EMERGING ENTEROVIRUSES: ANYTHING TO WORRY ABOUT?
Thea Kølsen Fischer Professor, MD, DMSc Virology Surveillance and Research Statens Serum Institute Copenhagen, Denmark
ECCMID VIENNA APRIL 2017 ESCMID Online Lecture Library © by author CONTENT
• General aspects of enteroviruses • Severe emerging enteroviruses (focus: EV-D68, EV-A71) • recent outbreaks • clinical presentation • estimated disease burden • diagnostic challenges • surveillance • Impact on global health • Future challenges ESCMID Online Lecture Library © by author VIRUS CLASSIFICATION 1. Aphthovirus PICORNAVIRIDAE FAMILY 2. Aquamavirus 3. Avihepatovirus 4. Avisivirus 5. Cardiovirus 6. Cosavirus 7. Dicipivirus 8. Enterovirus 50 species divided 9. Erbovirus 10. Gallivirus among 29 genera 11. Hepatovirus 12. Hunnivirus 13. Kobuvirus 14. Kunsagivirus 15. Megrivirus 16. Mischivirus 17. Mosavirus 18. Oscivirus 19. Parechovirus 20. Pasivirus 21. Passerivirus 22. Rosavirus 23. Sakobuvirus 24. Salivirus 25. Sapelovirus 26. Senecavirus 27. Sicinivirus 28. Teschovirus Chris Lauber, and Alexander E. Gorbalenya J. Virol. 2012;86:3905-3915 29. TremovirusESCMID Online Lecture Library © by author ENTEROVIRUS: 12 SPECIES
Current species name* Former species name 1 Enterovirus A Human enterovirus A 2 Enterovirus B Human enterovirus B 3 Enterovirus C Human enterovirus C 4 Enterovirus D Human enterovirus D 5 Enterovirus E Bovine enterovirus (group A) 6 Enterovirus F Bovine enterovirus (group B) 7 Enterovirus G Porcine enterovirus B 8 Enterovirus H Simian enterovirus A 9 Enterovirus J unclassified simian viruses 10 Rhinovirus A Human rhinovirus A 11 Rhinovirus B Human rhinovirus B 12 Rhinovirus C Human rhinovirus C ESCMIDRef: http://www.picornaviridae.com/enterovirus/enterovirus.htm Online Lecture Library © by author ENTEROVIRUSES (EV)
>100 serotypes belong to species A-D
ESCMID OnlineNathan LectureL. Yozwiak et al. J. Virol. 2010;84:9047 Library-9058 © by author STRUCTURE & PHYSICOCHEMICAL PROPERTIES
Resistant to: • Gastric acid (except EV-D68) • Freezing • Common disinfectants: • 70% ethanol, isopropanol, Lysol, or quaternary ammonium compounds. • Organic solvents: • ether and chloroform, Inactivated by: • temperatures > 56°C • chlorination • formaldehyde Ref: Solomon T, Lewthwaite P, Perera D et al. Virology, epidemiology, pathogenesis, and control of enterovirus 71. Lancet. Volume 10, Issue 11, • ultraviolet irradiation 2010, 778–790 • strong acids • free residual chlorine EV ESCMID Online Lecture Library © by author OPEN READING FRAME EV diagnostics and typing (Alex) STRUCTURAL PROTEINS NON-STRUCTURAL PROTEINS
nt 2602-2977
nt 972-1536
Viruses of different genotypes have < 75% nucleotide identity, and < 85% amino acid identity.
