FluView Week 17: Fatal Swine Variant (H1N1v) Case In Ohio

Credit Wikipedia

 

# 10,048

 

I confess to being a little chagrined that – with our regular flu season essentially over – I didn’t check last week’s FluView report (week 17), else I’d have seen the following notice (h/t Camster on FluTrackers) summarizing the second  swine variant (H1N1v) infection recorded for 2015 (see FluView Wk 3 for 1st report) . 

 

A bit surprisingly, it was not listed in last week’s MMWR table of Notifiable diseases (which I did check).  First the report, then I’ll return with a bit more on swine variant viruses.

 

Novel Influenza A Virus:

One human infection with a novel influenza A virus was reported by the state of Ohio. The person was infected with an influenza A (H1N1) variant (H1N1v) virus and died from complications as a result of the infection. The patient worked at a livestock facility that housed swine but no direct contact with swine was reported in the week prior to illness onset. No ongoing human-to-human transmission has been identified.

Early identification and investigation of human infections with novel influenza A viruses are critical in order to evaluate the extent of the outbreak and possible human-to-human transmission. Additional information on influenza in swine, variant influenza infection in humans, and strategies to interact safely with swine can be found at http://www.cdc.gov/flu/swineflu/index.htm.

 

The CDC describes Swine Variant viruses in their Key Facts FAQ.

 

What is a variant influenza virus?

When an influenza virus that normally circulates in swine (but not people) is detected in a person, it is called a “variant influenza virus.” For example, if a swine origin influenza A H3N2 virus is detected in a person, that virus will be called an “H3N2 variant” virus or “H3N2v” virus.

 

Over the past few years we’ve watched as several swine variant influenza viruses (H1N1v, H1N2v or H3N2v) have made tentative jumps into the human population (see Keeping Our Eyes On The Prize Pig) and each summer the CDC has issued advice on preventing infection at county and state fairs (see Measures to Minimize Influenza Transmission at Swine Exhibitions, 2014).

Of the 374 Swine variant infections detected over the past decade (undoubtedly an undercount given the limited testing), the the vast majority have been of the H3N2v subtype.  Only 18 (5%) were H1N1v, and even less (5) were of the H1N2v variety.

We’ve not seen many reported cases the past couple of years, but during the summer of 2012 more than 300 cases were detected, with Indiana and Ohio accounting for more than 3/4ths of the cases. 

 

Illnesses were usually mild or moderate ( only 1 fatality until now), and infection usually occurred in the summer and fall - associated with attendance of local and state fairs where pigs were being shown.  Of course, some people have contact with swine all year round, and so while uncommon, it isn’t terribly surprising that someone would contract a swine variant virus `out of season’.

 

These swine viruses are important because – unlike many of the avian strains – they belong to the H1, H2, and H3 HA types that have led to all of the known pandemics of the past 130 years.  

 

The progression of human influenza pandemics over the past 130 years has been a fairly unoriginal H2, H3, H1, H2, H3, H1, H1 sequence.

 

While that doesn’t prove that an H5 or an H7 virus couldn’t adapt to humans (or hasn’t in the past), it has led some researchers to wonder whether a non H1, H2, or H3 virus has the `right stuff’ to spark a pandemic (see Are Influenza Pandemic Viruses Members Of An Exclusive Club?).

 
So – while not all that unusual, typically poorly transmitted by humans, and generally producing only mild to moderate illness – we keep a special eye on any swine origin virus that manages to jump to humans. 

 

Two weeks ago, in Waiting For The Next Flu To Drop, we looked at some of these `novel flu contenders’, and with county and state fair season kicking off in some areas next month, I’m sure we’ll be talking about biosecurity measures both for the swine and poultry exhibits frequently over the summer.

FluView Week 9: Influenza Decreases, But Remains Elevated

#9822

 

 

Although the level of influenza across the United States continues to wind down, in some places influenza lingers on, with widespread influenza activity still reported by nine states (Connecticut, Indiana, Maine, Massachusetts, New Hampshire, New Jersey, New York, Oklahoma, and Vermont).

Influenza B, as we often see, is making a late season surge – and unlike with the mismatched H3N2 component of this year’s vaccine – the B  (trivalent & quadrivalent) vaccine components appear a good match.  

 

Roughly 2/3rds of the B viruses in circulation are covered by this year’s trivalent vaccine.  Seven additional pediatric deaths were announced, and the 120 city P&I (Pneumonia & Influenza) mortality rate crept up slightly over the previous week.

Between seeing a flu season heavily dominated by H3N2 – which often affects the elderly more severely than H1N1 – and a greatly reduced Flu Vaccine Effectiveness (VE) due to the `drifted’ H3N2 virus, this has been a particularly harsh flu season for those over the age of 65.

A few excerpts from today’s report follow:

 

 

2014-2015 Influenza Season Week 9 ending March 7, 2015

All data are preliminary and may change as more reports are received.

Synopsis:

During week 9 (March 1-7, 2015), influenza activity continued to decrease, but remained elevated in the United States.

• Viral Surveillance: Of 14,634 specimens tested and reported by U.S. World Health Organization (WHO) and National Respiratory and Enteric Virus Surveillance System (NREVSS) collaborating laboratories during week 9, 1,670 (11.4%) were positive for influenza.
• Pneumonia and Influenza Mortality: The proportion of deaths attributed to pneumonia and influenza (P&I) was above the epidemic threshold.
• Influenza-associated Pediatric Deaths: Seven influenza-associated pediatric deaths were reported.
• Influenza-associated Hospitalizations: A cumulative rate for the season of 55.7 laboratory-confirmed influenza-associated hospitalizations per 100,000 population was reported.
• Outpatient Illness Surveillance: The proportion of outpatient visits for influenza-like illness (ILI) was 2.4%, above the national baseline of 2.0%. Eight regions reported ILI at or above region-specific baseline levels. Puerto Rico and six states experienced high ILI activity; one state experienced moderate ILI activity; 13 states experienced low ILI activity; New York City and 30 states experienced minimal ILI activity; and the District of Columbia had insufficient data.
• Geographic Spread of Influenza: The geographic spread of influenza in nine states was reported as widespread; Guam, Puerto Rico, the U.S. Virgin Islands, and 29 states reported regional activity; 11 states reported local activity; and the District of Columbia and one state reported sporadic activity.

