Enterovirus infections
Enterovirus infections are caused by a group of viruses belonging to the Picornaviridae family, which includes echoviruses, coxsackie A and B viruses, and polioviruses. These viruses are among the most prevalent pathogens affecting humans, with approximately 10 to 15 million non-polio enterovirus infections occurring annually in the United States. Transmission typically occurs through the fecal-oral route or respiratory droplets, with newborns, children, and immunocompromised individuals being at higher risk. Symptoms can vary widely, ranging from mild flu-like signs to severe conditions such as myocarditis, encephalitis, and hepatitis, which can lead to long-term complications in rare cases.
Diagnosis is achieved through various sampling methods, including throat swabs and stool samples, with confirmation via virus isolation or genetic testing. While most infections resolve without treatment within a week, supportive care, hydration, and pain management may be recommended. Prevention strategies emphasize the importance of good hygiene practices, such as regular handwashing and proper sanitation, which can significantly reduce transmission. Vaccination efforts have largely eliminated poliovirus infections in the U.S., although there are concerns about decreasing vaccination rates affecting herd immunity. Overall, understanding enterovirus infections is crucial for managing their impact on public health, particularly among vulnerable populations.
Enterovirus infections
ANATOMY OR SYSTEM AFFECTED: All
ALSO KNOWN AS: Enteroviral sepsis syndrome
Definition
Enterovirus is a single-stranded RNA (ribonucleic acid) virus that belongs to the family Picornaviridae. The Enterovirus genus contains echoviruses, coxsackie A and B viruses, polioviruses, and the numbered enteroviruses. Enteroviruses are among the most common viruses causing disease symptoms in humans, although poliovirus has been eliminated in the United States. Approximately ten to fifteen million (nonpolio) enterovirus infections occur annually.
Causes
Enteroviruses are most commonly transmitted by the fecal-oral route or by the respiratory route. They also may be acquired during pregnancy through the placenta or during labor. Also, enteroviruses often are spread in hospitals because of improper handwashing or through contaminated equipment.
Risk Factors
Newborns, children, and immunocompromised persons are at greatest risk. Enterovirus infections may occur at any age, but the younger the person the greater the risk. Additional risk factors include prematurity, lower socioeconomic status, and poor sanitary living conditions. The majority of infections occur during the summer and fall seasons.
Symptoms
Symptoms depend on the type of enterovirus diagnosed. Common symptoms include a flu-like fever, upper respiratory tract infection, and lethargy. Symptoms also include irritability, poor feeding, and a rash. More severe symptoms are inflammation of the liver (hepatitis), pancreas (pancreatitis), heart (myocarditis), and brain (encephalitis); these infections place a person at an increased risk for long-term complications, such as liver dysfunction, neurological deficits, and mortality (although these complications are rare). Enteroviruses may also predispose a person to diabetes.
Screening and Diagnosis
Testing is performed by sampling through a throat or rectal swab or stool sample, or through cerebrospinal fluid. The diagnosis is confirmed by isolating the virus in cell culture. Reverse transcriptase-polymerase chain reaction (RT-PCR) is also becoming a popular genetic technique, with the benefit of a shorter turnaround time. Prenatal diagnostic tests, such as amniocentesis, may be available for specific types of enteroviruses.
Treatment and Therapy
Most infected persons have mild symptoms that do not require treatment because the infection independently resolves within one week. Medical care is provided based on specific symptoms. Some studies have shown benefits in antiviral treatments, such as pleconaril and immunoglobulin administration. Treatments include supporting the body's immune system and limiting symptoms by improving hydration, getting rest, and taking pain and fever medication.
Prevention and Outcomes
Poliovirus infections are very rare because of national immunization programs. Until 2022, the last reported case in the United States related to the virus and not the vaccine was in 1979. However, because of a decrease in vaccinations lowering herd immunity among American communities, a young adult in Rockland County, New York tested positive for vaccine-derived poliovirus type 2. The spread of enteroviruses may be reduced through universal hygiene practices, including handwashing, avoiding contact with contaminated items, and following vaccine schedule recommendations.
Bibliography
"About Non-Polio Enteroviruses." Centers for Disease Control, 11 Apr. 2024, www.cdc.gov/non-polio-enterovirus/about/index.html. Accessed 20 Oct. 2024.
Elfving, Maria, et al. “Maternal Enterovirus Infection during Pregnancy as a Risk Factor in Offspring Diagnosed with Type 1 Diabetes between 15 and 30 Years of Age.” Experimental Diabetes Research, 2008, p. 271958, doi:10.1155/2008/271958. Accessed 20 Oct. 2024.
Strauss, James, and Ellen Strauss. Viruses and Human Disease. 2nd ed., Academic Press/Elsevier, 2008.
Tebruegge, Marc, and Nigel Curtis. “Enterovirus Infections in Neonates.” Seminars in Fetal and Neonatal Medicine, vol. 14, no. 4, pp. 222–27, doi.org/10.1016/j.siny.2009.02.002. Accessed 20 Oct. 2024.
Zaoutis, Theoklis, and Joel D. Klein. “Enterovirus Infections.” Pediatrics in Review, vol. 19, no. 6, 1998, pp. 183-91, doi:10.1542/pir.19-6-183. Accessed 20 Oct. 2024.