Shingles | |
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Other names | Herpes zoster |
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Herpes zoster blisters on the neck and shoulder | |
Specialty | Dermatology |
Symptoms | Painful rash |
Complications | Meningitis, facial nerve palsy, keratitis, postherpetic neuralgia [1] |
Duration | 2–4 weeks [2] |
Causes | Varicella zoster virus (VZV) [1] |
Risk factors | Old age, poor immune function, having had chickenpox before 18 months of age [1] |
Diagnostic method | Based on symptoms [3] |
Differential diagnosis | Herpes simplex, chest pain, insect bites, cutaneous leishmaniasis [4] |
Prevention | Shingles vaccine [1] |
Medication | Aciclovir (if given early), pain medication [3] |
Frequency | 33% (at some point) [1] |
Deaths | 6,400 (with chickenpox) [5] |
Shingles, also known as herpes zoster, is a viral disease characterized by a painful skin rash with blisters in a localized area. [2] [6] Typically the rash occurs in a single, wide mark either on the left or right side of the body or face. [1] Two to four days before the rash occurs there may be tingling or local pain in the area. [1] [7] Other common symptoms are fever, headache, and tiredness. [1] [8] The rash usually heals within two to four weeks; [2] however, some people develop ongoing nerve pain which can last for months or years, a condition called postherpetic neuralgia (PHN). [1] In those with poor immune function the rash may occur widely. [1] If the rash involves the eye, vision loss may occur. [2] [9]
Shingles is caused by the varicella zoster virus (VZV) that also causes chickenpox. In the case of chickenpox, also called varicella, the initial infection with the virus typically occurs during childhood or adolescence. [1] Once the chickenpox has resolved, the virus can remain dormant (inactive) in human nerve cells (dorsal root ganglia or cranial nerves) [10] for years or decades, after which it may reactivate and travel along nerve bodies to nerve endings in the skin, producing blisters. [1] [7] During an outbreak of shingles, exposure to the varicella virus found in shingles blisters can cause chickenpox in someone who has not yet had chickenpox, although that person will not suffer from shingles, at least on the first infection. [11] How the virus remains dormant in the body or subsequently re-activates is not well understood. [1] [12]
The disease has been recognized since ancient times. [1] Risk factors for reactivation of the dormant virus include old age, poor immune function, and having contracted chickenpox before 18 months of age. [1] Diagnosis is typically based on the signs and symptoms presented. [3] Varicella zoster virus is not the same as herpes simplex virus , although they belong to the same family of herpesviruses. [13]
Shingles vaccines reduce the risk of shingles by 50 to 90%, depending on the vaccine used. [1] [14] Vaccination also decreases rates of postherpetic neuralgia, and, if shingles occurs, its severity. [1] If shingles develops, antiviral medications such as aciclovir can reduce the severity and duration of disease if started within 72 hours of the appearance of the rash. [3] Evidence does not show a significant effect of antivirals or steroids on rates of postherpetic neuralgia. [15] [16] Paracetamol, NSAIDs, or opioids may be used to help with acute pain. [3]
It is estimated that about a third of people develop shingles at some point in their lives. [1] While shingles is more common among older people, children may also get the disease. [13] According to the US National Institutes of Health, the number of new cases per year ranges from 1.2 to 3.4 per 1,000 person-years among healthy individuals to 3.9 to 11.8 per 1,000 person-years among those older than 65 years of age. [8] [17] About half of those living to age 85 will have at least one attack, and fewer than 5% will have more than one attack. [1] [18] Although symptoms can be severe, risk of death is very low: 0.28 to 0.69 deaths per million. [10]
The earliest symptoms of shingles, which include headache, fever, and malaise, are nonspecific, and may result in an incorrect diagnosis. [8] [19] These symptoms are commonly followed by sensations of burning pain, itching, hyperesthesia (oversensitivity), or paresthesia ("pins and needles": tingling, pricking, or numbness). [20] Pain can be mild to severe in the affected dermatome, with sensations that are often described as stinging, tingling, aching, numbing or throbbing, and can be interspersed with quick stabs of agonizing pain. [21]
Shingles in children is often painless, but people are more likely to get shingles as they age, and the disease tends to be more severe. [22]
In most cases, after one to two days—but sometimes as long as three weeks—the initial phase is followed by the appearance of the characteristic skin rash. The pain and rash most commonly occur on the torso but can appear on the face, eyes, or other parts of the body. At first, the rash appears similar to the first appearance of hives; however, unlike hives, shingles causes skin changes limited to a dermatome, normally resulting in a stripe or belt-like pattern that is limited to one side of the body and does not cross the midline. [20] Zoster sine herpete ("zoster without herpes") describes a person who has all of the symptoms of shingles except this characteristic rash. [23]