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FluView Week 3: Senior Hospitalizations Soar & H1N1v In Minnesota

 

  *** Correction ***  H1N1v was inadvertently listed as H3N2v in original post – Mea culpa.

 

# 9650

 

Since we’ve got a drifted `H3N2’ virus running rampant across much of the northern hemisphere, an unusually vigorous outbreak of H5N1 in Egypt, our regular winter H7N9 mini-epidemic in China, avian HPAI H5 viruses spreading impressively internationally, and even a pair of imported H7N9 cases in Canada this week  . . .it makes perfect sense that the latest MMWR & FluView would include news of an uncharacteristically out-of-season H1N1v infection in Minnesota as well.

H1N1v is  a swine H1N1 virus - that when it jumps to humans - gets the `variant’ tag.

 

Although telegraphed in yesterday’s MMWR, the following announcement appears in today’s FluView Report.

Novel Influenza A Virus:

One human infection with a novel influenza A virus was reported by the state of Minnesota. The person was infected with an influenza A (H1N1) variant (H1N1v) virus, and has fully recovered from their illness. No ongoing human-to-human transmission has been identified and the case patient reported contact with swine in the week prior to illness onset.

Early identification and investigation of human infections with novel influenza A viruses are critical in order to evaluate the extent of the outbreak and possible human-to-human transmission. Additional information on influenza in swine, variant influenza infection in humans, and strategies to interact safely with swine can be found at http://www.cdc.gov/flu/swineflu/index.htm.

Over the past few years we’ve watched as several swine variant influenza viruses (H1N1v, H1N2v or H3N2v) have made tentative jumps into the human population (see Keeping Our Eyes On The Prize Pig) and each summer the CDC has issued advice on preventing infection at county and state fairs (see Measures to Minimize Influenza Transmission at Swine Exhibitions, 2014).

We’ve not seen many reported cases the past couple of years, but during the summer of 2012 more than 300 cases were detected, with Indiana and Ohio accounting for roughly 80% of the cases. 

 

Illnesses were usually mild or moderate (1 fatality was recorded), and infection usually occurred in the summer and fall and was associated with attendance of local and state fairs where pigs were being shown.  Of course, some people have contact with swine all year round, and so while uncommon, it isn’t terribly surprising that someone would contract H3N2v during the winter.

What is surprising is that it  - like we saw with H7N9 in Canada earlier this week – this novel virus was detected against the background noise of a particularly nasty H3N2 influenza season. 

 

While occasional cases are not particularly alarming,  we keep an eye on these swine variant viruses because research has shown there to be only limited community immunity against them (see CIDRAP: Children & Middle-Aged Most Susceptible To H3N2v).

Of more immediate concern is this year’s seasonal flu activity, which remains brisk across much of the country, although in some states are seeing a drop in cases. 

 

Hospitalization rates for the elderly (65+) are the highest ever recorded since the CDC began tracking that data in 2005, and the CDC continues to remind providers of value of early administration of antiviral medications (see Antiviral Letter to Providers).

 

This from today’s FluView Report.

 

2014-2015 Influenza Season Week 3 ending January 24, 2015

All data are preliminary and may change as more reports are received.

Synopsis:

During week 3 (January 18-24, 2015), influenza activity remained elevated in the United States.

• Viral Surveillance: Of 23,339 specimens tested and reported by U.S. World Health Organization (WHO) and National Respiratory and Enteric Virus Surveillance System (NREVSS) collaborating laboratories during week 3, 4,651 (19.9%) were positive for influenza.
• Novel Influenza A Virus: One human infection with a novel influenza A virus was reported.
• Pneumonia and Influenza Mortality: The proportion of deaths attributed to pneumonia and influenza (P&I) was above the epidemic threshold.
• Influenza-associated Pediatric Deaths: Five influenza-associated pediatric deaths were reported.
• Influenza-associated Hospitalizations: A cumulative rate for the season of 40.5 laboratory-confirmed influenza-associated hospitalizations per 100,000 population was reported.
• Outpatient Illness Surveillance: The proportion of outpatient visits for influenza-like illness (ILI) was 4.4%, above the national baseline of 2.0%. All 10 regions reported ILI at or above region-specific baseline levels. Puerto Rico and 29 states experienced high ILI activity; New York City and seven states experienced moderate ILI activity; six states experienced low ILI activity; eight states experienced minimal ILI activity; and the District of Columbia had insufficient data.
• Geographic Spread of Influenza: The geographic spread of influenza in Puerto Rico and 44 states was reported as widespread; the U.S. Virgin Islands and five states reported regional activity; and the District of Columbia, Guam, and one state reported local activity.

Pneumonia and Influenza (P&I) Mortality Surveillance:

During week 3, 9.1% of all deaths reported through the 122 Cities Mortality Reporting System were due to P&I. This percentage was above the epidemic threshold of 7.1% for week 3.

 

Influenza-Associated Pediatric Mortality:

Five influenza-associated pediatric deaths were reported to CDC during week 3. Four deaths were associated with an influenza A (H3) virus and occurred during weeks 53, 1, 2, and 3 (weeks ending January 3, January 10, January 17, and January 24, 2015, respectively). One death was associated with an influenza A virus for which no subtyping was performed and occurred during week 1.

A total of 61 influenza-associated deaths have been reported during the 2014-2015 season from New York City [1] and 24 states (Arizona [1], Colorado [2], Florida [2], Georgia [1], Indiana [1], Iowa [3], Kansas [2], Kentucky [3], Louisiana [2], Michigan [1], Minnesota [4], Missouri [1], North Carolina [2], Nevada [3], New York [1], Ohio [5], Oklahoma [4], Pennsylvania [1], South Carolina [1], South Dakota [1], Tennessee [4], Texas [7], Virginia [3], and Wisconsin [5]).
Additional data can be found at: http://gis.cdc.gov/GRASP/Fluview/PedFluDeath.html.

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Influenza-Associated Hospitalizations:

Between October 1, 2014 and January 24, 2015, 11,077 laboratory-confirmed influenza-associated hospitalizations were reported. The overall hospitalization rate was 40.5 per 100,000 population. The highest rate of hospitalization was among adults aged ≥65 years (198.4 per 100,000 population), followed by children aged 0-4 years (38.2 per 100,000 population). Among all hospitalizations, 10,690 (96.6%) were associated with influenza A, 290 (2.6%) with influenza B, 29 (0.3%) with influenza A and B co-infection, and 62 (0.5%) had no virus type information. Among those with influenza A subtype information, 3,016 (99.7%) were A(H3N2) virus and nine (0.3%) were A(H1N1)pdm09.

