Non-polio enteroviruses are a widespread group of viruses commonly found in the human gut. They frequently cause infection, impacting millions annually across the United States. These viruses circulate year-round, with increased prevalence during summer and fall. Most infected individuals experience no symptoms or only mild illness.
How Non-Polio Enteroviruses Spread and General Symptoms
Non-polio enteroviruses primarily spread through direct contact with an infected person or by touching contaminated objects and surfaces. The viruses are shed in an infected person’s feces, eye, nose, and mouth secretions, including saliva or mucus, and fluid from blisters. Transmission often occurs when individuals touch these contaminated sources and then touch their eyes, nose, or mouth without washing their hands.
The fecal-oral route is a common mode of transmission, particularly through practices like changing diapers or consuming contaminated drinking water. Respiratory droplets from coughing or sneezing can also spread some strains, though this is less common. Infected individuals can shed the virus for several weeks in their stool, even without symptoms, making prevention challenging.
Symptoms typically appear three to six days after exposure. Many infections result in mild, non-specific symptoms resembling a common cold, including fever, runny nose, sneezing, and cough. Individuals may also experience skin rashes, mouth blisters, and generalized body and muscle aches.
Other symptoms include headache, sore throat, and a general feeling of malaise. Gastrointestinal issues like vomiting, diarrhea, and abdominal pain can also occur. While many infections are asymptomatic or mild, infants, children, and teenagers are more likely to experience symptoms than adults, as they may not have developed immunity from prior exposures.
The Range of Illnesses They Cause
Non-polio enteroviruses can lead to a variety of specific illnesses, beyond general cold-like symptoms.
Hand-Foot-and-Mouth Disease (HFMD) is a common condition in young children. Symptoms include fever, followed by painful, blister-like sores in the mouth, often on the tongue, gums, and inside the cheeks. A characteristic rash of spots or blisters can also appear on the palms of the hands and soles of the feet, and sometimes on the buttocks or groin area.
Another illness is Herpangina, characterized by a sudden onset of high fever and painful, blister-like sores or ulcers. These lesions typically form in the back of the throat and on the roof of the mouth. Individuals with herpangina may also experience headache, sore throat, and a decreased appetite due to painful swallowing.
Viral meningitis, also known as aseptic meningitis, is an inflammation of the membranes surrounding the brain and spinal cord, and non-polio enteroviruses are a common cause. Symptoms include fever, headache, and a stiff neck. People may also experience sensitivity to light, nausea, vomiting, and irritability. This form of meningitis is less severe than bacterial meningitis and often resolves within 7 to 10 days.
Conjunctivitis, or “pinkeye,” can also result from infection, presenting as red, watery eyes. This inflammation of the conjunctiva, the thin membrane covering the eyeball and inner eyelid, may also include a burning sensation, grittiness, and crustiness around the eyelids upon waking. In rarer cases, acute hemorrhagic conjunctivitis can cause noticeable bleeding in the whites of the eyes and painful swelling.
Non-polio enteroviruses also frequently cause various respiratory illnesses. These can range from common colds with symptoms like runny nose, sneezing, and cough, to more severe conditions such as bronchitis. Enterovirus D68 (EV-D68), a specific type, is particularly known for causing respiratory illness, which can be mild or more serious, especially in children with asthma who may experience wheezing and difficulty breathing.
While most infections are mild, some non-polio enteroviruses can lead to rare, more serious complications. Myocarditis, an inflammation of the heart muscle, can cause symptoms such as new chest pain, shortness of breath, and irregular heartbeats. Encephalitis, which is inflammation of the brain, can manifest with symptoms ranging from lethargy and drowsiness to personality changes, seizures, or even coma. These severe conditions occur infrequently, highlighting the broad spectrum of illnesses these viruses can induce.
Identifying and Managing Infections
Diagnosis of non-polio enterovirus infections often relies on a healthcare provider’s assessment of symptoms and physical examination. In most mild cases, specific laboratory testing is unnecessary. However, for severe illness or symptoms like meningitis, a doctor may recommend laboratory tests to identify the specific virus.
Laboratory confirmation can involve molecular methods, such as polymerase chain reaction (PCR) assays, which detect viral RNA. Samples can be collected from sources including throat swabs, stool, or rectal swabs. For severe neurological involvement like meningitis, cerebrospinal fluid may be collected through a lumbar puncture. A positive test from respiratory or rectal swabs does not always mean the virus is the cause of illness, as these viruses can be shed for weeks after symptoms resolve.
No specific antiviral treatment is available for most non-polio enterovirus infections. Treatment primarily focuses on supportive care to alleviate symptoms and promote recovery. Supportive care includes rest, hydration, and over-the-counter medications for fever and pain.
Seek medical attention if symptoms worsen or become severe. Consult a healthcare provider for symptoms like severe headache, stiff neck, difficulty breathing, or signs of dehydration. Infants and individuals with weakened immune systems are at higher risk for serious complications and require close monitoring.
Protecting Yourself and Others
Preventing non-polio enterovirus spread centers on diligent hygiene, as no vaccine is available.
Frequent, thorough handwashing with soap and water is a primary defense. Wash hands for at least 20 seconds, especially after using the bathroom, changing diapers, and before preparing or eating food.
Avoid touching eyes, nose, and mouth with unwashed hands to prevent virus entry. Clean and disinfect frequently touched surfaces and shared items like doorknobs, toys, and countertops to reduce virus presence. These viruses can survive on surfaces for several days.
Limit close contact with sick individuals to reduce transmission. Avoid hugging, kissing, or sharing eating utensils and glasses. Stay home from work, school, or childcare when symptomatic to prevent further spread.