Brief overview
- Causes and risk factors: Bacterial infection that causes diseases of the genitourinary tract, respiratory tract, or eyes, depending on the Chlamydia species. Infection occurs, for example, through unprotected sexual intercourse, droplet infection, or via pets (birds)
- Symptoms: Depends on the chlamydia species. If infected, respiratory tract (e.g., sore throat, cough), conjunctivitis, burning during urination, purulent discharge from urethra and testicular pain (men), lower abdominal pain, vaginal discharge and bleeding (women), sometimes hardly any symptoms
- Treatment: antibiotics, e.g. azithromycin or doxycycline, ceftriaxone and metronidazole
- Diagnosis: Physical examination, pathogen detection by smear, urine test, blood test for pathogen or antibodies, ultrasound (if infection of the abdomen is suspected)
- Prognosis and course: Good with early treatment, without treatment complications in the respective organ system are possible.
- Prevention: Depending on the pathogen, to protect against Chlamydia trachomatis use of condoms, timely treatment of sick animals or hygiene in handling pets (birds)
What are Chlamydia?
Different species are important for chlamydial infections in humans:
Chlamydia trachomatis
Different serotypes cause three different clinical pictures in humans:
- Genitourinary tract diseases in men and women (sexually transmitted disease, STD)
- Trachoma, an eye disease
- Lymphogranuloma venorum, also a sexually transmitted disease
Chlamydia pneumonia
This pathogen primarily causes respiratory diseases, such as pharyngitis, sinusitis, or bronchitis.
Chlamydia psittaci
This form of chlamydial infection is also known to doctors as ornithosis, psittacosis, or parrot fever. It also causes respiratory illness, like pneumonia. People with close contact with birds have a higher risk of infection. Overall, psittacosis is relatively rare in Central Europe.
Chlamydia: Causes and risk factors
In order to multiply, chlamydiae must first enter a host cell, for example a mucosal cell. Inside the cell, the bacteria are present as reticular bodies: They are now no longer infectious, but carry out metabolism and are capable of division.
In the host cell, chlamydiae undergo a developmental cycle that lasts several days. At the end, they transform into elementary bodies. These are released from the host cell. The new elementary particles now infect neighboring cells or are transmitted to other individuals.
How does one become infected with chlamydia?
The way in which chlamydia is transmitted and contracted depends on the type of pathogen:
Transmission of Chlamydia trachomatis.
In Chlamydia trachomatis, serovars D to K and L1 to L3 are transmitted mainly through sexual intercourse.
Infection occurs through colonized mucous membranes and body fluids:
- urethra, vagina, penis, rectum
- body fluids such as vaginal secretions, urine and semen (also the “lust drop”)
Chlamydia transmission with serovars A to C occurs through infectious eye fluid. Infection with these chlamydiae is also possible via contaminated hands or textile products (such as towels or washcloths).
Chlamydial transmission by flies has also been observed in this subgroup. Therefore, the pathogen is widespread, especially in countries with poor hygienic conditions. Some people are concerned about contracting chlamydia in a public restroom. However, this is not considered a common route of infection. It is also not possible to transmit it through tongue kissing.
Transmission of Chlamydia pneumoniae
This bacterium is transmitted through the air and saliva. Like Chlamydia trachomatis, it accumulates and multiplies in human cells. Such chlamydiae are also found in some animals (such as koalas or horses). However, routes of infection to humans are not known here.
Transmission of Chlamydia psittaci
The main sources of infection for humans include turkeys, ducks, parrots and pigeons. It is possible for them to contract Chlamydia psittaci while being completely symptom-free. Especially in pet birds, the bacterium sometimes settles for a long time without causing disease.
Chlamydia is transmitted to humans via the feces and feathers of infected animals. In some cases, mere contact can also lead to chlamydial infection. Chlamydia can also be found in liquid secretions from the beak or respiratory tract of birds.
Chlamydia psittaci is not known to be transmitted from person to person.
Chlamydia: incubation period
Chlamydia infects the mucous membranes of the genital and anal regions as well as the respiratory tract. The time between infection and onset of disease is called the incubation period. For Chlamydia trachomatis, it is one to three weeks. For Psittaci and Pneumoniae strains, it is about one to four weeks.
