The crisis has engulfed the drought-prone region of the Sahel, where four of the world's poorest countries have been affected: Niger, Mali, Mauritania and Burkina Faso. Niger is the worst affected with up to 2.5 million of its 12 million population estimated to be at risk of severe hunger.
The crisis has been developing since last August when a massive locust invasion swept the area during the growing season and destroyed the harvest. This combined with severe drought has left the population with little food.
The Sahel has been affected by food security problems for several decades. The region first came to the world's attention in the early 1970s when severe drought led to a very serious food security crisis and a major humanitarian response.
This is an area of the world characterized by chronic extreme poverty and very high levels of vulnerability.
This period of the year is always difficult in the Sahel. This is the lean period or "soudure" when the harvest from the previous year has been exhausted and the current season's production is not yet available. The length of this period depends on the quantity of the previous year's production.
Distribution of free or subsidised food in some areas of Mali and Burkina Faso has limited the impact of food shortages in these countries.
Niger is the second poorest country in the world. Six in ten of Nigeriens live on less than US$1 a day. The country has the second highest under-five mortality rate in the world (263/1,000 live births). One in four children die before their fifth birthday. Only 48 per cent of the population has access to primary health care.
In March cereal prices in Niger were 46 per cent higher than at this time in 2003. Many people have moved out of rural areas in Niger to urban centres in search of food and employment.
This is said to be Niger's worst food security crisis since 1984. Several years of particularly severe economic hardship in Niger have reduced people's capacity to cope with shocks. The situation is particularly bad for pastoral communities.
Only around 15 per cent of land in Niger is suitable for agriculture. Even in years of relative normality in Niger, around 40 per cent (one million) of children suffer from some degree of malnutrition.
Nutritional surveys in Niger indicate a severe acute malnutrition rate of around 2.4 per cent - 2.9 per cent amongst children under-five. The global malnutrition rate is around 20 per cent. In the most seriously affected areas severe acute malnutrition is as high as 13.4 per cent (UNICEF). It is feared one in ten children could die unless they get urgent help. Present estimates for Niger are that 350,000 children suffer from acute malnutrition, of which 63,000 could be severe cases.
Compared to Niger, Mali, Burkina Faso and Mauritania are not as badly affected by the food crisis but are reaching an alarming situation.
Around 20 per cent of the Mali population is affected by the food shortage. (Population circa.11 million)
Animal carcasses litter the hardest hit areas, including cattle, horses and donkeys.
An estimated 750,000 or 26 per cent of the population is affected. (Population of nearly three million)
Mauritania suffered three years of drought until 2004 when the rains came but with them came the Sahel region's worst invasion of locusts in 20 years. The locusts infested every corner of Mauritania's agricultural zone, munching their way through the cereal and other crops that are the lifeblood of the rural poor. Studies by WFP (World Food Programme) show that six out of 10 families in the agro-pastoral zone will not have enough to eat in 2005.
500,000 people left vulnerable out of a population of more than 13 million.