AI Summary Infection is one of the most common serious complications after liver transplant, and cytomegalovirus (CMV) is the most common infectious complication after any solid-organ transplant.
Medically reviewed.
After a liver transplant, the medicines that protect your new liver from rejection also weaken your immune system's ability to fight germs. This makes bacterial, viral, and fungal infections a common and serious complication, especially in the first year after surgery. Infections that a healthy immune system would clear on its own can become serious, so your transplant team watches for them closely.
Knowing the warning signs and prevention steps can help you catch infections early and stay well. This page explains the main types of infection, when your risk is highest, what raises it, and the everyday habits and preventive medicines that lower it.
Liver Health AI Assistant
Ask Aimy
Aimy answers from LiverDirectory’s reviewed health information — helping patients make sense of liver-health terms, prepare for specialist visits, and explore what to look up next.
About infection after transplant
Liver transplant recipients take immunosuppressive medicine for life to keep the immune system from attacking the new liver. These medicines are necessary, but they also make it harder for the body to fight off bacteria, viruses, and fungi. This raises the risk of infections that a healthy immune system would normally clear without trouble.
Infection is one of the most common serious complications after liver transplant surgery. It is a leading cause of illness and death in the early period after surgery. Your transplant team monitors closely for infection because catching it early makes treatment easier and protects your new liver.
Infection risk changes over time. It is highest in the weeks right after surgery, when incisions are healing and immunosuppression is strongest, then gradually eases as medicine doses are lowered and the body adjusts.
Bacterial, viral, and fungal
Weakened immunity from anti-rejection medicine lets bacteria, viruses, and fungi cause infections more easily than they would without a transplant.
Warning signs
Fever and chills are often the first sign that your body is fighting an infection. Because your medicines weaken your immune response, you may not feel very sick even when an infection is developing. For that reason, check your temperature each day and write it down. Call your transplant team if you have a fever, or if chills or a high temperature do not go away.
Some soreness at your incision is normal while it heals. Watch for redness that spreads, swelling, warmth, drainage, or pain that gets worse instead of better. Any of these can mean the wound is infected. Look at your incision every day, and tell your team about changes right away.
A new or worsening cough, shortness of breath, or chest discomfort can point to pneumonia or another lung infection. Do not assume it is a simple cold, because infections can move quickly when your immune system is suppressed. Report breathing symptoms early, even if they seem mild.
Pain or burning when you urinate, cloudy or foul-smelling urine, or needing to urinate more often can signal a urinary tract infection. Some people also notice red or brown urine. Urinary infections are common after transplant, and they are easier to treat when found early.
Feeling tired is common during recovery, but unusual tiredness that does not improve with rest needs attention. Extreme fatigue can be an early sign of a viral infection such as CMV. CMV can also cause muscle aches and swollen lymph nodes. Tell your team if you feel unwell in a way you cannot explain.
Sudden nausea, vomiting, or diarrhea that does not pass quickly can come from an infection, including CMV, or from a food-related illness. These symptoms can also be side effects of medicine, so your team may need to check the cause. Diarrhea and vomiting can also leave you short on fluids, so call your team rather than waiting it out.
If you notice any of these signs, contact your transplant team right away rather than waiting for your next scheduled visit. Keeping a simple notebook of symptoms, daily temperatures, and questions helps you describe changes clearly. Early treatment is far easier than treating an infection that has spread.
Risk factors
Some risk comes from the medicines that protect your transplant; other risk factors are things you and your team can actively manage.
Many everyday exposures are avoidable. Combined with your prescribed preventive medicines, simple daily habits meaningfully lower your chance of infection.
Prevention and monitoring
Wash your hands often and thoroughly, especially before eating and after being in public places. Ask household members to do the same.
Avoid close contact with anyone who has a cold, flu, or other contagious illness when possible, and consider wearing a mask in crowded or high-exposure settings, especially in the first 3 months after surgery.
