7 Key Signs of Cytomegalovirus (CMV) Infection You Should Know

Cytomegalovirus (CMV) infection is a common viral infection caused by a member of the herpesvirus family. While many people with CMV infection experience no symptoms at all, certain groups—including newborns, people with weakened immune systems, and occasionally healthy adults—can develop noticeable signs of illness. Understanding the symptoms of CMV infection is crucial for early detection and appropriate medical care, particularly for vulnerable populations.

CMV is remarkably common, with studies suggesting that over half of adults by age 40 have been infected at some point. The virus remains dormant in the body after initial infection and can reactivate when the immune system becomes compromised. In this article, we’ll explore the primary symptoms of CMV infection across different patient populations, helping you recognize when medical attention may be necessary.

1. Flu-Like Symptoms in Healthy Adults

When healthy adults develop symptomatic CMV infection, the presentation often resembles infectious mononucleosis or a prolonged flu-like illness. This is one of the most common manifestations in immunocompetent individuals who acquire the virus.

Common characteristics include:

• Persistent fever that may last for several weeks
• Profound fatigue and general malaise
• Muscle aches and body soreness
• Sore throat and mild respiratory symptoms
• Swollen lymph nodes, particularly in the neck

These symptoms typically develop 2-4 weeks after initial exposure to the virus and can persist for 2-6 weeks. Most healthy individuals recover fully without specific treatment, though fatigue may linger for several months. The similarity to other common illnesses means CMV infection often goes undiagnosed in this population unless specific testing is performed.

2. Congenital CMV Signs in Newborns

Congenital CMV infection occurs when a baby is infected with the virus before birth, typically through transmission from the mother during pregnancy. This represents the most serious form of CMV infection, as it can cause significant complications in developing infants.

Newborns with congenital CMV may exhibit:

• Low birth weight and premature delivery
• Jaundice (yellowing of the skin and eyes)
• Enlarged liver and spleen (hepatosplenomegaly)
• Purple skin rashes or petechiae (small purple spots)
• Microcephaly (abnormally small head size)
• Seizures or other neurological abnormalities

It’s important to note that approximately 90% of babies born with congenital CMV infection show no symptoms at birth. However, some of these children may develop hearing loss, vision problems, or developmental delays months or years later. Early detection through newborn screening can be crucial for monitoring and early intervention.

3. Prolonged Fever and Night Sweats

One of the hallmark symptoms of active CMV infection, particularly in immunocompromised patients, is persistent fever that doesn’t respond well to standard fever-reducing medications. This fever pattern can be quite distinctive and often serves as an early warning sign of CMV disease.

The fever associated with CMV infection typically has these characteristics:

• Temperature ranging from 38°C to 40°C (100.4°F to 104°F)
• Intermittent or continuous pattern lasting weeks
• Accompanied by drenching night sweats
• May be the only symptom in early infection

In transplant recipients or people with HIV/AIDS, unexplained fever persisting beyond a few days should prompt evaluation for CMV infection. The night sweats can be severe enough to require changing bedclothes and sheets, significantly impacting quality of life and sleep patterns.

4. Gastrointestinal Manifestations

CMV can cause significant gastrointestinal symptoms, particularly in individuals with compromised immune systems. The virus has a particular affinity for the gastrointestinal tract and can cause inflammation throughout the digestive system from the esophagus to the colon.

Digestive symptoms may include:

• Severe abdominal pain and cramping
• Chronic diarrhea, sometimes bloody
• Difficulty or pain when swallowing (dysphagia)
• Nausea and vomiting
• Loss of appetite and unintended weight loss
• Gastrointestinal bleeding in severe cases

CMV colitis (inflammation of the colon) and CMV esophagitis (inflammation of the esophagus) are particularly common in AIDS patients with very low CD4 counts and in organ transplant recipients. These conditions can lead to ulcerations in the digestive tract, which may cause bleeding and perforation if left untreated. The abdominal pain can be diffuse or localized and may mimic other gastrointestinal conditions, making diagnosis challenging.

5. Vision Problems and Eye Inflammation

CMV retinitis is a serious complication that primarily affects individuals with severely weakened immune systems, particularly those with advanced HIV/AIDS or those taking immunosuppressive medications after organ transplantation. This condition can lead to permanent vision loss if not detected early.

