Can You Explain the Differential Diagnosis for Powassan virus?
For all patients who live in areas where the Ixodes scapularis
tick is present, it’s important to consider things like Lyme, Anaplasma
, Babesia, Ehrlichia
, as well as some of the other Borrelia
In a patient who is presenting with neurologic symptoms or encephalitis, that differential diagnosis can be a lot broader. So, that can include things like West Nile virus, which is commonly found in areas that are endemic for Powassan [virus] and for Lyme disease.
What Can You Tell Us About the Treatment Options Available for Powassan virus?
Currently, the treatment [for Powassan virus] is largely supportive. Very little is known about the virus because we don’t have a lot of data in humans, so there’s no specific treatment that we can recommend.
In general, for supportive care, we recommend fluids, if needed, [and] providing basic care for encephalitis, [which] can include ICU care, neuro-rehabilitation after the infection. We recommend treating this like you would any other patient with encephalitis, or possibly as you would a patient who has West Nile encephalitis, because we don’t know what the best course of treatment is.
Should There Be Routine Testing for Powassan virus?
At this point we wouldn’t recommend testing patients routinely for Powassan virus because we don’t know what clinical benefit that would have or how it would alter treatment. If you do have a patient [who’s] critically ill or a patient [who] has encephalitis and you live in an area endemic for Lyme, those patients should be tested for Powassan virus.
Is the Prevalence of Powassan Virus Increasing in Humans?
Powassan [virus] is an emerging infection, and so, we know that the amount of Powassan that we’re been seeing in ticks has been increasing, and the seroprevalence in mammals has been increasing. [As a result], it’s likely that we’re going to see more of this as time progresses. I think we need to do further studies looking at what the true clinical presentation of Powassan virus is. We know very little aside from patients who have neurologic disease, because that’s the population we’ve really tested before. We also need to learn more about how patients [who] have coinfection with other tick-borne diseases, such as patients [who] have both Lyme disease and Powassan at the same time present, and if they have a higher severity of illness, or if their illness lasts for a longer period of time.