Later the rash becomes vesicular, forming small blisters filled with a serous exudate, as the fever and general malaise continue. The painful vesicles eventually become cloudy or darkened as they fill with blood, and crust over within seven to ten days; usually the crusts fall off and the skin heals, but sometimes, after severe blistering, scarring and discolored skin remain. [20] The blister fluid contains varicella zoster virus, which can be transmitted through contact or inhalation of fluid droplets until the lesions crust over, which may take up to four weeks. [24]
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Shingles may have additional symptoms, depending on the dermatome involved. The trigeminal nerve is the most commonly involved nerve, [25] of which the ophthalmic division is the most commonly involved branch. [26] When the virus is reactivated in this nerve branch it is termed zoster ophthalmicus . The skin of the forehead, upper eyelid and orbit of the eye may be involved. Zoster ophthalmicus occurs in approximately 10% to 25% of cases. In some people, symptoms may include conjunctivitis, keratitis, uveitis, and optic nerve palsies that can sometimes cause chronic ocular inflammation, loss of vision, and debilitating pain. [27]
Shingles oticus, also known as Ramsay Hunt syndrome type II, involves the ear. It is thought to result from the virus spreading from the facial nerve to the vestibulocochlear nerve. Symptoms include hearing loss and vertigo (rotational dizziness). [28]
Shingles may occur in the mouth if the maxillary or mandibular division of the trigeminal nerve is affected, [29] in which the rash may appear on the mucous membrane of the upper jaw (usually the palate, sometimes the gums of the upper teeth) or the lower jaw (tongue or gums of the lower teeth) respectively. [30] Oral involvement may occur alone or in combination with a rash on the skin over the cutaneous distribution of the same trigeminal branch. [29] As with shingles of the skin, the lesions tend to only involve one side, distinguishing it from other oral blistering conditions. [30] In the mouth, shingles appears initially as 1–4 mm opaque blisters (vesicles), [29] which break down quickly to leave ulcers that heal within 10–14 days. [30] The prodromal pain (before the rash) may be confused with toothache. [29] Sometimes this leads to unnecessary dental treatment. [30] Post-herpetic neuralgia uncommonly is associated with shingles in the mouth. [30] Unusual complications may occur with intra-oral shingles that are not seen elsewhere. Due to the close relationship of blood vessels to nerves, the virus can spread to involve the blood vessels and compromise the blood supply, sometimes causing ischemic necrosis. [29] In rare cases, oral involvement causes complications such as osteonecrosis, tooth loss, periodontitis (gum disease), pulp calcification, pulp necrosis, periapical lesions and tooth developmental anomalies. [25]
In those with deficits in immune function, disseminated shingles may occur (wide rash). [1] It is defined as more than 20 skin lesions appearing outside either the primarily affected dermatome or dermatomes directly adjacent to it. Besides the skin, other organs, such as the liver or brain, may also be affected (causing hepatitis or encephalitis, [31] [32] respectively), making the condition potentially lethal. [33] : 380
The causative agent for shingles is the varicella zoster virus (VZV)—a double-stranded DNA virus related to the herpes simplex virus. Most individuals are infected with this virus as children which causes an episode of chickenpox. The immune system eventually eliminates the virus from most locations, but it remains dormant (or latent) in the ganglia adjacent to the spinal cord (called the dorsal root ganglion) or the trigeminal ganglion in the base of the skull. [35]
Shingles occurs only in people who have been previously infected with VZV; although it can occur at any age, approximately half of the cases in the United States occur in those aged 50 years or older. [36] Shingles can recur. [37] In contrast to the frequent recurrence of herpes simplex symptoms, repeated attacks of shingles are unusual. [38] It is extremely rare for a person to have more than three recurrences. [35]
The disease results from virus particles in a single sensory ganglion switching from their latent phase to their active phase. [39] Due to difficulties in studying VZV reactivation directly in humans (leading to reliance on small-animal models), its latency is less well understood than that of the herpes simplex virus. [38] Virus-specific proteins continue to be made by the infected cells during the latent period, so true latency, as opposed to chronic, low-level, active infection, has not been proven to occur in VZV infections. [40] [41] Although VZV has been detected in autopsies of nervous tissue, [42] there are no methods to find dormant virus in the ganglia of living people.