Clinical findings are preliminary and based on 1,729 (15.6%) cases with complete medical chart abstraction. The majority (93.7%) of hospitalized adults had at least one reported underlying medical condition; the most commonly reported were cardiovascular disease, metabolic disorders, and obesity. There were 230 hospitalized children with complete medical chart abstraction, 94 (40.9%) had no identified underlying medical conditions. The most commonly reported underlying medical conditions among pediatric patients were asthma, obesity, neurologic disorders and immune suppression. Among the 173 hospitalized women of childbearing age (15-44 years), 47 were pregnant.

Additional FluSurv-NET data can be found at: http://gis.cdc.gov/GRASP/Fluview/FluHospRates.html and http://gis.cdc.gov/grasp/fluview/FluHospChars.html

(Continue . . .)

 

Despite its reduced effectiveness, the CDC continues to recommend that people get the flu shot – partially because it may provide some modicum of protection against this drifted flu strain, and partly because we often see a wave of Influenza B late in the flu season, and the shot can help protect against that virus.

 

Beyond that, practicing good flu hygiene remains your best strategy for staying well; Staying home when sick, washing your hands, covering your coughs, and disposing of your tissues properly .

FluView Week 2

 

 

# 9621

 

Influenza activity remains elevated across much of the nation, and while some regions have seen some reduction in flu  reports, this week’s CDC FluView report once again shows the P&I (Pneumonia & Influenza) Mortality rate well above the epidemic threshold at 9.1%.

 

Hospitalizations – particularly for those over the age of 65 – have soared to 176.1 per 100,000 – double the maximum hit last year and nearly as high as we saw in the particularly harsh 2012-13 season. Additionally,  11 more pediatric flu-related deaths were reported.

 

Nearly all of the flu in the country is A/H3N2, and roughly 2/3rds of those samples tested continue to be `mismatched’ to this year’s vaccine strain.  With weeks remaining in this year’s flu season, the CDC continues to advise that the Prompt Use of Antivirals is Key this Flu Season.

 

A few excerpts from today’s report.

 

2014-2015 Influenza Season Week 2 ending January 17, 2015

All data are preliminary and may change as more reports are received.

Synopsis:

During week 2 (January 11-17, 2015), influenza activity remained elevated in the United States.

• Viral Surveillance: Of 26,205 specimens tested and reported by U.S. World Health Organization (WHO) and National Respiratory and Enteric Virus Surveillance System (NREVSS) collaborating laboratories during week 2, 5,104 (19.5%) were positive for influenza.
• Pneumonia and Influenza Mortality: The proportion of deaths attributed to pneumonia and influenza (P&I) was above the epidemic threshold.
• Influenza-associated Pediatric Deaths: Eleven influenza-associated pediatric deaths were reported.
• Influenza-associated Hospitalizations: A cumulative rate for the season of 36.3 laboratory-confirmed influenza-associated hospitalizations per 100,000 population was reported.
• Outpatient Illness Surveillance: The proportion of outpatient visits for influenza-like illness (ILI) was 4.5%, above the national baseline of 2.0%. All 10 regions reported ILI at or above region-specific baseline levels. Puerto Rico and 23 states experienced high ILI activity; New York City and 10 states experienced moderate ILI activity; 10 states experienced low ILI activity; seven states experienced minimal ILI activity; and the District of Columbia had insufficient data.
• Geographic Spread of Influenza: The geographic spread of influenza in 44 states was reported as widespread; Guam, Puerto Rico, the U.S. Virgin Islands, and five states reported regional activity; and the District of Columbia and one state reported local activity.

Influenza-Associated Pediatric Mortality:

Eleven influenza-associated pediatric deaths were reported to CDC during week 2. Three deaths were associated with an influenza A (H3) virus and occurred during weeks 51, 53, and 1 (weeks ending December 20, 2014, January 3, and January 10, 2015, respectively). Eight deaths were associated with an influenza A virus for which no subtyping was performed and occurred during weeks 51, 52, 53, 1, and 2 (weeks ending December 20, December 27, 2014, and January 3, January 10, and January 17, 2015, respectively).

A total of 56 influenza-associated deaths have been reported during the 2014-2015 season from New York City [1] and 23 states (Arizona [1], Colorado [2], Florida [2], Georgia [1], Indiana [1], Iowa [2], Kansas [2], Kentucky [3], Louisiana [2], Michigan [1], Minnesota [4], Missouri [1], North Carolina [2], Nevada [2], Ohio [4], Oklahoma [3], Pennsylvania [1], South Carolina [1], South Dakota [1], Tennessee [4], Texas [7], Virginia [3], and Wisconsin [5]).
Additional data can be found at: http://gis.cdc.gov/GRASP/Fluview/PedFluDeath.html.

Influenza-Associated Hospitalizations:

<SNIP>

Between October 1, 2014 and January 17, 2015, 9,926 laboratory-confirmed influenza-associated hospitalizations were reported. The overall hospitalization rate was 36.3 per 100,000 population. The highest rate of hospitalization was among adults aged ≥65 years (176.1 per 100,000 population), followed by children aged 0-4 years (34.5 per 100,000 population). Among all hospitalizations, 9,597 (96.8%) were associated with influenza A, 244 (2.5%) with influenza B, 25 (0.2%) with influenza A and B co-infection, and 52 (0.5%) had no virus type information. Among those with influenza A subtype information, 2,623 (99.7%) were A(H3N2) virus and seven (0.3%) were A(H1N1)pdm09.

Clinical findings are preliminary and based on 1,319 (13.3%) cases with complete medical chart abstraction. The majority (93.9%) of hospitalized adults had at least one reported underlying medical condition; the most commonly reported were cardiovascular disease, metabolic disorders, and obesity. There were 196 hospitalized children with complete medical chart abstraction, 83 (42.3%) had no identified underlying medical conditions. The most commonly reported underlying medical conditions among pediatric patients were asthma, obesity, neurologic disorders, and immune suppression. Among the 146 hospitalized women of childbearing age (15-44 years), 40 were pregnant.

Additional FluSurv-NET data can be found at: http://gis.cdc.gov/GRASP/Fluview/FluHospRates.html and http://gis.cdc.gov/grasp/fluview/FluHospChars.html.

(Continue . . . )

 

Despite its reduced effectiveness, the CDC continues to recommend that people get the flu shot – partially because it may provide some modicum of protection against this drifted flu strain, and partly because we often see a wave of Influenza B late in the flu season, and the shot can help protect against that virus.

