David Zulou is suffering from advanced vitamin deficiency, known as kwashiorkor.

His little sister Sorigina is one-and-a-half. She suckles the breast of her mother Lucia, but breast milk is not sufficient for her and there is little to be had.

Lucia's husband went away to look for work, leaving his wife and children with his brother, a tenant farmer on a tobacco estate.

In normal times, the tenants are given maize through the growing season on credit against their tobacco crop.

But this year, the price of tobacco is low - as little as one seventh of its usual value - and the price of maize has been high - up to three times the usual price.

The result is the cost of maize to the landlord cannot be recovered from the sale of the tobacco, so the landlord has simply ceased to provide food for the tenant farmers, who are now going hungry.

Lucia's brother-in-law had little enough for his own family and was unable also to feed hers.

So there was nothing for Lucia, David and Sorigina.

Lucia watched as both her children became sick from malnutrition and when David's condition worsened they all walked over 50 miles from their village to the Kasungu District Hospital.

They are recovering now in hospital, but the future is bleak.

"When the children are better, we will go to my home village near Lilongwe and hope to survive there," says Lucia, but with shortages everywhere and 10 months, until the next harvest her prospects are poor.

UNICEF is providing food and specialised therapeutic feeding for the most vulnerable women and children like David and his family, and is urgently looking for funds to set up much needed medical centres around Malawi and the entire region.