Unless the immune system is compromised, it suppresses reactivation of the virus and prevents shingles outbreaks. Why this suppression sometimes fails is poorly understood, [43] but shingles is more likely to occur in people whose immune systems are impaired due to aging, immunosuppressive therapy, psychological stress, or other factors. [44] [45] Upon reactivation, the virus replicates in neuronal cell bodies, and virions are shed from the cells and carried down the axons to the area of skin innervated by that ganglion. In the skin, the virus causes local inflammation and blistering. The short- and long-term pain caused by shingles outbreaks originates from inflammation of affected nerves due to the widespread growth of the virus in those areas. [46]
As with chickenpox and other forms of alpha-herpesvirus infection, direct contact with an active rash can spread the virus to a person who lacks immunity to it. This newly infected individual may then develop chickenpox, but will not immediately develop shingles. [20]
The complete sequence of the viral genome was published in 1986. [47]
If the rash has appeared, identifying this disease (making a differential diagnosis) requires only a visual examination, since very few diseases produce a rash in a dermatomal pattern (sometimes called by doctors on TV "a dermatonal map").[ citation needed ] However, herpes simplex virus (HSV) can occasionally produce a rash in such a pattern (zosteriform herpes simplex). [48] [49]
When the rash is absent (early or late in the disease, or in the case of zoster sine herpete), shingles can be difficult to diagnose. [50] Apart from the rash, most symptoms can occur also in other conditions.
Laboratory tests are available to diagnose shingles. The most popular test detects VZV-specific IgM antibody in blood; this appears only during chickenpox or shingles and not while the virus is dormant. [51] In larger laboratories, lymph collected from a blister is tested by polymerase chain reaction (PCR) for VZV DNA, or examined with an electron microscope for virus particles. [52] Molecular biology tests based on in vitro nucleic acid amplification (PCR tests) are currently considered the most reliable. Nested PCR test has high sensitivity, but is susceptible to contamination leading to false positive results. The latest real-time PCR tests are rapid, easy to perform, and as sensitive as nested PCR, and have a lower risk of contamination. They also have more sensitivity than viral cultures. [53]
Shingles can be confused with herpes simplex, dermatitis herpetiformis and impetigo, and skin reactions caused by contact dermatitis, candidiasis, certain drugs and insect bites. [54]
Shingles risk can be reduced in children by the chickenpox vaccine if the vaccine is administered before the individual gets chickenpox. [55] If primary infection has already occurred, there are shingles vaccines that reduce the risk of developing shingles or developing severe shingles if the disease occurs. [1] [14] They include a live attenuated virus vaccine, Zostavax, and an adjuvanted subunit vaccine, Shingrix. [37] [56] [57]
A review by Cochrane concluded that Zostavax was useful for preventing shingles for at least three years. [7] This equates to about 50% relative risk reduction. The vaccine reduced rates of persistent, severe pain after shingles by 66% in people who contracted shingles despite vaccination. [58] Vaccine efficacy was maintained through four years of follow-up. [58] It has been recommended that people with primary or acquired immunodeficiency should not receive the live vaccine. [58]
Two doses of Shingrix are recommended, which provide about 90% protection at 3.5 years. [37] [57] As of 2016, it had been studied only in people with an intact immune system. [14] It appears to also be effective in the very old. [14]
In the UK, shingles vaccination is offered by the National Health Service (NHS) to all people in their 70s. As of 2021 [update] Zostavax is the usual vaccine, but Shingrix vaccine is recommended if Zostavax is unsuitable, for example for those with immune system issues. Vaccination is not available to people over 80 as "it seems to be less effective in this age group". [59] [60] By August 2017, just under half of eligible 70–78 year olds had been vaccinated. [61] About 3% of those eligible by age have conditions that suppress their immune system, and should not receive Zostavax. [62] There had been 1,104 adverse reaction reports by April 2018. [62] In the US, it is recommended that healthy adults 50 years and older receive two doses of Shingrix, two to six months apart. [37] [63]