Ref: Piralla et al PLOS One 2013, Hober D, Sané F, Riedweg K et al. (2013). Viruses and Type 1 Diabetes:, ISBN:ESCMID 978-953-51-1017-0, InTech ,Online DOI: 10.5772/52087 Lecture Library © by author REPLICATION & TRANSMISSION
Transmission: • Fecal-oral and respiratory secretions
Replication: • Upper respiratory tract/tonsils • Intestinal tract/lymphoid tissue • Shedding: 2-4 weeks (up to 11 weeks)
Ref: httpESCMID://www.microbiologybook.org/virol/entero Online -path.jpgLecture Library © by author ENTEROVIRUS DIAGNOSIS
SPECIMENS DIAGNOSIS
• Respiratory secretions (saliva, • RT-PCR sputum, nasal mucus) • Cultivation • Stool • Blood • Spinal fluid • Urine • Vesicle fluid • Autopsies from internal organs (e.g. lungs, liver, intestine, heart and brain) ESCMID Online Lecture Library © by author CLINICAL MANIFESTATIONS encephalitis/meningitis EV-A71, Echovirus, Coxsackie A & B paralysis me haemorrhagic conjunctivitis Poliovirus (1-3), EV-D68, EV-A71 paralysis hitis Coxsackievirus 24, EV 70
common cold ENTERO c diarrhea Rhinoviruses VIRUS many EVs
hand, foot & mouth dis. Hase pha Pharyngitis/herp angina Coxsackievirus A, EV-A71 Coxackievirus myoca
myocarditis ESCMID OnlineEchovirus, Coxsackievirus LectureA & B Library © by author ZOOMING IN ON EMERGING EV’S
ESCMID Online Lecture Library © by author EV A-71 (EV 71) EPIDEMICS • 1969 (California, USA): • Isolated from 20 cases with CNS disease. • Sporadic outbreaks of HFMD • 1975 Bulgaria (n~700) • 1978 Hungary‘‘EVA(n~1550)-71: Polio of the 21st century.’’ • 2007 Netherlands (n~57) • 2014 Denmark (n~34) • 2016 Spain (n>100) • 1990’s-2015 (Asia-Pacific region): • Major outbreaks of HFM and/or CNS disease ESCMID Online Lecture Library © by author EV-A71 SERO-EPIDEMIOLOGICAL STUDIES
Singapore Taiwan Longitudinal sero-surveys (China): A populations Cord blood 44% maternal Abs - 1 month old 0% maternal Abs - seroconversion rate 1-6 months - 38-44% fluctuates over time, 12-23 months old <1% 0-15% leaving some children’s 24 months 12% - cohorts susceptible to 36 months 24% -
EV-A71 infection 60 months 48% 50%
Ref: WHO: A Guide to Clinical Management and Public Health Response for Hand, Foot and MouthESCMID Disease (HFMD) 2011. Online Lecture Library © by author 4 CLINICAL STAGES OF EV-A71 INFECTION
HALLMARK OF ASIAN EV71 CNS INFECTION: HFMD (MOST CASES CBRAINSTEM ENCEPHALITIS RESOLVE ) + PULMONARY OEDEMA
After prodromal HFMD and 3-5 days of CNS INVOLVEMENT feber: 1. deterioration with acute and CARDIORESPIRATORY FAILURE (FEW SURVIVE) progressing cardiorespiratory failure 2. pulmonary oedema/haemorrahges CONVALESCENCE + shock 3. death < 24 hours Ref: OoiESCMIDMH, Wong SC, Lewthwaite P et al. LancetOnline 2010. (9) p 10971105 Lecture Library © by author STAGE 1: EV-A71 MUCOCUTANEOUS AND RESPIRATORY MANIFESTATIONS
• Mild febrile illness • Papulovesicular rash (HFM) in children >2 years • Widespread, atypical rashes < 2 years • Upper respiratory tract infection • Gastroenteritis • Non-specific rashes • Exacerbation of chronic lung disease
Ref: Ooi MH, Wong SC, Lewthwaite P et al. Clinical features, diagnosis, and management of enterovirus 71. ESCMIDLancet. null, Volume 9, Issue 11 , 2010Online, 1097–1105 Lecture Library © by author STAGE 2: EV-A71 CNS-INVOLVEMENT
Typical presentation: Milder forms: Brain-stem encephalitis with or without myelitis (NB. myeclonic jerks an early sign of brainstem involvement) Myelitis (acute flaccid paralysis) Milder cases of brainstemencephalitis may be associated with drowsiness, myoclonusand/or tremors. Ataxia is mild and transient Moderate forms: Weakness Bulbar involvement (dysarthria, dysphagia, hypopnoea) and(or involvement of other cranial nerves(VI, VII) ESCMID Online Lecture Library © by author STAGE 2: EV-A71 CNS-INVOLVEMENT
Meningitis/enchephalitis
MRI: Child 10 months Presented 3 months earlier with: • Somnolence, tachycardia, coma • Recovered consciousness - remained dependant on ventilator
Ref: W-C Shen, H-H Chiu, K-C Chow, et al. MR imaging findings of enteroviral encephalomyelitis: an outbreak in Taiwan. Am J NeuroradiolESCMID, 20 (1999), pp. 1889–1895 Online Lecture Library © by author STAGE 3: EV-A71 CARDIORESPIRATORY FAILURE
Acute haemorrhagic pulmonary oedema of neurologic origin and/or myocarditis.