Eye-related symptoms include:

• Blurred or decreased vision
• Floaters (spots or “cobwebs” in the visual field)
• Blind spots or scotomas
• Light flashes or photopsia
• Progressive vision loss, often starting peripherally
• Usually affects one eye initially but can spread to both

CMV retinitis typically begins in the peripheral retina and progressively moves toward the center of vision. The characteristic appearance on eye examination shows areas of retinal necrosis with hemorrhage, often described as having a “pizza pie” or “cottage cheese and ketchup” appearance. Because early symptoms may be subtle, regular ophthalmologic screening is recommended for high-risk individuals. Any new vision changes in immunocompromised patients should be treated as a medical emergency requiring immediate evaluation.

6. Respiratory Symptoms

While less common than other manifestations, CMV can affect the respiratory system, particularly in transplant recipients and other immunocompromised individuals. CMV pneumonitis (lung inflammation) is a serious complication that can be life-threatening if severe.

Respiratory symptoms may present as:

• Persistent dry cough
• Shortness of breath (dyspnea), especially with exertion
• Rapid or labored breathing
• Low oxygen levels in the blood
• Chest discomfort or pain
• Progressive respiratory decline

CMV pneumonitis is particularly concerning in lung transplant recipients and bone marrow transplant patients, where it can develop rapidly and severely. The condition often occurs in conjunction with other organ involvement and may be difficult to distinguish from other opportunistic infections or transplant rejection. Symptoms can range from mild respiratory complaints to severe respiratory failure requiring mechanical ventilation.

7. Neurological Complications

CMV can affect the nervous system, causing a range of neurological symptoms that vary depending on which part of the nervous system is involved. These complications are most common in immunocompromised individuals and infants with congenital infection.

Neurological manifestations include:

• Encephalitis (brain inflammation) causing confusion, altered mental status, or lethargy
• Seizures or epileptic episodes
• Headaches, often severe and persistent
• Weakness or paralysis in extremities
• Difficulty with coordination and balance
• Radiculopathy causing nerve pain or numbness
• Cognitive difficulties or memory problems

CMV encephalitis can cause progressive cognitive decline, personality changes, and decreased level of consciousness. In people with AIDS, CMV can cause ventriculoencephalitis, affecting the brain’s ventricles. Polyradiculopathy, where CMV affects the nerve roots of the spinal cord, can cause rapidly progressive weakness, numbness, and bladder or bowel dysfunction. In congenital CMV infection, neurological damage can result in developmental delays, intellectual disabilities, cerebral palsy, and epilepsy that may not become apparent until months or years after birth.

Main Causes of CMV Infection

Understanding how cytomegalovirus spreads is essential for recognizing risk factors and taking appropriate precautions. CMV is transmitted through various bodily fluids and can spread in multiple ways:

Primary transmission routes include:

• Direct contact with infected bodily fluids: CMV spreads through saliva, urine, blood, tears, semen, vaginal fluids, and breast milk. Close contact with these fluids from an infected person is the most common transmission method.
• Sexual transmission: The virus can be transmitted through sexual contact, making it similar to other sexually transmitted infections in this regard.
• Mother-to-child transmission: Pregnant women can pass CMV to their unborn babies through the placenta, during delivery through contact with vaginal secretions, or after birth through breast milk. This is the leading cause of congenital CMV infection.
• Blood transfusions and organ transplants: Recipients of blood products or solid organ transplants can acquire CMV from infected donors, which is why screening is important in these settings.
• Childcare settings: Young children, particularly those in daycare, frequently shed CMV in their urine and saliva. Caregivers and parents can become infected through contact with these fluids during diapering, feeding, or wiping noses.
• Occupational exposure: Healthcare workers and childcare providers have increased exposure risk due to contact with infected patients or children.

The virus can remain dormant in the body after initial infection and reactivate when the immune system becomes weakened due to illness, medications, or other factors. Reactivation is a common cause of CMV disease in transplant recipients and people with HIV/AIDS.

Prevention Strategies

While there is currently no vaccine available for CMV, several practical measures can significantly reduce the risk of infection, particularly for those most vulnerable to serious complications.