The aims of treatment are to limit the severity and duration of pain, shorten the duration of a shingles episode, and reduce complications. Symptomatic treatment is often needed for the complication of postherpetic neuralgia. [64] However, a study on untreated shingles shows that, once the rash has cleared, postherpetic neuralgia is very rare in people under 50 and wears off in time; in older people, the pain wore off more slowly, but even in people over 70, 85% were free from pain a year after their shingles outbreak. [65]
People with mild to moderate pain can be treated with over-the-counter pain medications. Topical lotions containing calamine can be used on the rash or blisters and may be soothing. Occasionally, severe pain may require an opioid medication, such as morphine. Once the lesions have crusted over, capsaicin cream (Zostrix) can be used. Topical lidocaine and nerve blocks may also reduce pain. [66] Administering gabapentin along with antivirals may offer relief of postherpetic neuralgia. [64]
Antiviral drugs may reduce the severity and duration of shingles; [67] however, they do not prevent postherpetic neuralgia. [68] Of these drugs, aciclovir has been the standard treatment, but the newer drugs valaciclovir and famciclovir demonstrate similar or superior efficacy and good safety and tolerability. [64] The drugs are used both for prevention (for example in people with HIV/AIDS) and as therapy during the acute phase. Complications in immunocompromised individuals with shingles may be reduced with intravenous aciclovir. In people who are at a high risk for repeated attacks of shingles, five daily oral doses of aciclovir are usually effective. [28]
Corticosteroids do not appear to decrease the risk of long-term pain. [16] Side effects however appear to be minimal. Their use in Ramsay Hunt syndrome had not been properly studied as of 2008. [69]
Treatment for zoster ophthalmicus is similar to standard treatment for shingles at other sites.[ medical citation needed ] A trial comparing aciclovir with its prodrug, valaciclovir, demonstrated similar efficacies in treating this form of the disease. [70]
The rash and pain usually subside within three to five weeks, but about one in five people develop a painful condition called postherpetic neuralgia, which is often difficult to manage. In some people, shingles can reactivate presenting as zoster sine herpete: pain radiating along the path of a single spinal nerve (a dermatomal distribution), but without an accompanying rash. This condition may involve complications that affect several levels of the nervous system and cause many cranial neuropathies, polyneuritis, myelitis, or aseptic meningitis. Other serious effects that may occur in some cases include partial facial paralysis (usually temporary), ear damage, or encephalitis. [28] Although initial infections with VZV during pregnancy, causing chickenpox, may lead to infection of the fetus and complications in the newborn, chronic infection or reactivation in shingles are not associated with fetal infection. [71] [72]
There is a slightly increased risk of developing cancer after a shingles episode. However, the mechanism is unclear and mortality from cancer did not appear to increase as a direct result of the presence of the virus. [73] Instead, the increased risk may result from the immune suppression that allows the reactivation of the virus. [74]
Although shingles typically resolves within 3–5 weeks, certain complications may arise:
Varicella zoster virus (VZV) has a high level of infectivity and has a worldwide prevalence. [77] Shingles is a re-activation of latent VZV infection: zoster can only occur in someone who has previously had chickenpox (varicella).
Shingles has no relationship to season and does not occur in epidemics. There is, however, a strong relationship with increasing age. [22] [44] The incidence rate of shingles ranges from 1.2 to 3.4 per 1,000 person‐years among younger healthy individuals, increasing to 3.9–11.8 per 1,000 person‐years among those older than 65 years, [8] [22] and incidence rates worldwide are similar. [8] [78] This relationship with age has been demonstrated in many countries, [8] [78] [79] [80] [81] [82] and is attributed to the fact that cellular immunity declines as people grow older.
