An aggressive strain of a common virus that has killed three NSW children aged under two since December may be responsible for a fourth death.

The NSW Coroner is investigating the death to see if it was caused by EV71, an enterovirus associated with hand, foot and mouth disease. A NSW Health spokeswoman said the department did not have specific details including the gender, age or suburbs of the children who died because it was not a notifiable disease.

Dr Bruce Thorley, of the Victorian Infectious Diseases Reference Laboratory, said a strain known as C4a that had killed hundreds of children in Asia had made its way to Australia. It could, in rare cases, cause severe neurological complications such as brain inflammation and paralysis, he said.

Dr Thorley said strains of EV71 were often circulating among the population and most infections were not cause for alarm, with mild symptoms or unnoticeable.

“But now, to have such a number of positive detections including paralysis, I would regard it as an outbreak,” he said.

In March, NSW Health saw a spike in the number of children younger than five with severe neurological complications caused by enterovirus infections, with northern and south-eastern regions of Sydney most affected. Of 120 enterovirus related admissions to children’s hospitals between January to the start of June, 18 cases were confirmed as EV71.

NSW Health has increased their surveillance of the infections and issued information to general practitioners.

An infectious diseases physician and microbiologist with the Australian National University, Peter Collignon, said good hygiene, such as hand washing and using tissues, helped prevent transmission of the disease which is spread through faeces, coughing and sneezing.

Children diagnosed with hand, foot and mouth disease should be pulled out of childcare until symptoms cleared, including blisters on the hands, feet and mouth, he said.

“Like any infection, it can make a small percentage of people very sick,” Professor Collignon said.

“If parents notice the symptoms in their child are getting worse or feel they are particularly sick they should seek medical advice immediately.”

While the impact of the disease had been devastating in parts of Asia, Professor Collignon said parents should not fear the same in Australia, where hygiene and living standards are high. A vaccine is not available though trials are taking place in China.

The original release of this article first appeared on the website of Hangzhou Night Net.