Independent of this is the duration of the infectiousness of chlamydia. However, since many infections remain asymptomatic, it is almost impossible to determine.
Different types of chlamydia are transmitted in different ways. Therefore, different risk factors of infection also apply:
Chlamydia trachomatis: Risk factors
For sexually transmitted chlamydia (Chlamydia trachomatis D-K and L1-L3), the following main transmission routes are considered risk factors:
- Oral intercourse
- Vaginal intercourse, especially unprotected (= without condom)
- Anal intercourse, especially unprotected
- sharing of contaminated and unprotected sex toys
Anyone who is already infected with the HI virus (HIV) has an increased risk of also becoming infected with chlamydia. The AIDS pathogen weakens the human immune system. This makes it more difficult for the immune system to fight chlamydia and other pathogens.
Conversely, in the case of a chlamydia infection, the risk of also becoming infected with HIV is increased: The inflamed mucous membrane cells in the intimate area are an ideal entry point for the HIV virus.
A risk factor for conjunctivitis caused by Chlamydia trachomatis A-C (trachoma) is primarily poor hygiene with a low standard of living. The infection therefore occurs particularly in countries with poor hygiene conditions.
Chlamydia pneumoniae: risk factors
Bacteria of this genus are widespread worldwide. In Central Europe, too, experts assume that the population is highly contaminated. Probably everyone has contact with Chlamydia pneumoniae at least once in their life.
There are no special risk factors for chlamydia transmission. As with most infectious diseases, the risk of infection is increased by a weak immune system, increasing age, and direct contact with infected persons.
Chlamydia psittaci: risk factors
In the case of Chlamydia psittaci, there is a risk of infection especially for bird breeders and dealers as well as pet bird keepers. Even desiccated bird feces and feathers are contagious for up to four weeks. If infected birds are not treated, about ten percent of them develop into chronic but symptomless carriers.
Chlamydia infection: symptoms
In addition, certain chlamydiae affect the eye, lungs and, in severe cases, other organs.
In total, there are three chlamydia species that cause disease in humans:
- Chlamydia trachomatis
- Chlamydia (Chlamydophila) psittaci
- Chlamydia (Chlamydophila) pneumoniae
Symptoms caused by Chlamydia trachomatis
There are several subgroups (serovars) of the Chlamydia trachomatis bacterium that cause various diseases:
- Trachoma: chlamydial signs in the eye; caused by serovars A to C.
- Infections of the urinary and genital organs (urogenital infections), conjunctivitis: caused by serovars D to K
- Lymphogranuloma venereum: venereal disease; caused by serovars L1 to L3
In addition to specific symptoms, as with many other infections, there is a possibility of flu-like symptoms such as fever, headache, and aching limbs. In addition, some patients with chlamydia complain of fatigue and weakness throughout the day.
Trachoma
In poor hygienic conditions, patients repeatedly become reinfected with chlamydia. In addition, there is a risk of other bacteria “sitting on top” of the inflammation (superinfection). Both lead to the follicles enlarging and agglomerating into so-called granulomas.
The inflammation, which has become chronic, causes the inner mucous membrane of the eyelids to shrink in a scar-like manner. As a result, the edges of the eyelids with their lashes bulge inward and irritate the cornea of the eye through small injuries (trichiasis). This becomes inflamed (keratitis) and increasingly cloudy. Without treatment, there is a risk of blindness in extreme cases.
Urogenital symptoms in men
Serovars D to K cause urogenital infections. The first signs of chlamydia-infected urinary and genital organs in men usually affect the urethra: it becomes inflamed (urethritis). The patient experiences a feeling of pressure and painful burning when urinating. In some circumstances, chlamydia causes redness of the glans at the urethral outlet and discharge of pus from the urethra.
However, many infected men do not show any symptoms at all due to chlamydia. Doctors then speak of an asymptomatic infection.
Urogenital symptoms in women
In women, infection with Chlamydia trachomatis D-K usually leads to inflammation of the cervix (cervicitis) and/or the urethra (urethritis). Some women wonder what the first signs of chlamydia infection are: A possible chlamydia sign in cervicitis is mucopurulent, often strong-smelling discharge of a yellowish color. Urethritis due to chlamydia is accompanied in many cases by frequent urination and pain or problems urinating, similar to bladder infections.
