Syphilis in China

Introduction

Syphilis was first documented in China in 1505. By the 1940’s, Syphilis had become a major epidemic within China. As the communist party took over China in 1949, the political party made the disease a priority and launched a campaign in 1952 to abolish the disease [1]. Before the party launched its campaign, it was estimated that 5% of the population in large cities carried the disease. The campaign consisted of wide screening, free treatment, and a crack down on prostitution – a major factor for the spread of the disease [2]. By 1964, Syphilis had become a rarity and infection nearly eliminated, until its international borders were opened in the 1980’s [1].

A natural development of immunity towards Syphilis is possible. However, due to the fact that China had been “cleaned” of Syphilis for about 20 years after the campaign, the young sexually active generation lacked the natural immunity. This resulted in detrimental effects to China when unprotected sexual contact was made with foreigners that had the disease [1]. The disease spread over time, as sex education was practically nonexistent and public awareness of the disease dwindled. The result was a heavy resurgence of Syphilis in the late 1990’s and early 2000’s. Recent data has shown that the rate of syphilis has jumped from 0.2 cases per 100,000 people in 1993 to 5.7 per 100,000 in 2005. In even larger cities, such as Shanghai, the rate is estimated to be as high as 55 cases per 100,000 people [2]. Congenital syphilis cases, in which the disease is passed on through the mother to a newborn, are estimated to be about 3,400 a year [2].

Description of Syphilis

Syphilis is a spirochetal bacterium known as Treponema Pallidum. “The spiral-shaped body of T. pallidum is surrounded by a cytoplasmic membrane, which is enclosed by a loosely associated outer membrane. A thin layer of peptidoglycan between the membranes provides structural stability.” T. Pallidum contains spirochetes that have an endoflagella which allows the bacteria to move in a corkscrew formation through the viscous fluid of the periplamic space; thus T. Pallidum is a Gram Negative Bacterium.

What is interesting to note is that T. Pallidum cannot live independently. It can only survive inside host cells of mammals, thus T. Pallidum is an endosymbiont. Once it penetrates into the host cell, “T. pallidum derives most essential macromolecules from the host, using interconversion pathways to generate others.”

T. Pallidum has a slow growing rate relative to other bacteria. One reason is due to the fact that T. Pallidum does not contain a tricarboxylic acid cycle and an electron transport chain. So it depends only on glycolysis, which makes 2 ATP molecules per glucose. Therefore the low energy source slows the growth rate significantly. Moreover, “because of a lack of enzymes such as catalase and oxidase that detoxify reactive oxygen species, the in vitro survival of T. pallidum is prolonged by low oxygen concentration.”

Another interesting fact is that T. Pallidum lacks lipopolysaccarides (LPS) in their outer membrane. Most Gram Negative Bacteria contain LPS, which is an endotoxin; but T. Pallidum does not such that it prevents the cause of fever or inflammation in the body.

Finally, motility of the T. Pallidum depends upon adhesions and the process of chemotaxis. The bacteria use its pili as an adhesion to attach to host cells, and they use treponems in the adhesion process. Moreover, T. Pallidum uses methyl accepting chemotaxis transmembrane proteins (MCPs) that “sense attractants and repellents in the environment; glucose and histidine are molecules that may have affinity for T. pallidum MCPs. Pathogenic processes such as crossing the endothelial barrier to reach the bloodstream are likely to depend upon mechanisms that allow T. pallidum to sense and respond to nutrient gradients.”

Syphilis’s microbe, Treponema Pallidum, has very strong motility to swim through gel-like fluids; but it is a sensitive bacterium that is very dependent on its host cell to survive. If this Gram Negative Bacterium is removed from the mammalian cell it will die within hours because of the lack of nutrients that the host cell can provide.

Transmission of disease

How is it transmitted? Is there a vector (animal/insect)?

Why is this disease a problem in China

The rising rates of syphilis in China is largely attributed to factors regarding socioeconomic, educational and lifestyle issues (?). The current clinical guidelines for syphilis detection are based on symptomatic criteria, overlooking opportunities to assess risk factors to further improve disease control. This method does not include blood tests, such as the toluidine red unheated serum test (TRUST) and Treponema pallidum particle agglutination test (TPPA), which can detect syphilis even if an individual does not show any hallmark symptoms of the disease. In a study investigating the effectiveness of a potential screening tool, 40.9% of patients that tested seropositive did not show the hallmark signs of syphilis.

Large number of migrant workers in China Increasing prostitution More extramarital sex Low condom use Lack of health care avaiability for everyone Deter people from getting tests done early and having subsequent treatment Chinese society conservative Little open discussion about sex at any level Inhibits exchange of information at all levels Within families Sexual relationships Campaigns in schools & universities Media Chinese adults had no exposure to syphilis for decades Left population with low immunity

Source: http://news.bbc.co.uk/2/hi/asia-pacific/6253807.stm

Overall: The symptons of syphilis can be wide ranging, often bieing confused with other conditions, and may also be asymptomatic, making diagnosis a particular challenge (Hesketh).

Do lifestyle/environment/economics/political issues play a role?

What is being done to address this problem

Dr. Mryon S. Cohen, who has worked in China since 1979, worked in collaboration with Dr. Xiang-Sheng Chen from the National Center for STD Control in Nanjing to compile a report on the Syphilis resurgence. The complied report provides data to let the government know where to allocate their resources. As a result, a “China Syphilis Working Group” has formed, working with the UNC, China's National Center for STD Control, the World Health Organization, the United Nations Center for Disease Control and the London School of Hygiene [1].

What else could be done to address this problem

In 1949, China experienced one of the worst syphilis epidemics, estimating that 5% of the population is large cities carried the disease. As the Communist party took power, free treatment and screening was offered for the disease. The Communist party cracked down on prostitution as well, which results in a near elimination of syphilis [2]. Ironically, due to the near elimination of Syphilis by the Communist party in the 1960’s, the unexposed Chinese population lacks this natural immunity, making them more susceptible to the disease [2] as their borders were opened internationally in the 1980's.

One important factor that contributes to recent outbreaks is the fact that more people are more people are moving to larger cities for work, resulting in an increase in demand for prostitutes with low use of protection [2]. Another is the lack of use of protection among homosexual males [3]. Premarital sex has become more acceptable within Chinese culture, resulting in larger outbreaks. There are also less adult screening programs for syphilis [2].

Treating the disease in China is not a scientific problem, but a socio-political problem. China remains one of the most conservative countries in the world. As a result, topics of sexual intercourse are generally taboo, as well as sexually transmitted diseases [3]. To combat the vast increase within the past decade, China should reform it's educational system to include sex education. They should also publicly promote the use of protection. An entire reform from it's conservative culture is essentially required to best to address the problem. In addition, new adult screening programs should be established and antibiotics should be made easily available by the government to deal with the current syphilis outbreaks [2], as it did in 1949.

References

[1]. University of North Carolina School of Medicine. "Resurgence And Spread Of Syphilis In China Is A Rapidly Increasing Epidemic." ScienceDaily. 12 January 2007. 25 August 2009 <http://www.sciencedaily.com/releases/2007/01/070112104258.htm>.

[2]. Roxanne Khamsi. “Syphilis rates skyrocket in China.” New Scientist. 12 January 2007. 25 August 2009 <http://www.newscientist.com/article/dn10940>.

[3]. Iamseven. “Syphillis on the rise in China.” Digital Journal. Jan 11, 2007. 25 August 2009 <http://www.digitaljournal.com/article/90014>

Edited by [insert your names here!], students of Rachel Larsen