Thai health officials say water-borne diseases could be on the rise in Bangkok amid warning from Pichai Naripthaphan, the energy minister, that the country's flood crisis could last for another month.
The statements came late on Monday, as authorities issued an evacuation advisory for another neighbourhood in the Thai capital and floodwaters neared the city's center.
However, Pichai said that floods across the country may finally begin to subside in the capital by mid-November.
Klong Sam Wa is the city's 12th district that received an evacuation order during the country's worst flooding in half a century. The floods have killed more than 500 people since late July.
Yingluck Shinawatra, Thailand's prime minister, announced on Tuesday that she would not be attending the APEC summit this coming weekend in the US due to the floods.
"Now it's time for all Thai people to help each other, so I've informed [the host] that I would not go," she said.]
High-level officials and experts have given varying estimates of how long the flood threat would loom over Bangkok, but the threat has only intensified, as more neighbourhoods are inundated each day.
The floodwaters have overwhelmed canals, seeped up through drains and poured down highways.
The water has now begun surrounding the city's northernmost subway stops, threatening to shut them down.
Most victims have drowned, while a few died from flood-related electrocutions. No deaths have been reported in Bangkok.
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Renate Vuuren of World Vision, the humanitarian organisation, told Al Jazeera on Monday that people in Bangkok were tense.
"It is difficult to bring aid because of transport and access problems," she said.
"In the larger part of the country, at least a third of the country has been inundated, and in Bangkok it is almost oozing into the city."
Health is a "very big concern" for everyone, as a result of the carcasses and the accumulation of garbage, she said.
The nearby province of Ayutthaya, which has been submerged for more than one month, has the highest toll with 90 reported dead.
Floodwaters have begun receding in some provinces north of the capital, and a major clean-up is planned in Ayutthaya this week.
But the run-off has massed around Bangkok and completely submerged some of the city's outer neighbourhoods.
In the last few days, floods have also begun moving southward in adjacent Lad Phrao, a district full of office towers, condominiums and a popular shopping mall.
On Friday, workers completed a 6km flood wall made from massive, hastily assembled sandbags to divert some of the water flowing towards central Bangkok.
But large amounts of water are already beyond that wall, and officials say that besides a network of canals and underground drainage tunnels, there are no more barriers preventing water from pushing south into the city's centre.