CMV after transplant: What you need to know about prevention, symptoms, and treatment

When you get a new organ or stem cell transplant, your body is given powerful drugs to stop it from rejecting the gift. But those same drugs make you vulnerable to infections you used to fight off easily. One of the biggest threats is cytomegalovirus, a common herpesvirus that stays dormant in most people but can explode into a life-threatening infection after transplant. Also known as CMV, this virus doesn’t just cause fever and fatigue—it can attack your lungs, gut, liver, and even the new organ itself. About 30% to 70% of transplant patients get CMV reactivation, depending on their donor and recipient status. If you’re CMV-negative and get an organ from a CMV-positive donor, your risk jumps higher than most other groups. That’s why doctors watch you closely for months after surgery.

Immunosuppression, the intentional weakening of your immune system to protect your transplant, is the main reason CMV comes back. Drugs like tacrolimus, cyclosporine, and steroids keep your T-cells quiet—but they also let CMV slip through unnoticed. The virus can hide in white blood cells and wake up when your defenses are low. That’s why timing matters: the first 3 to 6 months after transplant are the danger zone. Symptoms like fever, night sweats, muscle aches, and diarrhea might seem mild, but they can signal something serious. Left untreated, CMV can lead to organ rejection, pneumonia, or colitis. Some patients even need to be hospitalized.

Thankfully, there are proven ways to fight back. Antiviral treatment, medications like valganciclovir and ganciclovir that stop CMV from multiplying is the standard. Some patients get it as a preventive measure—especially high-risk ones—while others start only after the virus shows up in blood tests. Monitoring your CMV levels with regular PCR tests is just as important as taking the pills. Skipping doses or stopping early can lead to drug resistance. And while these drugs work, they can also drop your white blood cell count, so your team has to balance the risks.

You’re not alone in this. Thousands of transplant patients manage CMV every year. The key is staying alert, sticking to your schedule, and speaking up if something feels off. Your care team isn’t just watching your lab numbers—they’re watching you. The posts below give you real, practical insights: how to spot early signs, what the latest guidelines say about long-term prevention, how CMV interacts with other drugs you’re taking, and what to do if treatment fails. These aren’t theory pieces—they’re based on what doctors and patients are dealing with right now. Whether you’re newly transplanted or years out, this collection gives you the clear, no-fluff facts you need to stay healthy.