Weekly Report 2017 Week 2 (January 8 – January 14, 2017) through 2018 Week 2 (January 7 – January 13, 2018)

Department of Health and Human Services

Office of Analyt ics

Brian Sandoval

Governor

State of Nevada

Richard Whitley, MS

Director

Department of Health and Human Services

Julie Kotchevar, Ph.D

Acting Administrator

Division of Public and Behavioral Health

January, 2018

Edition 1.0

Influenza Weekly Report v 2018 i 2 (January 7 – January 13, 2018)

Page 1 of 5

Data for the graphs and tables on the following pages are provisional and may be updated as additional information becomes available.

Purpose

The purpose of this report is to provide an overview of and statistics for the influenza season in Nevada for the local public health authorities, sentinel

providers and the public.

Sentinel Provider Data: Influenza-Like Illness Network Surveillance (ILINet)

Respiratory specimens are tested for influenza by the World Health Organization (WHO) and National Respiratory and Enteric Virus Surveillance

System (NRVESS) collaborating laboratories by sub-type. During week 2, there were 52,677 specimens collected and tested for influenza, of those

14,401 were positive (27.3%).

Figure 1

Source of Data: CDC: FluView Weekly Report.

The Nevada total includes laboratory tests for all Nevada residents tested by sentinel providers including out of state laboratories. Laboratory data

is obtained from CDC’s ILINet system. During week 2, where there were 21 specimens collected, in which 15 were positive. There is a two-week

delay for laboratory surveillance. Data are subject to change as we receive additional reports.

Figure 2

Source of Data: CDC: ILINet.

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National Influenza Positive Tests by Week53 Week Comparison (2017 WK 2 - 2018 WK 2)

2009H1N1 A(H3) A(Unknown Subtyping) B (Victoria Lineage)

B (Yamagata Lineage) B(Unknown Subtyping) Percent Positive

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Nevada (ILI Providers) Influenza Laboratory Confirmed Positive by Week53 Week Comparison (2017 WK 2 - 2018 WK 2)

2009H1N1 A(H3) A(Subtyping not performed) B (Victoria Lineage)B (Yamagata Lineage) B(Unknown Subtyping) Percent Positive

Influenza Weekly Report v 2018 i 2 (January 7 – January 13, 2018)

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Nevada State Public Health Laboratory (NSPHL) has tested 326 specimens for influenza from sentinel providers, of which there have been 276

positive (84.7%). Southern Nevada Public Health Laboratory (SNPHL) has tested 37 specimens this season of which there have been 4 positive.

Nationally, there have been 480,349 specimens sent to the WHO and NERVSS laboratories of which 81,771 have been positive (17.0%). The

national numbers in Table 1 are reflected in Figure 1. The state of Nevada data in Table 1 is reflected in Figure 2. The Nevada total includes

laboratory test for all Nevada residents tested by sentinel providers, including out of state laboratories.

Table 1

Influenza Specimens Tested State and Nationally through Sentinel Providers

NSPHL

SNPHL All Other

Laboratories

State of Nevada (Week 2)

State of Nevada (Season)

National (Week 2)

National (Season)

# % # % # % # %

Specimens Tested 326 37 585 21 - 948 - 52,677 480,349

Influenza Positives 276 4 166 15 71.4 446 47.0 14,401 27.3 81,771 17.0

Influenza A: 240 3 157 11 73.3 400 89.7 11,941 82.9 68,357 83.6

A (2009 H1N1) 13 0 0 0 0.0 13 3.3 118 1.0 1,219 1.8

A (H3) 227 3 5 11 100.0 235 58.8 1,111 9.3 12,489 18.3

A (Sub-typing not performed) 0 0 152 0 0.0 152 38.0 10,712 89.7 54,649 79.9

Influenza B: 36 1 9 4 26.7 46 10.3 2,460 17.1 13,414 16.4

B (Victoria Lineage) 0 0 0 0 0.0 0 0.0 11 0.4 123 0.9

B (Yamagata Lineage) 36 0 1 4 100.0 37 80.4 112 4.6 1,366 10.2

B (Sub-typing not performed)

0 1 8 0 0.0 9 19.6 2,337 95.0 11,925 88.9

Source of Data: CDC: FluView Report and CDC: ILINet.

