chickenpox

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Classification according to ICD-10
B01.- Varicella [chickenpox]
B01.0 † Varicella meningitis (G02.0 *)
B01.1 † Varicella encephalitis (G05.1 *)
B01.2 † Varicella pneumonia (J17.1 *)
B01.8 Varicella with other complications
B01.9 Varicella without complications
ICD-10 online (WHO version 2019)

The chickenpox or varicella (obsolete and varicella ) are a by droplet infection transmitted infectious disease caused by the varicella zoster virus is triggered. Other names for chickenpox chickenpox , Spitz pox , top-pox , Wild smallpox , especially in Austria Feuchtblattern , sheep platters or chicken pox . The name chickenpox is based on the transmission of this disease through the "wind" (the viruses are also transmitted over a few meters in the air). Chickenpox must be distinguished from smallpox (variola), a dangerous infectious disease caused by viruses of the genus Orthopoxvirus .

Chickenpox mainly affects children of preschool age and subsequently leads to lifelong immunity in the majority of those infected , which is why it is also one of the childhood diseases . The main symptoms are fever and a characteristic, itchy rash with water-clear blisters. It can complications in the form of cerebellar or brain inflammation , a pneumonia or bacterial superinfection of the skin occur.

Since it is a viral infection , treatment is usually symptomatic. In special cases - for example in immunosuppressed patients - a virostat can be used. After the symptoms have subsided, varicella viruses remain in the spinal or cranial nerve ganglia and can be reactivated from here in the form of shingles ( herpes zoster ).

For prophylaxis there is a vaccination that has been generally recommended in Germany since July 2004. A multiple vaccine against measles, mumps, rubella and chickenpox has also been available since August 2006 . Also, a post-exposure prophylaxis with passive vaccination or antiviral drugs is possible.

Chickenpox is notifiable in Germany.

frequency

Before the generally recommended vaccination, chickenpox was the most common vaccine-preventable disease with 750,000 cases per year across Germany and peak incidence in childhood. More than 90% of all adolescents were infected by the age of 14. Herpes zoster usually occurred after the age of 40. Herpes zoster was much rarer in children: on average, only one out of 1000 children developed herpes zoster after 5 ± 2.5 years.

There is an accumulation of diseases in winter and spring.

Pathogen

Varicella zoster virus ( TEM image)

The causative agent of chickenpox is the varicella zoster virus (VZV), which according to the virus taxonomy is also referred to as human herpes virus 3 (HHV-3). The only known reservoir is humans. This virus is an enveloped , double-stranded DNA virus (dsDNA) and belongs to the Herpesviridae family , the Alphaherpesvirinae subfamily and the Varicellovirus genus . All viruses in this family enclose their DNA in an icosahedral capsid , a protein shell made up of triangular surfaces . The varicella zoster virus is spread all over the world and is already transmitted in childhood. As an example, the prevalence of antibodies against VZV in children in Sweden between 9 and 12 years of age rose from around 50% in the late 1960s to 98% in 1997, which is attributed to the increasingly widespread vaccination. In the adult population in Central Europe, antibodies are detectable in around 93 to 96%.

The chickenpox disease caused by the pathogen as the first infection of the VZV is very rarely fatal; this can occasionally occur without previous illness in patients with an intact immune system , but more frequently in immunodeficient and pregnant women. This also shows that the VZV is very strongly adapted to humans as its only host and that it can therefore be classified as “host-specific and partially adapted”. After an infection, it always remains as a DNA ring in the nucleoplasm of the nerve cells of the spinal or cranial nerve ganglia for life .

transmission

The highly contagious viruses are partly transmitted through direct contact with the varicella or zoster vesicles. The droplet infection, i.e. direct inhalation of exhalation droplets (expiratory droplets) of infected people, is possible one to two days before the rash breaks out . It is possible that the varicella zoster virus is transmitted through the air (“wind” pox). Since the pathogens “fly” a few meters in the air and are able to survive, infection via the air is possible even if there is no direct contact. Transmission through clothing or toys lying around is generally not to be feared. An exposure is sure always to be assumed if in immunocompetent the contact has lasted longer than an hour people in immunocompromised persons is to start from a minimum of ten minutes.

