Wednesday, August 31, 2016

Taiwan CDC: 1st Case Of EV-D68 With Acute Flaccid Paralysis

CDC EV-D68 Fact Sheet


In August of 2014, a seldom seen non-polio enterovirus D-68 (EV-D68) appeared in America’s Midwest and quickly spread across the nation, causing a wide spectrum of respiratory illness, predominantly in young children and adolescents (see Kansas City Outbreak Identified As HEV 68).

At roughly the same time, doctors reported a coincident rise in cases of neurological illness with AFP (acute flaccid paralysis) or limb weakness – often associated with a recent respiratory illness –  across the country.

The link between EV-D68 infection and AFP - while not conclusively proven - has grown stronger over the past two years due to increased research, including a recent EID Journal analysis (see Enterovirus D68 Infection in Children with Acute Flaccid Myelitis, Colorado, USA, 2014) which found:

In conclusion, we found an epidemiologic association between AFM and EV-D68 infection among children with respiratory illness during 2014 in Colorado. This finding goes beyond previously reported temporal associations between AFM clusters with increases in hospital admissions for respiratory symptoms and detection of EV-D68 in AFM case-patients. These epidemiologic data, combined with the biological plausibility of this association, suggest a possible causal link; however, a gap remains between the epidemiologic data and the data from extensive testing of laboratory specimens.
First isolated in California in 1962, EV 68 (genus Enterovirus - family Picornaviridae – species HEV-D) had only rarely been reported up until the mid-2000s.  In 2011, however  – in MMWR: Clusters Of HEV68 Respiratory Infections 2008-2010 – we looked at a half dozen HV 68 associated clusters which occurred in Asia, Europe, and the United States during 2008--2010.

The 2014 EV-D68 epidemic eventually ran its course, and while a few cases were reported in Europe, the outbreak was mainly confined to North America. In the end, more than 100 kids and young adults experienced neurological symptoms linked to the infection.

While we've heard very little about EV-D68 since then, other enteroviruses - particularly EV-71 (see ECDC: RRA On Recent Enterovirus Outbreaks In Europe) - continue to spark serious outbreaks around the globe. 

EV-D68 has since been recognized as an important emerging pathogen (see Global reemergence of enterovirus D68 as an important pathogen for acute respiratory infections) and many countries - including Taiwan - are now actively testing for it.

All of which brings us to a  report from Taiwan's CDC on their first case of AFD linked to an EV-D68 infection. While they've reported a handful (n=32) of sporadic, mild cases over the past 2 years, this is their first serious infection since surveillance began. 

As Taiwan CDC identifies first case of AFP tested positive for EVD68, public urged to heighten vigilance, wash hands with soap correctly and frequently, rest at home when sick ( 2016-08-30 )
The Taiwan Centers for Disease Control (Taiwan CDC) has recently received a report of acute flaccid paralysis (AFP) in a patient that has been tested positive for enterovirus D68 (EVD68).In addition, the gene sequence of the virus strain detected in the case is similar to the virus strain identified in the United States. This is also the first AFP case associated with EVD68 since the implementation of active surveillance of AFP cases in Taiwan.

The case is a 5-year-old boy who resides in Taipei City and has no recent travel history. On August 14, 2016, he sought medical attention at a clinic after developing weakness in his left arm. When his symptom persisted, on August 17, he sought further medical attention at a hospital, and was hospitalized for treatment and reported to the health authority. 

The case was confirmed to be an AFP case by the AFP surveillance investigation expert. His specimen was tested positive for EVD68 by the Taiwan CDC laboratory and identified as the same virus strain detected in the U.S. The investigation also revealed that none of the family members residing in the same household with the case and the close contacts at school had recently visited U.S. or developed symptoms. As of now, the case’s symptoms have abated, but the case is still hospitalized for observation. 

Taiwan CDC will continue to monitor and follow up on the case for at least 60 days after the paralysis onset and will consult with neurologists to confirm whether the cause of AFP in the case is due to EVD68 infection.

Besides collecting stool specimen, all AFP cases are required to submit additional oropharyngeal specimen for screening EVD68 in Taiwan since mid-June 2015 in order to better understand EVD68 activity in Taiwan and the pathogenesis. The case was the first AFP case tested positive for EVD68 in Taiwan. 
Since EVD68 was included in the community-based enterovirus surveillance in July 2014, 8 specimens (positive rate: 0.27%) and 16 specimens (positive rate: 0.56%) were respectively tested positive for the virus in 2014 and 2015. Thus far this year, as of Week 32, a total of 8 specimens have been tested positive for EVD68 (positive rate: 0.28%). The 32 specimens tested positive for EVD68 over the recent 3 years are all mild cases of respiratory symptoms without paralysis. Of these cases, 19 are males and 13 are females. Their ages range between 0 and 49. Children aged below 5 account for 59.4% of the 32 cases.

EVD68 is transmitted through the same route as other enteroviruses. Taiwan CDC reminds the public to practice good personal hygiene both at home and when outside and wash hands frequently with soap and water. In addition, it is important to lather hands with soap and scrub for at least 20 seconds in order to effectively prevent enterovirus infection. Infants and children are at an increased risk for severe enterovirus infection. When a child is diagnosed with enterovirus infection, parents and child caregivers are urged to refrain the sick child from close contact with other children to prevent further spread of the disease. For more information, please visit the Taiwan CDC website at or call the toll-free Communicable Disease Reporting and Consultation Hotline, 1922 (or 0800-001922).

One case does not an outbreak make, and this may simply turn out to be a one-off event, but the 2014 North American outbreak is a reminder that this virus has the ability to spread quickly - particularly in school environments - and so we'll keep an eye on this.

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