Influenza-like Illness (ILI) Surveillance Network has each sentinel provider report the number of patients seen that meet the ILI case definition

and the total number of patients seen for any reason each week. The “percentage of visits for ILI” is the number of ILI patients divided by the total

number of patients visit per week. Nevada’s percentage of ILI visits for week 2 is 4.7% which is above the state baseline of 1.5%. Region 9 ILI

percentage for week 2 is 6.1% which is the above the region baseline of 2.4%. Region 9 includes the following states/territory: Arizona,

California, Guam, Hawaii, and Nevada. The national ILI percentage for week 2 is 5.8% which is above the national baseline 2.2%.

Figure 3

Source of Data: CDC: Flu View Report and CDC: ILINet.

During week 2, 4.7% of visits to sentinel providers were due to ILI; this is greater than the 2016-2017 influenza season (1.7%). There were

11,358 patients seen by sentinel providers during week 2, of which 538 patients presented with ILI; week 2 of 2017, there were 292 patients

seen with ILI (17,572 total patients seen). Data availability depends on sentinel provider reporting.

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Percentage of Visits for ILI Reported to Outpatient ILI Surveillance Network,Comparison Between National, Regional, and State,

53 Week Comparison (2017 WK 2 - 2018 WK 2)

Nevada Region 9 National

Nevada Baseline Region 9 Baseline National Baseline

Influenza Weekly Report v 2018 i 2 (January 7 – January 13, 2018)

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Figure 4

Source of Data: CDC: ILINet.

Influenza-like Illness is reported by age groups. During week 2, patients ages 0-4 were the greatest number of patients seen with ILI, at 132 patients

seen. The rate for week 2 is 18.1 per 100,000 population. The rate is calculated by the number of patients presented with ILI, divided by the state

population, multiplied by 100,000. The estimated state population for 2018 is 2,969,849.

Figure 5

Source of Data: CDC: ILINet.

Influenza Positive Surveillance (NBS and NETSS)

Positive cases of influenza are reported to the state health authority for surveillance purposes. Table 2 and Figure 6 reflect all positive influenza cases

reported to the state. Types of influenza testing include commercial rapid diagnostic test (rapid), viral culture, fluorescent antibody, enzyme

immunoassay, RT-PCR (PCR), and Immunohistochemistry. The two most common test types in Nevada are Rapid and PCR tests. During week 2, there

were 1,404 influenza cases reported to the state, 1,030 influenza A, 305 influenza B and 69 unknown subtyping.

Table 2

Reporting Jurisdiction

Reported Influenza Cases by County Jurisdiction and Influenza Type

Current Week (Week 2) Cumulative Influenza Season

A B Unknown Total A B Unknown Total

Carson City Health and Human Services 162 71 9 242 861 170 23 1,054

Rural Community Health Services 100 26 10 136 671 77 12 760

Southern Nevada Health District 443 102 23 568 4949 442 81 5,472

Washoe County Health District 325 106 27 458 2569 524 260 3,353

State of Nevada 1,030 305 69 1,404 9,050 1,213 376 10,639

Source: to Office of Analytics: NBS and SNHD: NETSS.

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Nevada Percentage of Visits for Influenza-like Illness, Weekly Summary53 Week Comparison (2011-2018)

2016 WK 02 - 2017 WK 02 2015 WK 02 - 2016 WK 02 2014 WK 02 - 2015 WK 02

2013 WK 02 - 2014 WK 02 2012 WK 02 - 2011 WK 02 Baseline

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ILINet: Influenza-like Illness by Age Group and MMWR Week and Incidence Rate 53 Week Comparison (2017 WK 1 - 2018 WK 1)

0-4 5-24 25-49 50-64 65+ Rate

Influenza Weekly Report v 2018 i 2 (January 7 – January 13, 2018)

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Figure 6

Source of Data: to Office of Analytics: NBS and SNHD: NETSS.

Hospitalizations

There were 108 hospitalizations associated with influenza reported to the state health authority for week 2.