Another important risk factor is immunosuppression. [83] [84] [85] Other risk factors include psychological stress. [21] [86] [87] According to a study in North Carolina, "black subjects were significantly less likely to develop zoster than were white subjects." [88] [89] It is unclear whether the risk is different by sex. Other potential risk factors include mechanical trauma and exposure to immunotoxins. [44] [87]
There is no strong evidence for a genetic link or a link to family history. A 2008 study showed that people with close relatives who had shingles were twice as likely to develop it themselves, [90] but a 2010 study found no such link. [87]
Adults with latent VZV infection who are exposed intermittently to children with chickenpox receive an immune boost. [22] [87] This periodic boost to the immune system helps to prevent shingles in older adults. When routine chickenpox vaccination was introduced in the United States, there was concern that, because older adults would no longer receive this natural periodic boost, there would be an increase in the incidence of shingles.
Multiple studies and surveillance data, at least when viewed superficially, demonstrate no consistent trends in incidence in the U.S. since the chickenpox vaccination program began in 1995. [91] However, upon closer inspection, the two studies that showed no increase in shingles incidence were conducted among populations where varicella vaccination was not as yet widespread in the community. [92] [93] A later study by Patel et al. concluded that since the introduction of the chickenpox vaccine, hospitalization costs for complications of shingles increased by more than $700 million annually for those over age 60. [94] Another study by Yih et al. reported that as varicella vaccine coverage in children increased, the incidence of varicella decreased, and the occurrence of shingles among adults increased by 90%. [95] The results of a further study by Yawn et al. showed a 28% increase in shingles incidence from 1996 to 2001. [96] It is likely that incidence rate will change in the future, due to the aging of the population, changes in therapy for malignant and autoimmune diseases, and changes in chickenpox vaccination rates; a wide adoption of zoster vaccination could dramatically reduce the incidence rate. [8]
In one study, it was estimated that 26% of those who contract shingles eventually present complications. Postherpetic neuralgia arises in approximately 20% of people with shingles. [97] A study of 1994 California data found hospitalization rates of 2.1 per 100,000 person-years, rising to 9.3 per 100,000 person-years for ages 60 and up. [98] An earlier Connecticut study found a higher hospitalization rate; the difference may be due to the prevalence of HIV in the earlier study, or to the introduction of antivirals in California before 1994. [99]
Shingles has a long recorded history, although historical accounts fail to distinguish the blistering caused by VZV and those caused by smallpox, [36] ergotism, and erysipelas. In the late 18th century William Heberden established a way to differentiate shingles and smallpox, [100] and in the late 19th century, shingles was differentiated from erysipelas. In 1831 Richard Bright hypothesized that the disease arose from the dorsal root ganglion, and an 1861 paper by Felix von Bärensprung confirmed this. [101]
Recognition that chickenpox and shingles were caused by the same virus came at the beginning of the 20th century. Physicians began to report that cases of shingles were often followed by chickenpox in younger people who lived with the person with shingles. The idea of an association between the two diseases gained strength when it was shown that lymph from a person with shingles could induce chickenpox in young volunteers. This was finally proved by the first isolation of the virus in cell cultures, by the Nobel laureate Thomas Huckle Weller, in 1953. [102] Some sources also attribute the first isolation of the herpes zoster virus to Evelyn Nicol. [103]
Until the 1940s the disease was considered benign, and serious complications were thought to be very rare. [104] However, by 1942, it was recognized that shingles was a more serious disease in adults than in children and that it increased in frequency with advancing age. Further studies during the 1950s on immunosuppressed individuals showed that the disease was not as benign as once thought, and the search for various therapeutic and preventive measures began. [105] By the mid-1960s, several studies identified the gradual reduction in cellular immunity in old age, observing that in a cohort of 1,000 people who lived to the age of 85, approximately 500 (i.e., 50%) would have at least one attack of shingles, and 10 (i.e., 1%) would have at least two attacks. [106]
In historical shingles studies, shingles incidence generally increased with age. However, in his 1965 paper, Hope-Simpson suggested that the "peculiar age distribution of zoster may in part reflect the frequency with which the different age groups encounter cases of varicella and because of the ensuing boost to their antibody protection have their attacks of zoster postponed". [22] Lending support to this hypothesis that contact with children with chickenpox boosts adult cell-mediated immunity to help postpone or suppress shingles, a study by Thomas et al. reported that adults in households with children had lower rates of shingles than households without children. [107] Also, the study by Terada et al. indicated that pediatricians reflected incidence rates from 1/2 to 1/8 that of the general population their age. [108]
