Pneumocystis Infections Summary Pneumocystis jirovec is a tiny fungus that lives in the lungs of many people. Most people’s immune systems keep the fungus under control. But if your immune system is weak, the fungus can make you very sick. The most common problem of infection is pneumocystis pneumonia (PCP). PCP once was the major cause of death for people with HIV/AIDS. But now, it is possible to prevent or treat most cases. The key to surviving PCP is early treatment. The first signs of PCP are difficulty breathing, fever and a dry cough. If you have these symptoms, see your doctor right away. National Institute of Allergy and Infectious Diseases Find an Expert AIDSinfo Department of Health and Human Services Centers for Disease Control and Prevention Centers for Disease Control and Prevention National Institute of Allergy and Infectious Diseases National Institute of Allergy and Infectious Diseases Living With CD4 and CD8 American Association for Clinical Chemistry Clinical Trials ClinicalTrials.gov: Pneumocystis Infections National Institutes of Health Array Pneumocystis jiroveci pneumonia Start Here Pneumocystis Pneumonia Centers for Disease Control and Prevention Pneumocystis Pneumonia (PCP) New Mexico AIDS Education and Training Center Children Pneumocystis Pneumonia (For Parents) Nemours Foundation Related Issues Pneumocystis Pneumonia (PCP) and HIV American Academy of Family Physicians Diagnosis and Tests Pneumocystis Pneumonia Diagnosis and Testing Centers for Disease Control and Prevention Prevention and Risk Factors Pneumocystis Pneumonia Risk and Prevention Centers for Disease Control and Prevention Statistics and Research Pneumocystis Pneumonia Statistics Centers for Disease Control and Prevention Journal Articles Pneumocystis Infections Symptoms Symptoms of Pneumocystis pneumonia Centers for Disease Control and Prevention Treatments and Therapies Treatment and Outcomes for Pneumocystis Pneumonia Centers for Disease Control and Prevention