I think thr vulnerable people face Effect as a consumer and producer.

As a consumer, people cannot continue their job or may be kicked out from job or may be enforced to received half/Lower salary. It further reduce the aggregate demand. Or unemployed people cannot manage job, that show similar effect. So thay will face higher prices in THE market . That reduce the purchasing power of money and creates hunger.

As producer, due to lower aggregate demand, the price level will fall. Lower income will bring the similar fate for producer As like As consumer.

I guess you may find your answer here.

https://www.un.org/development/desa/dspd/everyone-included-covid-19.html

Please refer this. It might be helpful

https://www.brookings.edu/blog/future-development/2020/05/06/turning-back-the-poverty-clock-how-will-covid-19-impact-the-worlds-poorest-people/