Beyond that, practicing good flu hygiene; Staying home when sick, washing your hands, covering your coughs, and disposing of your tissues properly are all important habits to maintain during this flu season.

FluView Week 52

 

# 9533

 

We’ve the final FluView report of 2014, and while surveillance and reporting over the holidays often suffers (or is at least delayed), there’s little doubt that influenza continues to rise and spread across the nation.  Roughly 30% of samples tested by the CDC in week 52 tested positive for influenza –  up from 17% positive rate at the start of December.

 

And as has been the case since the flu season kicked off, samples have been overwhelmingly Influenza A, and of those, almost all H3N2. 

 

The percentage of `drifted’ H3N2 viruses detected – those that differ antigenically from this year’s vaccine – remains roughly 70% (22 of 29 samples tested this week).  Despite the expected reduced effectiveness of this year’s flu shot, the CDC advises there are still benefits to getting the vaccine if you haven’t done so already. 

• There are two other strains (H1N1 & Influenza B) covered by the shot, which may emerge later in the year
• 30% the H3N2 viruses tested so far are still a `match’  to the vaccine strain
• There may still be some degree of cross-protection afforded against this new strain.

There were, regrettably, 6 influenza related pediatric deaths reported this week.

 

The slight `good news’ in this week’s report is that the P&I weekly mortality numbers have softened slightly, dropping below the `epidemic threshold’  set just last week. But given that Pneumonia & Influenza Mortality reporting is usually a `lagging indicator’, and the holidays often impede the flow of reporting, one shouldn’t read too much into this minor drop.

 

Some excerpts from today’s report.

 

2014-2015 Influenza Season Week 52 ending December 27, 2014

All data are preliminary and may change as more reports are received.

Synopsis:

During week 52 (December 21-27, 2014), influenza activity continued to increase in the United States.

• Viral Surveillance: Of 24,001 specimens tested and reported by U.S. World Health Organization (WHO) and National Respiratory and Enteric Virus Surveillance System (NREVSS) collaborating laboratories during week 52, 7,289 (30.4%) were positive for influenza.
• Pneumonia and Influenza Mortality: The proportion of deaths attributed to pneumonia and influenza (P&I) was below the epidemic threshold.
• Influenza-associated Pediatric Deaths: Six influenza-associated pediatric deaths were reported.
• Influenza-associated Hospitalizations: A cumulative rate for the season of 12.6 laboratory-confirmed influenza-associated hospitalizations per 100,000 population was reported.
• Outpatient Illness Surveillance: The proportion of outpatient visits for influenza-like illness (ILI) was 5.9%, above the national baseline of 2.0%. All 10 regions reported ILI at or above region-specific baseline levels. Puerto Rico and 29 states experienced high ILI activity; New York City and six states experienced moderate ILI activity; five states experienced low ILI activity; nine states experienced minimal ILI activity; and the District of Columbia and one state had insufficient data.
• Geographic Spread of Influenza: The geographic spread of influenza in 43 states was reported as widespread; Puerto Rico and six states reported regional activity; one state reported sporadic activity; and the District of Columbia, Guam, and the U.S. Virgin Islands did not report.

 

Influenza Virus Characterization*:

CDC has characterized 334 influenza viruses [10 A(H1N1)pdm09, 268 A(H3N2), and 56 influenza B viruses] collected by U.S. laboratories since October 1, 2014.

Influenza A Virus [278]

• A (H1N1)pdm09 [10]: All 10 H1N1 viruses tested were characterized as A/California/7/2009-like, the influenza A (H1N1) component of the 2014-2015 Northern Hemisphere influenza vaccine.

• A (H3N2) [268]: Eighty-five (31.7%) of the 268 H3N2 viruses tested have been characterized as A/Texas/50/2012-like, the influenza A (H3N2) component of the 2014-2015 Northern Hemisphere influenza vaccine. One hundred eighty-three (68.3%) of the 268 viruses tested showed either reduced titers with antiserum produced against A/Texas/50/2012 or belonged to a genetic group that typically shows reduced titers to A/Texas/50/2012. Among viruses that showed reduced titers with antiserum raised against A/Texas/50/2012, most were antigenically similar to A/Switzerland/9715293/2013, the H3N2 virus selected for the 2015 Southern Hemisphere influenza vaccine. A/Switzerland/9715293/2013 is related to, but antigenically and genetically distinguishable, from the A/Texas/50/2012 vaccine virus. A/Switzerland-like H3N2 viruses were first detected in the United States in small numbers in March of 2014 and began to increase through the spring and summer.

Influenza B Virus [56]

Thirty-nine (70%) of the influenza B viruses tested belong to B/Yamagata/16/88 lineage and the remaining 17 (30%) influenza B viruses tested belong to B/Victoria/02/87 lineage.

• Yamagata Lineage [39]: All 39 B/Yamagata-lineage viruses were characterized as B/Massachusetts/2/2012-like, which is included as an influenza B component of the 2014-2015 Northern Hemisphere trivalent and quadrivalent influenza vaccines.

• Victoria Lineage [17]: Fifteen (88%) of the 17 B/Victoria-lineage viruses were characterized as B/Brisbane/60/2008-like, the virus that is included as an influenza B component of the 2014-2015 Northern Hemisphere quadrivalent influenza vaccine. Two (12%) of the B/Victoria-lineage viruses tested showed reduced titers to B/Brisbane/60/2008.

 

Pneumonia and Influenza (P&I) Mortality Surveillance:

During week 52, 6.8% of all deaths reported through the 122 Cities Mortality Reporting System were due to P&I. This percentage was below the epidemic threshold of 6.9% for week 52.

 

Influenza-Associated Pediatric Mortality:

Six influenza-associated pediatric deaths were reported to CDC during week 52. Three deaths were associated with an influenza A (H3) virus and occurred during weeks 51 and 52 (weeks ending December 20 and December 27, 2014, respectively). Two deaths were associated with an influenza A virus for which no subtyping was performed and occurred during weeks 51 and 52. One death was associated with an influenza virus for which the type was not determined and occurred during week 51.

A total of 21 influenza-associated deaths have been reported during the 2014-2015 season from 11 states (Arizona [1], Colorado [1], Florida [2], Kansas [1], Minnesota [3], North Carolina [2], Nevada [1], Ohio [2], Tennessee [3], Texas [3], and Virginia [2]).

Additional data can be found at: http://gis.cdc.gov/GRASP/Fluview/PedFluDeath.html.

