Shanghai and more than a dozen other cities in China are now under full or partial lockdown as the country faces its most significant spike of COVID-19 cases yet in the pandemic. But amid rapid increases in cases from the ultratransmissible omicron variant and China’s relatively low vaccination rate among its elderly, some experts are left scratching their heads over the lack of reported deaths.

In Shanghai, a city of around 26 million that functions as the country’s financial hub, residents’ patience has run out as they enter a second week of full, draconian lockdown. Videos have circulated online of people screaming from their apartments and berating officials over food shortages. There are reports of people being denied medical care and forced into crowded quarantine facilities. At the beginning of lockdowns, officials were widely criticized for separating parents from young children, including breastfeeding infants.

China reported more than 200,000 infections in Shanghai since the outbreak began last month. The vast majority of those are said to be mild or asymptomatic. So far, Chinese officials have reported that only one case in the city has been considered severe, and no deaths from COVID-19 have been reported.

That’s despite China failing to reach high levels of vaccination among its elderly population, who are the most at risk of severe disease and death from COVID-19. Only about half of people ages 80 and above in China have been fully vaccinated, and even fewer have received booster doses. Earlier this year, Hong Kong, which had similarly low vaccination rates among its older adults, saw an equally severe spike in omicron cases and recorded one of the highest daily death rates in the world.

In an interview Monday on CNBC’s Squawk Box, Scott Gottlieb, former US Food and Drug Administration commissioner and current Pfizer board member, expressed skepticism about China’s reported numbers. “It appears that they’ve lost control of this [outbreak] in Shanghai. There’s many more infections than what’s being reported,” he said. “The data coming out of there is implausible. They claim… only one severe case and no deaths—we know that’s not true.”

Gottlieb pointed to previous reporting from The Wall Street Journal and others of outbreaks in elder-care hospitals resulting in scores of fatalities. One hospital worker who spoke with the WSJ last month recalled seeing half a dozen hearses parked at the hospital’s gate at night. “I was scared to death. I said, ‘Look, look, those are for dead bodies,'” the worker told the newspaper. Shanghai has 4 million residents over 65, making its population one of the oldest in China, the WSJ noted.