Community acquired respiratory and gastrointestinal viral infections: challenges in the immunocompromised host.

PURPOSE OF REVIEW: Newer molecular diagnostic techniques have advanced the field of clinical microbiology and infectious diseases, particularly with respect to characterizing the role that community acquired viruses play in the clinical course and outcomes of the immunocompromised host. This review will examine recent studies describing the impact of adenovirus, rhinovirus, hepatitis E and norovirus in the course of solid organ and stem cell transplant recipients, as well as their epidemiology and implications for infection prevention and control.

RECENT FINDINGS: Adenovirus transmission is poorly understood; recent studies increasingly point to reactivation of latent infection in the immunocompromised host. Rhinovirus shedding can persist for weeks after acute viral infection, complicating hospital infection control policies. Hepatitis E is increasingly recognized as a potential pathogen in the stem cell and solid organ transplant population, and should be considered in the work-up for unexplained liver function test abnormalities. Similar to rhinovirus, norovirus shedding from the gastrointestinal tract may persist for months in the immunocompromised host; infected patients are at a higher risk for transmitting norovirus compared with infected healthcare workers.

SUMMARY: Additional studies are needed, particularly with respect to transmission, for these community acquired viral infections, which often have devastating consequences in the immunocompromised patient population.