A man sleeps as he waits in a queue to collect a token to receive a dose of COVISHIELD vaccine, manufactured by Serum Institute of India, outside a vaccination centre in Siliguri, in the eastern state of West Bengal, India, October 6, 2021. Residents of a city in northeast India are spending nights in snaking queues outside vaccination centres awaiting their turn for a COVID-19 shot, an anomaly in a country with a surplus of vaccines. REUTERS/Rupak De Chowdhuri

Women play a game of ludo as they wait to receive a token to receive a dose of COVISHIELD vaccine, manufactured by Serum Institute of India, outside a vaccination centre in Siliguri, in the eastern state of West Bengal, India, October 7, 2021. In Siliguri, a city in West Bengal state close to India's border with Bangladesh, local police sometimes have to be brought in to control unruly crowds of people gathered outside vaccination centres. REUTERS/Rupak De Chowdhuri

A security official checks the identification papers of people waiting in a queue to receive a dose of COVISHIELD, a coronavirus disease vaccine, outside a vaccination centre in Siliguri, in the eastern state of West Bengal, India, October 6, 2021. The modest size of vaccination centres and a shortage of staff account for some of the queues, two local officials who declined to be named told Reuters. REUTERS/Rupak De Chowdhuri

People wait in a queue to receive a dose of COVISHIELD vaccine, manufactured by Serum Institute of India, outside a vaccination centre in Siliguri, in the eastern state of West Bengal, India, October 7, 2021. REUTERS/Rupak De Chowdhuri

People stand in a queue to receive a dose of COVISHIELD vaccine, manufactured by Serum Institute of India, outside a vaccination centre in Siliguri in the eastern state of West Bengal, India, October 7, 2021. REUTERS/Rupak De Chowdhuri

A woman receives a dose of COVISHIELD, a coronavirus disease vaccine manufactured by Serum Institute of India, at a vaccination centre in Siliguri, in the eastern state of West Bengal, India, October 7, 2021. REUTERS/Rupak De Chowdhuri