A teacher checks a child for sores or blisters as part of stepped-up efforts to prevent the spread of hand, foot and mouth disease in Singapore in 2008. A teacher checks a child for sores or blisters as part of stepped-up efforts to prevent the spread of hand, foot and mouth disease in Singapore in 2008. (Wong Maye-E/Associated Press)

A virus closely related to polio is causing major outbreaks of hand, foot and mouth disease across the Asia-Pacific region, say researchers from the Australia, Asia and the U.K.

In some cases there are severe neurological complications, say the researchers writing this month in Lancet Neurology and Lancet Infectious Diseases. There are also fears that Australia is unprepared for an outbreak.

Enterovirus 71 was first identified in the 1960s in California, where it caused small outbreaks of hand, foot and mouth and neurological disease.

The virus has been an increasing concern since the late 1990s, when regular epidemics occurred across the Asia-Pacific region, including one in Taiwan in 1998, according to researchers. The Taiwan outbreak is thought to have involved millions of people, and 500,000 cases were reported in an outbreak in mainland China.

Hand, foot and mouth disease

Hand, foot and mouth disease (HFMD) is a common childhood ailment that typically causes little more than a fever and rash.

The highly contagious virus is normally transmitted orally or through contact with fecal matter. It typically affects children 10 years old or younger, and is prevalent worldwide.

The most common virus to blame for HFMD is coxsackievirus A16. However, sometimes the disease is caused by enterovirus 71, which can cause a severe form.

HMFD is contagious and is spread from person to person by contact with nose and throat discharges, saliva, fluid from blisters or the stool of an infected person.

There is no treatment but symptoms like aches, pain or fever can be treated with over-the-counter medications.

There is no effective anti-viral treatment or vaccine.

During an outbreak of the virus, which mostly affects children, the majority of those affected will have a mild, self-limiting illness, or one that gets better on its own, researchers say.

But a small proportion of those affected will rapidly develop severe and sometimes fatal neurological and systemic complications over days or even hours. These include aseptic meningitis, poliomyelitis-like acute flaccid paralysis and brainstem encephalitis.

Prof. Peter McMinn, a clinical microbiologist from the University of Sydney and a co-author of one of the recent papers, says it is likely the virus underwent a crucial genetic change at some point in the mid-1990s, which improved the way it was transmitted through communities and allowed it to create the larger outbreaks.

Australia has already seen outbreaks of enterovirus 71, including one in Perth in 1999 and another in Sydney in 2004.

Australia ill prepared

The continent may have been somewhat protected because of the relatively high living standards of most of the community and a geographically disparate population, says McMinn, warning there is no room for complacency.

Australia doesn't have a nationally co-ordinated or funded system to monitor the disease.

"My concern is that it could cause a large epidemic and we won't be prepared," he says.

"I think that Australians, particularly parents, should be aware of this disease. It's a disease of great concern to parents in Asia because of the devastating effects it can have on children."

With no effective treatment available for enterovirus 71, the best hope of preventing the disease lies with teams of researchers in the region who are developing a vaccine, he says.