Appeal: A lonely Christmas for Jeremiah, living in a slum and separated from home

Nobody has been dreaming of a white Christmas in Kibera, least of all Jeremiah Govelo. Seasonal rains have turned Nairobi's mega-slum into a warren of treacherous muck trails. For Jeremiah, who lives at the bottom of one such alleyway, the colour of Christmas is definitely muddy brown.

Jeremiah returned from his work as a night watchman at dawn yesterday and flopped onto the bed of his tiny shack. It was another Christmas alone.

His wife and seven children are 250 miles away, at the family home in Vihiga. Jeremiah had already sent them money for Christmas – to buy rice, wheat flour and sugar – and that was all that mattered. "As long as I can provide for them, I am happy," he says.

There was no Christmas dinner for him – rather, a six-hour service at the Pentecostal Assemblies of God church, a quick nap and then back to work at 6pm, standing guard outside a restaurant. As usual, his employer provided dinner – maize meal and a few vegetables.

Kibera, Africa's second largest slum, is packed with people like Jeremiah. Several million Kenyans have left the countryside, where a swelling population has put unbearable pressure on available land, for the city, where they hope to find work. Most just find misery.

It is a pattern repeated all over Africa, indeed across the Third World. The phenomenon of urbanisation is one of the greatest – and least written about – scourges of the developing world.

The same thing happened in Europe, of course, during the Industrial Revolution. But Kibera makes the life of the poor in Britain in those days – the kind of thing portrayed in Dickens' less seasonal offering, Hard Times – look good by comparison. About 800,000 people are crammed into the sprawling sea of mud, tin and cardboard. Some live on top of rubbish heaps, others are squeezed by the edge of the railway line. One fifth of all children die before the age of five.

Every morning, thousands of men tramp across to the industrial area, in the often vain hope of finding day labour. Some men work as askaris – watchmen in city businesses or rich people's houses – while their wives may earn a little money as cooks or maids. But most do nothing at all, spawning a range of social problems – prostitution, crime, drug abuse, police harassment.

In short, Kibera seems like a place to run from, not flock towards. But for Kenyan peasants who want a better life for their children, there is no choice.

Jeremiah's deceased father left him only one quarter of an acre. The meagre patch could feed his children, but not buy clothes, pay hospital fees, or fund school tuition. Now he earns £20 for an 84-hour week, and one boy has reached Standard Seven. His eyes light up with pride. But his heart is still in Vihiga. "If I have enough space, I know I can be a good farmer," he says wistfully. It is but a dream.

The Kenyan government barely recognises the existence of Kibera, where one quarter of Nairobi's people live, and provides no services. Instead, the work falls to organisations such as Amref, one of three charities Independent readers are helping through our Hope for Africa appeal this Christmas.

Amref has concentrated its efforts in Laini Saba, a sub-village of 45,000 inhabitants. The medical centre provides basic healthcare, such as a four-bed maternity ward. Previously, if a pregnant woman developed complications her relatives would have to take her to hospital in a wheelbarrow, says Ruphine Oluoch, a nurse.

The Amref centre provides advice for clean home births, helps treat sick infants and gives a contraceptive injection for women who want to limit their family size. Some 20,000 people have benefited so far.

"This is a forgotten area," Ruphine says. "As far as the government is concerned, these people do not exist. But they are human beings, and they have rights."

It has also been a lonely holiday for Patricia Atieno. She came to Kibera more than 20 years ago with her husband, who was a cobbler. But he died of Aids three years ago. Their daughter, Jane, 25, followed shortly afterwards, leaving behind three children. Now Patricia is also dying.

"Christmas doesn't mean much to me," she says wearily, barely visible in the gloom of the room she shares with seven children. She was able to work last year, and so could provide a decent dinner. This year she can do nothing.

It would be nice to go home to Nyanza province. But Aids has robbed her of that back-up. After her husband's death, his relatives rejected her. "My brother-in-law chased me away. He said I was going to infect other people," she says.

Elections are being held in Kenya tomorrow, but Patricia hasn't been thinking much about the vote. "I haven't made up my mind. Anyway, I don't know if I will be alive," she says.

As well as helping Aids sufferers, Amref is tackling preventable disease through an initiative called Flying Toilets.

The chronic lack of latrines means many slum dwellers have to squat wherever they can – in a quiet corner, a nearby field, or even in the muddy streets. "Some people used plastic bags to relieve themselves, then would throw it over the wall. It could land anywhere – even on somebody's head," Reuben Kimweli, a community development worker, says.

Amref has already put up 50 new latrine and shower blocks, and has plans for a further 300. It's a small thing, but it can make a big difference. Just before Christmas, Lydia Mwaka, a hairdresser, was braiding a client's hair in her one-chair salon. Her family were sharing a new latrine with neighbours, and the results were already noticeable, she says. The children were getting sick less often.

"When the old latrine filled up it was disgusting," she says. "This new one has come to us like a blessing."