The flu isn't the only virus that could leave you feeling feverish and generally miserable this winter — another virus, called adenovirus, can cause similar symptoms, although doctors don't routinely test for it.
Adenoviruses are prolific viruses that can cause a variety of illnesses, including upper respiratory infections — such as colds — as well as pneumonia, gastrointestinal illness, conjunctivitis (pink eye) and even urinary tract infections, said Dr. Amesh Adalja, a senior scholar at the Johns Hopkins Center for Health Security. (There are 52 strains of adenovirus, and different strains cause different illnesses.)
When a person has a respiratory infection caused by an adenovirus, "it would be really hard to tell it apart from influenza" just by looking at the patient, Adalja said. Symptoms can include fever, sore throat, cough and runny nose, according to the Centers for Disease Control and Prevention (CDC). [The 9 Deadliest Viruses on Earth]
However, unlike the flu, adenovirus doesn't have a "striking seasonality," Adalja told Live Science. Although outbreaks of adenovirus infections are most common in the late winter, spring and early summer, they can occur year-round, the CDC said.
In some cases, adenoviruses can cause severe respiratory symptoms, including pneumonia, particularly in patients whose immune systems are compromised, Adalja said. In 2007, an outbreak of adenovirus sickened about 140 people in four states, killing 10 patients, according to the CDC. But that fatality rate doesn't compare to that of the flu, which can cause between 12,000 and 56,000 deaths per year, according to the CDC.
Outbreaks of adenovirus in the military led the U.S. Department of Defense to begin vaccinating military recruits against two strains of the virus in 1971, according to Medscape. When vaccine production stopped in 1996, cases of adenovirus in the military increased, as the disease spreads easily in close quarters. This re-emergence of the disease led to the reintroduction of the vaccine among recruits in 2011, Medscape reported. It's estimated that the vaccine prevents about 15,000 cases of adenovirus infections in U.S. military recruits, according to the U.S. Army Medical Material Development Activity.
A recent study, published in the journal Emerging Infectious Diseases, looked at adenovirus respiratory infections in nonmilitary members and concluded that the vaccine should also be considered for susceptible groups outside the military, such as those living in long-term-care facilities or college dorms.
Adalja agreed that "because [adenovirus] does cause a considerable burden of illness, we want to explore" the ability to use the vaccine outside of the military context.
For example, the vaccine may benefit people at high risk of contracting the virus, such as patients with lung disease and others with compromised immune systems, but it may even benefit the general population, Adalja said. However, future studies would be needed to examine which segments of the population would benefit most, and whether vaccination would be cost-effective, he said.
Original article on Live Science.