Syphilis is a sexually transmitted infection (STI), once responsible for devastating epidemics. It is caused by a bacterium called Treponema pallidum. The rate of primary and secondary syphilis in the United States declined by 89.2 percent from 1990 to 2000. The number of cases rose, however, from 5,979 in 2000 to 6,103 in 2001.
The U.S. Centers for Disease Control and Prevention reported in November 2002 that this was the first increase since 1990.
Of increasing concern is the fact that syphilis increases by 3- to 5-fold the
risk of transmitting and acquiring HIV (human immunodeficiency virus), the virus
that causes AIDS (acquired immunodeficiency syndrome).
HOW IS SYPHILIS TRANSMITTED?
The syphilis bacterium is very fragile, and the infection is almost always
transmitted by sexual contact with an infected person. The bacterium spreads
from the initial ulcer (sore) of an infected person to the skin or mucous
membranes (linings) of the genital area, mouth, or anus of an uninfected sexual
partner. It also can pass through broken skin on other parts of the body.
In addition, a pregnant woman with syphilis can pass T. pallidum to
her unborn child, who may be born with serious mental and physical problems as a
result of this infection.
WHAT ARE THE SYMPTOMS OF SYPHILIS?
The initial infection causes an ulcer at the site of infection. The bacteria,
however, move throughout the body, damaging many organs over time. Medical
experts describe the course of the disease by dividing it into four
stages-primary, secondary, latent, and tertiary (late). An infected person who
has not been treated may infect others during the first two stages, which
usually last 1 to 2 years. In its late stages, untreated syphilis, although not
contagious, can cause serious heart abnormalities, mental disorders, blindness,
other neurologic problems, and death.
The first symptom of primary syphilis is an ulcer called a chancre
(“shan-ker”). The chancre can appear within 10 days to 3 months after exposure,
but it generally appears within 2 to 6 weeks. Because the chancre may be
painless and may occur inside the body, the infected person might not notice it.
It usually is found on the part of the body exposed to the infected partner’s
ulcer, such as the penis, vulva, or vagina. A chancre also can develop on the
cervix, tongue, lips, or other parts of the body. The chancre disappears within
a few weeks whether or not a person is treated. If not treated during the
primary stage, about one-third of people will go on to the chronic stages.
A skin rash, with brown sores about the size of a penny, often marks this
chronic stage of syphilis. The rash appears anywhere from 3 to 6 weeks after the
chancre appears. While the rash may cover the whole body or appear only in a few
areas, it is almost always on the palms of the hands and soles of the feet.
Because active bacteria are present in the sores, any physical contact-sexual
or nonsexual-with the broken skin of an infected person may spread the infection
at this stage. The rash usually heals within several weeks or months.
Other symptoms also may occur, such as mild fever, fatigue, headache, sore
throat, patchy hair loss, and swollen lymph glands throughout the body. These
symptoms may be very mild and, like the chancre of primary syphilis, will
disappear without treatment. The signs of secondary syphilis may come and go
over the next 1 to 2 years of the disease.
If untreated, syphilis may lapse into a latent stage during which the disease
is no longer contagious and no symptoms are present. Many people who are not
treated will suffer from no further signs and symptoms of the disease.
Approximately one-third of people who have had secondary syphilis go on to
develop the complications of late, or tertiary, syphilis, in which the bacteria
damage the heart, eyes, brain, nervous system, bones, joints, or almost any
other part of the body. This stage can last for years, or even for decades. Late
syphilis can result in mental illness, blindness, other neurologic problems,
heart disease, and death.
HOW IS SYPHILIS DIAGNOSED?
Syphilis is sometimes called “the great imitator” because its early symptoms
are similar to those of many other diseases. Sexually active people should
consult a doctor or other health care worker about any rash or sore in the
genital area. Those who have been treated for another STI, such as gonorrhea,
should be tested to be sure they do not also have syphilis.
There are three ways to diagnose syphilis.
- Recognizing the signs and symptoms
- Examining blood samples
- Identifying syphilis bacteria under a microscope
The doctor usually uses all these approaches to diagnose syphilis and decide
upon the stage of infection.
Blood tests also provide evidence of infection, although they may give
false-negative results (not show signs of an infection despite its presence) for
up to 3 months after infection. False-positive tests (showing signs of an
infection when it is not present) also can occur. Therefore, two blood tests are
usually used. Interpretation of blood tests for syphilis can be difficult, and
repeated tests are sometimes necessary to confirm the diagnosis.
HOW IS SYPHILIS TREATED?
Unfortunately, the early symptoms of syphilis can be very mild, and many
people do not seek treatment when they first become infected.
Doctors usually treat patients with syphilis with penicillin, given by
injection. They use other antibiotics for patients allergic to penicillin. A
person usually can no longer transmit syphilis 24 hours after starting
treatment. Some people, however, do not respond to the usual doses of
penicillin. Therefore, it is important that people being treated for syphilis
have periodic blood tests to check that the infectious agent has been completely
People with neurosyphilis may need to be retested for up to 2 years after
treatment. In all stages of syphilis, proper treatment will cure the disease.
But in late syphilis, damage already done to body organs cannot be reversed.
WHAT ARE THE EFFECTS OF SYPHILIS IN PREGNANT WOMEN?
A pregnant woman with untreated, active syphilis is likely to pass the
infection to her unborn child. In addition, miscarriage may occur in as many as
25 to 50 percent of women acutely infected with syphilis during pregnancy.
Between 40 to 70 percent of women with active syphilis will give birth to a
Some infants with congenital syphilis may have symptoms at birth, but most
develop symptoms between 2 weeks and 3 months later. These symptoms may include
- Skin ulcers
- Weakened or hoarse crying sounds
- Swollen liver and spleen
- Yellowish skin (jaundice)
- Anemia (low red blood cell count)
- Various deformities
People who care for infants with congenital syphilis must use special
cautions because the moist sores are infectious.
Rarely, the symptoms of syphilis go undetected in infants. As infected
infants become older children and teenagers, they may develop the symptoms of
late-stage syphilis, including damage to their bones, teeth, eyes, ears, and
CAN SYPHILIS CAUSE OTHER COMPLICATIONS?
Syphilis bacteria frequently invade the nervous system during the early
stages of infection. Approximately 3 to 7 percent of persons with untreated
syphilis develop neurosyph