Cases of hand, foot and mouth disease have increased more than 90 per cent in southern Vietnam, killing at least 20 children and infecting nearly 4,000, since the start of 2011, health officials said on Thursday.

There are no national statistics, but Pham Viet Thanh, director of Ho Chi Minh City’s Department of Health, said the disease had killed 13 children in the city and infected more than 3,000 this year.

He said the number of patients in May increased fourfold, compared with the same period last year. On average, 100 to 120 patients were hospitalized each day, many of them breathing with the help of oxygen.

Health officials in Dong Nai province, close to Ho Chi Minh City, have also reported seven fatalities and more than 700 infected children since January.

The disease is highly contagious among children, and 70 per cent of patients are under 3, said Truong Huu Khanh from Ho Chi Minh City’s Paediatrics Hospital. The fatality rate among those infected is below 1 per cent.

Symptoms include the appearance of small red blisters on the palms, feet and mouth as well as fever, nausea and loss of appetite.

“There is no vaccine against this virus, and the best way to prevent the disease is to ensure hygienic food and drinks and avoid contact with infected people,” Khanh said.

The virus is transmitted through saliva, blister fluid and faeces, but it is rare among adults, whose immune systems are generally strong enough to fight it off. The disease is life-threatening in a small number of cases, owing to complications such as lung haemorrhages and meningitis.

The Ministry of Health has asked local authorities to tackle the high death toll, but health staff said government officials had not provided adequate information to help parents recognize symptoms of the disease.

More In: Medicine | Health | Sci-Tech