Symptoms: • Cough and hemoptysis, • Cyanosis When clinically evident, condition is usually very severe. Low survival rate ESCMID Online Lecture Library © by author EV-A71 CASE-FATALITY RATES
ASIA (1998-2012)
OUTBREAKS
Spain (2016)
ESCMID Online Lecture Library © by author EV-A71: MOLECULAR EPIDEMIOLOGY BY GLOBAL REGIONS
TAKE HOME MESSAGES:
No particular genotype associated with increased risk of acute neurological disease
Largest outbreaks with EV-A71 C4 in China (2008-2011, n>1 mio, ~2500 deaths) and C4 in Vietnam (2011)
Recombination events likely main driver in evolution of new genetic lineages ESCMID Online Lecture Library © by author EV-A71 OUTBREAK SPAIN 2016
• N > 100 cases of EV-A71 encephalitis • Case definition: EV-RNA detection and positive findings in neuroimaging (likely that the actual number of cases is underestimated) • Age range: 3 months – 10 years (57% between 1-2 years) • Gender distribution: 58% males • Main symptoms: seizures, drowsiness and myoclonia • 45 cases of rhombencephalitis treated between March and July 2016, - all had complete or nearly full recovery • 4 cases with acute flaccid paralysis - 2 suffer from monoparesis • 1 case with fulminant brainstem failure and heart abnormalities ESCMIDsuffers from severe sequelae. Online Lecture Library • 1 died in September 2016 © by author EV-D68 FROM NOWHERE TO ANYWHERE, (OR?)
ESCMID Online Lecture Library © by author EV-D68: HISTORY & CLINICAL PRESENTATION
First identified in 1962
Known to cause respiratory illness
Known to infect children and adults
Similar to rhinoviruses
Clusters have previously been described in the US, Europe, and Asia ESCMID Ref.Online Hansen C, Midgley S andLecture Fischer TK. Lancet Inf Dis 2016 Library © by author EV-D68 PREVALENCE BEFORE 2000 (RED) AND AFTER 2000 (BLUE)
2005 to 2010 reports from USA, France, Netherlands, UK; Red before 2000 Philippines, and Japan Blue after 2000 ESCMID1962-2013 Online Lecture Library © by author EV-D68 OUTBREAK 2014
Europa: 93 cases, British Columbia: 3 AFP 221 cases Canada: Min. 214
USA: Kina: 1,153 cases 1 case 107 med AFP
Chile: 2 cases Total cases EV D-68 (n) =1684 AFP (n) = 110 (6.5%) Deaths (n) =17 ESCMID Online Lecture Library © by author EV-D68 UNDERDIAGNOSED & UNDERREPORTED – WHY?
