An uncommon virus has caused a 74 percent increase in hand, foot and mouth disease cases in the past three months, city health officials said yesterday.
The main cause of this year's HFMD cases has been the Coxsackievirus A6 virus, which is different from the usual Coxsackievirus A16 and Enterovirus 71 strains, according to the Shanghai Center for Disease Control and Prevention.
"The outbreak of new viruses usually leads to an increased number of victims," said Pan Hao, director of the SCDC's communicable disease control and prevention institute.
"Communicable diseases often see a spike every few years. After a record low for 2015, 2016 has reported a peak, especially in June, July and early November."
Shanghai reported a total of 21,782 HFMD cases in June and July this year, a 67.8 increase from last year. The number for November has not been released, but the SCDC estimates it could be double that of November last year.
The number of HFMD cases reported from August 28 to November 19 saw a 74 percent increase compared to the same period last year, the SCDC said.
HFMD usually occurs in spring, summer and autumn, and the viruses generally disappear with a drop in temperature.
"What is unusual about this year is that the number of HFMD cases did not drop, as it usually does, in October, and the situation has lasted until November," Pan told Shanghai Daily.
Shanghai entered autumn comparatively late this year. Pan said there is no scientific proof that the "long life" of HFMD viruses this year was caused by the weather, but added rainy conditions might have contributed.
HFMD usually occurs in children under five. The infection typically begins with a fever, which is followed by flat discolored spots or bumps and blistering on hands, feet, the mouth and sometimes the buttocks and groin.
The rash generally goes away on its own in one or two weeks. The viruses causing HFMD can be spread through direct contact with fluid from a patient's blisters, or droplets from the nose and throat, as well as the feces of a patient.
The SCDC says those infected should not go to school or work. Their clothes, tableware and towels should be disinfected regularly.
Shanghai has three hospitals that specialize in HFMD — the Children's Hospital of Shanghai, the Children's Hospital of Fudan University and the Xinhua Hospital.
Children's Hospital of Fudan University reported 13,645 HFMD cases by November 27 this year — 43 percent more than last year. Over 50 percent more patients had been received during the peak from May to August.
"The disease had been detected among more young patients since September compared to last year," Zeng Mei, director of the hospital's communicable diseases department told Shanghai Daily. "But not many serious cases had been reported in the past two months, so parents don't have to worry too much."
Zeng said HFMD saw another peak after October mainly because it had been spread among children in kindergartens after a new semester started.
Neighborhood health centers began administering vaccines last month.
The Chinese-developed shots target the Enterovirus 71, which causes about 40 percent of HFMD cases and is the cause of most serious cases and deaths. Shots cost 200 yuan ().