#6: Varicella Outbreak Investigation in a Cancer Hospital

Abstract Background Primary varicella infection is usually self-limited in immunocompetent hosts, whereas it can be quite severe in immunocompromised hosts. Atypical presentations of varicella in immunocompromised hosts can be diagnostically challenging, without laboratory testing. Varicella is an occupational hazard for susceptible healthcare providers (HCP). It assumes importance in infection prevention and control, due to the possibility of spread to other susceptible coworkers and patients. Methods This outbreak investigation report is from a 300-bed cancer care hospital in South India. A 62-year-old male patient with lymphoplasmacytic non-Hodgkin’s lymphoma was admitted on October 1 with features of bronchopneumonia and extensive skin lesions, 2 months after his last chemotherapy cycle. The patient was received in the emergency department (ED) and later shifted to the intensive care unit (ICU) due to worsening clinical condition. The clinical picture was more in favor of Stevens–Johnson syndrome, but oral acyclovir therapy was given considering a differential diagnosis of varicella. His condition deteriorated further requiring ventilator support and on the 19th day of admission, the patient succumbed to his illness and passed away. From October 14 to 19, eight HCP presented with vesicular eruptions and fever, clinically diagnosed as having varicella. This aroused the suspicion of an outbreak. An emergency outbreak control group meeting was convened to assess and address the situation. Results All outbreak cases were confirmed as varicella, clinically. Contacts, including patients assigned to HCP involved in the outbreak were traced, and their varicella immune status was assessed. Nonimmune contacts were given oral acyclovir prophylaxis as per CDC recommendations. Other HCP in the hospital were offered first dose of varicella vaccine based on their varicella immune status. With these infection prevention and control measures in place, no additional cases were identified. Being a hospital in low- to middle-income country, it was not routine practice to vaccinate susceptible HCP, after screening of varicella immune status at the time of recruitment. In the wake of the outbreak, assessment of immunity against varicella, and vaccination of susceptible HCP, is being followed up meticulously. Conclusion Varicella can present with atypical symptoms, especially in the immunocompromised host. Suspected cases should be isolated until sensitive PCR studies are done. Varicella immune status of HCP should be assessed at recruitment and vaccination should be offered to susceptible individuals. Implementation and infection prevention and control measures can help prevent and mitigate varicella outbreaks within healthcare facilities.