Cholera, typhoid and diarrhoea will be the major threats facing the hundreds of thousands of survivors of the tsunami, the WHO's head of communicable diseases in complex emergencies has warned.
From her family home in Galway, Dr Máire Connolly told The Irish Times yesterday the big challenge was the huge geographical area affected by the disaster, and the "all at once" nature of it.
"Five million people are at risk of disease," she said. "In terms of natural disasters and the numbers affected, this is the biggest operation the WHO has faced.
"The main immediate issue is the lack of safe water and access to medical care. In the next two to three weeks the dangers will be the mosquito-borne diseases - malaria and dengue fever."
Diarrhoea, vomiting, typhoid and cholera are all risks where there is a lack of safe water. The former two can be fatal, particularly for children and the elderly, while cholera and typhoid are both highly-contagious.
Dr Connolly, who studied medicine in Galway and joined the WHO in 1995, said its immediate priority was to get early-warning systems up-and-running, in conjunction with the health services already in the countries.
"We will draw up a list of eight to 10 priority diseases with the health clinics and agree that if they have five or more cases of say cholera, typhoid, measles or jaundice, a central team will be notified and a network of back-up rapid-response teams will be responsible for getting in fast, isolating the cases, administering intravenous fluids and medication to mop up the outbreak immediately, to make it as much as possible a non-issue. The big challenge is getting to each local health centre."
"Eleven countries are affected, though the four worst are Sri Lanka, Indonesia, Thailand and India. Probably the worst-affected and at risk of disease is Indonesia."
While she has been involved in communicable disease-control programmes in war situations such as Yugoslavia, East Timor, Afghanistan and Sudan "in this situation it is so sudden, so geographically vast and so all-at-once".
She is cautiously optimistic however, saying weekend predictions that greater numbers would die of disease than were killed by the tsunami "are the worst-case scenario".
"I think if we get the early-warning response in place and with proper water chlorination, we can control outbreaks. These governments are actually used to dealing with emergencies. They deal with monsoons every year and they and their armies are working very, very hard.
She said that while infrastructure has been destroyed along the coasts, roads and hospitals more than 5-6km inland are functioning.
Mental health will be a major issue, she continued, in the months and years ahead - bereavement, trauma and "massive psychological issues" would be a concern for the WHO.
"The other concern is to ensure that the massive amounts of money being pledged to these countries is spent wisely and builds on existing health infrastructures, to support these countries in the longer term."
Having worked in the Maldives in September has heightened her sense of shock.
"It has all felt very, very real and I have been like a cat on a griddle wanting to get back there to help. But we have teams out there, and I'll be more useful in the next few weeks."
