Investigation of Community Respiratory Viruses in Hematopoietic Stem Cell Transplant Patients and Household Member Characteristics

Background:

Community-acquired respiratory virus (CRV) infections are a threat to hematopoietic stem cell transplant (HSCT) outpatients. High mortality rates have been associated with CRV pneumonia. CRV is also responsible for unscheduled re-admissions, lengthy treatments, and increased medical costs. Graft versus host disease, immune status, and conditioning regimens were not associated with the development of CRV by the HSCT patient in previous studies.  In investigations of non-HSCT households, the presence of CRV infections and their spread were correlated with the presence of secondary family members. Therefore, the objectives of this study were to determine if children or the number of contacts living in the immediate household increase the risk of CRV acquisition in HSCT outpatients.

Methods: 

A descriptive correlational design with a retrospective medical record review of adult outpatients who received a HSCT between July1, 2006 and December 31, 2009 was performed. Respiratory viral cultures were followed for 24 months after date of transplant. Age of children <18 years and number of household members were obtained from the pre-transplant assessment. Summary statistics were used to describe sample characteristics. Binary logistic regression was used to determine whether the number of household member contacts or the number of children in each of three age groups was a significant predictor of CRV. Multivariate linear regression was used to investigate predictors of the number of CRV infections.

Results:

The sample (N= 720) had a mean age (SD) of 51.8 (12.4); 54% were in the allogeneic (allo) group, 44% in the autologous (auto) group, and other HSCT groups were 2%. Across all patients, children ages 0-4 years (p=.01) and 5-12 years (p=.001) predicted CRV infection.  The allo group had the greatest incidence of CRV infection (16%), and were most sensitive to the presence of young children.  Total number of household members was not a predictor of CRV.  The mean number of days to CRV infection for all groups was 283 days post-transplant. 

Conclusions:

Households with children in the age groups of 0-4 and 5-12 more than doubled the risk of an HSCT patient acquiring a CRV infection. Further studies are needed to test interventions designed to interrupt household transmission of CRV from children to the vulnerable HSCT patient. Household contacts, especially children, should be included in transplant teaching.  As indicated by the potentially high number of days between transplant and CRV infection, re-education and continuing focus on CRV prevention should be reinforced throughout the post-transplant period.

   *0-4   year age group p=.01

**5-12 year age group p=.001