After exposure to the virus, more than 90 out of 100 susceptible (previously seronegative ) people become infected with this virus and then become ill, and they visibly develop chickenpox.

Chickenpox is contagious two days before the rash appears and remains so for five to ten days after the first blisters form or until the last blister has crusted over. The opinion that the infectiousness is present until the last crust falls off is considered outdated. During this time, the sick person should not come into contact with others, especially not with people at risk such as immune incompetents ( cortisone treatment , AIDS , cancer patients , neurodermatitis sufferers , the elderly) or women who are in the 8th to 21st week of pregnancy the latter poses a risk to the unborn child and also to the mother. If the mother had chickenpox between seven days before and three days after giving birth, she could be fatal. (See also Chickenpox in Pregnancy )

A nest protection in neonates and infants immune mothers due to transfer of IgG antibodies is sure three months after the susceptibility increases with the children from the sixth month of life, there is no nest protection more effect nine months can be vaccinated are performed.

Disease emergence

Due to the strict host specificity of VZV, earlier pathogenetic concepts had to be based on clinical observations and studies of the smallpox virus as an animal model . It was assumed that after penetration via the mucous membrane of the upper respiratory tract, a first virus replication initially takes place in the lymphoid tissue of the pharynx with a subsequent monocytic viraemia . Only after a second replication phase in the reticuloendothelial organs ( liver , spleen ) did the pathogens enter the skin with a secondary viraemia. The infection of the sensitive nerve cells, in whose ganglia the viruses subsequently survive for life, occurs either from the skin lesions or via the bloodstream. The long incubation period was well explained by this concept . There are now studies on mice with severe immunodeficiency who have been transplanted with human T cells , skin and nerve tissue. The results suggest that immediately after the first replication in regional lymph nodes of the pharynx, the viruses reach the skin in a T-cell-bound manner via the bloodstream. The long time between infection and the onset of the rash is explained by the fact that VZV must first overcome innate, very effective defense mechanisms that were previously unknown. This includes α-interferon production anchored directly in the cells of the epidermis .

Clinical manifestations

Chicken pox in children

Toddler with chickenpox
Vesicles
Typical distribution pattern of the rash in chickenpox compared to real smallpox. In chickenpox, the rash is more trunk-dominated.

After an incubation period of 10 to 21 (usually 14 to 17) days, mild and short-lasting fever as well as headache and body aches may occur. The next day, lentil-sized, sometimes itchy red spots develop in the area of ​​the trunk and face , but typically also the hairy head, later on the limbs, which later develop into nodules , in the center of which vesicles the size of rice grains develop within hours to a maximum of days form. These are often dented. The mucous membranes in the area of ​​the mouth (especially visible on the palate as yellowish erosions ), the nose , the eyes , and the skin of the genitals and anus can also be affected less frequently . The vesicles will eventually burst and a light brown crust will form. Since the lesions do not arise at the same time, the skin manifestations are manifold at a given point in time, so that one often speaks of an image similar to a “starry sky” that enables a diagnosis to be made.

The course of the disease is usually benign and usually lasts three to five days. The crusts fall off without scarring, provided the child does not scratch and the skin lesions remain limited to the epidermis.

Usually a person can only get chickenpox once in a lifetime, so after going through the disease once they are immune. However, there are exceptions, namely when the first occurrence of chickenpox occurred very easily and very early in childhood and thus insufficient antibodies could not be formed.

Chickenpox in adults

Man with chickenpox

Initial infection with the varicella zoster virus in adulthood ( Varicellae adultorum , the 'adult chickenpox') is rather rare due to the high level of infection and usually has a more severe disease course than in children. Complications with meningoencephalitis , lung ( pneumonia ) and liver inflammation ( hepatitis ) are possible. In adults, for example, there are usually significantly more efflorescences. The entire trunk, hairy head, face, legs, arms, and genitals can be affected. New smallpox keeps appearing for around a week, and up to four weeks in some adults. They first appear as red dots, which then fill with liquid, then fester and either crust directly or burst open beforehand. The fever can rise to over 40 degrees and usually occurs before the first red dots, together with a general feeling of illness.

