Varicella exposure in a neonatal medical centre: successful prophylaxis with oral acyclovir

Post-exposure prophylaxis to prevent varicella in immunocompromised children

Background

Varicella-zoster virus (VZV) infection can cause life-threatening events in immunocompromised patients. Post-exposure prophylaxis (PEP) is required to prevent secondary VZV infection. Limited evidence is available for the use of acyclovir (ACV)/valacyclovir (VCV) as PEP.

Methods

Herein, we retrospectively analyzed immunocompromised paediatric patients with significant exposure to VZV. Patients administered PEP were categorized into four groups: 1) ACV/VCV group; 2) intravenous immunoglobulin (IVIG) group; 3) ACV/VCV/IVIG group; 4) vaccine group.

Results

Among 69 exposure events, 107 patients were administered PEP (91, ACV/VCV; 16, ACV/VCV/IVIG) and 10 patients did not receive PEP (non-PEP group). The index case was diagnosed based on clinical symptoms in 55 cases (79.7%). Fourteen cases (20.3%) were confirmed using direct virological diagnostic procedures. In the PEP group, only 2 patients (2.2%) developed secondary VZV infections. Additionally, 2 patients in the non-PEP group (20.0%) developed secondary VZV infection. The incidence of secondary VZV infection was significantly lower in the PEP group than in the non-PEP group (P=0.036). Among patients administered PEP, no antiviral drug-induced side effects were detected.

Conclusions

Antiviral agents administered as PEP are effective and safe for preventing VZV infections in immunocompromised patients. Rapid virological diagnosis of index cases might allow efficient administration of PEP after significant exposure to VZV infection.

Case Report: Neonatal Varicella Acquired From Maternal Zoster

The incidence of neonatal varicella has decreased dramatically since the introduction of the varicella vaccination. Although the varicella zoster virus is often associated with a mild infection, it may cause severe morbidity and mortality, particularly in the neonatal period and immunocompromised hosts. We report a case of neonatal varicella acquired from maternal zoster in a mother on biological immunosuppressive therapy. Following the diagnosis, the baby improved on antiviral therapy without any neurological sequelae. This case highlights the limited published data on neonatal varicella following herpes zoster reactivation to inform practice. This includes the role of varicella zoster immunoglobulin in neonates exposed to maternal zoster, the degree of trans-placental immunity and optimum antiviral dosing and duration.

Varicella infection in a neonate with subsequent staphylococcal scalded skin syndrome and fatal shock

A male term neonate, at day 23 of life, presented with vesicular lesions over the trunk, which spread to allover the body on the next day. Five days later, he started developing blistering of the skin over the trunk and extremities, which subsequently ruptured, leaving erythematous, tender raw areas with peeling of the skin. The mother had vesicular eruptions, which started on the second day of delivery and progressed over the next 3 days. Subsequently, similar eruptions were noticed in two of the siblings before affecting the neonate. On the basis of the exposure history and clinical picture, a diagnosis was made of varicella infection with staphylococcal scalded skin syndrome (SSSS). The blood culture and the wound surface culture grew Staphylococcus aureus. Treatment included intravenous fluid, antibiotics, acyclovir and wound care. However, after 72 h of hospitalisation, the neonate first developed shock, refractory to fluid boluses, vasopressors and catecholamine along with other supports; and he then succumbed. In all neonates, staphylococcal infection with varicella can be fatal due to SSSS, the toxic shock syndrome or septicaemia.

Management and outcome of a varicella exposure in a neonatal intensive care unit: lessons for the vaccine era

BACKGROUND

Varicella exposure in health care settings poses a threat to susceptible, immunocompromised hosts. We describe the management and outcome of a varicella exposure in a neonatal intensive care unit.

METHODS

We reviewed the history of the index case, determination of the exposed cohort, medical management of exposed neonates, and assignment of health care workers based on exposure and immune status. We present the results of serologic testing of health care workers related to their history of varicella disease.

RESULTS

Of 427 health care workers assessed at the time of the exposure, 13.1% were seronegative for varicella. Among 180 employees recorded as having a previous history of varicella, 9 were seronegative. A total of 34 infants received prophylaxis with intravenous immune globulin; acyclovir prophylaxis was added for those born at <28 weeks gestational age. The exposed cohort was isolated. No secondary cases of varicella occurred among patients or health care workers.

CONCLUSION

Nosocomial varicella exposures require rapid assessment and response, which can be guided by a checklist of actions. Varicella immunity in health care workers cannot be assumed even among those born before 1980; institutional policies should adhere to the 2007 Centers for Disease Control and Prevention's definition of immunity to varicella for health care workers.