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Influenza Surveillance Update - Week Ending May 18, 2019

Fri, 05/31/2019 - 2:07pm

Marin

Influenza-like illness activity has decreased in Marin.  Positive tests have continued to decline since April 2019.

Influenza-like illness activity 

Flu activity is within expected levels for this time of year. Discharge data from Kaiser San Rafael, Marin General Hospital, and Novato Community Hospital emergency departments showed the percentage of visits associated with influenza-like illness (ILI) was 6.55% during week 20 (May 12-18). See Figure 1 below. 

Influenza Surveillance Update - Week Ending April 6, 2019

Thu, 04/11/2019 - 10:42am

Marin

Influenza-like illness activity has increased in Marin.  Positive tests have remained elevated throughout 2019.

Influenza-like illness activity 

Flu activity remains above expected levels for this time of year. Discharge data from Kaiser San Rafael, Marin General Hospital, and Novato Community Hospital emergency departments showed the percentage of visits associated with influenza-like illness (ILI) was 7.49% during week 14 (March 31 - April 6). See Figure 1 below. 

Influenza Surveillance Update - Week Ending March 23, 2019

Wed, 03/27/2019 - 1:46pm

Marin

Influenza-like illness activity has increased in Marin.  Positive tests have remained elevated throughout 2019.

Influenza-like illness activity 

Discharge data from Kaiser San Rafael, Marin General Hospital, and Novato Community Hospital emergency departments showed the percentage of visits associated with influenza-like illness (ILI) has increased to elevated levels in March and are above expected levels for this time of year.  

Influenza testing

Influenza Surveillance Update, January 2019

Fri, 01/11/2019 - 2:02pm
Marin

Influenza-like illness activity has increased in Marin.  Few laboratory tests were positive in November and early December, however positive tests have increased since mid-December.

Influenza-like illness activity 

Discharge data from Kaiser San Rafael, Marin General Hospital, and Novato Community Hospital emergency departments showed the percentage of visits associated with influenza-like illness (ILI) has increased to moderate levels in December and at expected levels for this time of year.  

Influenza Surveillance Update, February 2018

Thu, 02/01/2018 - 3:52pm
Marin

Influenza-like illness activity has increased in Marin and is currently higher than in past seasons.  Few laboratory tests were positive in November and early December, however positive tests have increased since mid-December.

Influenza-like illness activity 

Influenza Surveillance Update, December 2017

Tue, 12/26/2017 - 4:46pm
Marin

As expected each season, influenza-like illness activity has started to increase in Marin but remains moderate.  Few laboratory tests were positive in November and early December, however preliminary laboratory data show that positive tests have started increasing since mid-December.

Influenza-like illness activity 

Influenza Surveillance Update, Week ending December 31, 2016

Thu, 01/05/2017 - 3:49pm

As expected each season, influenza activity has started to increase in the Bay Area. This week, there have been coordinated county press releases in the region about local influenza activity. The following is a partial Influenza Surveillance Update Report with up-to-date information about recent influenza trends in Marin County. A full Influenza Surveillance Update Report will be released on MarinFlu.org next week (during the week of January 9th).

Influenza Surveillance Update, Week ending May 14, 2016

Wed, 05/25/2016 - 11:59am
Influenza Surveillance Update Survey

Please take five minutes to respond to our Influenza Surveillance Update Survey:  https://www.surveymonkey.com/r/59N9JDC.

Influenza Surveillance Update, Two weeks ending April 16, 2016

Mon, 04/25/2016 - 10:20am
Influenza Surveillance Update

Due to decreasing influenza activity in Marin County, we will be releasing our next and last influenza surveillance update report of the season in one month, during the last week of May.  If you have any questions about influenza activity in the meantime, please reach out to Haylea Hannah at HHannah@marincounty.org or (415) 473-6020.

Influenza Surveillance Update, Two weeks ending April 2, 2016

Tue, 04/12/2016 - 5:56pm
Marin

During weeks 12 (March 20-26) and 13 (March 27-April 2), influenza was still circulating in Marin County.  However, influenza activity is decreasing, with a reduction in both influenza-like illness activity (Figure 1) and the number of positive influenza tests (Figure 2) during weeks 12 and 13.  