The family name of all the herpesviruses derives from the Greek word έρπης herpēs, [109] from έρπω herpein ("to creep"), [110] [111] [112] referring to the latent, recurring infections typical of this group of viruses. Zoster comes from Greek ζωστήρ zōstēr, [113] meaning "belt" or "girdle", after the characteristic belt-like dermatomal rash. [114] The common name for the disease, shingles, derives from the Latin cingulus, a variant of Latin cingulum, [115] meaning "girdle". [116] [117]
Until the mid-1990s, infectious complications of the central nervous system (CNS) caused by VZV reactivation were regarded as rare. The presence of rash, as well as specific neurological symptoms, were required to diagnose a CNS infection caused by VZV. Since 2000, PCR testing has become more widely used, and the number of diagnosed cases of CNS infection has increased. [118]
Classic textbook descriptions state that VZV reactivation in the CNS is restricted to immunocompromised individuals and the elderly; however, studies have found that most participants are immunocompetent, and younger than 60 years old. Historically, vesicular rash was considered a characteristic finding, but studies have found that rash is only present in 45% of cases. [118] In addition, systemic inflammation is not as reliable an indicator as previously thought: the mean level of C-reactive protein and mean white blood cell count are within the normal range in participants with VZV meningitis. [119] MRI and CT scans are usually normal in cases of VZV reactivation in the CNS. CSF pleocytosis, previously thought to be a strong indicator of VZV encephalitis, was absent in half of a group of people diagnosed with VZV encephalitis by PCR. [118]
The frequency of CNS infections presented at the emergency room of a community hospital is not negligible, so a means of diagnosing cases is needed. PCR is not a foolproof method of diagnosis, but because so many other indicators have turned out not to be reliable in diagnosing VZV infections in the CNS, screening for VZV by PCR is recommended. Negative PCR does not rule out VZV involvement, but a positive PCR can be used for diagnosis, and appropriate treatment started (for example, antivirals can be prescribed rather than antibiotics). [118]
The introduction of DNA analysis techniques has shown some complications of varicella-zoster to be more common than previously thought. For example, sporadic meningoencephalitis (ME) caused by varicella-zoster was regarded as rare disease, mostly related to childhood chickenpox. However, meningoencephalitis caused by varicella-zoster is increasingly recognized as a predominant cause of ME among immunocompetent adults in non-epidemic circumstances. [120]
Diagnosis of complications of varicella-zoster, particularly in cases where the disease reactivates after years or decades of latency, is difficult. A rash (shingles) can be present or absent. Symptoms vary, and there is a significant overlap in symptoms with herpes-simplex symptoms. [120]
Although DNA analysis techniques such as polymerase chain reaction (PCR) can be used to look for DNA of herpesviruses in spinal fluid or blood, the results may be negative, even in cases where other definitive symptoms exist. [121] Notwithstanding these limitations, the use of PCR has resulted in an advance in the state of the art in our understanding of herpesviruses, including VZV, during the 1990s and 2000s. For example, in the past, clinicians believed that encephalitis was caused by herpes simplex and that people always died or developed serious long-term function problems. People were diagnosed at autopsy or by brain biopsy. Brain biopsy is not undertaken lightly: it is reserved only for serious cases that cannot be diagnosed by less invasive methods. For this reason, knowledge of these herpes virus conditions was limited to severe cases. DNA techniques have made it possible to diagnose "mild" cases, caused by VZV or HSV, in which the symptoms include fever, headache, and altered mental status. Mortality rates in treated people are decreasing. [120]
Ramsay Hunt syndrome type 2, commonly referred to simply as Ramsay Hunt syndrome (RHS) and also known as herpes zoster oticus, is inflammation of the geniculate ganglion of the facial nerve as a late consequence of varicella zoster virus (VZV). In regard to the frequency, less than 1% of varicella zoster infections involve the facial nerve and result in RHS. It is traditionally defined as a triad of ipsilateral facial paralysis, otalgia, and vesicles close to the ear and auditory canal. Due to its proximity to the vestibulocochlear nerve, the virus can spread and cause hearing loss, tinnitus, and vertigo. It is common for diagnoses to be overlooked or delayed, which can raise the likelihood of long-term consequences. It is more complicated than Bell's palsy. Therapy aims to shorten its overall length, while also providing pain relief and averting any consequences.
