What students should know about the H3N2 flu

U.Va. health officials and immunologists discuss H3N2 flu, student wellbeing

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In January of last year, the SDAC debuted an online system, featuring letter notifications automatically sent to professors detailing the accommodations required for a student.

Sarah Lindamood | Cavalier Daily

A harsh subtype of the influenza — H3N2 — has been associated with 53 pediatric deaths this season and has even pushed one state to declare a public health emergency. As the weekly flu update from the Centers for Disease Control and Prevention predicted that flu activity will continue to remain high, Elson Student Health Center directors described how students can protect themselves amid the outbreak.

Jessica Simmons, associate director of General Medicine at Student Health, explained that some students are unable to differentiate between the signs of the flu and those of an upper respiratory infection, or the common cold. Both the flu and the common cold share symptoms like congestion, a persistent cough and runny nose. However, unlike the common cold, the flu is accompanied by a fever and severe body aches. 

“A lot of times, the flu will hit very suddenly, so you’ll be feeling well and go to class without any problem,” Simmons said. “Then in the afternoon you’ll start to feel a little bit achy and by that evening, you’ll have a fever and the respiratory symptoms will start.” 

The onset of a fever makes students highly contagious. Jamie Leonard, director of the Office of Health Promotion at Student Health, said in an email that students should not attend class, go to work or participate in clubs until they have been fever-free without medication for 24 hours. Instead, students should rest and maintain a high fluid intake, taking ibuprofen or Tylenol as directed for fever and body aches.

Simmons strongly encourages students to call Student Health and ask to speak with a triage nurse. The triage nurse will schedule a clinic appointment, suggest procedures for supportive care and prescribe Tamiflu, an antiviral drug, if necessary. 

“For Tamiflu to be effective, a patient should be seen and treated within the first 48 hours of illness,” Leonard said. “Tamiflu decreases duration of flu symptoms by about a day.” 

Physicians may diagnose sick students who are generally healthy with the flu clinically, based on present symptoms and without the formal flu test — in which nasal mucus samples are collected with a Q-tip for a polymerase chain reaction test to detect viral genetic material. But despite this highly accurate test and the diverse treatment options available, Simmons and Asst. Biology Prof. David Kittlesen agreed that prevention is more valuable than a cure in the context of the flu.

In addition to keeping a healthy diet, exercise and sleep schedule, Leonard and Simmons urged students to frequently wash their hands with soap and warm water and avoid interacting with others who are sick. Students who are in high-density environments can help prevent the spread of the flu by covering coughs and sneezes, avoiding touching their eyes, nose and mouth and refraining from sharing utensils and drinks.  

The flu vaccine — a killed virus that cannot give people the flu — is another important preventative measure, said Simmons and Kittlesen. Once a flu shot has been administered, it takes about two weeks for it to be effective. During this time, the body has no protection against the flu. Even though some studies have projected the flu vaccine to be less than 20 percent effective this year, Simmons noted that contracting the flu without being vaccinated is the worst-case possibility. 

“[The vaccine] gives you some level of protection, so something is better than nothing,” Simmons said. “If you get a trivalent flu shot or a quadrivalent flu shot, it will protect you against three of four different types of flu.”

Following these preventative guidelines may be especially valuable given the relative severity of the flu in the past five years at the University.

“So far this academic year, we are at levels higher than two other years and about to surpass a third,” Simmons said. “And experts speculate we are about halfway through the flu season.”

Kittlesen explained that a mix of factors contribute to H3N2’s fatality. A non-living pathogen or disease-causing agent, such as influenza, is more likely to be successful if it does not kill its host right away — a live host will help the virus spread more rapidly. 

Furthermore, influenza is an RNA virus, meaning that its genome is replicated by enzymes called RNA polymerases. RNA polymerases’ lack of proofreading mechanisms enable the virus to mutate more extensively. This high rate of mutation may explain the low efficacy of the flu vaccine, since a mutant strain of H3N2 may evade the body’s immune system that could be more accustomed to detect to an older, “outdated” —  or unmutated — strain of virus in the vaccine. 

It is also not entirely a coincidence that peak flu activity occurs during the colder months of winter.

“The traditional view is that congregating in winter to stay warm helps the virus spread faster,” Kittlesen said. “But there is also evidence that the virus is more stable in the cold and that because humidity is lower in the winter — meaning the air is dryer — the virus stays aerosolized longer.” 

The letters “H” and “N” in H3N2 refer to components of the virus — hemagglutinin, a glycoprotein that helps the virus adhere to host cells, and neuraminidase, an enzyme that enables replicated viral molecules to exit host cells, respectively. Current vaccines for the flu focus on presenting hemagglutinin and neuraminidase as targets for the body’s immune system. 

Frederick Hayden, professor emeritus at the School of Medicine, said research is starting to favor how the immune system can detect other parts of the virus — such as reserved epitopes, sites on the virus that antibodies detect that do not change as frequently with evolutionary selection. Combination therapies consisting of a cocktail of different drugs are also becoming popular.

“The hope is that if polymerase inhibitors that target different parts of the virus reproductive scheme are used together with current agents, they’ll produce greater protection against the flu,” Hayden said.

There are also efforts towards developing a universal vaccine that may eradicate the need to be immunized annually against the flu. Student Health also noted that future additions to the University may better help to provide for students.

“We are space limited currently and are thankful to the Board of Visitors and the administration for their support and planned construction of a new Student Health & Wellness Building so we can fully support our over 22,000 students during such outbreaks,” Simmons said.

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