A few weeks ago, at Shanghai's new infectious disease hospital, one of the city's leading AIDS specialists had to tell a new mother her son was probably infected with HIV.

"She found out after she gave birth that she was HIV positive. I think the baby was infected because he has had a recurrent fever," said Lu Hongzhou, vice-director of the department of infectious diseases at the Shanghai Public Health Centre - one of China's most modern infectious disease centres built after the SARS (severe acute respiratory syndrome) outbreak in 2003.

The woman was from a rural area, Lu said, where testing is minimal if it is done at all. Her case underscored one of the biggest challenges facing doctors, officials and activists: "We cannot find all the HIV carriers."

Tracking down infected children is particularly difficult. Government estimates put the number of children infected in China at between 1,500 and 2,000. But to date health workers and authorities say they have managed to reach only one-10th of them.

The problem is a lack of basic information and social stigma attached to the disease.

Families hide children once they learn they are infected; they take them out of school, move them out of the reach of doctors and keep the knowledge buried.

This stigma is coupled with widespread fear of the often-vicious side effects of anti-retroviral drugs - side effects that can be particularly serious when children use drugs meant for adults.

In May, the United States-based Clinton Foundation launched a programme to provide free paediatric drugs in half a dozen countries around the world. China was the first. The foundation budgeted doses covering 2,000 children for a year. To date only about 200 cases have been identified, according to the foundation's Christina Ho.

Shanghai is an example of the hurdles faced in treating infected children.

"In Shanghai there are only a few cases, but we never found the children, so they never got the treatment," said Pan Xiaozhang, an AIDS specialist at Shanghai's Huashan Hospital. "I think the children problem is very serious."

This deadly game of hide-and-seek only exacerbates the difficulties of treating children living with HIV/AIDS.

Anti-retroviral drug cocktails, widely available to adults, are much more difficult to administer to children. Children need different and milder formulations. Dosages change depending on their age and size.

Just diagnosing them can pose complications. In recent studies, the non-governmental international health organization Medicins Sans Frontieres (MSF, also known as Doctors Without Borders) does not include children younger than 18 months.

Costly treatment

Price is another barrier. Drug cocktails available for children can be four times as expensive as those for adults.

Low prices for locally produced first-line adult drug cocktails - the first treatment an infected person can take before developing a resistance and having to switch to second generation treatments - have allowed the government to publicly offer free drugs to all adult patients as part of its "Four Frees and One Care" programme.

But virulent side effects and a lack of variety often keep patients away. The most common treatments produced in China do not work well with a common strain of the virus that goes hand in hand with hepatitis. In fact, one of the treatments' components exacerbates hepatitis.

On the other hand, the fact that affordable drugs are available at all is an improvement. For years, drug prices in China - and around the world - were just too high.

Since the turn of the millennium prices have dropped from thousands of US dollars per year to less than a couple of hundred in some cases because of mass production and distribution, particularly in India.

"It was generic production that brought down the prices of AIDS drugs from over US$10,000 to as little as US$150 per patient per year," Ellen Hoen, director of policy advocacy for MSF, said in a report for a world conference on HIV/AIDS in Brazil in July.

Still, second-line treatments and drug combinations with milder side effects are still very expensive. Children's formulations are similarly expensive and can cost thousands of US dollars per year.

A number of factors have combined to keep drug companies from producing generic children's drugs. The low number of child patients means the market is small.

It is also much more difficult to ship and store children's treatments which are often in syrup form and must be refrigerated. Others are powders that require clean drinking water, while liquid formulations can be difficult to measure.

The result is that infected children are given adult medicines ground up to adjust the dosages.

Before the Clinton Foundation got involved, children's anti-retroviral treatments were basically not available to the Chinese population at large.

Inadequate attention

At the same time, attention was seldom paid to the statistically tiny number of children living with HIV/AIDS. Government programmes tend to target the much larger groups of sex workers, intravenous drug users, blood donors and migrant workers.

"No expert now thinks children are a bridge population," said Xu Wenqing at UNICEF, the United Nations programme that focuses on children.

Still, while other groups are more likely to spread the virus into the general population, doctors and activists believe more attention should be paid to children.

"Children and adults alike who are HIV positive should be treated," Ho said.

Now the drugs are available, the problem may not be availability but willingness to come forward.

"Most children with HIV are not hospitalized until the full-blown stage," said Zhu Qirong, a Shanghai-based paediatric specialist.

"In some cases the children die of organ failure, and in others the effect of treatment is not good because HIV/AIDS drugs often have big side effects on children.

"It is really a big question of how to have infected children receive treatment before it is too late."

Societal mores may be one of the tallest hurdles to eradicating or just combating the epidemic among children.

"Most HIV-infected (children), when they find they have HIV, are kicked out of school," said Bill Valentino, Bayer's manager of corporate and social responsibility, who has been in China for 16 years and is one of the leading proponents of corporate involvement.

This lack of general willingness to even diagnose the disease may be the only reason new cases even develop in children.

"It's actually very rare in the West to see paediatric cases," Ho said.

Mother-to-child transmission is the most common cause of HIV in children, but technically it is completely preventable.

The options to prevent it are not always attractive terminating the pregnancy is one of them but medicine has theoretically done away with HIV in newborn children.

Still the number of known mother-to-child transmissions has grown every year since 1995, according to a joint report by the Ministry of Health and the UN Theme Group on HIV/AIDS.

"About 60 per cent of babies of HIV/AIDS-infected mothers turn out to be positive in HIV/AIDS tests," Zhu said.

"One main challenge in dealing with HIV/AIDS cases of children is to avoid infection of pregnant women," Zhu said.

Ultimately, the only sustainable solution may be education towards getting rid of the stigma and allowing patients the freedom to be tested without facing repercussions at home, work or school.

(China Daily September 22, 2005)