However, most women with chlamydia-related cervicitis and/or urethritis have no symptoms at all. It is therefore impossible to say how long someone has a chlamydial infection without noticing it. Often the infection remains unnoticed for years and is therefore not treated. This increases the risk of infection: If the bacteria continue to rise, the inflammation spreads to the endometrium, fallopian tubes and ovaries.
In severe cases, there is a risk of serious late effects. These include chronic lower abdominal pain and infertility. Experts estimate that every second case of infertility is due to a chlamydia infection. It also increases the risk of the fertilized egg implanting outside the uterus during pregnancy (extrauterine gravidity such as ectopic pregnancy).
How long it takes for infertility to occur after a chlamydial infection is difficult to say. In retrospect, it is usually impossible to determine exactly when the infection occurred.
In some women, the pelvic inflammatory disease spreads to the peritoneum (peritonitis). Sometimes the liver capsule then becomes inflamed (perihepatitis = Fitz-Hugh-Curtis syndrome). Possible chlamydia symptoms in this case are:
- Fever and fatigue
- Right-sided upper abdominal pain
- Pressure pain in the liver
The pain sometimes radiates to the right shoulder. Sometimes the inflammation spreads to the tissue adjacent to the appendix (periappendicitis).
Symptoms in man and woman
Chlamydia-related pharyngitis is characterized by a reddened throat, sore throat and painful swallowing. In addition, the germs sometimes affect the eye and cause conjunctivitis there.
Symptoms in pregnant women and newborns
An infection with Chlamydia trachomatis during pregnancy has the same consequences as in non-pregnant women. These include inflammation of the cervix and/or endometrium. This increases the risk of premature birth, premature rupture of the membranes and other pregnancy complications.
There is also a risk that the bacteria will be passed on to the baby at birth. The risk of this is 50 to 70 percent. A typical chlamydia symptom in the newborn is usually conjunctivitis, more rarely otitis media. If vaginal fluid gets into the baby’s respiratory tract, there is a risk of severe pneumonia.
During the puerperium, some infected mothers develop inflammation of the endometrium (postpartum endometritis).
Lymphogranuloma venereum
In some cases, the lymph nodes rupture and pus oozes out. Connective tissue scars form during healing. In addition, the lymph vessels sometimes become clogged. The lymph then no longer drains properly and becomes congested. As a result, the genitals become extremely enlarged (elephantiasis).
General chlamydia symptoms in this disease are fever, headache, muscle and joint pain.
Anal intercourse causes infection of the rectum. The lower sections of the intestine become inflamed (proctosigmoiditis). Affected individuals have mucous-bloody discharges, cramps during defecation (tenesmus), and fever. In some cases, abscesses and fistulas form in the rectal area. After healing, scarring strictures often develop in the rectum.
Symptoms due to Chlamydia psittaci
Chlamydia (Chlamydophila) psittaci causes a disease called ornithosis (psittacosis or bird disease). It manifests as a flu-like infection or as atypical pneumonia. Atypical is pneumonia that is not caused by the most common pathogen (streptococcus).
In severe cases, this chlamydial infection spreads to other organs, for example to the heart muscle. This then leads to inflammation of the heart muscle (myocarditis).
Some people who become infected with Chlamydia psittaci do not develop any symptoms of the disease at all.
Symptoms caused by Chlamydia pneumoniae
The pathogen Chlamydia (Chlamydophila) pneumoniae infects the respiratory tract and causes inflammation. For example, inflammation of the sinuses (sinusitis), pharyngitis or bronchitis occur. Sometimes the chlamydia infection leads to atypical pneumonia.
Depending on the site of inflammation, the following chlamydia signs occur:
- Sore throat
- Difficulty swallowing
- Chest pain
- Headache
- Fever
- Cough
Chlamydia infection: treatment
The choice of chlamydial antibiotics and their dosage depend, among other things, on the clinical picture (trachoma, urogenital infection et cetera). For women, consideration is given to whether they are pregnant or breastfeeding. In addition, the doctor pays attention to possible additional infections when planning the therapy.
Chlamydia infection does not heal by itself – therapy by the doctor is always required.
