MEDICAL experts are warning of an outbreak of disease in Bangkok as the floods look set to recede and the government says the cost to the Thai economy may exceed $A30 billion.
The Australian embassy in Bangkok is urging travellers to reconsider their travel plans and to exercise caution.
Thai officials from the Irrigation Department today said half of the millions of cubic metres of floodwaters had flowed into the sea but another 11 days were still required before Bangkok was completely drained.
Several areas of Bangkok and neighbouring regions are inundated as waters from the north edge their way through the capital to the Gulf of Thailand. Bangkok governor Sukhumbhand Paribatra said the city was facing a net inflow of 100 million cubic metres of water a day.
The floods, the most severe in 50 years, have claimed 529 lives and still affect 24 provinces, the Disaster Prevention and Mitigation Department reported.
The University of the Thai Chamber of Commerce says damage to property and assets could be as high as $33 billion, with up to one million left unemployed.
The floods hit seven industrial estates in Ayutthaya and Pathum Thai provinces north of Bangkok, causing massive disruption to supply chains for the car, electronics, hard disk drive and other key industries.
Today, workers at industrial estates near Bangkok were hoping to hold at bay floodwaters still making their way through the capital, raising fears factories due west from the capital, largely focused on food processing, would be hit.
Thai Prime Minister Yingluck Shinawatra has earmarked $4 billion from its latest fiscal budget for 2012, announced this week, to compensate flood victims and for post-flood rehabilitation.
Tourism officials are also counting the cost. Tourism Authority of Thailand (TAT) Governor Suraphon Svetasreni told reporters tourist arrivals had fallen by 25 per cent in recent weeks.
Suraphon said if floods continued until the end of December total revenue losses could reach $A825 million, of which $A387 million would be losses from international tourism.
He said the situation remained uncertain.
"If you say it's not safe there's evidence to say it's not safe. At the same time you say it's safe, you still have some upcoming, unknown factors. So I still cannot say it's safe or I cannot say it's not safe," he said.
Suraphon said tourists should focus on other destinations within Thailand such as Phuket Island ahead of the peak holiday Christmas season.
Visitor arrivals for 2011 are expected to come in at 19.1 million, down from 19.5 million initially forecast.
Thailand's international airport of Suhvanabhumi remains open, with the airport perimeter sandbagged to a height of 3.5m. But the domestic airport of Don Muang has been shut due to flooding since late October.
The Australian embassy is recommending to visitors to "reconsider your need to travel", except for Suhvanabhumi International Airport, due to the transport disruptions "and reduced access to essential services caused by severe flooding".
Australian officials said the outlook "was hard to predict", with fears the central parts of Bangkok, still dry, could still be inundated if dykes collapsed from carrying weeks of pressure from the rising waters.
But health officials warn against a spread of disease, even as the waters recede.
Rekha Hanvesakul, a doctor at BNH Hospital in Bangkok, says Thailand's health system is facing a major test to cope with the floods' aftermath.
"It's definitely a big challenge because of the quantity or mass of water that's coming through. I don't think we've ever had to deal with such large amounts of water," Dr Rekha told AAP.
"If it's one or two days people can manage to deal with this. (But) because the quantity of or mass of water is so huge and a lot of people are living under these conditions for a long periods of time disease becomes a real issue," she said.
Doctors are already warning people, especially women, of the dangers of infection from water contaminated by animal urine that can lead to leptospirosis, with symptoms of fever, headache, nausea and vomiting.
Other causes of concern include cholera and gastrointestinal diseases, such as typhoid. BNH also warns of poisonous snakes, scorpions and centipedes in the water.
"Of course things like typhoid, which again comes from salmonella bacteria, unclean food, water, unhygienic methods, not washing your hands after going to the bathroom or defecating in flood waters just because there are no toilets," she said.
Dr Rekha said visitors to Bangkok should have second thoughts before travelling. "I think this is not a good time to tour Bangkok for sightseeing for any purpose," she said.
"But if they do come for business issues or other issues they need to be informed of the flooding situation - where they can live, where there will be no floods, and they really need to be updated on this.
"There are places at the moment that are not flooded. (But) we're not sure what will happen in the next week or two," she said.
AAP
Das Bild zeigt einen Helicopter der US Navy über den überschwemmten Gebieten im Großraum Bangkok 
 Das Rekordhochwasser, das seit mehreren Monaten in Thailand herrscht und in den beiden letzten Wochen Teile der Hauptstadt Bangkok überschwemmt hatte, weicht langsam zurück. Es soll noch mindestens zehn Tage dauern, bis der Großteil des Wassers abgelaufen ist. Gleichzeitig steigt die Gefahr, dass in den Hochwassergebieten Seuchen ausbrechen können. Einige Staaten, darunter Australien, haben Reisewarnungen herausgegeben. Mindestens 529 Menschen sind in den Fluten ertrunken, die Ende Juli begonnen hatten, als die Ausläufer eines tropischen Sturmes im Norden und Nordosten Thailands zu erheblichen Starkregenfällen führten.

Bang Phlat, einem Stadtbezirk auf dem westlichen Ufer des Chao Phraya (Aufnahme vom 31. Oktober) 
Bei dem Hochwasser handelt es sich um das schwerwiegendste in Thailand seit fünf Jahrzehnten, und noch immer sind 24 Provinzen des Landes betroffen. Nach Angaben der Universität der Thailändischen Handelskammer kann der Sachschaden 33 Milliarden australische Dollar erreichen. Durch die Auswirkungen hätten etwa eine Million Thailänder ihren Job verloren.

Der internationale Flughafen der Stadt, Bangkok-Suhvanabhumi, wird von einer dreieinhalb Meter hohen Mauer aus Sandsäcken geschützt, doch der für den innerstaatlichen Flugverkehr genutzte Flughafen Don Muang ist seit Ende Oktober überflutet.

Die Bevölkerung mit Nahrungsmitteln und Wasser zu versorgen, wird immer schwieriger. Mineralwasser ist in den Läden seit Wochen häufig ausverkauft. Durch Überschwemmungen der Straßen reißen die Lieferketten ab. Betroffen ist seit kurzem auch eine Autobahn nach Bangkok, die aus dem Süden kommt.

Durch den Produktionsausfall bei Festplatten sind weltweit die Preise angestiegen. Preissteigerungen von 80 bis 100 Prozent waren zu verzeichnen.