More than 16 million people in the region do not know where their next meal will come from and children are at risk of dying from starvation.
In South Sudan, Somalia, Kenya and Ethiopia, drought and conflict have left millions of people in immediate need of food, water and medical treatment.
Broadcasters raising awareness of the DEC appealThe DEC East Africa Crisis Appeal is launching today and will be shown on all major UK broadcasters including BBC, ITV, Channel 4, Channel 5 and Sky.
Money raised will support the efforts of DEC member charities, including HelpAge International partner Age International, to reach affected families and communities.
DEC Chief Executive Saleh Saeed said: "Hunger on a massive scale is looming across east Africa. More than 800,000 children under five are severely malnourished. Without urgent treatment, they are at risk of starving to death.
"We are hearing that families are so desperate for food that they are resorting to eating leaves to survive. This is something no family should have to endure.
"Unless we act now the number of deaths will drastically increase. Don’t delay – please donate."
DEC member charities are already on the ground delivering life-saving aid, such as food, treatment for malnutrition and clean drinking water.
They are ready to scale-up their humanitarian support, but they need more funding to reach the millions of people in urgent need.
Crisis in east Africa: how can you help?
You can donate through HelpAge's sister agency Age International.
You can also donate directly to the DEC East Africa Crisis Appeal:
- Text: Donate £5 by texting the word SUPPORT to 70000.
- Phone: Call the 24 hour hotline on 0370 60 60 610
- In person: Donate over the counter at any high street bank or post office, or send a cheque.
- Outside of the UK: Donate via HelpAge International.
The UK Government will match pound for pound the first £5 million donated by the public.
Stay up to date with developments in east Africa, the emergency response and the fundraising efforts by following the DEC on Twitter and Facebook. Contribute to the discussion using the hashtag #FightingFamine.