China is witnessing an alarming increase in the number of babies born with syphilis, a potentially fatal disease that experts say was virtually wiped out five decades ago.
Research shows cases have risen sharply in the last 10 years - and in coastal cities, such as Shanghai, it is ranked as one of the most commonly reported sexually transmitted diseases (STDs).
The rate of increase is unprecedented since the introduction of penicillin. But it is the soaring number of newborn sufferers that has sparked the greatest concern, say analysts.
A total of 9,480 babies were born with congenital syphilis in 2008, more than one each hour, according to research published last month by the New England Journal of Medicine. A separate study in the Lancet, another well-respected journal, said the figure had risen by more than 70 percent year on year since 1991.
Catching out the 'imitator'
Syphilis is a sexually transmitted disease caused by a bacterium called treponema pallidum. The illness is often called "the great imitator" as its symptoms are indistinguishable from many other diseases.
How do people get syphilis?
Syphilis is passed through direct contact with a syphilis sore. Sores occur mainly on the external genitals or in the rectum, but can also occur on the lips and in the mouth.
What are the symptoms?
Many infected people do not have symptoms for years, yet remain at risk if they are not treated. Although transmission occurs through sores, many are unrecognizable as syphilis.
What happens during the primary stage?
This is usually marked by the appearance of a single sore (a chancre) but there may be multiple sores. The time between infection and the first symptom can range from 10 to 90 days (average 21 days). The chancre lasts three to six weeks and heals without treatment.
What happens during the secondary stage?
Skin rash and mucous membrane lesions appear on the body. The rash is usually not itchy but may appear as rough, red or reddish brown spots on the hands and feet. Sometimes rashes are so faint that they are not noticed.
What happens during the latent stage?
The latent stage can appear 10 to 20 years after infection. The disease can damage the internal organs, including the brain, nerves, eyes, heart, blood vessels, liver, bones and joints. Symptoms include difficulty coordinating muscle movements, paralysis, numbness, gradual blindness and dementia. This damage can even cause death.
Liu Gang (not his real name), a 40-year-old farmer from Shenyang in Liaoning province, learned that his new son had the disease in February a month after his wife died during delivery. "I felt like the sky had collapsed on top of me," he told China Daily.
"When I first saw the (baby's) symptoms, I was a little surprised," said Li Lingyun, deputy director of dermatology at Shenyang No 7 Hospital, where Liu's son was treated. "He had little red spots almost everywhere on his body, particularly his forehead, groin and armpits."
Blood tests showed Liu's wife was suffering syphilis during pregnancy, but the family had no idea until after her death. Depending on the length of time of the infection, the disease can cause pregnant women to go into premature labor and increase the risk of stillbirth.
Doctors say the syphilis bacterium can also easily pass from mothers to embryos in the womb through the placenta.
Without urgent treatment, child sufferers - many of whom are born without obvious symptoms - are prone to serious development problems and seizures, and have only a 50-percent chance of surviving infancy, according to research in the New England Journal of Medicine.
Although syphilis is difficult to diagnose, experts blame the staggering increase on shortcomings in the country's screening process, and have urged more couples to carry out pre-marital and pregnancy health checks to catch potential dangers early on.
"The lack of compulsory periodic screening for pregnant women, as well as people's ignorance of syphilis symptoms, is resulting in an increasing number of women giving birth to syphilis-infected children," said Wan Shaoping, a professor at the Sichuan Institute of Dermatology and STD Prevention.
Pre-marital check-ups were switched from being mandatory to voluntary in 2003, "but that does not mean they are not important", said Wan, who called on authorities to do more to raise awareness of antenatal diagnosis, genetic counseling and other preventive technical services.
A couple in their late 20s whose 1-month-old son was diagnosed with syphilis in Wuhan, capital of Hubei province, admitted they did not undergo health checks before they tied the knot or during the pregnancy.
They were only alerted to the child's condition by the fact he was unable to move his right wrist, which was red and swollen.
"From his symptoms, we suspected it might be syphilis-related bone damage," said Zhao Min, an associate chief physician at Wuhan Institute of Dermatology and STD Prevention.