(Continue . . . )

 

Whether you got the shot or not, with people returning back to work and to school after the holidays, it is important to focus on on practicing good flu hygiene.  The CDC suggests:

• Try to avoid close contact with sick people.
• If you are sick with flu-like illness, CDC recommends that you stay home for at least 24 hours after your fever is gone except to get medical care or for other necessities. (Your fever should be gone without the use of a fever-reducing medicine.)
• While sick, limit contact with others as much as possible to keep from infecting them.
• Cover your nose and mouth with a tissue when you cough or sneeze. Throw the tissue in the trash after you use it.
• Wash your hands often with soap and water. If soap and water are not available, use an alcohol-based hand rub.
• Avoid touching your eyes, nose and mouth. Germs spread this way.
• Clean and disinfect surfaces and objects that may be contaminated with germs like the flu.

FluView Week 51

FluView Week 51

# 9510

 

While avian flu in China and Egypt have captured a good deal of our attention, we continue to tread deeper into a difficult H3N2 dominated flu season, with increasing media reports of crowded hospitals and scattered deaths across the nation. 

 

Keeping track of all of this,we have the CDC’s FluView report – normally released on Fridays – but delayed last week due to the mid-week Holidays and was posted this morning.

 

The new `drifted’ H3N2 virus – one that is a poor match for this year’s vaccine strain – continues to show up in surveillance, although unlike last week where all of the samples (n=12) were a `miss’, this week 14 of 30 H3N2 viruses tested match the vaccine.  At this point in the season, roughly 2/3rds of the H3N2 viruses tested are of the new strain.

This week, for the first time in this year’s flu season, the P&I (Pneumonia & Influenza) Mortality level was at the epidemic threshold. Nearly all of the flu being reported is influenza A, and nearly all of those cases are H3N2, which often produces a more severe flu season than does H1N1. 

 

Some excerpts from this weeks report include:

 

2014-2015 Influenza Season Week 51 ending December 20, 2014

All data are preliminary and may change as more reports are received.

Synopsis:

During week 51 (December 14-20, 2014), influenza activity continued to increase in the United States.

• Viral Surveillance: Of 21,858 specimens tested and reported by U.S. World Health Organization (WHO) and National Respiratory and Enteric Virus Surveillance System (NREVSS) collaborating laboratories during week 51, 6,152 (28.1%) were positive for influenza.
• Pneumonia and Influenza Mortality: The proportion of deaths attributed to pneumonia and influenza (P&I) was at the epidemic threshold.
• Influenza-associated Pediatric Deaths: Four influenza-associated pediatric deaths were reported.
• Influenza-associated Hospitalizations: A cumulative rate for the season of 9.7 laboratory-confirmed influenza-associated hospitalizations per 100,000 population was reported.
• Outpatient Illness Surveillance: The proportion of outpatient visits for influenza-like illness (ILI) was 5.5%, above the national baseline of 2.0%. All 10 regions reported ILI at or above region-specific baseline levels. Puerto Rico and 22 states experienced high ILI activity; six states experienced moderate ILI activity; New York City and eight states experienced low ILI activity; 14 states experienced minimal ILI activity; and the District of Columbia had insufficient data.
• Geographic Spread of Influenza: The geographic spread of influenza in 36 states was reported as widespread; Guam, Puerto Rico, and 10 states reported regional activity; the District of Columbia, the U.S. Virgin Islands, and two states reported local activity; and two states reported sporadic activity.

Influenza Virus Characterization*:

CDC has characterized 305 influenza viruses [10 A(H1N1)pdm09, 239 A(H3N2), and 56 influenza B viruses] collected by U.S. laboratories since October 1, 2014.

Influenza A Virus [249]

• A (H1N1)pdm09 [10]: All 10 H1N1 viruses tested were characterized as A/California/7/2009-like, the influenza A (H1N1) component of the 2014-2015 Northern Hemisphere influenza vaccine.

• A (H3N2) [239]: Seventy-eight (32.6%) of the 239 H3N2 viruses tested have been characterized as A/Texas/50/2012-like, the influenza A (H3N2) component of the 2014-2015 Northern Hemisphere influenza vaccine. One hundred sixty-one (67.4%) of the 239 viruses tested showed either reduced titers with antiserum produced against A/Texas/50/2012 or belonged to a genetic group that typically shows reduced titers to A/Texas/50/2012. Among viruses that showed reduced titers with antiserum raised against A/Texas/50/2012, most were antigenically similar to A/Switzerland/9715293/2013, the H3N2 virus selected for the 2015 Southern Hemisphere influenza vaccine. A/Switzerland/9715293/2013 is related to, but antigenically and genetically distinguishable, from the A/Texas/50/2012 vaccine virus. A/Switzerland-like H3N2 viruses were first detected in the United States in small numbers in March of 2014 and began to increase through the spring and summer.

Influenza B Virus [56]

Thirty-nine (70%) of the influenza B viruses tested belong to B/Yamagata/16/88 lineage and the remaining 17 (30%) influenza B viruses tested belong to B/Victoria/02/87 lineage.

• Yamagata Lineage [39]: All 39 B/Yamagata-lineage viruses were characterized as B/Massachusetts/2/2012-like, which is included as an influenza B component of the 2014-2015 Northern Hemisphere trivalent and quadrivalent influenza vaccines.

• Victoria Lineage [17]: Fifteen (88%) of the 17 B/Victoria-lineage viruses were characterized as B/Brisbane/60/2008-like, the virus that is included as an influenza B component of the 2014-2015 Northern Hemisphere quadrivalent influenza vaccine. Two (12%) of the B/Victoria-lineage viruses tested showed reduced titers to B/Brisbane/60/2008.

  

Influenza-Associated Pediatric Mortality:

Four influenza-associated pediatric deaths were reported to CDC during week 51. Three deaths were associated with an influenza A (H3) virus and occurred during weeks 49 and 50 (weeks ending December 6 and December 13, 2014, respectively). One death was associated with an influenza B virus and occurred during week 51 (week ending December 20, 2014).

A total of 15 influenza-associated deaths have been reported during the 2014-2015 season from nine states (Arizona [1], Colorado [1], Florida [2], Minnesota [2], North Carolina [2], Nevada [1], Ohio [2], Texas [3], and Virginia [1]).
Additional data can be found at: http://gis.cdc.gov/GRASP/Fluview/PedFluDeath.html.

 (Continue . . . )

 

Whether you got the shot or not, with holiday gatherings upon us our focus now should be on practicing good flu hygiene. 

