Is Pneumocystis Jirovecii Transmitted by the Airborne Route?

      This paper is only available as a PDF. To read, Please Download here.


      Pneumocystis jirovecii (p.jirovecii) is a fungus responsible for causing opportunistic Pneumocystis pneumonia (PCP) in immunocompromised patients. Currently the Centers for Disease Control and Prevention (CDC) recommends following standard precautions while also avoiding placing a PCP patient in the same room with an immunocompromised patient. There has been recent scientific evidence that indicates P.jirovecii may be transmitted by the airborne route. The purpose of this literature review is to evaluate the recent research findings to assess whether escalating transmission-based precautions from droplet to airborne isolation is necessary to best prevent transmission of P.jirovecii in the immunocompromised oncologic patient population at a 514-bed inpatient comprehensive cancer center.


      PubMed was utilized to identify articles describing PCP outbreaks, the fungal characteristics, and mode of transmission. The articles reviewed comprised of systematic reviews, case control, and case report studies published between years 2016 through 2021, with one influential case control study published in 2010. The patient population studied in the outbreaks included those with heart, kidney, or liver transplants and patient populations with other immunocompromising conditions.


      Nine articles, including 4 systematic reviews, 4 case control studies, and 1 case report were reviewed. The scientific evidence of the fungal characteristics, mode of transmission, and occurrence of clusters of PCP cases favored the hypothesis that airborne transmission is possible. There are still some unknowns including the length of time that the fungal cysts can remain in the air and if the cysts are spread via droplet or aerosolized route.


      Despite the recent findings demonstrating possible airborne transmission, until further studies increase the strength of evidence for airborne transmission, droplet precautions should be considered for PCP patients to prevent transmission in the immunocompromised population.
      To read this article in full you will need to make a payment

      Purchase one-time access:

      Academic & Personal: 24 hour online accessCorporate R&D Professionals: 24 hour online access
      One-time access price info
      • For academic or personal research use, select 'Academic and Personal'
      • For corporate R&D use, select 'Corporate R&D Professionals'


      Subscribe to American Journal of Infection Control
      Already a print subscriber? Claim online access
      Already an online subscriber? Sign in
      Institutional Access: Sign in to ScienceDirect