To avoid long queues at vaccination centres, the public could log on to the website, gccvaccine.in, to book their slots by selecting their corporation zones and the centres. “Apart from the website, the people can also call on 044-4612 2300 and contact on 9499933544 through WhatsApp to book a slot. This will help avoid long waiting time and overcrowding at the vaccination centres,” an official release of the Greater Chennai Corporation said.