Although the disease was transmitted to the boy through his mother, blood tests show his father was the first to be infected. "The couple was full of remorse," said Zhao. "If they had done checks either before marriage or during pregnancy, the virus could have been found before it was transmitted to their child."
Zhou Hongyu, director of education at Huazhong Normal University and a member of the National People's Congress, the nation's top legislative body, has proposed offering free check-ups to couples in more cities and regions.
Syphilis was almost eradicated in China in the 1960s and 1970s thanks strict nationwide efforts to control the spread of the disease.
One contributing measure unleashed in the 1950s was a tough crackdown on the commercial sex industry. Police closed hundreds of brothels, while thousands of prostitutes were treated with penicillin and offered health advice on how to prevent contracting STDs.
"Although syphilis was virtually wiped out at that time, the source of infection lingered in some regions, particularly in ethnic minority areas," said professor Wan.
By the 1980s, as the country opened up and moved increasingly towards a market-orientated economy, a threat also came from the droves of foreigners who were arriving not only with new ideas and technology, but also the syphilis virus. This fact, coupled with an increased demand for sex workers from rich business leaders and migrant workers, has helped steer a sharp upward curve in reported cases over the last two decades.
The number of infections jumped from 1,982 in 1991 to 306,381 in 2009, according to Ministry of Health statistics, putting syphilis third in the nation's list of the most dangerous infections diseases.
Research published in the Lancet indicated there are now about six cases for every 100,000 people in China.
"The bacterial infection reemerged in the 1980s as the economic boom increased migration to cities by rural workers," explained Chen Xiangsheng, deputy director of China's National Center for STD Control, in a recent World Health Organization bulletin. "Migrant workers, mainly young men who have left their wives back in their hometowns, make up much of the clientele of low-tier sex workers.
"It's difficult to promote condom use among these prostitutes because they are poorly educated and some cannot even afford a condom," added Chen, who co-authored the paper on syphilis published in the New England Journal of Medicine.
Infection rates have also soared among farmers and retired people, according to a 2006 report on syphilis and gonorrhea by the STD center of the Chinese Center for Disease Control and Prevention.
"Even if they know they have caught syphilis or another STD, these three groups are often too ashamed to see a doctor because of the stigma, and will most likely pass the virus to their spouses," said professor Gong Xiangdong at the STD center.
Chinese people are still deeply conservative when it comes to discussing sexual health, and discrimination against those diagnosed with STDs, as well as many other conditions, remains a real problem.
Because of this reason, studies that suggest more than half of China's syphilis sufferers do not seek the medical treatment they need.
Although the explosion in cases of syphilis has already drawn attention from the central government and health experts, critics argue that work to curb the epidemic are falling far short of the mark.
"China has made great progress in preventing the spread of HIV and AIDS in recent years," said Wan at the Sichuan Institute of Dermatology and STD Prevention. "But even though monitoring and controlling syphilis is not technically difficult, the government is still failing to do enough."
He has called for authorities to introduce a systematic program for syphilis testing and control for high-risk groups as soon as possible.
Free screening is already offered in major cities like Shenzhen, an industrial hub in Guangdong province, but experts say such services should be rolled out in rural areas, especially counties with large concentrations of ethnic groups.
Studies show people with syphilis have an increased risk of acquiring and transmitting the deadly HIV virus, "so why not make full use of existing facilities (to curb the spread of HIV) to publicize, test and treat syphilis at the same time?" added Wan.
According to the New England Journal of Medicine report, an ongoing project is already analyzing the impact of expanded STD care on the rate of HIV infections.
Meanwhile, government programs have laid the foundations for change by introducing syphilis testing at non-traditional sites, as well as allowing the development of advocacy organizations and support groups.
China's disease control officials are also finalizing a nationwide syphilis prevention and control plan, which will be aimed at drastically reducing the infection rate over the next five years.
"Broader recognition of STDs as a public health concern, renewed financial commitment by the government and technical support from advocacy organizations are imperative if syphilis is to be controlled once again," said Wan.
Ultimately, he said, the solution lies with individuals, who must ensure that they and their partners are healthy before they have sex.
"Being cautious about your own health is not only showing respect to yourself, but also shows respect to the people you are with," he added.
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