The CDC suggests:

• Try to avoid close contact with sick people.
• If you are sick with flu-like illness, CDC recommends that you stay home for at least 24 hours after your fever is gone except to get medical care or for other necessities. (Your fever should be gone without the use of a fever-reducing medicine.)
• While sick, limit contact with others as much as possible to keep from infecting them.
• Cover your nose and mouth with a tissue when you cough or sneeze. Throw the tissue in the trash after you use it.
• Wash your hands often with soap and water. If soap and water are not available, use an alcohol-based hand rub.
• Avoid touching your eyes, nose and mouth. Germs spread this way.
• Clean and disinfect surfaces and objects that may be contaminated with germs like the flu.

FluView Week 50

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Earlier this week, in It’s Beginning To Look A Lot Like . . . Flu Season, I wrote about the recent media reports on school absences (and some closures) due to influenza.  You’ll also find some advice in that blog on the home treatment of flu, and when to seek medical care, from the CDC.

 

Although the CDC numbers, and maps, lag about a week behind current conditions - they clearly show that this year’s flu season is well underway across much of the middle of the nation.  

 

With an overwhelmingly H3N2 dominant flu season so far – and a `mismatched’ strain reducing this year’s vaccine’s efficiency – the CDC has warned Early Data Suggests Potentially Severe Flu Season ahead.  While the numbers don’t show us there yet – we are still below the `epidemic threshold’ for P&I Mortality – we are seeing steady week-to-week increases in flu activity.

 

Some excerpts from this week’s FluView report, then I’ll be back with a footnote.

 

2014-2015 Influenza Season Week 50 ending December 13, 2014

All data are preliminary and may change as more reports are received.

Synopsis:

During week 50 (December 7-13, 2014), influenza activity continued to increase in the United States.

• Viral Surveillance:Of 20,064 specimens tested and reported by U.S. World Health Organization (WHO) and National Respiratory and Enteric Virus Surveillance System (NREVSS) collaborating laboratories during week 50, 5,200 (25.9%) were positive for influenza.
• Pneumonia and Influenza Mortality: The proportion of deaths attributed to pneumonia and influenza (P&I) was below the epidemic threshold.
• Influenza-associated Pediatric Deaths:Four influenza-associated pediatric deaths were reported.
• Influenza-associated Hospitalizations: A cumulative rate for the season of 6.2 laboratory-confirmed influenza-associated hospitalizations per 100,000 population was reported.
• Outpatient Illness Surveillance: The proportion of outpatient visits for influenza-like illness (ILI) was 3.7%, above the national baseline of 2.0%. Nine of 10 regions reported ILI at or above region-specific baseline levels. Puerto Rico and 13 states experienced high ILI activity; six states experienced moderate ILI activity; New York City and five states experienced low ILI activity; 26 states experienced minimal ILI activity; and the District of Columbia had insufficient data.
• Geographic Spread of Influenza: The geographic spread of influenza in Guam and 29 states was reported as widespread; Puerto Rico and 14 states reported regional activity; the District of Columbia, the U.S. Virgin Islands and five states reported local activity; and two states reported sporadic activity.

 

Influenza Virus Characterization*:

CDC has characterized 248 influenza viruses [10 A (H1N1)pdm09, 209 A (H3N2), and 29 influenza B viruses] collected by U.S. laboratories since October 1, 2014.

Influenza A Virus [219]

• A (H1N1)pdm09 [10]: All 10 H1N1 viruses tested were characterized as A/California/7/2009-like, the influenza A (H1N1) component of the 2014-2015 Northern Hemisphere influenza vaccine.

• A (H3N2) [209]: Sixty-four (30.6%) of the 209 H3N2 viruses tested have been characterized as A/Texas/50/2012-like, the influenza A (H3N2) component of the 2014-2015 Northern Hemisphere influenza vaccine. One hundred forty-five (69.4%) of the 209 viruses tested showed either reduced titers with antiserum produced against A/Texas/50/2012 or belonged to a genetic group that typically shows reduced titers to A/Texas/50/2012. Among viruses that showed reduced titers with antiserum raised against A/Texas/50/2012, most were antigenically similar to A/Switzerland/9715293/2013, the H3N2 virus selected for the 2015 Southern Hemisphere influenza vaccine. A/Switzerland/9715293/2013 is related to, but antigenically and genetically distinguishable, from the A/Texas/50/2012 vaccine virus. A/Switzerland-like H3N2 viruses were first detected in the United States in small numbers in March of 2014 and began to increase through the spring and summer.

<SNIP>

Influenza-Associated Pediatric Mortality:

Four influenza-associated pediatric deaths were reported to CDC during week 50. Two deaths were associated with an influenza A (H3) virus and occurred during week 49 (week ending December 6, 2014). One death was associated with an influenza A virus for which no subtyping was performed and occurred during week 50 (week ending December 13, 2014), and one death was associated with an influenza B virus and occurred during week 49.

A total of 11 influenza-associated deaths have been reported during the 2014-2015 season from six states (Florida [2], Minnesota [2], North Carolina [2], Nevada [1], Ohio [2], and Texas [2]).
Additional data can be found at: http://gis.cdc.gov/GRASP/Fluview/PedFluDeath.html.

(Continue . . .)

If you are looking for good news, none of the viruses this season have tested as being resistant to our two main antiviral drugs – Oseltamivir and Zanamivir. 

 

This time last year, we were seeing nearly 2% of viruses showing signs of resistance.

While expected, and on a less positive note, the percentage of `drifted’ H3N2 viruses continues to climb, with apparently none of the (admittedly small number) of H3N2 viruses tested last week (n=12) matching the vaccine strain.  In the week 49 FluView, of 84 viruses sequenced, less than 20% were a match.

 

As we often see Influenza B become more dominant towards the end of the flu season, this year’s flu shot may still offer you some welcome protection next spring, and the CDC suggests it might still provide some protection against this drifted strain. 

 

For now, whether you got the shot or not, with holiday gatherings upon us our focus should be on practicing good flu hygiene.  The CDC suggests:

• Try to avoid close contact with sick people.
• If you are sick with flu-like illness, CDC recommends that you stay home for at least 24 hours after your fever is gone except to get medical care or for other necessities. (Your fever should be gone without the use of a fever-reducing medicine.)
• While sick, limit contact with others as much as possible to keep from infecting them.
• Cover your nose and mouth with a tissue when you cough or sneeze. Throw the tissue in the trash after you use it.
• Wash your hands often with soap and water. If soap and water are not available, use an alcohol-based hand rub.
• Avoid touching your eyes, nose and mouth. Germs spread this way.
• Clean and disinfect surfaces and objects that may be contaminated with germs like the flu.