Varicella zoster virus (VZV), also known as human herpesvirus 3 or Human alphaherpesvirus 3 (taxonomically), is one of nine known herpes viruses that can infect humans. It causes chickenpox (varicella) commonly affecting children and young adults, and shingles in adults but rarely in children. As a late complication of VZV infection, Ramsay Hunt syndrome type 2 may develop in rare cases. VZV infections are species-specific to humans. The virus can survive in external environments for a few hours.
Keratitis is a condition in which the eye's cornea, the clear dome on the front surface of the eye, becomes inflamed. The condition is often marked by moderate to intense pain and usually involves any of the following symptoms: pain, impaired eyesight, photophobia, red eye and a 'gritty' sensation. Diagnosis of infectious keratitis is usually made clinically based on the signs and symptoms as well as eye examination, but corneal scrapings may be obtained and evaluated using microbiological culture or other testing to identify the causative pathogen.
Aciclovir, also known as acyclovir, is an antiviral medication. It is primarily used for the treatment of herpes simplex virus infections, chickenpox, and shingles. Other uses include prevention of cytomegalovirus infections following transplant and severe complications of Epstein–Barr virus infection. It can be taken by mouth, applied as a cream, or injected.
Postherpetic neuralgia (PHN) is neuropathic pain that occurs due to damage to a peripheral nerve caused by the reactivation of the varicella zoster virus. PHN is defined as pain in a dermatomal distribution that lasts for at least 90 days after an outbreak of herpes zoster. Several types of pain may occur with PHN including continuous burning pain, episodes of severe shooting or electric-like pain, and a heightened sensitivity to gentle touch which would not otherwise cause pain or to painful stimuli. Abnormal sensations and itching may also occur.
Valaciclovir, also spelled valacyclovir, is an antiviral medication used to treat outbreaks of herpes simplex or herpes zoster (shingles). It is also used to prevent cytomegalovirus following a kidney transplant in high risk cases. It is taken by mouth.
Viral pneumonia is a pneumonia caused by a virus. Pneumonia is an infection that causes inflammation in one or both of the lungs. The pulmonary alveoli fill with fluid or pus making it difficult to breathe. Pneumonia can be caused by bacteria, viruses, fungi or parasites. Viruses are the most common cause of pneumonia in children, while in adults bacteria are a more common cause.
Viral encephalitis is inflammation of the brain parenchyma, called encephalitis, by a virus. The different forms of viral encephalitis are called viral encephalitides. It is the most common type of encephalitis and often occurs with viral meningitis. Encephalitic viruses first cause infection and replicate outside of the central nervous system (CNS), most reaching the CNS through the circulatory system and a minority from nerve endings toward the CNS. Once in the brain, the virus and the host's inflammatory response disrupt neural function, leading to illness and complications, many of which frequently are neurological in nature, such as impaired motor skills and altered behavior.
Brivudine is an antiviral drug used in the treatment of herpes zoster ("shingles"). Like other antivirals, it acts by inhibiting replication of the target virus.
A zoster vaccine is a vaccine that reduces the incidence of herpes zoster (shingles), a disease caused by reactivation of the varicella zoster virus, which is also responsible for chickenpox. Shingles provokes a painful rash with blisters, and can be followed by chronic pain, as well as other complications. Older people are more often affected, as are people with weakened immune systems (immunosuppression). Both shingles and postherpetic neuralgia can be prevented by vaccination.
Varicella vaccine, also known as chickenpox vaccine, is a vaccine that protects against chickenpox. One dose of vaccine prevents 95% of moderate disease and 100% of severe disease. Two doses of vaccine are more effective than one. If given to those who are not immune within five days of exposure to chickenpox it prevents most cases of disease. Vaccinating a large portion of the population also protects those who are not vaccinated. It is given by injection just under the skin. Another vaccine, known as zoster vaccine, is used to prevent diseases caused by the same virus – the varicella zoster virus.
