Viral campaign

When summer in Beijing comes, it comes fast. Before you know it, Beijingers are out celebrating the hot season. It is not merriment for all though. For parents the warmer months of the year also bring them bad news: hand, foot and mouth disease, a highly infectious and potentially fatal disease, is kicking back in. And it is apparently more intense this year, health experts have warned. News of a breakthrough in the battle against hand, foot and mouth disease have just been announced, but will this bring respite to anxious parents?

Classified class C

Hand, foot and mouth is a viral disease that affects children, mostly under the age of three, and can result in paralysis or even death. Touch and contact with the fluids or feces of the infected is usually enough to contract the disease.

In the spring to summer of 2008, an outbreak of hand, foot and mouth disease hit Fuyang, Anhui Province. Chinese authorities reported 3,736 cases, with 22 deaths, between January and May. The epidemic jolted China into designating the disease, up until then not officially monitored, as a class C notifiable disease, meaning reporting is obligatory by law.

Children younger than five years of age accounted for 92 percent of the 61,459 reported cases across China that year, according to a report by the World Health Organization (WHO).

Nationwide case reporting and the death toll rose rapidly in the following years and the same pattern has been observed locally in Beijing as well, official statistics show. 2011 was relatively better, with about nine percent fewer cases reported and fatalities dropped by nearly 44 percent compared to the year before.

But things have started getting worse again. Take the first week of April for example. The Beijing Municipal Bureau of Health registered 306 cases between April 2 and 8, more than double the number of the same week last year.

Lying just north of Beijing's Ditan Park, Dongcheng district, immunology professor Wu Jiang's disease surveillance office, under the Beijing Municipal Center for Disease Prevention and Control (CDC), is working daily monitoring the spread of hand, foot and mouth disease across the city. More cases have been reported to the CDC in the first quarter of the year than the same period last year. "The disease appears to be on the rise," Wu told the Global Times. "I don't want you to panic if you see the figures because, 14 weeks in, we are still just looking at a small segment of the curve," Wu said. May to August is always the worst season, he told the Global Times.

An atomic breakthrough

A group of scientists at the Institute of Biophysics (IBP) in Beijing have announced they obtained a high-resolution image of a virus known to be responsible for the disease. New findings about the structure of the virus, known as enterovirus 71, or EV71, point to new opportunities for antiviral therapy, they claimed in an article published on March 4 in the journal Nature Structural & Molecular Biology.

While other agents are also known to cause hand, foot and mouth disease, EV71 has historically been the worst. In the 2008 outbreak in China, 54.5 percent of the cases reported were confirmed to be EV71 infections. In 2009, EV71 was responsible for 81 percent of the most severe cases and 93 percent of the deaths, according to WHO data.

Taming EV71 has since become the holy grail of global virologists and health professionals.

In their article, coauthored with scientists from Oxford University, the IBP researchers detailed how they produced an atomic model of the structure of EV71. In other words, they can now see every atom of it.

More promisingly, their study revealed an intermediate stage of this virus, previously unknown to scientists, which they believe sheds light on how it infests host cells. "After EV71 binds to a human cell, it releases its genetic material (RNA) into the cell. The way to fight infection, therefore, is to stop the releasing," said biophysicist Peng Wei, 28, one of the coauthors of the article and lead member of the IBP research team.

Using a cutting-edge instrument called a synchrontron, Peng and his colleagues discovered holes in the shell of EV71. These holes may be how the virus lets out its RNA, they believe.

"No one has ever seen a mature EV71 particle with holes in its shell, but it has been our hypothesis that there must be holes when it releases its RNA. We just have never been able to observe the process, which is called uncoating," Peng said. Uncoating is when a virus sheds its shell to let its RNA out.

The virus they observed is not one ready to attack human cells. Rather, it is in the virus' immature state, empty of its RNA. The researchers proposed in their article that this empty state is markedly similar to the mature state, when a virus is ready to attack. "We know that something about its protein composition happens to a virus during uncoating," said Peng. The implication: if they can tailor-make a small molecule inhibitor that hinders the uncoating, there is potential for future antiviral drugs.

Race against time

China has been racing to develop vaccines for hand, foot and mouth disease. In December 2010, the State Food and Drug Administration (SFDA) granted approval to clinical trials of the vaccine against EV71. Since then, the first two phases have been completed in less than 11 months. IBP has shared its study with three pharmaceutical companies undertaking such trials, Peng said.

At a national vaccine development center in Beijing, where China put in 210 million yuan ($33,397,404) in initial investment in 2010, the clinical trial is in its third, or final, phase, before permission for commercial production from the SFDA can be expected.

In Beijing, CDC is strengthening its work on hand, foot and mouth disease prevention to accommodate the seasonal flux. Collecting and analyzing data is labor-intensive and keeps half of Wu's staff busy.

CDC is also enhancing health education on personal hygiene and sterilization in schools, especially in schools for children from underprivileged families, such as migrant workers. The latest IBP study will help drug development, Wu said, but until a vaccine or antiviral drug is available, prevention is the key. "The best vaccine," said Wu, "is good hygiene."