Your transplant team may prescribe antiviral medicine (such as valganciclovir) to prevent CMV, an antibacterial medicine (such as trimethoprim/sulfamethoxazole) to prevent pneumocystis pneumonia, and an antifungal medicine (such as fluconazole) to prevent candida infections. Take these exactly as prescribed for the full course, even if you feel well.
Keep every lab and follow-up appointment. Blood tests can detect CMV and other infections before symptoms appear, which allows treatment to start earlier.
Eating Habits After Transplant
Immunosuppressive medicine makes foodborne illness more dangerous, since your body cannot fight off bacteria and parasites from food as effectively as before. A few simple kitchen habits lower that risk without requiring a restrictive diet.
Beyond food safety, a liver-friendly diet of fresh, balanced meals supports your recovery and overall transplant health. Small, frequent meals can also help if your appetite is reduced by medicine.
Food Safety Steps
COMMON QUESTIONS
Your immunosuppressive medicine weakens your immune system. You need this medicine to keep your body from rejecting the new liver, but it also makes it harder to fight bacteria, viruses, and fungi. Infections that a healthy immune system would clear on its own can become serious. This is an expected tradeoff of transplant, not a sign that anything went wrong. Your team balances the dose to protect your liver while keeping infection risk as low as possible, and they monitor you closely, especially in the first months.
Risk is highest in the first six months. In the first month, infections mostly come from the surgery itself, such as wound infections, pneumonia, and infections linked to catheters or drains. Between about one and six months, immunosuppression is strongest, so opportunistic infections such as CMV, other viral reactivations, and fungal infections become the main concern. After six months, the risk from the transplant itself declines. Your immune response stays weaker than average, though, so colds, flu, and urinary tract infections still need prompt attention.
Cytomegalovirus (CMV) is a common virus that is the most common infectious complication after a solid-organ transplant. It is present in more than half of the US population and stays dormant for life, rarely causing symptoms in healthy people. After transplant, weakened immunity can let it reactivate. Your risk is higher if your donor liver is CMV-positive and you are CMV-negative. Your team may prescribe an antiviral medicine to prevent CMV and use blood tests to detect it before symptoms appear, so treatment can start early.
Call your transplant team right away if you notice any warning sign, rather than waiting for your next appointment. These include fever or chills, redness, swelling, or drainage at your incision, a new or worsening cough or shortness of breath, pain or burning when you urinate, unusual tiredness that does not improve with rest, or sudden nausea, vomiting, or diarrhea that does not pass quickly. Early treatment is far easier than treating an infection that has spread.
Yes. Preventive medicine works before an infection starts, so you take it even when you feel well. Your team may prescribe an antiviral such as valganciclovir, an antibacterial such as trimethoprim/sulfamethoxazole, and an antifungal such as fluconazole. Typical courses run from several weeks to several months, and your team sets the length based on your risk. Take each medicine exactly as prescribed and finish the full course. Some of these medicines need regular blood tests, so keep every lab appointment.
Yes, in most cases. Inactivated vaccines are generally safe after transplant, although your immune response to them may be weaker because of your medicines. Live vaccines are usually avoided because they can cause illness in people with weakened immunity. Vaccines work best when given before transplant, so ideally your series is finished before surgery. If a series was started but not finished, your team may complete it three to six months after transplant, and a flu vaccine may be possible as early as one month after. Always check with your transplant team before getting any vaccine.
Simple kitchen and daily habits lower your risk without a restrictive diet. Cook meat to at least medium-well, and avoid raw fish, sushi, undercooked eggs, and raw or undercooked shellfish. Wash fresh fruits and vegetables thoroughly, and avoid unpasteurized dairy products, juices, and honey. Avoid grapefruit and grapefruit juice, which can interact with immunosuppressive medicines. Beyond food, wash your hands often, limit contact with people who are sick, and ask your team about swimming and gardening in the first months after surgery.
Medical disclaimer: LiverDirectory provides educational information and a directory of providers. It does not provide medical advice, diagnosis, or treatment. Always consult a licensed physician regarding any medical condition.
