MERS H7N9. coronavirus. influenza virus. MERS: Since September 2012: 160 cases, including 68 deaths (42%)

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1 MERS coronavirus H7N9 influenza virus Marc Van Ranst, KU Leuven MERS: Since September 2012: 160 cases, including 68 deaths (42%) MERS coronavirus patient, 83 years, Saudi-Arabia H7N9: Since February 2013: 137 cases, including 45 deaths (33%) Emerging Microbes & Infection, Liu et al., May 8, 2013: H7N9

2 MERS-CoV

3 2003

4 Search term: MERS coronavirus

5 Search term: MERS coronavirus

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7 Between April 1 and May 23, 2013, a total of 23 cases of MERS-CoV infection were reported in the eastern province of Saudi Arabia. Symptoms included fever in 20 patients (87%), cough in 20 (87%), shortness of breath in 11 (48%), and gastrointestinal symptoms in 8 (35%); 20 patients (87%) presented with abnormal chest radiographs. As of June 12, a total of 15 patients (65%) had died, 6 (26%) had recovered, and 2 (9%) remained hospitalized. The median incubation period was 5.2 days (95% confidence interval [CI], 1.9 to 14.7), and the serial interval was 7.6 days (95% CI, 2.5 to 23.1). A total of 21 of the 23 cases were acquired by person-to-person transmission in hemodialysis units, intensive care units, or in-patient units in three different health care facilities. Sequencing data from four isolates revealed a single monophyletic clade. Among 217 household contacts and more than 200 health care worker contacts whom we identified, MERS-CoV infection developed in 5 family members (3 with laboratory-confirmed cases) and in 2 health care workers (both with laboratory-confirmed cases). Assiri et al., NEJM 2013, 369:

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10 Bermingham et al., 2012

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12 H7N9

13 2009

14 Search term: H7N9

15 Search term: H7N9

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17 Western Pacific Surveillance and Response Journal, 2013, 4(2). doi: /wpsar Western Pacific Surveillance and Response Journal, 2013, 4(2). doi: /wpsar

18 H7N9 case fatality rate Novel H7N9 influenza virus shows low infectious dose, high growth and efficient contact transmission in the guinea pig model Gabbard et al., 2014 (Department of Infectious Diseases, University of Georgia, Athens, Georgia) Sequencing of the viral genome revealed a number of molecular signatures associated with virulence or transmission in mammals. Here we report that, in the guinea pig model, a human isolate of novel H7N9 influenza virus, A/Anhui/1/2013 (An/13), is highly dissimilar to an H7N1 avian isolate and instead behaves similarly to a human seasonal strain in several respects. An/13 was found to have a low 50% infectious dose, grow to high titers in the upper respiratory tract, and transmit efficiently among co-caged guinea pigs. The ph of fusion of the HA and the binding of virus to fixed guinea pig tissues were also examined. The An/13 HA displayed a relatively elevated ph of fusion characteristic of many avian strains, and An/13 resembled avian viruses in terms of attachment to tissues. One important difference was seen between An/13 and both the H3N2 human and H7N1 avian viruses: when inoculated intranasally at high dose, only the An/13 virus led to productive infection of the lower respiratory tract of guinea pigs. In sum, An/13 was found to retain fusion and attachment properties of an avian influenza virus but displayed robust growth and contact transmission in the guinea pig model atypical of avian strains and indicative of mammalian adaptation.

19 Novel H7N9 influenza virus shows low infectious dose, high growth and efficient contact transmission in the guinea pig model Gabbard et al., 2014 (Department of Infectious Diseases, University of Georgia, Athens, Georgia) Novel H7N9 influenza virus shows low infectious dose, high growth and efficient contact transmission in the guinea pig model Gabbard et al., 2014 (Department of Infectious Diseases, University of Georgia, Athens, Georgia)

20 Humans Pigs Chickens Ducks

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23 MERS coronavirus H7N9 influenza virus Two recently discovered viruses and diseases <200 laboratory-confirmed cases Relatively geographically confined epidemic focus CFR 20-40% R0 about 1 Mostly older people, often with comorbidities Men >> women Unknown number of mild or asymptomatic patients Unknown animal or environmental reservoir Unknown future pandemic potential