The prodromal symptoms in adolescents and adults are aching muscles, nausea, decreased appetite, and headache followed by a rash, oral sores, malaise, and a low-grade fever. Oral manifestations may precede the skin rash. In children, the illness may not be preceded by prodromal symptoms, and the initial sign could be a rash or oral cavity lesions. The rash begins as small red dots on the face, scalp, torso, upper arms and legs. Over the next ten to 12 hours it progresses to small bumps, blisters, and pustules; and eventually umbilication and scabs formation. Of note, the rash of chickenpox occur in crops and are typically at different stages of evolution.

At the blister stage, intense pruritus is present. Blisters may occur on the palms, soles, and genital area. Commonly, visible evidence develops in the oral cavity and tonsil areas in the form of small ulcers which can be painful and itchy; this enanthem may precede the external exanthem by one to three days. These symptoms appear ten to 21 days after exposure. Adults may have a more widespread rash and longer fever, and they are more likely to develop pneumonia, the most important complication in adults.

Because watery nasal discharge containing live virus precedes exanthems by one to two days, the infected person is contagious one to two days before recognition of the disease. In the majority of cases, the infection resolves itself within two to four weeks.

A common complication is a secondary bacterial infection that can present as cellulitis, impetigo or erysipelas.

Disseminated primary varicella is usually seen in immunocompromised individuals and carries a very high mortality. CNS complications are rare but may present as Guillain barre syndrome or encephalitis.

Primary varicella infection during pregnancy can also affect the fetus, who may present later with chickenpox. In addition, the virus also has the potential to cause the varicella congenital syndrome.

The diagnosis of varicella infection is primarily based on the signs and symptoms. Confirmation is by examination of the fluid within the vesicles, scraping of lesions that have not crusted or by blood for evidence of an acute immunologic response. Polymerase chain reaction (PCR) has the highest yield and can be utilized for non-skin samples such as bronchoalveolar lavage sample and cerebrospinal fluid. Direct fluorescent antibody testing has largely replaced the Tzanck test. The vesicular fluid can also be cultured, but the yield is low compared to PCR.  Blood tests are used to identify a response to acute infection (IgM), previous infection, and subsequent immunity (IgG). Prenatal diagnosis of fetal varicella can be performed using ultrasound, though a delay of 5 weeks following primary maternal infection is advised. A PCR (DNA) test of the amniotic fluid can be performed, though the risk of spontaneous abortion due to amniocentesis is higher than the risk of the baby developing fetal varicella. [10][11]

Treatment is symptomatic relief of symptoms. As a protective measure, those infected are usually required to stay at home while they are infectious. Keeping nails short and wearing gloves may prevent scratching and reduce the risk of secondary infections. [12][13][1]

Topical calamine lotion may relieve pruritus. Daily cleansing with warm water will help avoid secondary bacterial infection. Acetaminophen may be used to reduce fever. Avoid aspirin as it may cause Reye syndrome. People at risk of developing complications and who have had significant exposure may be given intramuscular varicella-zoster immune globulin, a preparation containing high titers of antibodies to varicella-zoster virus, to help prevent the disease.[14]

• In children, acyclovir decreases symptoms by one day if taken within 24 hours of the start of the rash, but it has no effect on complication rates, and it is not recommended for individuals with normal immune function.
• In adults, infection tends to be more severe, and treatment with antiviral drugs (acyclovir or valacyclovir) is advised if they can be started within 24 to 48 hours of rash onset. Supportive care such as increasing water intake and the use of antipyretics and antihistamines are an important part of the management. Antivirals are typically indicated in adults, including pregnant women because this group is more prone to complications. The preferred treatment is usually oral therapy, but for immunocompromised patients, intravenous antivirals are indicated.

The varicella-zoster immunoglobulin is used to manage patients who are immunocompromised. In addition, a live attenuated vaccine has been available since 1995. There is high seroconversion following the vaccine which is long lasting. Adverse effects of the vaccine are rare.

• Insect bites
• Impetigo
• Small pox
• Drug eruptions
• Dermatitis herpetiformis

In healthy children, the prognosis is excellent. However, in immunocompromised individuals, the infection has high morbidity.

• Pediatrician
• Infectious disease consultant

Chickenpox is rarely fatal. Non-immune pregnant women and those immunocompromised are at highest risk. Arterial ischemic stroke associated with childhood chickenpox is a significant risk. Varicella pneumonia is the most common cause of fatality in adults (10% to 30%), and in those requiring mechanical ventilation, this may reach 50%.

In pregnant women, antibodies produced as a result of immunization or previous infection are transferred via the placenta to the fetus. Varicella infection in pregnant women could spread via the placenta and infect the fetus. If infection occurs during the first 28 weeks of pregnancy, congenital varicella syndrome may develop. Effects on the fetus can include underdeveloped toes and fingers, structural eye damage, neurological disorder, and anal and bladder malformation.

If maternal infection occurs seven days before delivery and up to eight days following birth, the baby may develop neonatal varicella with presentation ranging from mild rash to disseminated infection. Newborns who develop symptoms are at a high risk of pneumonia and other serious complications.

Maternal herpes zoster, on the other hand, constitutes little risk of neonatal complications or congenital varicella syndrome probably because of established circulating maternal antibodies.

Chickenpox is usually acquired after inhalation of aerosolized droplets from an infected individual. The majority of cases occurring in children less than 10. The key to lowering the morbidity of chickenpox is via education. Besides the primary caregiver, the nurse practitioner and pharmacist play a vital role in patient education. The parents of infected children should be told to trim the child's fingernails to avoid or minimize skin damage and the associated bacterial infections. Further, parents should be told not to give aspirin to young children to control fever, because of the risk of developing Reye syndrome. Finally, the parents should be told to apply cold compresses and keep the skin moisturized to prevent the itching and dryness.[15][16][17] All clinicians should urge parents to get their children vaccinated because this can prevent the morbidity associated with the infection. The vaccine is safe and very effective. Children who are immunocompromised should be referred to an infectious disease specialist for further management. (Level V) Clinicians should also educate pregnant women who are seronegative for chickenpox to avoid contacts with patients with an active infection. All pregnant women who develop chickenpox must be managed by a team of specialists who can make a decision regarding treatment.

Outcomes

For most children who develop chickenpox, the outcome is excellent. However, in immunocompromised individuals, there is increased morbidity and mortality. [18][19][20](Level V)