Treatment of Chlamydia trachomatis infections
Chlamydia treatment for this type of pathogen depends primarily on the clinical picture.
Those who are infected with chlamydia but do not show any symptoms are usually given doxycycline: the infected person takes 100 milligrams of the antibiotic twice a day for seven days. In certain cases, a single dose of 1.5 grams of azithromycin is an alternative.
Chlamydia treatment for urogenital inflammation
Acute urethritis caused by chlamydia is also preferably treated with doxycycline (100 milligrams twice daily for seven days) in men and nonpregnant women. The same usually applies to acute prostatitis and cervicitis caused by chlamydia.
If the inflammation has spread to the fallopian tubes and/or ovaries in women, a “pelvic inflammatory disease” (PID) is present. In this case, the doctor will prescribe a combined chlamydia therapy consisting of several antibiotics (ceftriaxone, doxycycline, metronidazole). But how long does it take for the chlamydia to go away? And how long is one contagious after treatment with antibiotics? The duration of treatment is one to two weeks, depending on the course of the disease.
Usually, chlamydia is no longer detectable afterwards, which means that the person in question is no longer infectious. To ensure this, the chlamydia treatment is followed up with a test. In all urogenital chlamydia infections, the sexual partner must also be treated. This prevents couples from repeatedly re-infecting each other with chlamydia.
Chlamydia treatment for lymphogranuloma venereum
Chlamydial venereal disease is usually treated with doxycycline. Patients take 100 milligrams of the antibiotic twice a day for 21 days.
Chlamydia treatment during pregnancy and breastfeeding.
If pregnant or breastfeeding women suffer from a genital chlamydial infection, the doctor prefers to prescribe azithromycin: the patient then takes a single dose of the antibiotic.
Alternatively, the doctor also prescribes erythromycin for chlamydia therapy. This antibiotic must be taken for one to two weeks, depending on the dose.
The patient’s sexual partner must also be tested for chlamydia and treated.
Chlamydia treatment in newborns
Babies who contract Chlamydia trachomatis from their infected mother during birth are usually given erythromycin for a period of 14 days.
Alternatively, chlamydia treatment in newborns is done with azithromycin. Sometimes a single dose is sufficient here. In other cases, the antibiotic is given for three days.
Chlamydia treatment for rectal or pharyngitis
If the patients suffer from the venereal disease gonorrhea (gonorrhea) at the same time, the doctor chooses a combination therapy: he prescribes the two antibiotics ceftriaxone and azithromycin.
Chlamydia treatment for eye infections
Chronic conjunctivitis and corneal inflammation caused by serovars A to C of Chlamydia trachomatis is called trachoma. Chlamydia therapy here usually consists of taking 1.5 grams of azithromycin once. Alternatively, the doctor prescribes the antibiotic for local application (for example, as an ointment) over several days.
Conjunctivitis caused by chlamydial serovars D to K is also treated with a single dose of 1.5 grams of azithromycin. There are other options for chlamydia therapy, for example, a lower dose of azithromycin or doxycycline. It is taken for several days. Alternatively, local azithromycin treatment may be considered.
Chlamydia treatment for other pathogens
Chlamydia treatment for infection with Chlamydia psittaci or Chlamydia pneumoniae generally consists of doxycycline: patients take the antibiotic for ten to 21 days.
Infections with Chlamydia psittaci are reportable.
Chlamydia treatment: Further tips
Depending on the clinical picture, antibiotic chlamydia treatment can be supported by other measures.
For example, in the case of urogenital chlamydial infection and lymphogranuloma venereum, doctors recommend abstaining from sexual intercourse during treatment. This also applies to oral sex during chlamydia treatment.
If the partner has tested negative for chlamydia, it is important to wait until the end of the entire treatment period before having sexual intercourse – otherwise there is a risk of infecting the partner.
Especially in the case of severe urogenital infections, the doctor recommends rest and bed rest for some time – in addition to therapy with antibiotics.
Chlamydia symptoms of epididymitis or testicular inflammation can often be alleviated by elevating the testicles. For this purpose, a “testicle bed” made of a rolled-up towel, for example, is suitable. It is also advisable to cool the testicles, for example with cold, moist compresses.