In adults, particular attention must be paid to complications, as meningitis , pneumonia or gastrointestinal complications can occur here. To clarify meningitis, it should be checked whether the chin can be lowered onto the chest without pain (test for meningism ). If there are breathing difficulties or expectoration from the lungs, an X-ray of the chest must be made immediately to rule out pneumonia. Severe abdominal pain and a bloated stomach indicate complications in the gastrointestinal tract.

In order to achieve immunization through the usually harmless course of the disease in childhood, u. a. in the United States and the United Kingdom of Impfgegnern called pox parties (smallpox parties) held to specifically induce infections in children with chickenpox (see also: →  pox party ).

Complications

In about 5.7% of the chickenpox cases there are more or less serious complications. Due to the existing vaccination programs, however, the hospitalization rate is now low: only 2.5 to 7 out of 100,000 residents in Germany have to be admitted to hospital every year because of varicella.

The most common complications are bacterial superinfections, mostly caused by staphylococci , such as pneumonia (in adults 0.2 to 0.3%), a coordination disorder caused by the cerebellum ( ataxia ) or a bacterial body-wide infection ( sepsis ) originating in the skin (in children 2–3 /10,000). Other serious complications include Reye's syndrome , encephalitis or meningitis - inflammation of the brain or meninges - as well as inflammation of the liver (hepatitis) or joint problems . Another rare complication caused by chickenpox is changes in blood vessels ( angiopathy ), which can lead to strokes . In a Swiss study, a mortality rate of 1 in 100,000 cases of non-vaccinated people was found.

Since chickenpox has only been notifiable since March 2013 . The data on complications have been controversial up to now, because on the one hand most harmless chickenpox cases were not recorded at all, on the other hand chickenpox complications in older children, adolescents or adolescents may not have been treated or recorded as such. Up until 2013, chickenpox was only notifiable as long as children were attending a community facility (kindergarten, school).

Chickenpox in pregnancy

Since only around 3–4% of all women of childbearing age do not have antibodies against varicella zoster virus and are therefore susceptible to the disease, chickenpox occurs rarely during pregnancy with around 1–7 cases per 10,000 pregnancies. Because of the potentially serious consequences for both the pregnant woman and the unborn child, they deserve special consideration. On the other hand, shingles does not represent an increased risk for mother or child during pregnancy, because on the one hand the viruses do not spread through the blood and on the other hand the mother produces antibodies against the pathogens that are transmitted to the unborn child and protect it from infection.

Chickenpox in pregnant women

Successful pregnancy requires changes in the immune system to tolerate the fetus that is genetically different from the mother . Although little is known about these adaptation processes of the immune system , it is a recognized fact that during pregnancy there is both an increased susceptibility to infections and more difficult courses of infectious diseases can be observed. Chickenpox is about ten times more likely to cause pneumonia as a complication in pregnant women than in non-pregnant women. At the same time, the mortality from such varicella pneumonia increases about three times from about 11 to 35%.

Fetal varicella syndrome

The chickenpox pathogen can be transmitted from the sick mother to the child via the placenta ( diaplacental ) during the entire pregnancy. The type of damage depends on the point in time and ranges from the symptom-free infection to the miscarriage . Since transmission is to be expected in only about a quarter of chickenpox cases during pregnancy and only a fraction of these are affected by fetal varicella syndrome, embryo or fetopathy is only about 1–2% of all Chickenpox found in pregnancy. A review lists a total of 112 cases since it was first described in 1947. As the most common symptom, skin defects that can be assigned to a so-called dermatome are observed in around three quarters of the cases, followed by damage to the nervous system ( tissue atrophy of the brain or spinal cord , paralysis, seizures and others) in almost two thirds of the children affected. About every second newborn also has eye diseases or malformations of the skeletal system. Damage to internal organs or muscles occurs comparatively less often. 25–30% of children die. Almost 80% of all fetal varicella syndromes occurred after maternal illness between the ninth and twentieth week of pregnancy, with a fundamental risk of this complication already from the fifth and up to the 24th week of pregnancy.

