|Photo by: NIAID via Wikimedia Commons|
Influenza viruses continue to spread illness and have included the State of Missouri in the list of affected states in the US. At least 40,000 cases and more than 600 flu-related deaths were reported by the Missouri Department of Health and Senior Services since October 1. But there is another virus that acts and spreads infection like influenza – the adenovirus.
Adenoviruses are members of the Adenoviridae family that contain a double-stranded DNA genome. There are more than 50 well-defined adenoviral serotypes that can cause illnesses in humans. The illnesses can range from mild infections to life-threatening multi-organ diseases, particularly among people with a compromised immune system. With the current influenza season, adenoviruses can blend perfectly to cause illness and be confused with the common cold or the flu.
“Unless you look for it or you suspect it’s circulating or you are using diagnostic testing capabilities that can tell it apart, you are going to miss it, especially during flu season,” said Dr. Adriana Kajon, an infectious disease specialist at the Lovelace Respiratory Research Institute in New Mexico.
An infection caused by the adenovirus often manifest as a respiratory illness with symptoms such as a cough, headaches, body pains, and fever. However, not all cases of adenovirus infection have a cough or respiratory symptoms. Some adenoviruses can infect other parts of the body including the eyes that can lead to conjunctivitis or pink eye, the gastrointestinal tract that can lead to gastroenteritis, and the spinal cord that can lead to neurological infection. Other illnesses that can be caused by the virus include:
- Sore throat: A condition caused by an injury, irritation or trauma of the throat due to infections or toxins.
- Bronchitis: A condition wherein the lungs become filled with mucus, causing breathing difficulties.
- Cystitis: A condition in which the urinary bladder is inflamed because of a bacterial infection or urinary tract infection. But viruses can also cause urinary bladder infections.
Because it can cause flu-like symptoms, the United States military force vaccinates the recruits to protect them from two major strains, which are type 4 and type 7. According to the Centers for Disease Control and Prevention, the two strains can cause severe outbreaks of respiratory problems among recruits. The virus can easily spread through the air by coughing or sneezing from one person to another. It can also spread through direct physical contact between a carrier and a healthy person.
“That’s a big deal, especially for a disease that by all means is vaccine preventable. But this vaccine is not licensed to be used in civilians,” said Dr. Kajon.
Adenovirus infection can also happen outside the military like what happened to the 10 people who died in the 2007 outbreak. But because the outbreak is more common in the military, the vaccine is not available to the public. Dr. Kajon and colleagues investigated recent outbreaks of the virus. They gathered data from colleges, nursing homes, and elsewhere for the details of adenovirus outbreaks from 2011 to 2015. They found that during the severe influenza epidemic of the 2014-2015 season, about 13 people out of 168 students had adenovirus infections after testing college students at one campus.
While most patients do not suffer from adenoviruses, some people suffer from far worse conditions than expected. The research team led by Dr. Kajon found the following moderate to severe cases of adenovirus infections:
- A 43-year-old female in Rochester, New York contracted the virus in 2012. Her health rapidly declined that led to pneumonia and respiratory failure. She also suffered from cerebral edema or brain swelling and bleeding during her hospital stay. For a month, she was on a ventilator to help her breathe, and after one year, she still suffers breathlessness with too much physical exertion.
- A 26-year-old male in Connecticut suffered from the adenovirus in 2011. He had chills, nausea, and vomiting. He needed to stay in the hospital for days to recover from the viral infection.
|Adenovirus infection / Photo by: Yale Rosen via Flickr|
While adenoviruses are not true killers like influenza, which is capable of putting at least 70,000 people in the hospital, they are very difficult to treat. Adenoviruses can survive for a month on numerous surfaces, whether plastic or metal. Hospitals also do not have a good set of treatment against it and only depend on the antiviral called cidofovir, which can only help some people with severe adenovirus infection.
“This is a vaccine-preventable disease. A life is a life. Losing a loved one to viral pneumonia when you know it could have been prevented is hard. Unfortunately, it all comes down to the perception of having a market,” said Dr. Kajon.
One serotype of the adenovirus known as Ad14 can cause potentially fatal viral infections. The serotype has been identified in the US in 2005. It is a rare and emerging serotype that already caused infections in at three events:
1. Clusters of people in Oregon in 2007 and in Alaska in 2008 who suffered pneumonia. According to the CDC, adenoviruses usually cause infections in scattered occurrence, rather than in clusters.
2. In 2007, a cluster of new military recruits had an acute respiratory illness during their training at the Texas Air Force Base. Some of these recruits were severely ill and had to be hospitalized, while most of the recruits had mild to moderate symptoms.
3. In Ireland, the Ad14 was confirmed in nine cases in 2009 and 2010.
[메디컬리포트=Ralph Chen 기자]