Ask your doctor how you yourself can best effectively support chlamydia treatment with medication!
Chlamydia infection: examinations and diagnosis
If you suspect that your urinary or genital organs are infected with chlamydia, see a doctor: For men, urologists, and for women, gynecologists (women’s health specialists) are the right people to contact. A dermatologist is also a suitable specialist for skin and sexually transmitted diseases.
For a chlamydia-related respiratory illness (such as pneumonia), the family doctor should be the first port of call. In the case of a chlamydial infection of the eye, it is advisable to consult an ophthalmologist.
Medical history (anamnesis)
The doctor will first talk to you and take your medical history. He will ask, for example, about typical symptoms and any previous illnesses. If a chlamydia infection in the intimate area is suspected, information about sexual habits is also significant. Possible questions are:
- Have you noticed any unusual discharge from your urethra/vagina? If so, what does it look like?
- Do you feel pain or a burning sensation when you urinate?
- Do you change your sexual partner more often?
- Have you had unprotected sexual intercourse recently?
- Do you have any other pain, for example in the abdominal and pelvic region?
- Have you noticed any swellings in the testicle or groin area?
If you also suffer from sore throat and swallowing pain, chlamydia transmission through oral sex may have occurred. Answer your doctor openly to appropriate inquiries, even if this may make you uncomfortable. This is the only way to determine the exact cause of your symptoms.
Trachoma occurs mainly in tropical countries. Therefore, if you have eye pain or redness, you will be asked about past travels.
In the case of respiratory symptoms, the doctor will ask about the exact symptoms and any contact with birds:
- Do you have a cough? Is this dry or with sputum?
- Are you suffering from chills or fever?
- Do you feel fatigued?
- Do you work with or keep birds?
Physical examination
He will tap, palpate and listen to the abdomen. Inflammation of the internal female reproductive organs is sometimes felt by the doctor as a swelling under the abdominal wall. If he presses on the right upper abdomen, stabbing pain indicates a chlamydial infection of the liver capsule.
To detect a chlamydial infection of the respiratory tract, the physician taps the lungs (percussion) and uses the stethoscope to assess the airways (auscultation). If there are throat and swallowing problems, a reddened throat often indicates an inflammation of the mucous membranes (pharyngitis).
If a chlamydial infection of the eye is suspected, the physician examines it in detail for redness or inwardly turned eyelids (entropion).
Imaging procedures
Imaging studies such as computed tomography (CT) or ultrasound (sonography) are not usually necessary for chlamydial infection.
However, Chlamydia trachomatis bacteria sometimes penetrate upward into the abdomen, especially in women. The doctor recognizes abscesses or other swellings due to inflammation of the fallopian tubes and ovaries (adnexitis) in the ultrasound image.
Chlamydia test
There are different types of chlamydia tests: direct methods are intended to detect the pathogen itself in sample material from the patient. Indirect methods include a blood test, looking for antibodies to chlamydia in the blood. Chlamydia self-tests are available online, but the diagnosis of a chlamydia infection belongs in the hands of the doctor.
Direct detection of the bacteria
A chlamydia test for direct detection of bacteria is used to test for suspected infection and confirm the diagnosis. There are quite different test procedures, which differ in terms of their significance and possible applications.
For example, a swab taken by the doctor from the cervical mucosa, the urethra or the rectum is used to detect chlamydia. There is also a chlamydia urine test. This rapid chlamydia test is particularly suitable in men for detecting a urogenital infection.
For infections of the eye, eye secretion (secreted fluid) is examined.
To detect chlamydia in the sample material, the pathogens are cultivated in a cell culture. However, this can be difficult and, for safety reasons, is only possible in specialized laboratories.
Alternatively, certain structural components of the bacteria can be detected, for example characteristic proteins on the surface of the germs. Some rapid Chlamydia tests are also based on such antigen tests.
Another possibility is the detection of the chlamydial genome in the sample material. For this purpose, so-called nucleic acid amplification tests (NAAT) are usually performed. Today, they are considered the method of choice.
Detection of antibodies
The immune system reacts to an infection with Chlamydia by producing specific antibodies. However, it sometimes takes several weeks before these can be detected in the patient’s blood. Such a serological chlamydia test is therefore generally not suitable for detecting an acute infection.