Congenital varicella

A chickenpox disease in the newborn must be differentiated from the fetal varicella syndrome, which was transmitted via the placenta shortly before delivery in the womb and which leads to the disease after birth up to the twelfth day of life. At risk are children whose mothers clearly develop chickenpox five days before or two days after delivery. Outside of this period, the mother has already produced so many protective antibodies and given them to the newborn that it does not become so seriously ill. Corresponding to the risky period of maternal infection, those newborns who have the rash between the sixth and eleventh days of life have a particularly high risk of a severe course of their chickenpox disease. In this group, the mortality without antiviral therapy is almost a quarter.

Shingles as a secondary disease

Shingles (herpes zoster)

About 20% of people who have been infected with the chickenpox virus will develop shingles ( herpes zoster ) at least once in their further life . The cause is the varicella zoster viruses remaining in the body after the disease, which migrate along sensitive nerve fibers into the spinal ganglia and remain latent there. With a weakened immune system, also caused by stress, these viruses can now be reactivated and cause shingles in the area of ​​the affected nerves.

Patients with shingles can transmit chickenpox to the unprotected.

therapy

Treatment of chickenpox is usually limited to symptomatic measures. This includes relieving existing itching by applying cool, damp compresses or applying astringent emulsions. The child's fingernails can be cut to minimize the risk of developing a bacterial superinfection. An existing fever can be treated with paracetamol or ibuprofen . Acetylsalicylic acid is contraindicated in children because it may cause Reye's syndrome .

Acyclovir or vidarabine can help minimize symptoms in children older than two years as antiviral causative therapy, provided they are taken within 24 hours. One of these medications is always indicated if there is an existing immune deficiency . Studies have shown that brivudine is 100 times more effective than acyclovir and can therefore be given in smaller doses and only once a day.

prevention

Exposure prophylaxis

In the home environment, no special measures are required for patients or contact persons. Only people at risk should avoid contact with the sick. In hospitals, on the other hand, patients with chickenpox must be strictly isolated. In addition, varicella sufferers are not allowed to carry out activities in communal facilities (Section 34 (1) Infection Protection Act ) where they come into contact with the people they care for.

Post exposure prophylaxis

After infection with varicella a preventive treatment (may be post-exposure prophylaxis ) (so-called varicella zoster with an antibody preparation containing a particularly high proportion of specific antibodies to varicella zoster virus immunoglobulin ) prevent the onset of the disease when it administered within the first 96 hours. This is recommended for pregnant women without vaccination and without a history of chickenpox, patients with weakened immune systems with no or unknown varicella immunity, and newborns whose mothers develop chickenpox five days before to two days after delivery.

vaccination

A vaccination is available and has been one of the vaccinations recommended by the STIKO ( Standing Vaccination Commission ) since July 2004 .

vaccine

The vaccine consists of weakened varicella zoster viruses that multiply in the vaccinated person. The vaccination can be given from the age of nine or twelve months (depending on the vaccine manufacturer). Children before their 13th birthday are given an injection . For children from the age of 13, adults and infants who have received a first vaccination before the age of twelve months, a second injection is required at least six weeks apart. If the immune system is normal , immunity will be acquired about three to five weeks after the last injection. A double vaccination increases the vaccination protection from 72 to over 90%.

A quadruple vaccine against measles , mumps , rubella and varicella ( MMRV ) has been approved in Germany and generally available since August 2006 . The preparation is approved for children between 9 months and 12 years and must be vaccinated twice. Since September 2011, the STIKO at the RKI has been recommending not to use the quadruple vaccine for the first vaccination against varicella, but to separate the vaccination against chickenpox from that against measles, mumps, rubella (MMR), because comparative studies have shown that the first Vaccination with MMRV combination vaccine 5–12 days after vaccination, increased fever occurred compared to the simultaneous vaccination of MMR and chickenpox vaccine at two different vaccination sites. The second vaccination against MMRV, on the other hand, can be done with a combination vaccine; there were no differences in the development of fever.

