952. Estimating Risk to Humans Exposed to Highly Pathogenic Avian Influenza Outbreaks in the United States, 2014-2017
Session: Oral Abstract Session: Public Health Potpourri
Friday, October 6, 2017: 9:00 AM
Room: 07AB

Background: In the US, poultry outbreaks of highly pathogenic avian influenza viruses (AI) caused by H5 and H7 viruses have raised concern about the risk of infections in humans. Based on data from Asian lineage H5 and H7 AI, which sporadically transmit from poultry to humans, CDC currently recommends active daily monitoring of persons exposed to H5 and H7 AI viruses, including those who wear personal protective equipment (PPE).

Methods: Persons exposed to HPAI infected birds or contaminated environments in the US were actively monitored during exposure and for 10 days post-exposure for illness, during 2014-2017. Some exposed persons were monitored on-site by USDA or contract safety officers, company staff, or state health officials. State health department staff monitored people during the 10-day post-exposure period. Persons reporting any respiratory illness or conjunctivitis were swabbed for molecular influenza testing.  Preliminary results are presented.

Results: From 2014-2017, 270 detections in poultry/wild birds were reported and at least 606 persons were potentially exposed to AI virus by exposure to birds, carcasses, or environment. Most exposed persons wore PPE. No human infections with AI viruses were detected.

Conclusion: The risk of transmission of these H5 and H7 AI viruses to humans was low. These preliminary data offer evidence to change the recommendations for monitoring in persons exposed to these viruses. If final data support these findings, self-monitoring by workers with reporting to health departments if symptoms develop, rather than active monitoring by public health personnel, could be considered. However, it will be important to reconsider and update recommendations as the viruses evolve. Furthermore, risk of infection likely varies by exposure and those without PPE should be actively monitored.

Year

HPAI virus

No. detections reported

Estimated no. birds destroyed

No. persons exposed

No. HPAI positive / no. ill and tested

Percent ill of all exposed (95% exact binomial confidence interval)

Dec 2014–Jun 2015

H5N2

H5N8

H5N1

H5

241

22

2

15,639,861

     254,669

                 0

103

  56

    3

    2

164

0/5

0 (0-0.02)

2016

H7N8

H5N2

1

1

       42,600

                 0

319

Missing

0/20

Missing

0 (0-0.01)

 

2017

H7N9

H5N2

2

1

     127,956

                 0

123

Missing

0/1

Missing

0 (0-0.03)

 

 

Sonja Olsen, PhD1, Fiona Havers, MD, MHS1, Melissa Rolfes, PhD, MPH1, Lenee Blanton, MPH1, Jane Rooney, DVM2, Thomas Gomez, DVM, MS3, Deborah Nelson, PhD2, Steven Karli, MD4, Susan C. Trock, DVM, MPH1 and Alicia M. Fry, MD, MPH1, (1)Influenza Division, Centers for Disease Control and Prevention, Atlanta, GA, (2)Animal and Plant Health Inspection Service, US Department of Agriculture, Fort Collins, CO, (3)Animal and Plant Health Inspection Service, US Department of Agriculture, Atlanta, GA, (4)Animal and Plant Health Inspection Service, US Department of Agriculture, Riverdale, MD

Disclosures:

S. Olsen, None

F. Havers, None

M. Rolfes, None

L. Blanton, None

J. Rooney, None

T. Gomez, None

D. Nelson, None

S. Karli, None

S. C. Trock, None

A. M. Fry, None

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