A serological chlamydia test therefore makes sense primarily for clarifying an ascended (complicated) chlamydia infection. The doctor also takes a blood sample and tests it for chlamydia antibodies to determine the cause of infertility. This is because a late consequence of chlamydia infection is infertility.
Costs
In Germany, women up to the age of 25 can take a chlamydia screening test at their gynecologist once a year free of charge. For this chlamydia screening, a urine sample from the patient is tested for Chlamydia trachomatis. The costs for this are covered by the statutory health insurance funds.
Women who wish to be tested for chlamydia after the age of 25 as a precautionary measure must bear the costs themselves. The same applies to men of all ages. An exception is made in the case of a chlamydia test prescribed by a doctor: men and women are then examined and tested free of charge.
A chlamydia test is carried out during pregnancy as part of the preventive medical check-ups.
Test also for sexual partners
Chlamydia infection: course of the disease and prognosis.
With timely and consistent treatment, a chlamydia infection can generally be cured without consequences. However, many chlamydial infections initially remain undetected because they cause hardly any symptoms. This is especially true of a chlamydial sexually transmitted disease: infected persons are thus an unwitting source of infection for sexual partners.
Chlamydia: complications
If left untreated, chlamydial infection is at risk of becoming chronic and causing complications:
Infertility and Extrauterine Pregnancy.
In some cases, a urogenital infection rises in the body: In men, for example, this results in inflammation of the testicles and epididymis. Untreated patients are at risk of becoming infertile.
In women, a urogenital chlamydia infection spreads to the pelvis and leads to inflammation of the fallopian tubes and ovaries. As a result, these sometimes become stuck together and scarred. This increases the risk of infertility and of pregnancies outside the uterus (extrauterine pregnancy), such as tubal or abdominal pregnancy.
Reactive arthritis (Reiter’s syndrome).
In rare cases, inflammation of the urethra by Chlamydia trachomatis results in reactive arthritis. This form of joint inflammation used to be called Reiter’s disease or Reiter’s syndrome. For historical reasons, however, these terms have since been abandoned. Reactive arthritis occurs primarily in men.
Most patients present with three symptoms (formerly called the “Reiter’s triad”): non-purulent ureteritis, painful joint inflammation (knee, ankle, et cetera), and conjunctivitis.
Other possible signs of chlamydia are skin rashes, for example in the genital area, in the mouth, or on the mucous membrane of the mouth and on the soles of the feet. Complications such as inflammation of the heart muscle (myocarditis), pleura (pleurisy) and aorta (aortitis) are also possible.
Other complications of chlamydia
Very rarely, infection with Chlamydia pneumoniae leads to inflammation of the heart (myocarditis and endocarditis). Complications such as painful nodular skin redness (erythema nodosum), reactive arthritis or inflammation of the spinal cord nerves or meninges (meningoradiculitis) are also observed only occasionally.
Chlamydia infection in newborns
About 50 to 70 percent of infected pregnant women transmit chlamydia to the baby during vaginal delivery. As a result, the newborn usually develops conjunctivitis and/or pneumonia. The latter is accompanied in many cases by otitis media.
Preventing chlamydia
To prevent a sexually transmitted chlamydia infection, you should always use a condom during sexual intercourse. This applies to both vaginal and anal intercourse. You should also use a condom or a “lick cloth” (dental dam) during oral sex to protect against infection. Despite the use of a condom, the risk of infection with chlamydia cannot be ruled out one hundred percent, but the risk is significantly lower.
Conjunctivitis caused by Chlamydia trachomatis (trachoma) is the most common eye disease worldwide and the second most common cause of blindness. It is particularly prevalent in countries with poor hygiene standards. Anyone traveling in such countries should therefore pay particular attention to hygiene.
There are no special preventive measures for Chlamydia pneumoniae. Persons at risk, such as the chronically ill, elderly or immunocompromised, should avoid contact with infected persons.
To avoid contracting ornithosis, avoid contact with birds infected or suspected of being infected with Chlamydia psittaci. Protection against infection is provided by protective clothing, mouth and nose protection. This is because chlamydia is already transmitted through contact with contaminated, polluted dust.
