The annual battle between residents and invading termites is worse than ever this year because of the recent warm and humid weather.
Termites have arrived earlier than last year and in larger numbers. Pest exterminators said this was because the temperatures were higher than normal in winter and spring.
Shanghai Xufang Greenery Co in Xuhui District, which specializes in termite prevention, said it had received about 100 orders in two days last week, more than the total order number for the whole of March.
"The number of calls for help to kill termites soared significantly after the Qingming Festival on April 4," said Zhang Shengqi, an exterminator.
"The higher temperature in winter and spring provided a perfect catalyst for the living and proliferation of the pests, and the recent frequent rain after Qingming was extremely suitable for their growth."
Zhang added more than 30 orders a day from the Xujiahui area were received on two peak days earlier this month.
Most of those seeking help were living in old wooden houses or on the first floor where water pooling and humidity attracted large numbers of termites. Between noon and 3pm was the most active time for termites because that was when it was hottest, Zhang said.
Yongjia Road, Jianguo Road and Huaihai Rd M., home to large numbers of old wooden structures, were some of the worst-hit areas, exterminators said.
Nanfang Greenery and Termite Control Service Center in Huangpu District said it had witnessed a 20 percent increase of orders on Monday compared with orders made during the weekend.
An exterminator surnamed Qian said thousands of termites were seen at a household on Zhongshan Rd S., scaring residents on Monday afternoon.
"April is the peak movement time of termites, and their invasion will gradually abate in May," he said.
Pesticides were not the solution because termites then flew around everywhere and found new nests, exterminators said.
Cracks by doors and walls should be covered, and wooden boxes should be checked closely.