Essential prevention practices:

• Rigorous hand hygiene: Wash hands thoroughly with soap and water for at least 20 seconds, especially after changing diapers, feeding young children, wiping noses, or handling children’s toys. This is the single most effective prevention measure.
• Avoid sharing personal items: Don’t share eating utensils, drinking glasses, toothbrushes, or other items that come in contact with saliva, particularly with young children or anyone who might be infected.
• Careful handling of children’s items: Pregnant women and immunocompromised individuals should be especially cautious when handling items contaminated with children’s saliva or urine, including toys, pacifiers, and changing tables.
• Safe sexual practices: Use barrier protection methods during sexual activity, particularly if you or your partner have risk factors for CMV infection.
• Screening in healthcare settings: Blood and organ donors should be screened for CMV, and when possible, CMV-negative products should be used for high-risk recipients such as premature infants and transplant patients.
• Pregnancy precautions: Pregnant women, especially those working in childcare or healthcare settings, should be meticulous about hygiene practices. Some may consider avoiding close contact with young children’s saliva and urine during pregnancy.
• Monitoring for transplant recipients: People who have received organ transplants should undergo regular monitoring for CMV infection and may receive preventive antiviral medications as prescribed by their healthcare provider.
• Workplace safety: Healthcare workers should follow standard precautions when handling bodily fluids and use appropriate personal protective equipment.

For high-risk individuals, such as transplant recipients or people with HIV/AIDS, healthcare providers may recommend additional preventive strategies. If you’re pregnant or immunocompromised and have concerns about CMV exposure, consult your healthcare provider for personalized guidance.

Frequently Asked Questions

Can healthy people get sick from CMV?

Yes, but most healthy people with CMV infection experience either no symptoms or mild flu-like symptoms that resolve on their own. The immune system in healthy individuals typically keeps the virus under control. Serious complications from CMV are rare in people with normal immune function.

How long does CMV infection last?

The initial symptomatic phase of CMV infection in healthy adults typically lasts 2-6 weeks, though fatigue may persist for months. However, once infected, the virus remains in your body for life in a dormant state. It can reactivate if your immune system becomes weakened.

Is CMV contagious?

Yes, CMV is contagious and spreads through contact with infected bodily fluids including saliva, urine, blood, tears, semen, vaginal fluids, and breast milk. However, transmission requires close, intimate contact and is not spread through casual contact like shaking hands or being in the same room.

Who is at highest risk for serious CMV complications?

Babies infected before birth (congenital CMV), people with weakened immune systems (including those with HIV/AIDS, transplant recipients, and cancer patients receiving chemotherapy), and premature infants are at highest risk for serious complications from CMV infection.

How is CMV infection diagnosed?

CMV infection is diagnosed through blood tests that detect antibodies to the virus or the virus itself (through PCR testing). In newborns, diagnosis can be made through urine or saliva testing within the first three weeks of life. For specific organ involvement, tissue biopsy or specialized tests may be necessary.

Can CMV cause hearing loss?

Yes, CMV is the leading infectious cause of hearing loss in children. Hearing loss from congenital CMV can be present at birth or develop later in childhood. It may affect one or both ears and can range from mild to profound. This is why hearing screening and monitoring are crucial for babies diagnosed with congenital CMV.

Can you get CMV more than once?

While you typically don’t get re-infected with the same strain of CMV, you can be infected with different strains. Additionally, the dormant virus in your body can reactivate, especially if your immune system becomes compromised. Reactivation is common in transplant recipients and people with advanced HIV/AIDS.

Should pregnant women be tested for CMV?

Routine CMV screening is not currently recommended for all pregnant women in most countries, as there is no proven treatment to prevent transmission to the baby. However, pregnant women should practice good hygiene, especially if they work with young children. Testing may be recommended if you have symptoms suggesting CMV infection or if ultrasound findings suggest possible fetal infection.

References:

• Centers for Disease Control and Prevention – Cytomegalovirus (CMV) and Congenital CMV Infection
• Mayo Clinic – Cytomegalovirus (CMV) infection
• NHS – Cytomegalovirus (CMV)
• World Health Organization – Cytomegalovirus
• National Center for Biotechnology Information – Cytomegalovirus