2008 - 2009 Texas Influenza Surveillance Information
Influenza Surveillance Report for MMWR Week 39
The influenza (flu) activity level for Texas for the week ending October 3, 2009 was “widespread.” For definitions of flu activity levels please see http://www.cdc.gov/flu/weekly/fluactivity.htm. During week 39, 1,037 (29.9%) 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 above the regional baseline during week 39.
Reports from Health Service Regions
Reports were received from all Health Service Regions (HSRs) for week 39. HSRs 1, 7, 8, and 11 reported an increased level of flu activity compared to week 38. HSR 2/3, 6/5S and 9/10 reported the same level of flu activity compared to week 38. HSR 4/5N reported a decreased level of flu activity compared to week 38. For a map of Health Service Regions please visit the following website: www.dshs.state.tx.us/regions/state.shtm Laboratory Results
During week 39, thirteen hospital laboratories and public health agencies across Texas reported conducting a total of 3,469 influenza tests (antigen, culture, and PCR) to the National Respiratory and Enteric Virus Surveillance System (NREVSS ) sponsored by the Centers for Disease Control and Prevention (CDC). The majority (73%) of influenza tests reported to NREVSS were antigen detection tests; these tests cannot identify the subtype of influenza detected. The results from Texas participants in NREVSS are summarized in the table below.
Testing Information |
Week 39 |
No. of specimens tested |
3,469 |
No. of positive specimens (%) |
1,037 (29.9%) |
Positive specimens by type/subtype |
Influenza A |
1,037 (100%) |
A (novel H1N1) |
340 (32.8%) |
A (subtyping not performed) |
697 (67.2%) |
A (unable to subtype) |
0 (0%) |
A (H3) |
0 (0%) |
A (seasonal H1) |
0 (0%) |
Influenza B |
0 (0%) |
Additional influenza test results (rapid tests, culture, PCR) were reported from providers and public health departments throughout the state (see county map below).
Novel Influenza A Virus Infections
Please see the Texas Department of State Health Services (DSHS) novel influenza website (http://www.texasflu.org) and the CDC website (http://www.cdc.gov/h1n1flu/) for more information. Data collection for confirmed novel influenza A (H1N1) hospitalizations, intensive care unit (ICU) admissions, and deaths began in Texas on September 20, 2009. The table below summarizes the current data.
Cumulative Surveillance Case Summary for Novel Influenza A (H1N1) by Health Service Region and County as of 10/3/2009 |
Health Service Region or County |
Hospitalizations* |
Intensive Care Unit (ICU) Admissions* |
Deaths** |
Region 1 |
Lubbock County |
4 |
4 |
2 |
Region 1 Total |
4 |
4 |
2 |
Region 2/3 |
Collin County |
2 |
0 |
0 |
Dallas County |
50 |
5 |
8 |
Denton County |
1 |
0 |
0 |
Ellis County |
1 |
0 |
0 |
Fisher County |
1 |
1 |
0 |
Kaufman County |
2 |
0 |
0 |
Tarrant County |
30 |
5 |
1 |
Region 2/3 Total |
87 |
11 |
9 |
Region 4/5N |
Bowie County |
2 |
1 |
1 |
Gregg County |
5 |
1 |
0 |
Lamar County |
1 |
1 |
0 |
Rusk County |
2 |
1 |
1 |
Shelby County |
1 |
0 |
0 |
Smith County |
7 |
2 |
2 |
Van Zandt County |
0 |
0 |
1 |
Region 4/5N Total |
18 |
6 |
5 |
Region 6/5S |
Brazoria County |
0 |
0 |
1 |
Fort Bend County |
6 |
3 |
2 |
Harris County |
8 |
3 |
4 |
Jefferson County |
2 |
1 |
0 |
Region 6/5S Total |
16 |
7 |
7 |
Region 7 |
Bastrop County |
0 |
0 |
1 |
Bell County |
2 |
0 |
1 |
Burleson County |
1 |
0 |
0 |
Caldwell County |
1 |
1 |
0 |
Hamilton County |
1 |
0 |
0 |
Hays County |
2 |
1 |
0 |
McLennan County |
5 |
0 |
0 |
Travis County |
9 |
1 |
2 |
Williamson County |
4 |
0 |
0 |
Region 7 Total |
25 |
3 |
4 |
Region 8 |
Bexar County |
17 |
4 |
9 |
Dimmit County |
1 |
0 |
0 |
Frio County |
1 |
0 |
0 |
Gonzales County |
0 |
0 |
1 |
Maverick County |
3 |
0 |
1 |
Medina County |
1 |
0 |
0 |
Uvalde County |
1 |
0 |
0 |
Val Verde County |
1 |
0 |
1 |
Victoria County |
1 |
0 |
1 |
Wilson County |
1 |
1 |
0 |
Zavala County |
1 |
0 |
0 |
Region 8 Total |
28 |
5 |
13 |
Region 9/10 |
Andrews County |
0 |
0 |
1 |
El Paso County |
6 |
0 |
7 |
Hudspeth County |
1 |
0 |
0 |
Midland County |
2 |
0 |
0 |
Region 9/10 Total |
9 |
0 |
8 |
Region 11 |
Bee County |
6 |
0 |
0 |
Brooks County |
1 |
0 |
0 |
Cameron County |
5 |
1 |
3 |
Hidalgo County |
12 |
7 |
11 |
Jim Wells County |
2 |
0 |
0 |
Kleberg County |
7 |
0 |
0 |
Nueces County |
10 |
2 |
6 |
San Patricio County |
1 |
1 |
0 |
Webb County |
2 |
2 |
1 |
Region 11 Total |
46 |
13 |
21 |
Texas Total |
233 |
49 |
69 |
*Reporting for hospitalizations and ICU admissions began on 9/20/2009. ICU admissions are included in the hospitalization totals. **Reporting for deaths began 4/15/2009 and includes a child from Mexico.
