Enterovirus Infection During Pregnancy
Enteroviruses can also cause flu-like symptoms, rash, or in rare cases, inflammation of the heart (myocarditis) or brain (encephalitis). These viruses are also known causes of viral (sometimes called "aseptic") meningitis. Enterovirus infection is a particular risk during pregnancy since newborns infected with one of these viruses can, in rare instances, develop a severe and even potentially fatal illness.
What is a coxsackievirus?
Coxsackievirus is a member of the Picornaviridae family of viruses in the genus termed Enterovirus. Coxsackieviruses are subtype members of Enterovirus that have a single strand of ribonucleic acid (RNA) for its genetic material. The enteroviruses are also referred to as picornaviruses (pico means "small," so "small RNA viruses"). Coxsackie virus was first isolated from human feces in the town of Coxsackie, N.Y., in 1948 by G. Dalldorf. Coxsackie virus is also written as coxsackievirus in some publications.
What are the types of coxsackieviruses, and what can they cause?
Coxsackieviruses are separable into two groups, A (CVA) and B (CVB), which are based on their effects on newborn mice (coxsackievirus A results in muscle injury, paralysis, and death; coxsackievirus B results in organ damage but less severe outcomes.) There are over 24 different serotypes of the virus (having distinct proteins on the viral surface). Coxsackieviruses infect host cells and cause host cells to break open (lyse).
Picture of the coxsackievirus; SOURCE: CDC
Type A viruses cause herpangina (painful blisters in the mouth, throat, hands, feet, or in all these areas). Hand, foot, and mouth disease (HFMD) is the common name of this viral infection. Coxsackievirus A16 (CVA16) causes the majority of HFMD infections in the U.S. It usually occurs in children (age 10 and under), but adults can also develop the condition. This childhood disease should not be confused with the "foot and mouth disease" usually found in animals with hooves (for example, cattle, pigs, and deer). Type A viruses also cause inflammation of the eyelids and white area of the eye (conjunctivitis). Coxsackievirus A6 (CVA6) has caused herpangina (mouth blisters) in infants.
Type B viruses cause epidemic pleurodynia (fever, lung, and abdominal pain with headache that lasts about two to 12 days and resolves). Epidemic pleurodynia is also termed Bornholm disease. There are six serotypes of coxsackievirus B (1-6, with B 4 considered by some researchers as a possible cause of diabetes in a number of individuals).
Both types of viruses (A and B) can cause meningitis, myocarditis, and pericarditis, but these occur infrequently from coxsackievirus infections.
Enterovirus 71, like coxsackievirus, also causes HFMD. In Asia in July 2012, particularly Cambodia, children infected with enterovirus 71 (EV-71) had a high mortality rate due to encephalitis and acute polio-like paralysis. This epidemic (mainly in babies, toddlers, and children under 2 years of age).
Is the coxsackievirus contagious?
Yes, coxsackieviruses are contagious person to person. These viruses are transmitted mainly by the fecal-oral route and by respiratory aerosols. Droplets containing viruses that land on objects like toys or utensils may occasionally transmit the viruses indirectly to uninfected individuals.
How long are coxsackieviruses contagious?
Coxsackieviruses are most contagious during the first week of symptoms. However, viable virus microbes have been found in respiratory tracts for up to three weeks and then in feces up to eight weeks after initial infection, but during this time, the viruses are less contagious.
What is the incubation period for coxsackievirus infections?
The incubation period for coxsackievirus infections is relatively short; it lasts about one to two days with a range of about one to five days.
What are coxsackievirus infection symptoms and signs?
The most frequent signs and symptoms of coxsackievirus infections are initially fever, a poor appetite, and respiratory illness, including sore throat, cough, and malaise (feeling tired). This incubation period lasts about one to two days. Sore areas in the mouth develop in about a day or two after the initial fever and develop into small blisters that often ulcerate. Many infected people (usually children 10 years of age and younger) go on to develop a rash that itches on the palms of the hands and the soles of the feet. Other areas such as the buttocks and genitals may be involved. Some patients develop conjunctivitis. These symptoms usually last about seven to 10 days, and the person usually recovers completely. The individuals are most contagious for about a week after symptoms begin, but because the virus can be shed by the infected individual sometimes for weeks after the symptoms have gone away, the person may be mildly contagious for several weeks.
Infrequently, the infection may result in temporary fingernail or toenail loss (termed onychomadesis) and chest or abdominal muscle pain. Rarely, the disease may progress to cause viral meningitis (headache, stiff neck), myocarditis (heart muscle infection), pericarditis (inflammation/fluid collection of the tissue surrounding the heart), or encephalitis (brain inflammation).
Infection with EV-71 results in a higher incidence of neurologic involvement with symptoms such as a polio-like syndrome, meningitis, encephalitis, Guillain-Barré syndrome, and/or ataxia.
How do people get infected with coxsackievirus?