Indications for vaccination

The vaccination is recommended in Germany for children aged 11 to 14 months, or at least four weeks after the MMR vaccination . People who have not yet had chickenpox should be vaccinated between the ages of 9 and 17. For susceptible people, there is also a vaccination recommendation for women who want to have children, patients with severe neurodermatitis, patients with leukemia , patients before planned immunosuppressive therapy or organ transplantation , people who have contact with the above-mentioned patients, medical staff ( especially in paediatrics, oncology , gynecology / obstetrics and intensive care medicine ) and new employees in community facilities for preschoolers.

In Austria, a varicella vaccination has been recommended since 2005 for all unvaccinated 9 to 17-year-olds without a history of chickenpox.

In Switzerland, the varicella-zoster vaccination is recommended for all 11 to 15 year olds without a history of chickenpox. Re-vaccination is recommended for all young adults under 40, especially women who want to have children, if they have not yet had chickenpox.

Contraindications to vaccination

Anyone suffering from an acute illness requiring treatment with a fever (over 38.5 ° C) should not be vaccinated. In general, people with a weakened immune system are not vaccinated against chickenpox, although exceptions may and may be necessary.

Vaccination is usually not given during pregnancy as the vaccine virus could be transmitted to the unborn child. For the same reason, pregnancy should be avoided for at least three months after vaccination. If, however, a pregnant woman should have been vaccinated by chance, for example because the pregnancy has not yet been determined, there is no reason to terminate the pregnancy , because in such cases no damage to the unborn child has yet been proven.

history

For a long time, chickenpox was viewed as a special form of smallpox . For the first time in the 16th century they were distinguished from these by various authors under the term Cristalli or Verole volante (flying leaves) (cf. French petite vérole volante ). The expression chickenpox is attributed to Daniel Sennert in 1632 , among others . It was not until the English doctor William Heberden that chicken pox was clearly differentiated from smallpox, although this remained a point of contention among scholars until the 19th century. From the second half of the 19th century onwards, Eduard Heinrich Henoch and Antoine Marfan presented the dangers of the disease in more detail. In 1894 , the Hamburg dermatologist Paul Gerson Unna described the fine-tissue ( histological ) changes in the smallpox-like elements exactly. In the first half of the 20th century, the connection between chickenpox and shingles was gradually recognized and finally demonstrated in human experiments in 1925 . From 1952 onwards, serum was used by convalescents to treat severe disease, even before it was recognized in 1956 that people with weak immune systems are particularly at risk from the disease. In 1947, electron microscopic evidence of the causative virus was successful .

Reporting requirement

In Germany, chickenpox is a reportable disease according to Section 6 (1) of the Infection Protection Act . You are required to report by name in the event of suspicion, illness or death. Since March 23, 2013, chickenpox (formerly: "varicella") is notifiable under German law.

Web links

Commons : Chickenpox  - album with pictures, videos and audio files
Wiktionary: Chickenpox  - explanations of meanings, word origins, synonyms, translations