Table 3

Influenza Hospitalizations

Reporting Jurisdiction Current Week (Week 2) Cumulative Influenza Season # % # %

Carson City Health and Human Services 18 16.7% 98 9.5% Rural Community Health Services 4 3.7% 31 3.0%

Southern Nevada Health District 86 79.6% 567 55.2% Washoe County Health District 0 0.0% 331 32.2%

State of Nevada 108 100.0% 1027 100.0% Source: Reported to Office of Analytics from each Jurisdiction.

Pneumonia and Influenza (P&I) Mortality Surveillance

The Pneumonia and Influenza (P&I) mortality percentage is all deaths, where Pneumonia or Influenza is listed as the underlying or contributing cause

of death, divided by the total deaths in Nevada for each week. As of January 22nd, there were 61 P&I deaths and 399 total deaths for week 2 in Nevada.

Please note that the CDC does not have updated P&I counts for week 1 or week 2.

Figure 7

Source: OVR: WEVRRS and CDC: FluView.

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Weekly Reported Influenza by Subtype as Compared with Respiratory Syncytial Virus Infections (RSV) 53 Week Comparison (2017 WK 2- 2018 WK 2)

Influenza A Influenza B Unknown Influenza Subtyping RSV

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Pneumonia and Influenza (P&I) Mortality by Week,NCHS Mortality Data Compared to Nevada

53 Week Comparison (2017 WK 2 - 2018 WK 2)

Nevada National National Epidemic Threshold

Influenza Weekly Report v 2018 i 2 (January 7 – January 13, 2018)

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Technical Notes • Data are subject to changes, additionally, there is a lag in reporting.

• Influenza surveillance procedures vary by jurisdiction.

• Influenza-like illness (ILI): a fever greater than or equal 100℉ with cough and/or sore throat.

• Percent positive: The number of positive influenza laboratory tests divided by the total number of tests performed.

• Incidence rate is per 100,000 population as estimated by the state demographer.

This report contains information from national and state-level data sources. Influenza surveillance data is collected by a various systems,

including:

• Influenza-like Illness Network (ILINet): a sentinel surveillance system in collaboration with the Centers for the Disease Control and

Prevention (CDC) where outpatient providers report ILI information weekly.

• National Electronic Telecommunication System for Surveillance (NETSS): a system whereby data is transmits to CDC. Influenza

data collected through NETSS does not provide influenza sub-typing information.

• National Electronic Disease Surveillance System (NEDSS): a system for collecting data and monitoring disease trends and

outbreaks.

• NEDSS Based System (NBS): an implementation of the NEDSS standards. It provides a secure, accurate, and efficient means of

collecting, transmitting, and analyzing public health data.

Citations

1. CDC. FluView: A Weekly Influenza Surveillance Report. http://www.cdc.gov/flu/weekly/pastreports.htm.

2. Nevada State Demographer’s Office. 2003-2020 ASRHO Estimates and Projections. Division of Public and Behavioral Health edition.

Vintage 2015.

3. Office of Analytics. DHHS. NBS. 2016-2018. Accessed January 2018.

4. Office of Vital Records (OVR). DPBH. Web Enabled Vital Records Registry System (WEVRRS) [unpublished data]. 2017-2018. Accessed

January 2018.

5. Southern Nevada Health District (SNHD). NETSS/Trisano. 2016-2018. Accessed January 2018.

Comments, suggestions, and requests for further information may be addressed to:

NEVADA INFLUENZA SURVEILLANCE PROGRAM

OFFICE OF ANALYTICS

4126 TECHNOLOGY WAY

CARSON CITY, NV 89706

TEL: (775) 684-5997

FAX: (775) 684-5999

Compiled and Written by: Helen See, MPH

Reviewed by: Jennifer Thompson

Melissa Peek-Bullock

Recommended Citation:

Department of Health and Human Services. Office of Analytics. Influenza Weekly Report, 2017 Week 2 (January 8, 2017) through 2018 Week 2

(January 13, 2018), Nevada. January 2018 i 2 edition 1.0.

This publication was supported by Cooperative Agreement Number TP000534-02 from the Centers for

Disease Control and Prevention and/or Assistant Secretary for Preparedness and Response. Its contents

are solely the responsibility of the authors and do not necessarily represent the official views of the

Centers for Disease Control and Prevention and/or Assistant Secretary for Preparedness and Response.