Season flu vaccinations are low-cost and readily available, but many still choose to forgo them. Now, a new study gives us another reason to go out and get the shot: flu virus infection may increase your risk of developing Parkinson’s disease. Although the reason isn't clear, the finding highlights that some of the risk factors of this degenerative disease may be environmental.

According to the research, in a lab setting, the toxins involved with the flu virus triggered Parkinson's disease, and the team believe the same could also happen in a real-life setting. The report was published in npj Parkinson's Disease.

Read: Parkinson’s Disease Treatment Reverses Symptoms In Mice, Increases Dopamine Receptors

"The H1N1 virus that we studied belongs to the family of Type A influenzas, which we are exposed to on a yearly basis," says study researcher Dr. Richard J. Smeyne in a recent statement. "Although the work presented here has yet to be replicated in humans, we believe it provides good reason to investigate this relationship further in light of the simple and potentially powerful impact that seasonal flu vaccination could have on long-term brain health."

For the study, the team exposed mice to a specific strain of the influenza virus, H1N1, also known as swine flu. The team observed that the infection caused inflammation in the brain of the animals via an inflammatory chemical that was released by the immune cells involved in fighting the infection. In addition, even long after initial H1N1 infection, mice who had been infected with this flu virus were still more likely to develop Parkinson’s disease, and developed a more severe form of the illness.

According to the Mayo Clinic, Parkinson’s disease is a progressive disorder of the nervous system that causes an individual to slowly lose motor function. In the early stages, the disease may be characterized by little more than a slight tremor, but then as time goes on it can progress to disrupt movement, walking, and even speech. The condition cannot be cured at the moment, but there are a number of medications and treatments that can improve symptoms and slow down disease progression.

The disease is associated with low dopamine levels, a type of hormone found in the brain, Medical News Today reported. It's still unclear what causes these levels to drop, leading individuals to eventually develop the disease, although certain behaviors such as having more disrupted sleep patterns are known to increase one's risk. In addition, injury to the brain that does not heal correctly, such as traumatic head injury, is also linked to increased Parkinson’s risk.

Source: Sadasivan S, Sharp B, Shultz-Cherry S, Smeyne RJ. Synergistic effects of influenza and 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP) can be eliminated by the use of influenza therapeutics: experimental evidence for the multi-hit hypothesis. Npj Parkinson’s Disease . 2017

See Also:

What Causes Parkinson’s Disease? After 20 Years Of Research, Scientists Find Third Gene Linked To Neurodegenerative Disease

Parkinson's Disease Vs. Essential Tremor Early Symptoms, How They Differ