Adenovirus, what are they?

Human adenoviruses (AdvH) are DNA viruses of which more than 60 serotypes grouped into seven species (A-G) have been described, causing infection in humans. Adenoviruses are a group of viruses that can infect membranes (lining tissues).

They usually cause benign and self-limited processes therefore, they cannot and usually are not diagnosed specifically. This is the reason why we do not have data on the prevalence and incidence of these infections. They are not seasonal virusesThey can infect at any time of the year, cause local outbreaks and live long on surfaces.

Adenoviruses are the cause of infectious diseases, especially of the upper respiratory tract and, less frequently, they cause gastrointestinal, ophthalmological, genitourinary and neurological infections. Symptoms are impossible to distinguish from infections caused by other respiratory viruses. Furthermore, adenoviruses are capable of mimicking serious bacterial infections.

Contagion by adenovirus

Adenovirus in children under five years of age is common, since they are highly contagious and spread easily. Transmission is by aerosol droplets, fecal-oral, and contaminated objects; less frequently, via the birth canal and in donor kidney and liver transplants.

Their infections are frequent in places where there is direct contact between people, such as day care centers, schools, hospitals or summer camps. For example, outbreaks of pharyngoconjunctival fever in summer camps are associated with contaminated water in swimming pools or lakes.

As to the gravity of the infection has been related to serotypes 7, 5, 14 and 21. The clinical manifestations of infection by adenoviruses depend on the age and immune status of the child.

Immunosuppressed patients can have very serious adenovirus infections, especially hematopoietic cell or solid organ transplant recipients. Children suffering from malnutrition and newborns are also at risk groups for developing serious disease.

Symptoms

The signs and symptoms of adenovirus infections vary depending on the type of adenovirus and the part of the body affected. respiratory symptoms are the most frequent and they usually appear two days to two weeks after exposure to adenovirus.

Most adenovirus infections last from a few days to a week or two. Severe infections can last longer and cause persistent symptoms, such as a cough.

Depending on the adenovirus serogroup, they cause:

• Serogroup A: It has been associated with the gastrointestinal tract.
• Serogroup B: with the respiratory tract and conjunctivitis.
• Serogroup D:
• Serogroup E: respiratory and eye infections.
• Serogroups F and G:

Depending on the serotype, they cause:

• respiratory: pharyngitis, colds (serotypes 1, 2, 3, 4, 5, 7 and 21),, pneumonia (serotypes 1, 2, 3, 4, 5, 7, 14 and 21), acute otitis media, pertussis syndrome, respiratory syndrome severe acute (serotypes 3, 4, 7, 11, 14 and 21).
• Eyepieces: pharyngoconjunctival fever (serotypes 3 and 7), epidemic keratoconjunctivitis (serotypes 8, 19 and 37) and conjunctivitis (serotype 3).
• gastrointestinal: infantile gastroenteritis (serotypes 40 and 41), mesenteric adenitis, hepatitis (serotype 5).
• Renal: Hemorrhagic cystitis, interstitial nephritis (serotypes 11, 34 and 35), urethritis.
• Neurological: (serotype 7), encephalitis (serotype 7).
• Other: disseminated disease, myocarditis, myositis with rhabdomyolysis, arthritis.

Diagnosis

The symptoms of adenovirus infections they are similar to the infections of many other viruses, that is, they present nonspecific symptoms. That's the reason why they are almost never diagnosed.

Only when a child has a severe infection, pediatricians do tests using their respiratory or conjunctival secretions, or a blood, stool or urine sample to confirm the diagnosis. In cases of suspected local outbreak (for example, in a school), screening tests are also carried out.

Treatment

The majority of adenovirus infections get better on their own and they are self-limited in time, so they do not need a specific treatment. Treatment will be similar to any other viral infection: antipyretic, rest and good hydration.

Children who are immunosuppressed or with severe infections may need antiviral medications and hospital admission.

Can adenovirus infections be prevented?

To help reduce the spread of adenovirus infections you should:

• Perform a correct handwashing.
• Keep clean shared surfaces (such as tables and toys).
• Prevent let infected children enter contact with the rest of the group until your symptoms subside.
• Teaching children to cough and sneeze on the sleeve of the shirt, on the elbow or on tissues and not in the hand.

Is there a vaccine for adenovirus?

Currently the vaccine is only available to the US military. They are oral vaccines against adenovirus types 4 and 7, which were approved by the US Food and Drug Administration (FDA) in March 2011.

• They mostly affect children under the age of five, are highly contagious, and spread easily.
• The symptoms of adenovirus infections are similar to those of many other viruses, that is, they present nonspecific symptoms. That is why they are almost never diagnosed.
• Adenoviruses cause infectious diseases in young children, especially of the upper respiratory tract, and less frequently, they cause gastrointestinal, ophthalmologic, genitourinary, and neurologic infections.

Teladoc Pediatric Specialist