Antigenic Characterization
CDC has reported antigenic characterization results from 51 seasonal influenza isolates [20 influenza A (H1N1), 8 influenza A (H3N2), and 23 influenza B viruses] and 8 novel influenza A (H1N1) viruses received from the DSHS Laboratory since the beginning of the 2008–09 flu season. Other laboratories in Texas submit influenza isolates to CDC for testing, but those results were not available for this report. Influenza A (H1N1) seasonal [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 (H3N2) [8]
- All 8 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) [23]
Victoria lineage [16] - Sixteen 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.
Novel influenza A (H1N1) [8]
- All 8 viruses were characterized as A/California/07/2009-like (H1N1), the reference virus selected by the World Health Organization (WHO) as a candidate for the novel influenza A (H1N1) vaccine.
Antiviral Resistance
Since September 28, 2008, 22 seasonal influenza A (H1N1) isolates, 8 influenza A (H3N2) isolates, and 23 influenza B isolates have been tested by CDC for antiviral resistance. Additionally, novel influenza A (H1N1) isolates from multiple Texas laboratories have been tested by CDC for antiviral resistance. Other laboratories in Texas submit influenza isolates to CDC for testing, but the majority of those results were not available for this report; however, information is available on additional novel influenza A (H1N1) isolates from Texas that were tested at CDC.
Flu Types/Subtypes |
Isolates Tested (n) |
Resistant Viruses, Number (%)
|
Isolates Tested (n) |
Resistant Viruses, Number (%)
|
Oseltamivir |
Zanamivir |
Adamantanes |
Influenza A (H1N1) (seasonal) |
22 |
22 (100) |
0 (0) |
22 |
0 (0) |
Influenza A (H3N2) |
8 |
0 (0) |
0 (0) |
7 |
7 (100) |
Influenza B |
23 |
0 (0) |
0 (0) |
N/A* |
N/A* |
Influenza A (H1N1) (novel) |
110 |
2 (2%) |
0 (0) |
42 |
42 (100%) |
*Adamantanes are not effective against influenza B viruses.
CDC has issued interim recommendations for use of antiviral medications in the 2009-10 influenza season. Those recommendations are available at: http://www.cdc.gov/h1n1flu/recommendations.htm.
Influenza–Associated Pediatric Mortality
Four new influenza-associated pediatric deaths occurred in week 39. The first death occurred in a 14-year-old resident of HSR 2/3 with no underlying medical conditions. A specimen from the child tested positive by PCR for novel influenza A (H1N1). The second death occurred in a 6-year-old resident of HSR 4/5N with significant underlying medical conditions. The child was positive via PCR testing for novel influenza A (H1N1). The third death occurred in a 9-year-old resident of HSR 4/5N with significant underlying conditions. The child's specimen tested positive for novel influenza A (H1N1) by PCR. The fourth death occurred in an 11-year-old resident of HSR 8 with significant underlying medical conditions. Although the child's specimen tested positive for influenza A by PCR, subtyping was not performed. Texas has reported 26 influenza-associated pediatric fatalities during the 2008-09 influenza season. School Closures and Institutional Outbreaks
Multiple school closures were reported during week 39. One school in Dallas County closed. School districts in Bowie, Henderson, and Wood counties closed due to increased absenteeism related to flu. Multiple campuses in Walker County closed due to faculty illness and absenteeism. DSHS has issued guidance for cases of ILI and novel influenza A (H1N1) in summer camps, schools, and congregate facilities. Please see http://www.texasflu.org for more information. U.S. Outpatient Influenza-like Illness Surveillance Network
