About Adenovirus Infections
Adenoviruses - a group of viruses that infect the membranes
(tissue linings) of the respiratory tract, the eyes, the
intestines, and the urinary tract - account for about 10% of acute
respiratory infections in children and are a frequent cause of
diarrhea
.
Adenoviral infections affect infants and young children much
more frequently than adults. Child-care centers and schools
sometimes experience multiple cases of respiratory infections and
diarrhea that are caused by adenovirus.
Although these infections can occur at any time of the year,
respiratory tract disease caused by adenovirus is more common in
late winter, spring, and early summer. However, conjunctivitis and
pharyngoconjunctival fever caused by adenovirus tend to affect
older kids mostly in the summer.
The majority of the population will have experienced at least
one adenoviral infection by age 10. Although adenoviral infection
in kids can occur at any age, most take place in the first years of
life. Since there are many different types of adenovirus, repeated
adenoviral infections can occur.
Signs and Symptoms
Depending on which part of the body is affected, the signs and
symptoms of adenoviral infections vary:
Febrile respiratory disease
, which is an infection of the respiratory tract that includes a
fever
, is the most common result of adenoviral infection in children.
The illness often appears flu-like and can include symptoms of
pharyngitis (inflammation of the pharynx, or sore throat), rhinitis
(inflammation of nasal membranes, or a congested, runny nose),
cough, and swollen lymph nodes (glands). Sometimes the respiratory
infection leads to
acute otitis media
, an infection of the middle ear. Adenovirus often affects the
lower respiratory tract as well, causing
bronchiolitis
,
croup
, or viral
pneumonia
, which is less common but can cause serious illness in infants.
Adenovirus can also produce a dry, harsh cough that can resemble
whooping cough (pertussis)
.
Gastroenteritis
is an inflammation of the stomach and the small and large
intestines. Symptoms include watery diarrhea, vomiting, headache,
fever, and abdominal cramps.
Urinary tract infections
can cause frequent urination, burning, pain, and blood in the
urine.
Eye Infections:
-
Conjunctivitis
(or pinkeye) is a mild inflammation of the conjunctiva (membranes
that cover the eye and inner surfaces of the eyelids). Symptoms
include red eyes, discharge, tearing, and the feeling that
there's something in the eye.
-
Pharyngoconjunctival fever
, often seen in small outbreaks among school-age children, occurs
when adenovirus affects both the lining of the eye and the
respiratory tract. Symptoms include very red eyes and a severe
sore throat, sometimes accompanied by low-grade fever, rhinitis,
and swollen lymph nodes.
-
Keratoconjunctivitis
is a more severe infection that involves both the conjunctiva and
cornea (the transparent front part of the eye). This type of
adenoviral infection is extremely contagious, and occurs most
often in older children and young adults, who complain of red
eyes, photophobia (discomfort of the eyes upon exposure to
light), tearing, and pain.
Contagiousness
Adenovirus is highly contagious, as indicated by the occurrence
of multiple cases in situations of close contact, such as
child-care centers, schools, hospitals, and summer camps.
The types of adenovirus that cause respiratory and intestinal
infections spread from person to person through respiratory
secretions (coughs or sneezes) or fecal contamination. Fecal
material can be ingested through contamination of water supplies,
poor
hand washing
between the bathroom and the kitchen, eating food contaminated by
houseflies, or poor hygiene after handling diapers.
A child might also pick up the virus by holding hands or sharing
a toy with an infected person. Indirect transmission can occur
through exposure to the contaminated surfaces of furniture and
other objects.
The types of adenovirus causing conjunctivitis may
be transmitted by water (in lakes and swimming pools), by
sharing contaminated objects (such as towels or toys), or by
touch.
Once a child is exposed to adenovirus, symptoms can develop from
2 days to 2 weeks later.
Treatment
Adenoviral illnesses often resemble certain bacterial
infections, which can be treated with antibiotics. But antibiotics
don't work against viruses. To diagnose the true cause of the
symptoms so that proper treatment can be prescribed, your doctor
may want to test a sample of respiratory or conjunctival
secretions, a stool specimen, or blood or urine sample - depending
on what condition is being considered.
The doctor will decide on a course of action based on your
child's condition. Adenoviral infections usually don't
require hospitalization. However, infants and young children may
not be able to drink enough fluids to replace what they lose during
vomiting or diarrhea and may therefore need to be hospitalized to
correct or prevent dehydration. Also, young - especially premature
- infants with pneumonia usually need to be hospitalized.
In most cases, a child's body will get rid of the virus over
time. Because antibiotics are of no use in treating a viral
infection, you should simply try to make your child more
comfortable.
If your child has a respiratory infection or fever, getting
plenty of rest and taking in extra fluids is essential. A cool-mist
humidifier (vaporizer) may help loosen congestion and make your
child more comfortable. Be sure to clean and dry the humidifier
thoroughly each day to prevent bacterial or mold contamination. If
your child is under 6 months old, you may need to clear his or her
nose with a bulb syringe.
Don't give any over-the-counter (OTC) cold remedies or cough
medicines without checking with your child's doctor. You can
use acetaminophen to treat a fever; however, do
not
give aspirin because of the risk of
Reye syndrome
, a life-threatening illness.
If your child has diarrhea or is vomiting, increase fluid intake
and check with the doctor about giving an oral rehydration solution
to prevent
dehydration
.
To relieve the symptoms of conjunctivitis, use warm compresses
and a topical eye ointment or drops if your doctor recommends
them.
Duration
Most adenoviral infections last from a few days to a week.
Severe respiratory infections may last longer and cause lingering
symptoms, such as a cough. Pneumonia can last anywhere from 2 to 4
weeks.
In cases of pharyngoconjunctival fever, sore throat and fever
may disappear within a week, but conjunctivitis can persist for
another several days to a week. The more severe
keratoconjunctivitis can even last for several weeks. Adenovirus
can also cause diarrhea that lasts up to 2 weeks, which is longer
than other viral diarrheas.
Prevention
There's no way to completely prevent adenoviral infections
in kids. To reduce the risk of transmission, parents and other
caregivers should encourage frequent hand washing, keep shared
surfaces such as countertops and toys clean, and remove children
with infections from group settings until symptoms subside.
When to Call the Doctor
Most of these adenoviral conditions and their symptoms are also
associated with other causes. Call your doctor if:
- a fever continues more than a few days
- symptoms seem to get worse after a week
- your child has breathing problems
- your child is under 3 months old
- any swelling and redness around the eye becomes more severe
or painful
- your child shows signs of dehydration, such as appearing
tired or lacking energy, producing less urine or tears, or having
a dry mouth or sunken eyes
Remember that you know your child best. If he or she appears to
be severely ill, don't hesitate to call your doctor right
away.
Reviewed by:
Joel Klein, MD
Date reviewed: September 2006
Note: All information is for educational purposes only. For specific medical advice,
diagnoses, and treatment, consult your doctor.
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