Infection usually is spread by fecal-oral contamination, although occasionally the virus is spread by droplets expelled by infected individuals. Items like utensils, diaper-changing tables, and toys that come in contact with body fluids that contain the virus may also transmit them to other individuals. Although people of any age, including adults, can get infected, the majority of patients with coxsackievirus infection are young children. Pregnant women can pass coxsackievirus to their newborns, which may cause serious problems for the newborn. So during pregnancy, women need to notify their obstetrician if they exhibit symptoms of the infection, especially if they are near their delivery date.
What are the risk factors for coxsackievirus infection?
Risk factors for coxsackievirus infection include physical contact with any patient with individuals with HFMD symptoms. Other risk factors include rural living conditions, association with children in child-care centers, and a large number of children in the family. Infectious virus can be found in feces, saliva, fluid in blisters, and nasal secretions. Even patients who have recovered and have no symptoms may still shed infectious virus for weeks. A fetus or newborn is at risk if their mother becomes infected near the delivery date. Pregnant women should avoid contact with HFMD patients. They should contact their OB/GYN physician if they develop any symptoms of HFMD.
What specialists treat coxsackievirus infections?
In most instances, if treatment is needed, it is done by the patient's pediatrician and/or primary-care physician. However, in severe cases, specialists in pediatric critical care and infectious diseases may be consulted. If severe complications develop (for example, carditis or pleurodynia), others like lung or cardiac specialists may be consulted.
How do physicians diagnose coxsackievirus infections?
Patients are usually diagnosed by their clinical appearance. Clinically, blisters that are painful usually on the hands, feet, and mouth in a child with fever are considered diagnostic of coxsackievirus infection. However, in rare instances, viral tests can be done to identify the virus, but the tests are expensive, usually need to be sent to a specialized viral diagnostic laboratory that uses RT-PCR, and often take about two weeks to get a result. This testing is almost never done since most infections are self-limited and typically mild, but this situation may change because of an outbreak in Alabama (38 children, 12% hospitalized but no deaths in 2011-2012) and the recent enterovirus 71 epidemic (about 905 of hospitalized children have died) in Cambodia. RT-PCR testing can distinguish between many viral genera, species, and subtypes. Distinguishing coxsackievirus strains from adenoviruses, other enterovirus types, echo virus, viruses causing mononucleosis, and other viral diseases may become necessary in the future.
Is there any treatment for coxsackievirus infection?
There is no specific treatment for this typically self-limited disease (the symptoms resolve without specific antiviral treatment in about two to 10 days). However, symptomatic treatment (acetaminophen [Tylenol]) that reduces fever and discomfort is currently recommended. Mouthwashes and sprays may lessen the oral discomfort. Fluids are also suggested to prevent dehydration, however, acidic juices may irritate the mouth ulcers. Home remedies like cold milk may sooth the oral discomfort. Some physicians use topical diphenhydramine (Benadryl)-containing gel or liquids to treat the hand and foot discomfort.
The relatively rare complications of coxsackievirus infections (for example, heart or brain infection) require special individualized treatments (possibly human immune globulin or specific antivirals, although such treatments are rare and not yet proved to be safe and effective with serious HFMD infections). These treatments are often administered by an infectious-disease doctor.
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Is it possible to prevent coxsackievirus infections?
Prevention of coxsackievirus infections is difficult but possible. With children, keeping strict hygienic precautions is almost impossible, but good practices such as hand washing after diaper changing or touching infected skin may reduce viral transmission to other family members. Attempts to regularly clean items that children contact, especially toys, pacifiers, and any items they may place in their mouths, may also reduce viral transmission. Hand washing, in general, is the best prevention technique. Currently, there is no commercial vaccine available.
Pregnant women should avoid contact with children (or adults) with HFMD because some studies suggest that coxsackievirus may cause developmental and other defects in the fetus.
Although infection and resolution of the disease usually renders the person immune to reinfection with the viral type that initiated the disease, the person is not immune to other coxsackievirus types. For example, a person may become immune to coxsackievirus type B4 but still would be susceptible to all of the other coxsackievirus types (for example, CVA16). In addition, other viruses such as enterovirus 71 and enteric cytopathic human orphan (ECHO) viruses can produce HFMD symptoms. Consequently, it is possible for some people to have multiple infections with HFMD symptoms even though repeated infections occur infrequently.
In 2014, Chinese scientists reported a successful phase 3 vaccine trial for prevention of EV-71 infections in infants and children. However, this vaccine is still considered experimental and is not commercially available in the U.S.
What is the prognosis of coxsackievirus infections?
Until recently, the general prognosis for most patients with coxsackievirus infections was excellent, with most children making a complete recovery without needing any supportive care (hospitalization). However, this prognosis may be changing as evidenced by the outbreak in Alabama in 2011-2012 that required 12% of children to be hospitalized for supportive care. Only rarely do patients suffer poor outcomes with complications of meningitis, pericarditis, or encephalitis. Unfortunately, infants and young children infected with EV-71 have a prognosis that may vary from good to poor.
Medically Reviewed on 10/23/2017
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