Mollaret's meningitis is a recurrent or chronic inflammation of the protective membranes covering the brain and spinal cord, known collectively as the meninges. Since Mollaret's meningitis is a recurrent, benign (non-cancerous), aseptic meningitis, it is also referred to as benign recurrent lymphocytic meningitis. It was named for Pierre Mollaret, the French neurologist who first described it in 1944.
Chickenpox, also known as varicella, is a highly contagious, vaccine-preventable disease caused by the initial infection with varicella zoster virus (VZV), a member of the herpesvirus family. The disease results in a characteristic skin rash that forms small, itchy blisters, which eventually scab over. It usually starts on the chest, back, and face. It then spreads to the rest of the body. The rash and other symptoms, such as fever, tiredness, and headaches, usually last five to seven days. Complications may occasionally include pneumonia, inflammation of the brain, and bacterial skin infections. The disease is usually more severe in adults than in children.
In medicine, varicella zoster virus globulin, VZV antibodies, zoster immunoglobulin (ZIG), varicella zoster immune globulin, is an immune system medication that is used mostly for immunosuppressed patients who have been or may be exposed to the varicella zoster virus (VZV).
Congenital varicella syndrome is a rare disease resulting from Varicella Zoster virus (VZV) infection during the period of gestation. Viremia during the primary infection can result in transplacental transmission of the infection to the developing fetus. An estimated 25% of fetuses get infected with varicella infection when mother has a varicella infection during the pregnancy but the risk of developing congenital varicella syndrome is around 2%, therefore majority of the outcomes are normal newborns. Patients with primary infection before 20 weeks of gestation are at a higher risk of developing the severe form of infection, affecting the eyes, limbs, skin and the central nervous system. Diagnosis requires a documented history of primary infection in the mother and serial ultrasound demonstrating features suggestive of congenital varicella syndrome. There is no definitive treatment, termination of pregnancy in fetuses with severe features is recommended. Vaccination to prevent maternal varicella infection and proper counseling to avoid contact with infected people are important for the management options to reduce the incidence of congenital varicella syndrome.
Herpes zoster ophthalmicus (HZO), also known as ophthalmic zoster, is shingles involving the eye or the surrounding area. Common signs include a rash of the forehead with swelling of the eyelid. There may also be eye pain and redness, inflammation of the conjunctiva, cornea or uvea, and sensitivity to light. Fever and tingling of the skin and allodynia near the eye may precede the rash. Complications may include visual impairment, increased pressure within the eye, chronic pain, and stroke.
Stephen E. Straus was an American physician, immunologist, virologist and science administrator. He is particularly known for his research into human herpesviruses and chronic fatigue syndrome, and for his discovery of the autoimmune lymphoproliferative syndrome genetic disorder. He headed the Laboratory of Clinical Investigation of the National Institute of Allergy and Infectious Diseases, National Institutes of Health (NIH), and served as the founding director of the NIH's National Center for Complementary and Alternative Medicine.
Preherpetic neuralgia is a form of nerve pain (neuralgia) specifically associated with a Shingles viral infection. This nerve pain often precedes visible indications of a Shingles infection and consequently can be a key early indicator of a need to begin preventative anti-viral drug therapy. Pain associated with Shingles can be extremely difficult to treat whereas the source is related to the virus attacking the nervous system itself. Pain symptoms can last months or years beyond any outward sign of viral infection and can be quite severe. The combination of extreme pain severity and longevity can contribute to chronic depression and even suicide.
Live recombinant vaccines are biological preparations that stimulate immune responses to a pathogen through the use of genetically modified live bacteria or viruses. These live pathogens are biologically engineered to express exogenous antigens in the cytoplasm of target cells, thereby triggering immune responses. This form of vaccine combines the beneficial features of attenuated and recombinant vaccines, providing the long-lasting immunity of attenuated vaccines’ with recombinant vaccines’ genetically engineered precision and safety.
Anne Gershon is an infectious disease researcher and professor of pediatrics at Columbia University. She is best known for her work on the varicella-zoster virus, the causative agent for chickenpox. In the 1970s, she ran clinical trials for the varicella vaccine which showed that the vaccine was safe for children with leukemia. She also developed the first sensitive test for chickenpox.