continue to push his agenda while China faces a diplomatic and economic climate as daunting as any since the Tiananmen Square crackdown in 1989. And the country faces growing criticism around the world for its early attempts to conceal the outbreak in Wuhan. “If you position yourself as a great helmsman uniquely capable of leading your country, that has a lot of domestic political risk if you fail to handle the job appropriately,” said Carl Minzner, a professor of Chinese law and politics at Fordham University.