Syphilis in Korea: Why Testing Matters Even Without Symptoms

Syphilis in Korea is drawing renewed attention as cases continue to be reported domestically and in other countries. Increased international travel and cross-border movement have also raised concerns about imported sexually transmitted infections.

According to Seoul city data cited in the original Korean report, syphilis accounted for the largest share of imported infectious disease cases identified in Seoul so far this year. Korea Disease Control and Prevention Agency data also show that syphilis continues to be reported domestically, while increases have also been observed in Japan, the United States, and parts of Europe.

What causes syphilis?

Syphilis is caused by the bacterium Treponema pallidum.

It is mainly transmitted through sexual contact with an infectious lesion on the skin or mucous membranes. Transmission can occur through lesions around the genitals or anus, as well as through affected areas of the lips or mouth.

Syphilis can also be transmitted from a pregnant woman to the fetus through the placenta, which can result in congenital syphilis.

Syphilis may cause few or no obvious symptoms

One of the reasons syphilis can go undetected is that early symptoms may be mild, painless, or disappear without treatment.

In primary syphilis, a small ulcer may develop at the site where the bacterium entered the body after an incubation period of about 10 to 90 days. The lesion is often firm, round, and painless.

Because the ulcer may disappear within several weeks even without treatment, some people may assume the infection has resolved. However, the disappearance of the lesion does not mean the bacterium has been eliminated from the body.

What happens if syphilis is not treated?

Untreated syphilis may progress to the secondary stage.

At this stage, the infection can spread through the bloodstream and cause a rash on the trunk, arms, legs, palms, or soles of the feet.

Other symptoms may include:

• Fever
• Sore throat
• Muscle aches
• Swollen lymph nodes
• Lesions in or around the mouth or genital area
• Wart-like lesions around the genitals or anus

However, secondary syphilis can also cause only mild or nonspecific symptoms. Skin rashes may be mistaken for allergies or other skin conditions, while fever or muscle pain may be interpreted as a common viral illness.

Can syphilis remain hidden for years?

After the secondary stage, syphilis may enter a latent phase in which there are no visible symptoms.

In some untreated patients, the infection may eventually progress over a long period and affect the nervous system, cardiovascular system, or other organs.

For this reason, the absence or disappearance of symptoms should not be used to assume that the infection has cleared.

Why testing matters even when you feel well

Because syphilis may be asymptomatic or cause temporary symptoms, testing can be important after a possible exposure even when a person feels healthy.

Early detection allows appropriate antibiotic treatment to begin before the infection progresses or is unknowingly transmitted to others.

Dr. Min-Jong Lee of Goldman Urology Clinic Gangnam emphasized that syphilis can be treated appropriately when detected early, but delaying diagnosis because symptoms appear mild may allow the infection to persist and increase the risk of transmission.

He also noted that after a suspected exposure, appropriate testing and treatment are more practical than avoiding care because of embarrassment or anxiety.

Can condoms completely prevent syphilis?

Correct condom use can reduce the risk of sexually transmitted infections.

However, syphilis lesions may be present on skin or mucous membranes that are not covered by a condom. Direct contact with an infectious lesion may therefore still result in transmission.

Condom use reduces risk but cannot eliminate it completely.

Key Takeaways

• Syphilis is caused by Treponema pallidum.
• Early syphilis may cause mild, painless, or temporary symptoms.
• A syphilis lesion may disappear even though the infection remains.
• Secondary syphilis can cause rashes, fever, swollen lymph nodes, and other nonspecific symptoms.
• Syphilis may enter a latent phase without visible symptoms.
• Testing should be considered after a possible exposure even when symptoms are absent.
• Early diagnosis allows appropriate antibiotic treatment and helps reduce further transmission.

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Source and Editorial Note

This article was adapted by the Healthology Editorial Team from Korean-language medical news material provided for publication.

The English version was independently edited for international readers and was not produced as a literal sentence-by-sentence translation.

Medical comments were provided by Dr. Min-Jong Lee, Goldman Urology Clinic Gangnam.