The night-time cold in New Delhi is biting. As the temperature plunges, Alam Ansari’s twin daughters, born prematurely, have only their parents’ body heat to keep them warm while they huddle in a crowded tent on the road outside the capital’s top hospital.

They are not alone. Each day, about 8,000 people from across the country queue outside the outpatients department for treatment. Mainly from poorer backgrounds, they sleep in tents or on the ground.

Ansari is rocking one of his three-month-old daughters. Something is wrong with both girls’ eyes, but he doesn’t know what. The family travelled to the All India Institute of Medical Science – known simply as AIIMS – after doctors in Bihar told them they were unable to offer treatment.

The train from their remote village to India’s capital took two days. A construction worker, Ansari borrowed 40,000 rupees. “That’s down to 5,000 rupees after being here two months. Every day we’re sent here and there, from one doctor to another. I don’t know what to do when my money runs out but I have to get my daughters well,” he says.

Amid the turmoil, the girls have yet to be named.

Alam Ansari and his wife, Seema, with their infant twin daughters outside the main hospital in New Delhi. Photograph: Amrit Dhillon

AIIMS runs a shelter for patients from out of town, but it is packed. Ansari and his family are lucky to have found space in one of the temporary tents erected outside by the Delhi government at the start of winter to give sick patients a place to wait for appointments, test results, and treatment.

Inside, more than 100 people are wrapped in multi-coloured blankets in the gloom. They are mostly two to a bed; many are very sick and weak, having inhabited tents or lived on pavements outside the hospital for weeks, if not months.

Millions of Indians find state hospitals are unable to help when they are seriously ill, leaving them no choice but to travel to New Delhi. AIIMS now operates in seven other states, but doctors at the hospitals outside New Delhi often lack specialist expertise. Patients are almost invariably referred to the capital.

The institute offers free consultations and some tests, although payment is still required for drugs.

Often, people who come for treatment cannot afford to rent a room. Waiting for an appointment or follow-up consultation is too expensive, travelling to and fro too exhausting.

So they stay on, sleeping, eating and living on the pavement, under trees and flyovers, in the metro subway, under bus shelters, and on the floor of public toilets.

Chandi Devi, who spent three weeks sleeping in the metro subway before finding space in a tent, looks exhausted and downcast. “My father needs both his knee joints replaced. He can’t walk. I have to ask others to help me take him to the toilet,” says Devi, who has left behind her three young children to bring her father to AIIMs. He remains silent throughout, his single nylon blanket offering scant protection from the daytime chill, much less the night.

Patients like Devi’s father get hot meals provided by NGOs. They use public toilets and buy bottled water. Clothes are washed and hung out to dry on the iron railings lining the busy road outside the hospital.

Space under a footbridge is much sought after. The more fortunate manage to get a bed in shelters run by charities and religious trusts, but need far exceeds supply.

“One day it’s go to this doctor, another day it’s go to another doctor. It’s endless. It’s been a month and they haven’t even started treatment because they say they haven’t got any beds,” says Devi.

In the next bed is a mother with her son. He looks about seven years old, but she says he is 18 and has a “growth problem”. Beside her are a couple with a daughter who has mental health problems.

Shalini and her husband Naresh, who is paralysed, have been living under a footbridge for six months. Photograph: Amrit Dhillon

Outside the tent, Shalini has been on the pavement for six months with her husband, who is paralysed. In the space under a footbridge, she has created a little “room” for her belongings, clothes and a few pots and pans.

Atul Sethi is here with her father. “His kidneys have failed,” she says, pointing to an emaciated figure on the ground, shrouded from head to toe in a white sheet. “He can’t stand. We came four days ago from Madhya Pradesh and are still waiting to see a doctor.”

Nearby, three-year-old Neelu, from a remote village in Jharkhand, is playing on the pavement by the government tents. Her “accommodation” is a makeshift bed erected on the road by her mother, Chunni Birhor. “I can’t sleep alongside so many people. The tent makes me feel claustrophobic, so I prefer to stay on the path with my daughter,” says Birhor.

Three-year-old Neelu, who has blood cancer, sleeps on a makeshift bed on the pavement. Photograph: Amrit Dhillon

Neelu smiles and scampers around. She looks healthy but Birhor says her daughter has blood cancer and will need to start treatment the moment a bed becomes available. Today is a good day. Often, Neelu doesn’t even feel like getting up.

Mother and daughter have been on the pavement for a fortnight. Neelu’s father, a mason from Madhopur in Uttar Pradesh, has gone to the chemist to buy his daughter some drugs. “We’re spending without earning. Every day is a day’s wages lost,” says Birhor, whose daughter is one of many children suffering from cancer who can be found outside AIIMS.

By 6pm it is dark and the temperature dips. It’s the rush hour and road next to the hospital is humming with traffic. The air is thick with smelly pollutants that sting the eyes.

Back at the tent, one of Ansari’s girls starts to cry. His wife takes her and starts to breastfeed. Even now, after two months living in a tent in the freezing cold trying to save the lives of his two infants,Ansari looks puzzled at his circumstances. “I thought that AIIMS, being the top hospital, would have made some ‘bandobast’ [arrangements]…”

Then he trailis off, sensing the futility of saying anything more.