“The last time I had a good harvest was 2003 — there has been nothing at all for the last three years,” said Mutindi Maithya, 36, a widow who lives with her six children on a four- acre plot of sun-baked land.

Sitting beneath a thorny acacia tree, she picks up ochre lumps of dried mud from the ground and crushes them to dust between her fingers. “It is hard to cope,” she said.

A four-year drought has pushed as many as 23 million people to the brink of starvation across East Africa, making it the worst in a decade or more. Close to four million of those at risk are in Kenya, where one person in ten survives on emergency rations.

Last week clouds gathered over much of the country, but the rains have come too late to bring much relief. Aid agencies have warned that with them will come flooding, cholera, malaria and hypothermia.

In the arid north, pastoralists have watched as their cattle collapsed from exhaustion and thirst, and those that survive now face floods. The people are scarcely holding on and the number of armed skirmishes over water and livestock is rising.

Even in usually greener regions the drought has taken its toll. Four consecutive harvests have failed in the southeast while the Rift Valley, Kenya’s breadbasket, is a wasteland of withered crops. There are fears that heavy rains will wash away the topsoil, taking with it precious maize seeds.

In Nairobi emaciated cattle led by desperate Masai herdsmen graze by the roadside. The economy is also threatened by plummeting tea and coffee production, while tourists who visit the country’s money-spinning safari parks return with tales of landscapes littered with carcasses.

Drought is nothing new to this part of Africa, but what is different is the frequency with which it hits. The cycle of drought used to come around every ten years but now it is almost constant. Many attribute the changing patterns to climate change.

Kenya’s fractious coalition Government, forced together last year after a violent election, has been accused of hindering rather than helping the situation by failing to safeguard the country’s strategic grain reserve.

Even as the current disaster loomed, thousands of sacks of maize went missing earlier this year. Some reappeared later in neighbouring Sudan. Dark accusations circulated that it was the work of certain politicians in cahoots with favoured traders.

In Mwingi people scrape a living from the land by farming small fields and keeping livestock. Harvest after harvest has failed, livestock has perished and wells have dried up.

“For the last four years these farmers have held on to hope, but each year been left with despair as the rains failed,” said Fergus Conmee, Africa humanitarian manager for the Catholic aid agency Cafod. “This humanitarian crisis has pushed them on to a tightrope of survival and many farming families have been left destitute.”

Mafuo David, 36, is one of 3,500 people in the area receiving emergency supplies of maize, beans and oil from Cafod. Most days she manages to feed herself and her family two meals, but the first of these is usually black tea with sugar and the second a bowl of maize.

She said that in a good year she used to harvest five bags of maize and three of beans but it had been a long time — “maybe ten years” — since such a bumper crop. Last year everything died, and the year before she harvested two bags of maize and beans; the year before that, nothing.

Her husband died of an Aids-related illness in 2001 so she tends the three-acre family plot with the help of her eldest son. The light drizzle this week made her smile: “The land has changed, we have soft soil to plant in and water to drink. Even our bodies are changing; our faces are shining.” Ms David has felt this optimism before, and been disappointed.

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