FluView Week 48

 

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Although the CDC has warned that  Early Data Suggests a Potentially Severe Flu Season ahead, and there are growing concerns of an H3N2 vaccine component `mismatch’ (see CDC HAN Advisory On `Drifted’ H3N2 Seasonal Flu Virus), North America’s flu season is just really getting started. 

The latest FluView report shows modest increases in flu activity over the previous week, along with a rising percentage of `antigenically mismatched’ H3N2 virus detections (last week 52%, this week 58%). 

Influenza virus detections are nearly 94% Influenza A, and of those tested, they are overwhelmingly H3N2 viruses. For now, we remain well below the P&I (Pneumonia & Influenza) epidemic threshold.

 

Despite the possibility of seeing a less effective flu vaccine this year, the CDC continues to recommend that everyone get the shot, as it protects against more than just H3N2 subtype, and it may also provide some protection even against the drifted strain. 

 

The MMWR reminds us, next week is National Influenza Vaccination Week — December 7–13, 2014. 

 

As it takes a couple of weeks for a flu shot to reach its maximum level of protectiveness, it is better to get it before influenza starts circulating in your community.  

And this advice on the value of antiviral treatment from yesterday’s press release from the CDC if you do get the flu:

Those at high risk from influenza include children younger than 5 years (especially those younger than 2 years); adults 65 years and older; pregnant women; and people with certain chronic health conditions such as asthma, diabetes, heart or lung disease, and kidney disease.

CDC recommends that people at high risk check with their doctor or other health care professional promptly if they get flu symptoms.

Some highlights from this week’s report include.

 

Weekly U.S. Influenza Surveillance Report

2014-2015 Influenza Season Week 48 ending November 29, 2014

Full report also available as PDF

Synopsis:

During week 48 (November 23-29, 2014), influenza activity increased in the United States.

• Viral Surveillance: Of 13,398 specimens tested and reported by U.S. World Health Organization (WHO) and National Respiratory and Enteric Virus Surveillance System (NREVSS) collaborating laboratories during week 48, 2,274 (17.0%) were positive for influenza.
• Pneumonia and Influenza Mortality: The proportion of deaths attributed to pneumonia and influenza (P&I) was below the epidemic threshold.
• Influenza-associated Pediatric Deaths: No influenza-associated pediatric deaths were reported.
• Influenza-associated Hospitalizations: A cumulative rate for the season of 1.8 laboratory-confirmed influenza-associated hospitalizations per 100,000 population was reported.
• Outpatient Illness Surveillance:The proportion of outpatient visits for influenza-like illness (ILI) was 2.6%, above the national baseline of 2.0%. Eight of 10 regions reported ILI at or above region-specific baseline levels. Puerto Rico and six states experienced high ILI activity; one state experienced moderate ILI activity; five states experienced low ILI activity; New York City and 38 states experienced minimal ILI activity; and the District of Columbia had insufficient data.
• Geographic Spread of Influenza: The geographic spread of influenza in Puerto Rico and six states was reported as widespread; 14 states reported regional activity; the U.S. Virgin Islands and 19 states reported local activity; the District of Columbia and 11 states reported sporadic activity; and Guam did not report.

<SNIP>

<SNIP>

A (H3N2) [114]: Forty-eight (42%) of the 114 H3N2 viruses tested have been characterized as A/Texas/50/2012-like, the influenza A (H3N2) component of the 2014-2015 Northern Hemisphere influenza vaccine. Sixty-six (58%) of the 114 viruses tested showed either reduced titers with antiserum produced against A/Texas/50/2012 or belonged to a genetic group that typically shows reduced titers to A/Texas/50/2012. Among viruses that showed reduced titers with antiserum raised against A/Texas/50/2012, most were antigenically similar to A/Switzerland/9715293/2013, the H3N2 virus selected for the 2015 Southern Hemisphere influenza vaccine. A/Switzerland/9715293/2013 is related to, but antigenically and genetically distinguishable, from the A/Texas/50/2012 vaccine virus. A/Switzerland-like H3N2 viruses were first detected in the United States in small numbers in March of 2014 and began to increase through the spring and summer.

<SNIP>

During week 48, the following ILI activity levels were experienced:

• Puerto Rico and six states (Alabama, Florida, Georgia, Louisiana, Mississippi, and Texas) experienced high ILI activity.
• One state (Illinois) experienced moderate ILI activity.
• Five states (Kansas, Missouri, Nevada, Utah, and Virginia) experienced low ILI activity.
• New York City and 38 states (Alaska, Arizona, Arkansas, California, Colorado, Connecticut, Delaware, Hawaii, Idaho, Indiana, Iowa, Kentucky, Maine, Maryland, Massachusetts, Michigan, Minnesota, Montana, Nebraska, New Hampshire, New Jersey, New Mexico, New York, North Carolina, North Dakota, Ohio, Oklahoma, Oregon, Pennsylvania, Rhode Island, South Carolina, South Dakota, Tennessee, Vermont, Washington, West Virginia, Wisconsin, and Wyoming) experienced minimal ILI activity.
• Data were insufficient to calculate an ILI activity level from the District of Columbia.

CDC FluView Week 3

Credit CDC FluView

 

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Flu season remains in full swing in the Northern Hemisphere, with the pH1N1 virus causing the bulk of the misery across the United States.  Unlike seasonal H3N2 – which usually hits those over the age of 65 the hardest – pH1N1 often severely impacts younger age groups.

 

And the evidence thus far is that adults under the age of 65 are being hit particularly hard by this year’s flu season.

 

 

2013-2014 Influenza Season Week 3 ending January 18, 2014

All data are preliminary and may change as more reports are received.

Synopsis:

During week 3 (January 12-18, 2014), influenza activity remained high in the United States.

