Powassan Virus in Children: Rapid Transmission and Encephalitis
Powassan virus in children is rarely reported but can be severe.
Two infants developed Powassan virus encephalitis after brief tick attachment.
The cases highlight the importance of preventing ticks from being carried into the home.
Powassan virus in children is not commonly reported. In this article, Feder and colleagues describe two infants with tick bites who developed Powassan virus encephalitis. [1]
The case report demonstrates that rapid transmission of Powassan virus (POWV) can occur and highlights the importance of prevention measures for parents and caregivers.
In both cases, adults unknowingly exposed the children to ticks infected with Powassan virus.
Powassan Virus Encephalitis in Two Children
A 5-month-old infant was hospitalized after experiencing fevers for two days, along with vomiting and facial twitching that progressed to seizures.
Two weeks before symptom onset, a tick had been removed from the infant’s forehead. Testing for Powassan virus was positive. [1]
The second case involved a 2-month-old infant who presented with fever and listlessness for one day.
“He then developed left sided focal seizures (rhythmic left arm twitching, facial deviation to the left, and tongue thrusting with lip smacking),” the authors wrote. [1]
A tick had been removed from the infant’s arm approximately two weeks before hospitalization. The parents believed either the father or family dog had brought the tick into the home after outdoor activity.
The tick reportedly was not engorged and had not fed for more than 24 hours. [1]
READ MORE: No neurologic damage in 3 children with Lyme disease and Powassan virus
“POWV infection was confirmed by a positive PRNT on both serum and CSF,” the authors explained. [1]
Powassan Virus May Lead to Long-Term Neurologic Problems
“POWV infection of humans has been notable for the severity of both the acute disease and the long-term sequelae,” the authors noted. [1]
Chronic neurologic complications reportedly occur in approximately 50% of patients and may include:
- Hemiplegia (paralysis on one side of the body)
- Muscle wasting
- Personality changes
- Headaches
Adults May Unknowingly Expose Children to Infected Ticks
“The circumstances under which the 2 children reported here acquired infection require some comments that are pertinent to prevention of future cases,” the authors wrote. [1]
Infants are generally not expected to encounter tick exposure independently. In both cases, adults likely carried ticks into the home after outdoor activities.
Feder pointed out that “in both of our cases, parents presumably brought ticks into their homes after outdoor activities.” [1]
[bctt tweet=”Powassan virus transmitted rapidly to two young children. Case report highlights need for preventative tick bite measures by parents/caregivers.” username=”DrDanielCameron”]
In the first case, the father had been walking in wooded areas and brushed multiple ticks off his clothing outside before returning home.
In the second case, the family believed the father or dog brought the tick indoors after a walk.
Dogs may carry infected ticks indoors even when they do not appear ill themselves.
Tick Bite Prevention for Parents and Caregivers
Parents and caregivers should be educated about several prevention strategies:
- Outdoor clothing may temporarily block ticks from attaching to skin, but ticks may later detach from clothing indoors when body heat decreases.
- Parents should check for ticks more than once because ticks may crawl before attaching.
- Outdoor clothing may be treated with permethrin, which can kill ticks after contact.
- Dogs may carry ticks indoors and should be inspected after outdoor exposure.
- Some tick prevention products for dogs only work after a tick attaches, although permethrin-containing collars may help repel ticks before attachment.
Clinical Perspective
These pediatric Powassan virus cases highlight how rapidly transmission may occur, even after brief tick attachment.
The report also underscores the importance of household prevention strategies, particularly when adults or pets may unknowingly bring ticks indoors.
Although the authors did not discuss treatment details, both infants reportedly recovered. [1]
Frequently Asked Questions
Can Powassan virus affect children?
Yes. Although uncommon, Powassan virus infection in children can lead to encephalitis and seizures. [1]
How quickly can Powassan virus spread after a tick bite?
The case report suggests transmission may occur rapidly, even when the tick was attached for less than 24 hours. [1]
Can dogs bring infected ticks into the home?
Yes. The authors noted that dogs may unknowingly carry infected ticks indoors after outdoor exposure. [1]
Related Articles:
Podcast: 6-week-old boy with Babesia
Podcast: 5-week-old girl with Lyme disease
Case report: Fatal Powassan virus infection: a.k.a deer tick virus
References:
- Feder HM, Telford S, Goethert HK, Wormser GP. Powassan Virus Encephalitis Following Brief Attachment of Connecticut Deer Ticks. Clin Infect Dis. 2020.
Dr. Daniel Cameron, MD, MPH
Lyme disease clinician with over 30 years of experience and past president of ILADS.
Symptoms • Testing • Coinfections • Recovery • Pediatric • Prevention
I would like to see follow up for families to better understand what outcomes can occur for children.
My grandson is the first case discussed in this article. He is now 6 years old and there is no guidance for possible complications, though there are some that were not discovered until recently.
Thanks for reminding us of the need for further research.
Thanks for sharing. I have not seen information on possible complications. I am concerned that any subsequent symptoms may be related to a treatable tick borne illness.