Individual evidence

  1. ^ Albrecht N. Rauch: disease names in German. A dialectological and etymological study of the names for diphtheria, Febris scarlatina, Morbilli, parotitis epidemica and varicellae. Stuttgart 1995 (= Journal for Dialectology and Linguistics , Supplement 84).
  2. ↑ a b c d Justification of the STIKO for a general varicella vaccination (PDF)
  3. ↑ a b ImpfDialog 3/2006: Questions and answers about vaccination ( Memento from December 6, 2008 in the Internet Archive )
  4. ^ A b German Society for Pediatric Infectious Diseases : Handbook Infections in Children and Adolescents. 2nd edition, Futuramed Verlag Munich 1997
  5. ↑ a b c d e f Varicella (chickenpox), herpes zoster (shingles) : RKI leaflet
  6. ^ A. Svahn et al .: Changes in seroprevalence to four herpesviruses over 30 years in Swedish children aged 9-12 years . J. Clin. Virol. (2006) 37 (2): pp. 118-123, PMID 16971177
  7. ^ J. Gallagher et al .: Susceptibility to varicella zoster virus infection in health care workers . Occup. Med. (Lond). (1996) 46 (4): pp. 289-292, PMID 8854707
    S. J. Knowles et al .: Susceptibility to infectious rash illness in pregnant women from diverse geographical regions . Commun. Dis. Public health. (2004) 7 (4): pp. 344-348, PMID 15779804
  8. ↑ JW Gnann et al .: Varicella-zoster virus: atypical presentations and unusual complications . J. Infect. Dis. (2002) 15; 186 (Suppl 1): S. S91-S98 (Review), PMID 12353193
  9. ↑ Ulrich Heininger, Daniel Desgrandchamps, Urs B. Schaad: Seroprevalence of Varicella-Zoster virus IgG antibodies in Swiss children during the first 16 months of age . In: Vaccine . tape 24 , no. 16 , 2006, pp. 3258-3260 , doi : 10.1016 / j.vaccine.2006.01.026 .
  10. ↑ C.-C. Ku et al .: Varicella-Zoster virus pathogenesis and immunobiology: new concepts emerging from investigations with the SCIDhu mouse model. In: J Virol. 2005 Mar; 79 (5): 2651-2658, PMID 15708984 full text (English)
  11. ^ R. Askalan et al .: Chickenpox and stroke in childhood: a study of frequency and causation. Stroke. 2001; 32 (6): 1257-62, PMID 11387484
  12. ↑ a b Bonhoeffer J., Heininger, U .: Varicella vaccination in Switzerland. In: Pediatrica 2008; 19 (3): 45-47 swiss-paediatrics.org ( Memento of the original from September 24, 2015 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. (PDF) @1@ 2Template: Webachiv / IABot / www.swiss-paediatrics.org
  13. ↑ a b Act Implementing the International Health Regulations (2005) and Amending Other Acts. (PDF) Article 3: Amendment of the Infection Protection Act. In: BGBl. I p. 566. March 28, 2013, accessed on March 14, 2020 .
  14. ↑ a b c A. Sauerbrei, P. Wutzler: Fetal varicella syndrome . In: Monthly Pediatrics . tape 151 , no. 2 , 2003, p. 209-213 , doi : 10.1007 / s00112-002-0478-z .
  15. ↑ a b A. Sauerbrei, P. Wutzler: Neonatal Varicella . In: Journal of Perinatology 2001; 21: 545-549, PMID 11774017 .
  16. ↑ DJ Jamieson et al .: Emerging infections and pregnancy . In: Emerg Infect Dis . 2006; 12 (11): 1638-1643, PMID 17283611 , cdc.gov (PDF; Engl.)
  17. ↑ Guidelines of the German Dermatological Society - Working Group on Dermatological Infectiology: Zoster and Zoster Pain, Epidemiology ( Memento from March 23, 2010 in the Internet Archive ).
  18. ↑ For combined vaccination against measles, mumps, rubella and varicella (MMRV) . In: Robert Koch Institute (Ed.): Epidemiologisches Bulletin . No. 38 , September 26, 2011, p. 352-353 ( PDF ).
  19. ^ Federal Ministry for Health, Families and Youth of Austria ( Memento of November 28, 2008 in the Internet Archive ) (PDF)
  20. ^ FPO Nagler and Geoffrey Rake: The Use of the Electron Microscope in Diagnosis of Variola, Vaccinia, and Varicella , J Bacteriol. 1948 January; 55 (1): 45-51. PMC 518406 (free full text)
  21. ↑ Max Micoud: The Infectious Diseases: Clinical Observation. Illustrated history of medicine , p. 4419 (see GdMed Vol. 4, p. 2200) 1986
This article was added to the list of excellent articles on September 11, 2008 in this version .