• Viral Surveillance: Of 12,108 specimens tested and reported during week 3 by U.S. World Health Organization (WHO) and National Respiratory and Enteric Virus Surveillance System (NREVSS) collaborating laboratories, 2,793 (23.1%) were positive for influenza.
• Pneumonia and Influenza Mortality: The proportion of deaths attributed to pneumonia and influenza (P&I) was above the epidemic threshold.
• Influenza-Associated Pediatric Deaths: Eight influenza-associated pediatric deaths were reported.
• Influenza-associated Hospitalizations: A season-cumulative rate of 17.0 laboratory-confirmed influenza-associated hospitalizations per 100,000 population was reported.
• Outpatient Illness Surveillance: The proportion of outpatient visits for influenza-like illness (ILI) was 3.4%, above the national baseline of 2.0%. All 10 regions reported ILI above region-specific baseline levels. Thirteen states experienced high ILI activity; seven states and New York City experienced moderate ILI activity; 15 states experienced low ILI activity; 15 states experienced minimal ILI activity, and the District of Columbia had insufficient data.
• Geographic Spread of Influenza: The geographic spread of influenza in 41 states was reported as widespread; eight states and Puerto Rico reported regional influenza activity; the District of Columbia reported local influenza activity; one state and Guam reported sporadic influenza activity, and the U.S. Virgin Islands reported no influenza activity.

A description of surveillance methods is available at: http://www.cdc.gov/flu/weekly/overview.htm

 

A few graphs from today’s report, to help compare this year to the last couple:

 

For the second week in a row the P&I mortality rate has been above the epidemic threshold.  It is at a hefty 8.1% in week three, but less than the near-record 9.8% in week three a year ago.

 

Pneumonia and Influenza (P&I) Mortality Surveillance

During week 3, 8.1% of all deaths reported through the 122 Cities Mortality Reporting System were due to P&I. This percentage was above the epidemic threshold of 7.2% for week 3.

 

Pediatric deaths, meanwhile, are lower than this time last year, and considerably below the numbers we saw in the 2009-10, and 2010-11 flu seasons.  These are, however, often lagging indicators and we often get `caught up’ with cases later in the season.

 

 

 

And one last graph shows hospitalizations by age cohorts with confirmed influenza, and those over the age of 50, and under the age of 4, make up the majority of these cases while those aged 5-49 are the least impacted.  

Last year, the hospitalization rate for those aged > 65 in week three was triple that of what we are seeing this season.

 

While some states are reporting a decrease in influenza activity, others continue to rise, and we are apt to see significant flu activity for weeks to come.

 

Regardless of the strain of flu in circulation, you are much better off avoiding infection rather than treating it. So while it may only provide moderate protection, getting the flu shot each year is cheap insurance.

 

That, and following good flu hygiene practices (covering coughs, washing hands frequently, staying home when sick, avoiding close contact with those who are sick), are your best defense against our yearly flu epidemic.

FluView Week 2: The Shifting Demographics Of Seasonal Flu

 

 
FluView Week 2

 

 

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Although seasonal flu comes around each year, every flu season has a distinct `personality’ as the various flu strains struggle for dominance, and accumulated antigenic drift aids in their ability to evade community immunity. 

 

Some flu seasons are relatively mild (like 2011-2012), while others are more severe (like 2012-2013).  And the preferential target of these viruses shift from year-to-year as well, something we saw during 2009 H1N1 pandemic, which had its greatest affect on those under the age of 65.

 

This year – for the first time in 3 years – we are seeing the pH1N1 virus (introduced in the 2009 pandemic, but now a seasonal strain) the major player in North America, and as that strain tends to hit younger people harder.  As a result we’ve seen a good deal of media coverage of young adults hospitalized and some even dying from the flu. 

Credit FluView Week 2

The above chart shows how much less this year’s flu is affecting those over 65 (green) than it did last year, with those aged between 18 and 64 representing the bulk of this year’s hospitalizations.

 

Despite this distressing age shift towards younger patients, the absolute numbers for week 2 of this year are less severe than they were this time last year.

 

First, a brief summary of week 2’s activities from the CDC, then I’ll have some side-by-side comparisons of this week vs 1 years ago.

 

2013-2014 Influenza Season Week 2 ending January 11, 2014

All data are preliminary and may change as more reports are received.

Synopsis:

During week 2 (January 5-11, 2014), influenza activity remained high in the United States.

• Viral Surveillance: Of 10,841 specimens tested and reported during week 2 by U.S. World Health Organization (WHO) and National Respiratory and Enteric Virus Surveillance System (NREVSS) collaborating laboratories, 2,721 (25.1%) were positive for influenza.
• Pneumonia and Influenza Mortality: The proportion of deaths attributed to pneumonia and influenza (P&I) was above the epidemic threshold.
• Influenza-Associated Pediatric Deaths: Ten influenza-associated pediatric deaths were reported.
• Influenza-associated Hospitalizations: A cumulative rate for the season of 13.8 laboratory-confirmed influenza-associated hospitalizations per 100,000 population was reported.
• Outpatient Illness Surveillance: The proportion of outpatient visits for influenza-like illness (ILI) was 3.6%, above the national baseline of 2.0%. All 10 regions reported ILI above region-specific baseline levels. Fourteen states experienced high ILI activity; 12 states experienced moderate ILI activity; eight states and New York City experienced low ILI activity; 16 states experienced minimal ILI activity, and the District of Columbia had insufficient data.
• Geographic Spread of Influenza: The geographic spread of influenza in 40 states was reported as widespread; nine states and Guam reported regional influenza activity; the District of Columbia and Puerto Rico reported local influenza activity; one state reported sporadic influenza activity, and the U.S. Virgin Islands did not report.

With the caveat that different flu seasons peak at different times, and that there may be a good deal more flu ahead before the end of spring, I’ve compared this year’s flu season through week two with last year’s in the charts below.

 

The P&I Mortality rate has – for the first time this flu season – exceeded the epidemic threshold.  It is, however, considerably lower than it was this time last year (and last year reached a 10 year peak in late January).

 

 

Pediatric deaths are often slow in being reported, and right now, the 2014 season is lagging only slightly behind last year’s number for week 2.  In an average year we generally see around 75-125 pediatric deaths reported.

The most dramatic side-by-side comparisons comes from hospitalizations from influenza by age group. 

 

While those under the age of 65 are seeing roughly the same sort of numbers we saw in 2013, those over the age of 65 are dramatically lower than from last year’s flu season.

 

The take-away from all of this is that influenza is not a trivial illness, and even during an average year, it can claim thousands of lives.  Some years – like this year – we see younger people more affected.  We won’t know how this year’s flu season will stack up against previous years until the season is over, and the number are tallied.  

 

Regardless of the strain of flu in circulation, you are much better off avoiding infection rather than treating it. So while it may only provide moderate protection, getting the flu shot each year is cheap insurance. 

 

That, and following good flu hygiene practices (covering coughs, washing hands frequently, staying home when sick, avoiding close contact with those who are sick),  are your best defense against our yearly flu epidemic.