IDCU HomeInfectious Diseases A-CD-GH-LM-QR-ST-ZIDCU Health TopicsDisease ReportingRelated Rules & RegulationsImmunization BranchAbout IDCURelated DSHS SitesStaff Contact List
  • Loading...
    Contact Us

    Infectious Disease Control Unit
    Mail Code: 1960
    PO BOX 149347 - Austin, TX 78714-9347
    1100 West 49th Street, Suite T801
    Austin, TX 78714

    Phone: 512 776 7676
    Fax: (512) 776-7616


    E-mail

Week 16

Loading...

Surveillance

 

Influenza
(Flu)
ICD-9 487; ICD-10 J10,11
Related Topics: Protecting Yourself During the Cold and Flu Season, Avian Flu, Vaccine Preventable Diseases, Asthma and SARS

2008 - 2009 Texas Influenza Surveillance Information

Influenza Surveillance Report for MMWR Week 16

The influenza (flu) activity level for Texas for the week ending April 25, 2009 was “local.” During week 16, no specimens tested by NREVSS laboratories in Texas were positive for influenza. The percentage of visits for influenza-like illness as reported by ILINet providers in Texas was below the regional baseline.

 

Reports from Health Service Regions

Reports were received from all Health Service Regions (HSRs) for week 16; however, due to the current swine influenza A/H1N1 investigations, regular reports from many sentinel providers were not received by the HSRs. HSR 4/5N reported an increased level of flu activity compared to week 15. HSRs 6/5S and 8 reported the same level of flu activity compared to week 15. All other HSRs reported a decreased level of flu activity compared to week 15. For a map of Health Service Regions, please visit the following website: http://www.dshs.state.tx.us/regions/state.shtm

 

Laboratory Results

During week 16, five hospital laboratories and public health agencies across Texas reported conducting a total of 138 influenza tests (antigen, culture, and PCR) to the National Respiratory and Enteric Virus Surveillance System (NREVSSnew window) sponsored by the Centers for Disease Control and Prevention (CDC). No tests were positive for influenza.

A total of 12 reports of PCR- or culture-confirmed influenza were received from public health laboratories and the United States Air Force School of Aerospace Medicine (USAFSAM) for the following counties during week 16 (April 19-April 25):

 

Influenza A/H1 (seasonal) Influenza A/H3 Influenza A/not subtyped Influenza B
Bexar County (2) (none) (none) Bexar County (3)
Travis County     Wichita County (5)
Wichita County      

Positive point-of-care rapid tests for influenza were reported by providers throughout the state (see county map below).

Novel Influenza A Virus Infections (information updated 5/15/09)

A total of 52 cases of influenza A/H1 swine confirmed by the CDC have been reported with a known onset in week 16 (April 19-April 25) for the following counties (listed by patient county of residence):
Influenza A/H1 swine
Bexar County (5)
Cameron County
Comal County (2)
Dallas County (4)
Denton County
Fort Bend County (2)
Guadalupe County (10)
Harris County (3)
Hidalgo County
Jefferson County
Johnson County
Kendall County
Montgomery County
Starr County (5)
Tarrant County (11)
Taylor County
Travis County
Upshur County

Additional specimens have been identified by PCR testing as positive for unsubtypeable influenza A; these specimens are being forwarded to CDC for further study. This information is subject to change as more reports are received. Thorough case and contact investigations are ongoing, and the number of confirmed cases changes frequently. Please see the DSHS website (http://www.dshs.state.tx.us/swineflu/default.shtm) and the CDC website (http://www.cdc.gov/flu/swine/) for more information on the current investigation.

Antigenic Characterization

CDC has reported antigenic characterization results from 48 influenza isolates [20 influenza A/H1, 6 influenza A/H3, and 22 influenza B viruses] received from the DSHS Laboratory since the beginning of the 2008–09 flu season.

Influenza A/H1 [20]

  • All 20 viruses were characterized as A/Brisbane/59/2007, the influenza A/H1 component of the 2008–09 influenza vaccine for the Northern Hemisphere.
Influenza A/H3 [6]
  • All 6 viruses were characterized as A/Brisbane/10/2007, the influenza A/H3 component of the 2008-09 influenza vaccine for the Northern Hemisphere.
Influenza B (B/Victoria/02/87 and B/Yamagata/16/88 lineages) [22]
    Victoria lineage [15]
  • Fifteen of the influenza B viruses were characterized as belonging to the B/Victoria lineage.
    Yamagata lineage [7]
  • Seven viruses were characterized as B/Florida/4/2006, the influenza B component for the 2008-09 influenza vaccine for the Northern Hemisphere.

