Emergence du Chikungunya dans les Antilles et caractéristiques virologiques de l épidémie

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Peter Davidson
5 years ago
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Gallian P, Prat CM, Cassadou S, Flusin O, Huc-Anais P, De

1 Emergence du Chikungunya dans les Antilles et caractéristiques virologiques de l épidémie Maquart M, Gallian P, Prat CM, Cassadou S, Flusin O, Huc-Anais P, De Lamballerie X, Leparc- Goffart I Kick-off Meeting REACTing I. Leparc-Goffart N 1

severe arthralgia after a «dengue-like» fever episode

2 Emergence du Chikungunya aux Amériques 18th November 2013: 5 patients without any travel history presenting severe arthralgia after a «dengue-like» fever episode Saint Martin Kick-off Meeting REACTing I. Leparc-Goffart N 2

3 Alert 18/11/2013: Alert by clinician to public health services 5 suspected cases 22/11/2013: Epidemiological and entomological investigation 8 suspected cases 05/12/2013: 1 st positive CHIKV RT- PCR. CHIKV emergence is confirmed 02/12/2013: Analysis at the French NRC: serology and RT-PCR Detection of recent alphavirus infection by serology 10/12/2013: NGS sequencing: the virus belongs to the Asian genotype, and not ECSA. Strain and sequence available on EVA European Virus Archive Evaluation of published RT-PCR diagnostic systems N 3

4 Phylogeny of CHIKV Saint Martin Leparc-Goffart et al, 2014 The Lancet N 4

5 What did we learn from this epidemic? Is a case definition useful with Dengue and Chikungunya co circulation? Kinetic of infection in human with Chikungunya Asian lineage? Blood donors study: dynamics of the outbreak Kick-off Meeting REACTing I. Leparc-Goffart N 5

6 Dynamic of the first 2 months of the outbreak in Saint Martin Case definition: Chikungunya Fever >38,5 C of brutal appearance Dengue Fever >38,5 C of brutal appearance Joint pain in the extremities At least one of the following clinical signs: headache, arthralgia, myalgia, back pain, retroorbital pain, musculo-articular pain Absence of other etiological orientations Absence of other etiological orientations All samples (1502) from patients with the Chikungunya case definition were sent to the NRCA Diagnostic strategy 7 days : viral genome detection by RT PCR (Pastorino et al. J Virol Methods 124 (2005) 65 71) 5 days: Serology techniques, IgM and IgG detection (in house ELISA) N 6

with CHIKV clinical case definition Confirmed

7 Dynamic of the first 2 months of the outbreak in Saint Martin Confirmed CHIKV and DENV in patients with CHIKV clinical case definition Confirmed DENV in patients with DENV clinical case definition Omarjee et al. 2014, Eurosurveillance Data from French Institute for Public Health surveillance, N 7

8 Number of cases Number of co-infected cases Dengue viruses and chik co-circulation DENV confirmed cases (40 cases) Dengue virus serotype repartition 2,8% of co-infection CHIKV and DENV (16 cases) Dengue virus serotype repartition DENV-1 DENV-2 DENV-3 DENV-4 0 DENV-1 DENV-2 DENV-3 DENV-4 Dengue Serotypes Serotypes Omarjee et al. 2014, Eurosurveillance N 8

9 What did we learn from this epidemic? Is a case definition useful with Dengue and Chikungunya co circulation? Kinetic of infection in human with Chikungunya Asian genotype? Blood donors study: dynamics of the outbreak Kick-off Meeting REACTing I. Leparc-Goffart N 9

10 Viral load (Log TCID 50/ml) Viral load and viremia 7 n=40 n=206 n=199 n=137 n=69 n=43 n=19 n=20 N= Unpublished datta EFS data confirmation Days post symptoms onset N 10

11 % Kinetic of viremia and immune response RT-PCR IgM and RT-PCR IgM 100 n=41 n=92 2,4 2,2 n=94 n=101 n=103 n=103 n=51 n=41 n=11 1,1 3,2 2 9,1 5,8 n=7 * * * * * 80 27, , ,7 58, , ,6 85,7 Unpublished datta 0 97,6 97,8 95,7 88, ,8 17,6 24,3 14, Days post symptoms onset 100% IgG at day 12 post symptoms onset N 11

12 What did we learn from this epidemic? Is a case definition useful with Dengue and Chikungunya co circulation? Kinetic of infection in human with Chikungunya Asian genotype? Blood donors study: dynamics of the outbreak in Martinique and Guadeloupe islands Kick-off Meeting REACTing I. Leparc-Goffart N 12

13 Incidence in blood donors (~6 000) From 24/02/2014 a CHIKV-NAT screening. Dedicated laboratory in Marseille using the RealStar Chikungunya RT-PCR Kit 1.1 (Altona Diagnostics) No case of CHIKV transmission by blood products N 13

14 CHIKV infection prevalence in blood donors (~10 000) N 14

15 Comparison with the 2006 Reunion Island outbreak La Reunion Caribbean 2014 Vector Ae albopictus Ae aegypti Virus genotype ECSA Asian Epidemic pattern 2 seasons; explosive 1 season; explosive Final seroprevalence ~40% ~50% General population Blood donors Symptomatic - asymptomatic - atypical presentations asymptomatic or no typical presentation (fever and arthralgia) 16.7% - fever + arthralgia: 54.9% - mild arthralgia without fever 17.6% - febrile non-arthralgic Sd 11.8% - asymptomatic 15.7% Patients without a typical presentation: 45.1% Patients without any arthralgia: 27.5% Patients without fever: 33.3%* Chronic arthralgia Yes Yes (to be further evaluated) * Limited value of post-donation reporting of febrile syndromes Kick-off Meeting REACTing I. Leparc-Goffart N 15

16 acknowledgments French National Reference Center for Arboviruses (IRBA): UMR D190 «Virus Emergents» French Blood Bank French Public Health Institute (InVS, CIRE) Health Regional Agency (ARS) Cliniciens, Biologists Martinique, Guadeloupe and Cayenne Hospitals N 16

Dengue & Chikungunya In Asia Strategies for Testing

Dengue & Chikungunya In Asia Strategies for Testing Sally Lam Blood Services Group Health Sciences Authority Singapore 1 The Viruses - Arboviruses Flavivirus DENGUE Enveloped virus, ~50 nm in diameter