Influenza-like illness activity 

Influenza Surveillance Update, Two weeks ending March 19, 2016

Tue, 03/29/2016 - 9:45am
Marin

During weeks 10 (March 6-12) and 11 (March 13-19), influenza was still circulating in Marin County.  Both influenza-like illness activity (Figure 1) and the number of positive influenza tests (Figure 2) were at levels similar to the past few weeks of this influenza season, excluding a one week decline in both measures during week 9.  

Influenza-like illness activity 

Influenza Surveillance Update, Two weeks ending March 5, 2016

Mon, 03/14/2016 - 12:33pm
Marin

During weeks 8 (February 21-27) and 9 (February 28-March 5), influenza was still circulating in Marin County, however, there was a marked reduction in both influenza-like illness activity and the number of positive influenza tests during week 9 (Figure 2). 

Influenza-like illness activity 

Influenza Surveillance Update, Two weeks ending February 20, 2016

Tue, 03/01/2016 - 1:55pm
Marin

During weeks 6 (February 7-13) and 7 (February 14-20), influenza activity increased in Marin County in comparison to recent weeks with elevated influenza-like illness activity (Figure 1) and an increase in the number of positive influenza tests (Figure 2). 

Influenza-like illness activity 

Influenza Surveillance Update, Two weeks ending February 6, 2016

Tue, 02/16/2016 - 5:42pm
Marin

During weeks 4 (January 24-30) and 5 (January 31-February 6), influenza was circulating in Marin County with elevated influenza-like illness activity (Figure 1).  The number of positive influenza tests increased during week 5, leading to an increase in the percent positive (Figure 2). 

Influenza-like illness activity 

Influenza Surveillance Update, Two weeks ending January 23, 2016

Tue, 02/02/2016 - 1:07pm
Severe Influenza Reported Nationally

The CDC released a health advisory urging rapid antiviral treatment of high risk suspect influenza patients without waiting for testing, as H1N1 viruses, which can cause more severe illness, have been more prominent in recent weeks. For more information about the predominant influenza strains observed at the state level during weeks 2 and 3, see the California section below.  Currently, no cases of severe influenza have been reported in Marin.

Influenza Surveillance Update, Two weeks ending January 9, 2016

Tue, 01/19/2016 - 9:58am
Marin

During weeks 52 (December 27-January 2) and 1 (January 3-9), influenza-like illness remained low in Marin.  The number of influenza tests conducted and the number of positive influenza tests have both increased in comparison to the past few weeks of the influenza season, leading to an increase in the percent positive (Figure 2).

Influenza-like illness activity 

Influenza Surveillance Update, Two weeks ending December 26, 2016

Tue, 01/05/2016 - 3:42pm
Marin

During weeks 50 (December 13-19) and 51 (December 20-26), influenza-like illness activity in Marin increased slightly from previous weeks (Figure 1).  However, the percent of positive influenza tests decreased during weeks 50 and 51 in comparison to weeks 48 and 49 (Figure 2).  

Influenza-like illness activity 

Influenza Surveillance Update, Two weeks ending December 12, 2015

Wed, 12/16/2015 - 2:04pm
Marin

During week 48 (November 29-December 5) and week 49 (December 6-12), influenza-like illness remained minimal in Marin.  The number of tests conducted has remained elevated since early November, however, there are still relatively few positive tests.  The percent positive has not increased from prior weeks, which should serve as a reminder to all providers that it is not too late to discuss and offer immunization to our unvaccinated patient population.

Influenza-like illness activity 

Influenza Surveillance Update - Week ending November 28, 2015

Mon, 12/07/2015 - 2:26pm

This is the first influenza surveillance report for the 2015-2016 influenza season.

Marin

During the first eight weeks of the 2015-2016 influenza season (October 4-November 28, 2015), influenza activity in Marin remained minimal and within expected levels for early in the season.  We observed one outbreak in a skilled nursing facility, which contributed to the increase in positive influenza tests in week 44 (Figure 2, week starting date November 1).  

Influenza-like illness activity: 

Influenza Surveillance Update, Two weeks ending March 21

Tue, 03/31/2015 - 3:18pm
Marin

During week 10 (March 8-14) and week 11 (March 15-21), influenza-like illness activity in Marin County was below peak levels, but remained elevated compared to baseline levels (Figure 1).  The number and percent of positive influenza tests continued decreasing, with only two positive tests reported in week 11 (Figure 2).  Due to the substantial reduction in positive influenza tests and anticipated decline in influenza-like illness, this report is the last of the 2014-2015 influenza season.    

Influenza-like illness activity