Antiviral Resistance

Since September 28, 2008, 21 seasonal influenza A/H1 isolates, 6 influenza A/H3 isolates, and 21 influenza B isolates from the DSHS laboratory have been tested by CDC for antiviral resistance.
  Isolates Tested (n) Resistant Viruses,
Number (%)
Isolates Tested (n) Resistant Viruses,
Number (%)
Oseltamivir Zanamivir Adamantanes
Influenza A/H1 21 21 (100%) 0 (0) 21 0 (0)
Influenza A/H3 6 0 (0) 0 (0) 6 6 (100%)
Influenza B 21 0 (0) 0 (0) N/A* N/A*
                                     *Adamantanes are not effective against influenza B viruses.                                      

CDC has issued interim recommendations for use of antiviral medications in the 2008-09 influenza season. Those recommendations are available at: http://www.cdc.gov/flu/professionals/antivirals/index.htm..

 

Influenza-Associated Pediatric Mortality

No influenza-associated pediatric fatalities in Texas residents were reported during week 16. Texas has reported ten influenza-associated pediatric fatalities during the 2008-09 influenza season.

 

School Closures and Institutional Outbreaks

School closures were reported in HSR 8 (Guadalupe County) during week 16. For more information on school closures, please see http://ritter.tea.state.tx.us/swineflu/schclosings.html.

 

U.S. Outpatient Influenza-like Illness Surveillance Network

Sixty-four providers in Texas reported data to the U.S. Outpatient Influenza-like Illness Surveillance Network (ILINet) (formerly known as the U.S. Influenza Sentinel Provider Surveillance System) on patients with influenza–like illness (ILI) and total patients seen for any reason during week 16. Of the 62 providers who reported seeing patients during week 16, 22 (35%) saw at least one patient with ILI. Of all patient visits during this week, 2.19% were due to ILI. The ILI baseline for the West South Central Region (Arkansas, Louisiana, Oklahoma, and Texas) of the United States is 4.8% for the 2008-2009 season. The baseline is the mean percentage of patient visits for ILI during non-influenza weeks for the previous three seasons plus two standard deviations.
Percentage of Visits for Influenza–Like Illness Reported by the US Outpatient Influenza–Like Illness Surveillance Network (ILINet) in Texas as of 5/1/2009 7:28:50 PM
Week # Reporting Age 0-4 Age 5-24 Age 25-64 Age over 64 Total ILI Total Patients % ILI
2008-40 78 84 133 127 22 366 20333 1.80
2008-41 78 114 163 124 19 420 20105 2.09
2008-42 79 107 156 90 7 360 19746 1.82
2008-43 79 120 152 106 20 398 19740 2.02
2008-44 81 136 199 104 26 465 20972 2.23
2008-45 78 110 111 122 27 370 20835 1.78
2008-46 73 110 106 103 23 342 19771 1.73
2008-47 75 137 143 122 19 421 19806 2.13
2008-48 79 131 132 125 37 425 16905 2.51
2008-49 77 143 159 153 24 479 20343 2.35
2008-50 75 133 146 108 28 415 19330 2.15
2008-51 69 172 177 175 24 548 17531 3.13
2008-52 76 194 153 154 34 535 13431 3.98
2008-53 77 176 141 165 46 528 15222 3.47
2009-01 78 162 182 188 38 570 18518 3.08
2009-02 77 178 287 235 41 741 20094 3.69
2009-03 78 174 468 341 43 1026 22951 4.47
2009-04 78 260 679 332 47 1318 24244 5.44
2009-05 73 282 883 465 40 1670 24590 6.79
2009-06 79 301 964 391 59 1715 24162 7.10
2009-07 79 320 814 316 57 1507 25873 5.82
2009-08 73 221 552 283 57 1113 24526 4.54
2009-09 76 194 422 244 71 931 22293 4.18
2009-10 79 221 324 212 77 834 22341 3.73
2009-11 75 167 268 178 58 671 19207 3.49
2009-12 70 109 150 179 18 456 20542 2.22
2009-13 69 114 141 163 16 434 18183 2.39
2009-14 75 158 194 232 51 635 20188 3.15
2009-15 68 86 129 144 19 378 19770 1.91
2009-16 64 84 152 154 25 415 18922 2.19


Percentage of Visits Due to Influenza-Like Illness (ILI) Texas Providers in the U.S. Outpatient Influenza-like Illness Surveillance Nethwork 2008-2009

 

Influenza-Like Illness (ILI) Data Texas Providers in the U.S. Outpatient Influenza-like Illness Surveillance Nethwork Flu Seasons 2004-2009

 

National Influenza Activity Map

The current U.S. flu weekly report may be found at http://www.cdc.gov/flu/weekly/fluactivity.htm.

For more information on flu surveillance activities in the State of Texas, please visit our main surveillance page.





  • Loading...
Last updated July 12, 2012