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2017/18 Influenza Season data

 
  Did you know it is estimated that an average of 200K people are hospitalized due to flu-related complications?
 

 

The Pennsylvania Department of Health (PADOH) monitors influenza activity throughout the year but ramps up surveillance activities in the fall and winter. The official influenza surveillance season starts with the 40th week of the year (typically around the beginning of October) and ends on the 20th week of the following year (in May). For the 2017-2018 season, the influenza surveillance season began on Oct. 1, 2017, and will run through May 19, 2017. Updated influenza activity data will be posted on this web page every Tuesday throughout the influenza surveillance season. These updates will provide a summary on:

1. When and where influenza activity is occurring;
2. Current trends in influenza as compared to previous seasons; and
3. What types and subtypes of influenza viruses are currently circulating. 

It is important to note that the influenza case counts presented on this page are restricted to only those cases that have had a positive laboratory test for flu (by rapid test, DFA, PCR or culture) reported to the PADOH. These case counts represent only a fraction of the actual burden of illness due to influenza occurring in the commonwealth at any given time. This is because most persons with influenza do not go to the doctor or are not tested or reported. Influenza spread and severity varies widely from season to season. It is estimated that five to 20 percent (600,000 to 2,400,000) of Pennsylvanians get the flu each year, and 120 to 2,000 die from complications of influenza.

 
Flu Activity Code: Local (week 49 ending December 9, 2017)

*The flu activity code is a characterization of the geographic spread of influenza in Pennsylvania. It does not indicate how severe the influenza season is. Rather, it indicates how much of Pennsylvania is experiencing influenza activity. The level of activity is classified based on CDC definitions below, which are used by all 50 states to characterize influenza activity.

 
​No Activity No laboratory-confirmed cases of influenza and no reported increase in the number of cases of ILI.

SPORADIC

Small numbers of laboratory-confirmed influenza cases or a single laboratory-confirmed influenza outbreak has been reported, but there is no increase in cases of ILI
  LOCAL
​Outbreaks of influenza or increases in ILI cases and recent laboratory-confirmed influenza in a single region of the state
REGIONAL
​Outbreaks of influenza or increases in ILI and recent laboratory confirmed influenza in at least two but less than half the regions of the state, with recent laboratory evidence of influenza in those regions
WIDESPREAD

Outbreaks of influenza or increases in ILI cases and recent laboratory-confirmed influenza in at least half the regions of the state, with recent laboratory evidence of influenza in the state

 Influenza surveillance data presented below reflect influenza activity during the time period referred to above. Data may change from week to week as numbers are adjusted for late reporting, misclassification of cases, and errors in classifying county or state of residence.

 
PENNSYLVANIA WEEKLY INFLUENZA REPORT
 
Summary:
- Laboratory, hospital emergency department, and sentinel medical provider data all indicate that the flu activity is increasing.
- Flu activity for MMWR week 49 has increased in all the state regions and highest activity has been in the southeast region.
- Pennsylvania’s current influenza activity code is "LOCAL"
- No influenza associated death has been reported  during week 49 and total number of reported influenza associated deaths is one, season to date.  
 
Confirmed influenza laboratory tests recived by PA DOH surveillance 

Table 1. Influenza Cases (positive by rapid test, PCR, or culture) Reported in Pennsylvania, 10/01/17 to 12/9/17 (n=1472) - Cases by County and Influenza Type*    
 