Forty 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 39. Of these 39 providers who saw patients, 32 (82%) saw at least one patient with ILI. Of all patient visits during this week, 8.43% were due to ILI. The ILI baseline for HHS Region 6 (Arkansas, Louisiana, New Mexico, Oklahoma, and Texas) of the United States is 4.6% 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 10/08/2009 5:42:58 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 |
80 |
120 |
152 |
106 |
20 |
398 |
19857 |
2.00 |
2008-44 |
82 |
136 |
199 |
104 |
26 |
465 |
20972 |
2.22 |
2008-45 |
79 |
110 |
111 |
122 |
27 |
370 |
20959 |
1.77 |
2008-46 |
74 |
110 |
107 |
103 |
23 |
343 |
19890 |
1.72 |
2008-47 |
76 |
137 |
143 |
122 |
19 |
421 |
19907 |
2.11 |
2008-48 |
80 |
132 |
132 |
125 |
37 |
426 |
17012 |
2.50 |
2008-49 |
78 |
143 |
159 |
153 |
24 |
479 |
20446 |
2.34 |
2008-50 |
76 |
133 |
146 |
108 |
28 |
415 |
19450 |
2.13 |
2008-51 |
70 |
172 |
177 |
175 |
24 |
548 |
17663 |
3.10 |
2008-52 |
77 |
194 |
153 |
154 |
34 |
535 |
13509 |
3.96 |
2008-53 |
78 |
176 |
141 |
165 |
46 |
528 |
15329 |
3.44 |
2009-01 |
79 |
162 |
182 |
188 |
38 |
570 |
18646 |
3.06 |
2009-02 |
78 |
178 |
287 |
235 |
41 |
741 |
20222 |
3.66 |
2009-03 |
79 |
174 |
468 |
341 |
43 |
1026 |
23058 |
4.45 |
2009-04 |
79 |
260 |
679 |
333 |
47 |
1319 |
24350 |
5.42 |
2009-05 |
74 |
282 |
884 |
467 |
40 |
1673 |
24734 |
6.76 |
2009-06 |
80 |
301 |
965 |
392 |
59 |
1717 |
24320 |
7.06 |
2009-07 |
79 |
317 |
803 |
316 |
57 |
1493 |
25821 |
5.78 |
2009-08 |
74 |
221 |
552 |
283 |
57 |
1113 |
24664 |
4.51 |
2009-09 |
77 |
194 |
423 |
245 |
71 |
933 |
22428 |
4.16 |
2009-10 |
80 |
221 |
325 |
212 |
77 |
835 |
22635 |
3.69 |
2009-11 |
77 |
167 |
269 |
178 |
58 |
672 |
19656 |
3.42 |
2009-12 |
72 |
109 |
150 |
179 |
18 |
456 |
20910 |
2.18 |
2009-13 |
74 |
115 |
143 |
163 |
16 |
437 |
18760 |
2.33 |
2009-14 |
81 |
158 |
199 |
234 |
51 |
642 |
20963 |
3.06 |
2009-15 |
78 |
92 |
138 |
156 |
23 |
400 |
21254 |
1.92 |
2009-16 |
87 |
133 |
200 |
163 |
28 |
524 |
22058 |
2.38 |
2009-17 |
77 |
260 |
570 |
348 |
44 |
1222 |
25406 |
4.81 |
2009-18 |
72 |
200 |
361 |
185 |
31 |
777 |
22503 |
3.45 |
2009-19 |
65 |
125 |
253 |
183 |
24 |
585 |
19066 |
3.07 |
2009-20 |
63 |
122 |
255 |
134 |
7 |
518 |
19150 |
2.70 |
2009-21 |
64 |
115 |
221 |
111 |
31 |
478 |
17728 |
2.70 |
2009-22 |
61 |
108 |
188 |
88 |
14 |
398 |
18573 |
2.14 |
2009-23 |
55 |
79 |
103 |
29 |
9 |
220 |
10111 |
2.18 |
2009-24 |
53 |
65 |
119 |
79 |
4 |
267 |
16773 |
1.59 |
2009-25 |
59 |
72 |
114 |
79 |
15 |
280 |
16624 |
1.68 |
2009-26 |
59 |
68 |
105 |
75 |
13 |
261 |
15326 |
1.70 |
2009-27 |
58 |
72 |
90 |
72 |
15 |
249 |
16643 |
1.50 |
2009-28 |
61 |
44 |
101 |
78 |
15 |
238 |
17296 |
1.38 |
2009-29 |
59 |
67 |
101 |
73 |
14 |
255 |
16844 |
1.51 |
2009-30 |
55 |
25 |
41 |
23 |
11 |
100 |
9965 |
1.00 |
2009-31 |
59 |
56 |
92 |
95 |
9 |
252 |
17727 |
1.42 |
2009-32 |
57 |
56 |
109 |
81 |
9 |
255 |
17856 |
1.43 |
2009-33 |
54 |
46 |
111 |
124 |
13 |
294 |
19431 |
1.51 |
2009-34 |
53 |
74 |
267 |
99 |
4 |
444 |
19483 |
2.28 |
2009-35 |
51 |
128 |
426 |
99 |
7 |
660 |
20374 |
3.24 |
2009-36 |
50 |
132 |
613 |
177 |
10 |
932 |
20079 |
4.64 |
2009-37 |
50 |
263 |
1101 |
309 |
17 |
1690 |
25056 |
6.74 |
2009-38 |
47 |
184 |
598 |
107 |
13 |
902 |
14102 |
6.40 |
2009-39 |
40 |
213 |
1129 |
446 |
12 |
1800 |
21359 |
8.43 |
National Influenza Activity Map
The current U.S. flu weekly report may be found at http://www.cdc.gov/flu/weekly/fluactivity.htm. *This map indicates geographic spread and does not measure the severity of influenza activity.
For more information on flu surveillance activities in the State of Texas, please visit our main surveillance page.
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