ESCMID Online Lecture Library © by author EV-D68: A DIAGNOSTIC CHALLENGING VIRUS
Specimen: • Respiratory (nasopharyngeal and oropharyngeal swabs preferred) • or any other type of upper respiratory specimen and/or sera tests: Tests: Realtime RT-PCR targeting the 5’un-translated region for detection of HRV and EV 1 Specific EV-D68 real-time RT-PCR assay2 Partial sequencing of VP1 of either EV-D68 positive or EV/RV positive samples or the partial viral protein (VP)4–VP2 sequences NB. Consider EV-D68 testing of specimens that test positive for enterovirus or rhinovirus (not all rhinovirus PCRs pick up EV-D68)
(1: Nix etESCMID al. J Clin Microb. 2006. 2. Poelman Online R et al. R. J. Clin . LectureVirol. 2015) Library © by author EV-D68 OUTBREAK NORTH-AMERICA 2014
ESCMID Online Lecture Library © by author RHOMBENCEPHALITIS CAUSED BY EV-D68
Red arrows point at dorsal involvement at the level of the pontine (A) and bulbar tegmentum (B) as well as the entire medulla
☆
Ref. Macaya A , Felipe-Rucián A. Enterovirus and neurological complications. Anales de Pediatría (English Edition), Volume 86, IssueESCMID 3, 2017, 107–109 Online Lecture Library © by author HAS EV-D68 DISAPPEARED? NO
2016:
Outbreak of EV-D68 in France with serious neurological complications
EV-D68 cases/clusters in Wales and Netherlands
33 AFM/AFP EV-D68 cases reported in Wales, Ireland, Italy, Denmark, Germany, Norway, Austria, Scotland, Spain, Sweden, the Netherlands
In US, 39 cases of AFM (CDC case definition), with 23% positive for EV-D68 I see no problem…………
CourtesyESCMIDof Prof. B Niesters, Groeningen Online Lecture Library © by author ESCMID Online Lecture Library © by author EV-C105
• Detected: 2010 Peru & Congo • Diagnostic challenges: Diverging in the 5 UTR from other EV group Cs Clinical disease: poorly understood (respiratory disease but recent reports on flaccid paralysis
ESCMID Online Lecture Library © by author EV-C105 CASE: DURING EV-D68 OUTBREAK
• 6 year old girl, previously healthy • Ill with cough and rhinorrhea • 10 days later fever , headache, ear pain and right axilla for 24 hours • 14 days later: acute onset of progressive right upper extremity weakness • Physical examination: right upper extremity weakness; absent right biceps, triceps, and brachioradialis deep tendon reflexes; and a diminished right ESCMIDpatellar reflex. Online Lecture Library © by author ESCMID Online Lecture Library © by author SUMMARY
• EV-A71. Profile change in Asia-Pacific region over the past 2 decades: from rare and sporadic cases of HFMD to regular and large epidemics • EV-A71 profile in Europe also undergoing changes (virus molecular evolution & importation of new virus strains from outside the EU). • EV-D68. Profile change in North America and Europe: From sporadic rare cases to major outbreak of severe respiratory and neurologic disease • EV-C105 (&EV-C109). Sporadic since discovery in 2010: Respiratory and few AFP cases • Diagnostic challenges for EV-D68 and EV-C105. Burden and consequences not well described • No effective antiviral cure available • New Asian-produced EV-A71 vaccine candidates in pipeline • Strengthening EV surveillance in general and EV-A71 in particular prior to vaccine introduction ESCMID Online Lecture Library © by author PERSPECTIVES: TO BE CONTINUED………..
ESCMID Online Lecture Library © by author TO CONSIDER:
When you look at the relationship between bugs and humans, the more important thing to look at is the bug. When an EV like polio goes through the human gastrointestinal tract in three days, its genome mutates about two percent. That level of mutation—two percent of the genome—has taken the human species eight million years to accomplish. So who’s going to adapt to whom?
Citat: David Morens, NIH EV ESCMID Online Lecture Library © by author THANK YOU FOR YOUR ATTENTION
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