County Influenza Type TOTAL
A B U**
ADAMS 19 0 0 19
ALLEGHENY 79 11 5 95
ARMSTRONG 3 1 0 4
BEAVER 10 7 0 17
BEDFORD 2 0 0 2
BERKS 220 6 0 226
BLAIR 8 0 0 8
BRADFORD 3 1 0 4
BUCKS 43 9 0 52
BUTLER 19 6 0 25
CAMBRIA 11 2 0 13
CAMERON 2 1 0 3
CARBON 8 2 0 10
CENTRE 10 6 0 16
CHESTER 32 9 0 41
CLARION 0 1 0 1
CLEARFIELD 13 2 0 15
COLUMBIA 3 0 0 3
CRAWFORD 5 7 0 12
CUMBERLAND 41 6 0 47
DAUPHIN 31 2 0 33
DELAWARE 76 13 0 89
ELK 13 5 0 18
ERIE 16 4 0 20
FAYETTE 15 3 0 18
FOREST 2 0 0 2
FRANKLIN 4 2 0 6
FULTON 1 1 0 2
GREENE 3 2 0 5
HUNTINGDON 4 0 0 4
INDIANA 7 3 0 10
JEFFERSON 7 2 0 9
JUNIATA 1 0 0 1
LACKAWANNA 7 3 0 10
LANCASTER 23 9 0 32
LAWRENCE 3 0 0 3
LEBANON 22 2 0 24
LEHIGH 26 14 0 40
LUZERNE 14 3 0 17
LYCOMING 4 0 0 4
MCKEAN 1 1 0 2
MERCER 6 1 0 7
MIFFLIN 2 0 0 2
MONROE 11 6 0 17
MONTGOMERY 63 17 2 82
MONTOUR 1 1 0 2
NORTHAMPTON 64 50 0 114
NORTHUMBERLAND 5 1 0 6
PERRY 3 0 0 3
PHILADELPHIA 33 13 0 46
PIKE 1 1 0 2
POTTER 5 7 0 12
SCHUYLKILL 26 1 0 27
SNYDER 5 1 0 6
SOMERSET 4 3 0 7
SUSQUEHANNA 2 1 0 3
TIOGA 3 2 0 5
UNION 3 0 0 3
VENANGO 2 0 0 2
WARREN 2 0 0 2
WASHINGTON 53 1 0 54
WAYNE 3 2 0 5
WESTMORELAND 33 6 1 40
WYOMING 2 0 0 2
YORK 54 7 0 61
All 1197 267 8 1472
  * Influenza counts are provisional and may change as more information is received.
**Test results may identify influenza Type A, influenza Type B, or influenza without specifying Type A or B. Some tests only give a positive or negative result and can-not identify influenza type.
 
 
Figure 1. Number of Pa. Influenza Cases by Week of First Report 
 

 Figure 2: Comparison of PA-NEDSS Influenza Cases (All Types) in Current Season to the Seven Previous Seasons
       
                                        
 Figure 3: Season-to-date Influenza Sub-Typing Results From State Public Health Lab (n=46) 
 
 

Table 2: Season-To-Date Influenza-Associated Deaths by Age
 
 
Age​ Influenza associated Death​
0-18 0
19-49 0
50-64 1
65 + 0
All​ 1
 
 

  Syndromic surveillance

The Pennsylvania Department of Health’s syndromic surveillance system receives data on visits to emergency departments (EDs) from most hospitals in the state.  The system looks at the reason for visiting the ED and determines if ED visits were likely due to influenza-like illness (ILI). The graph displays ED visits due to ILI as a percentage of total ED visits. This provides yet another way for the Department of Health to monitor influenza and ILI in the state. 

 Figure 4: season-to-date Influenza-Like Illness (ILI) Emergency Visits


Figure 5: season-to-date Influenza-Like Illness (ILI) Emergency Visits by community health districts  


Figure 6: season-to-date Influenza-Like Illness (ILI) Emergency Visits by age groups



 

World Health Organization (WHO) and National Respiratory & Enteric Virus Surveillance System (NREVSS) Collaborating Laboratories
 
Thirteen clinical virology laboratories in Pa.are WHO and/or NREVSS collaborating laboratories for influenza surveillance.
These labs report weekly the number of respiratory specimens tested and the number positive for influenza types A and B to CDC. Some labs also report the influenza A subtype (H1 or H3) and influenza B lineage (Victoria or Yamagata). Because denominator data is provided, the weekly percentage of specimens testing positive for influenza is calculated.
 
Figure 7: Influenza Test Results Reported to the National Respiratory and Enteric Virus Surveillance System (NREVSS) Select Pennsylvania Laboratories, Season to date