Lyme disease (or Lyme disease) is an infection caused by the bacterium Borrelia burgdorferi and is transmitted to humans through the bite of an infected tick.
Borrelia burgdorferi is a species of bacteria also called spirochetes.
The cause of Lyme disease is a tick bite.
In the United States, Lyme disease is caused by deer ticks.
In Europe, the ticks that cause this disease are mainly found on sheep.
The ticks are:
- not larger than 1 cm.
It is therefore almost impossible to see these small animals.
To get this disease, the infected tick must bite humans.
- are introduced into the skin through the bite,
- enter the blood circulation.
In most cases, the tick must remain for 36-48 hours to transmit Lyme disease.
If you see a tick filled with blood, you can assume that it has transmitted the microbes to humans.
The earliest possible removal of the tick can prevent infection.
In the United States, the frequency of reported cases is about 5 per 100,000 population.
In Europe, data vary greatly from country to country. On average, about 85,000 cases are reported each year across the European continent.
Is Lyme disease contagious?
Lyme disease is transmitted to humans through the bite of the carrier tick.
Lyme disease is not contagious and is not transmitted from an infected person to a healthy person.
One can also not be infected by mosquitoes, flies, fleas, etc.
The only source of infection is the tick bite.
There is no evidence that transmission of Lyme disease from mother to child is possible during pregnancy.
The disease is not transmitted from the mother if the child is breastfed at the breast.
To date (2017), no cases have been reported.
Some doctors recommend assisted breastfeeding, as a precautionary measure to avoid “poisoning” the child by antibiotics.
Pregnant women can burden their unborn child with antibiotics, because these drugs can harm the fetus.
The incubation period can vary between 4 and 25 days.
Signs and symptoms of Lyme disease
This condition affects several body systems and can cause various symptoms.
Infection is usually divided into three phases:
1) local infection, 2) diffuse or spread in the body,
3) late or persistent infection.
Symptoms of local infection (stage 1)
A rash develops annular and expands outwards; Characteristics:
- diameter between 5 and 50 cm,
- overheated skin, hardened in the middle area,
- the outer edge is red and shiny.
One observes a brighter zone in the center, which gives the characteristic appearance of an ox’s eye.
The first symptom is this rash called erythema migrans (wandering redness); It causes:
- overheated skin,
- Itching (rare).
Erythema usually appears in the area of the tick puncture site; Frequently affected are:
Symptoms of diffuse infection or scattering phase (stage 2)
These may also be the first symptoms, the wandering redness does not develop in every patient.
The bacterium enters the blood circulation a few days after local infection and this passage marks the beginning of the second phase: “diffuse infection”.
At this stage, erythema migrans can develop throughout the body, along with:
- muscle pain and joint pain,
- neck stiffness,
- photophobia (photosensitivity),
- nausea and vomiting,
- enlarged lymph nodes,
- muscle contractures,
The signs of the second phase can easily be confused with the symptoms of influenza.
The infected person may also develop encephalitis, which is accompanied by:
- Sleep disorder
Gradually, the infection spreads to other parts of the body:
If the disease is not treated, the infected person can develop complications in these organs.
Late or persistent symptoms (stage 3)
The final stage is characterized by some symptoms, including:
- chronic encephalitis,
- memory, sleep and concentration disorders,
- mental confusion,
- neurological symptoms such as cognitive impairment,
- meningitis (meningitis),
- paralysis of the facial muscles,
- Leg weakness.
Eventually, structures of the heart can become inflamed, resulting in:
- abnormal heart rhythm,
If the disease affects the joints, the person may suffer from:
- Joint stiffness.
Diagnosis of Lyme disease
The signs and symptoms of Lyme disease are non-specific and are often found in other conditions, so diagnosis can be difficult.
Furthermore, ticks that transmit Lyme disease can also transmit other diseases at the same time.
Most people suffering from this disease do not remember the tick bite.
If there is no typical rash, the doctor can further question the anamnesis in detail, because he must know whether the patient has often been outdoors in places where Lyme disease occurs frequently.
This is followed by a physical examination.
The blood tests are used to identify antibodies and can be performed to confirm the diagnosis. These tests are all the more reliable if they are carried out a few weeks after the onset of infection, as the body has had time to produce antibodies.
Blood test with antibody-based detection method “ELISA”
The test most commonly used to diagnose Lyme disease is called ELISA (Enzyme Linked Immunosorbent Assay) and detects the antibodies of B. burgdorferi.
Since there are sometimes false-positive results, it is not used as the only evidence for the diagnosis.
This test cannot be positive as long as the initial phase of Lyme disease is present, but the rash is very classic to make the diagnosis without further examination of the persons living in a tick area.
Western blot or immunofixation test
If ELISA is positive, this test is used to confirm the diagnosis.
Polymerase chain reaction (PCR). This test is used to detect bacterial DNA in the fluid of the infected joint.
In detecting infections in blood or urine, the test is not as effective.
It is used in people who may have tardive Lyme arthritis.
The doctor must exclude the diseases that cause similar symptoms, for example:
- Polymorphic erythema
- Erythema annulare centrifugum
- Rheumatic diseases
- Guillain-Barrè syndrome
- Bell’s palsy
- Multiple sclerosis
- Other diseases caused by tick bites, such as rickettsiosis and tick-borne encephalitis (TBE).
Treatment of Lyme disease
Antibiotics are used to treat Lyme disease.
As a rule, with early therapy, recovery occurs faster and more completely.
Which antibiotics are recommended?
1. Oral antibiotics. This is the standard therapy in the initial phase of Lyme disease.
The following are used:
- doxycycline for adults and children of at least 8 years of age,
- Amoxicillin or cefuroxime in adults, children and pregnant or lactating women.
Usually, an antibiotic cycle of 14-21 days is recommended, but some studies indicate that cycles lasting 10-14 days are just as effective.
2. Intravenous antibiotics. If the central nervous system is involved by the disease, the doctor may advise therapy with an intravenous antibiotic for 14-28 days.
This is effective for clearing the infection, although more time may be needed to clear the symptoms.
Intravenous antibiotics can cause various side effects, including:
- decreased leukocyte count,
- mild to severe diarrhoea,
- Infection by other antibiotic-resistant organisms not related to Lyme disease.
After treatment, some people continue to suffer from symptoms, for example:
The cause of these symptoms is unknown and treatment with antibiotics does not help.
Some experts suggest that some people who have Lyme disease have a predisposition to develop an autoimmune response that contributes to the symptoms. Further scientific studies are still needed.
Prognosis for patients with Lyme disease
In general, the prognosis is very good if treatment with antibiotics is carried out.
Cure can be achieved at the end of antibiotic treatment, which clears the infection, but symptoms may persist for a long time.
Untreated Lyme disease can lead to serious complications up to death.
Prevention of Lyme disease
In 2013, tests began on a promising vaccine against this disease, which has no serious side effects.