Posts Tagged ‘H3N2’

Influenza Vaccine Season Blows In

September 30th, 2013

It’s almost that time of year… flu season.  Flu shots have arrived and are already in many pharmacies and doctor’s offices, meaning you can already get vaccinated before the flu hits this season.  There’s a wide array of influenza vaccine choices these days – more than ever.  

The nasal spray is approved for healthy, non-pregnant people between the ages of 2 and 49 years old. The shot is approved for most people 6 months and older. There’s also a special high-dose shot for folks 65+ that gives better protection by improving immune response.  This year there are even 2 types of flu vaccines aren’t grown in chicken eggs- allowing even people with egg allergies to be vaccinated this year. 

In past years, flu vaccines have always provided protection against 3 flu strains, 2 influenza A strains and one influenza B strain.  For the first time this year, 4 of the licensed flu vaccines will protect against 4 different flu strains-  two “A” strains and 2 “B” strains.  This year’s (three-strain) vaccines will contain the pandemic and H3N2 strains as well as a brand-new B strain. 

The flu season in the Southern Hemisphere peaked in mid-July and is winding down. Central America, the Caribbean, South America and South Africa and Australia and New Zealand have all been seeing influenza strains that are included in this year’s US vaccines- meaning that this year’s vaccines will likely be a good match for what starts going around when flu season gets going. 

The flu spreads from person to person through droplets made when people sick with flu cough, sneeze or talk. It can give you a fever, cough, sore throat, muscle aches, and make you really tired among other things. That’s why it’s so important to get vaccinated every year to protect yourself and those around you from this bad bug.

Next Season’s Influenza Vaccine

March 5th, 2013

Just as our influenza season winds down (and it is), it’s time to plan for the next one.  Every February the World Health Organization convenes a panel of experts to look at the most current data on the circulating flu strains from around the world and makes recommendations for the next season’s Northern Hemisphere flu vaccine.  At this week’s meeting in Geneva, the group recommended changing a B component of the vaccine, but sticking with the A/H3N2 and A/H1N1 components for next year. 

It may seem too early to be thinking about next year’s flu vaccine, but planning in February allows time for vaccine companies to grow the viruses and process the vaccine. The vaccine-making process still takes about 6 months… so it’s important to start as early as possible to ensure that vaccine is available for the start of the next flu season. Getting vaccinated against the flu every year is important, especially because the vaccine strains can change from year to year, as will happen for the 2013-2014 season.

Influenza Still Increasing in AZ

January 25th, 2013

Yesterday afternoon’s weekly flu report shows that influenza is still circulating widely in AZ…  with a steep increase in the last couple of weeks.  The strain that’s circulating is mostly Type A - H3N2 which can be more severe than the 2009 H1N1, especially for seniors. There are plenty of B strains going around too.  But you can still find a vaccine through Stop the Spread AZ – just be sure to call the place first to make sure they still have it and if you need an appointment.  By the way- this year’s vaccine is still a perfect match for the circulating strains.  The best prevention besides getting vaccinated is to wash your hands and make sure you cough or sneeze into your sleeve instead of your hand.  Most importantly…  don’t send your kids to school sick and don’t go to work sick either.

Flu Down Under- 2012

August 24th, 2012

The Southern Hemisphere has its flu season during our Summer- so every year around now we watch influenza activity “down under” to get an idea of what we might expect for our upcoming flu season.   Here’s the scoop right now.  Flu south of the equator has already peaked and continues to decline.  There’s been a lot of variation in the dominant viruses in each country this season.  Many South American countries have mostly had the H1N1 “pandemic strain” while others like Southern Africa, Australia and New Zealand all had a lot of influenza A (H3N2), with co-circulation of influenza B.  You can check out more on the World Health Organization’s main influenza website and the Australian Health Ministry’s surveillance website.  

The formula in this year’s US vaccine is a good match for what’s been circulating in the Southern Hemisphere so far this year (Influenza A H3N2 and H1N1, and influenza B).   Some of the manufacturers of the vaccine have already delivered some doses- and you’ll no doubt start seeing those “flu shots here” signs at a pharmacy near you shortly.

A Virus is Born

December 5th, 2011

The CDC confirmed the birth of a new influenza virus in this week’s MMWR Weekly Report.  The newborn is named “Swine-origin Triple Reassortant Influenza A (H3N2) (S-OtrH3N2)”.  The hybrid virus was found in a handful of school-age kids in Iowa recently- and luckily the kids recovered and none were hospitalized.  Nobody outside the initial cluster has been infected (a good thing) meaning it doesn’t look like the new virus is very good at moving person to person (yet).  The scientists think that the new virus is a new re-assortment of the RNA among the run-of-the-mill H3N2 and the 2009 H1H1 pandemic strains. The latest details are in this week’s CDC’s Weekly Report. All you virophiles can find a representation of the virus’s RNA on this special CDC website

Is this a new pandemic, you ask?  Probably not.

Influenza Widespread in AZ

January 6th, 2011

With last year’s pandemic, we saw how influenza can be unpredictable in terms of who it affects most, when it occurs, and what strains will circulate.  This season we are back to a more usual flu season, at least so far.  Our first laboratory-confirmed cases were detected earlier than most years (at the end of September), but influenza just kind of bumped along until it really started picking up speed in the in the last few weeks.  All counties have found laboratory-confirmed cases this season, and we’re declaring flu to be at “widespread” levels in this week’s Surveillance Report.

We’ve found all three of the common types of influenza virus in Arizona this season, our old friend Influenza A (H3N2), the 2009 H1N1 pandemic strain and influenza B.  In most seasons we see at least two different strains (like this year).  Last year was unique, and the H1N1 virus displaced all the other influenza viruses.  Our state lab has done a lot of PCR and culture testing to find out more details about the circulating viruses, and the good news is that, so far, the three strains in the vaccine are a good match with the circulating strains in Arizona and nationally.

This year, CDC started distributing vaccine to state and local programs earlier than ever.  Despite the fact that there has been plenty of vaccine in Arizona since early fall, demand by the public for flu vaccine has been very light this year. Because Arizona normally has a late season peak in flu, it is not too late to vaccinate. Our Immunizations team continues to work with counties and The Arizona Partnership for Immunization (TAPI) to encourage continuing flu vaccination through the spring.  You can find your nearest flu shot clinic by visiting our flu shot locator.

Seasonal Flu News

August 9th, 2010

The FDA approved this year’s (2010-2011) flu vaccine for the US.  This year’s shot will protect folks from 3 strains of influenza including the pandemic strain from last year.  The technical terms for the strains in this year’s shot are the “A/California/7/09 (H1N1)-like virus (i.e. pandemic virus”; the “A/Perth /16/2009 (H3N2)-like virus”; and the “B/Brisbane/60/2008-like virus”.  For the first time, the CDC is recommending that everybody over 6 months old get a seasonal flu shot.  The supply of vaccine should be robust- as there are now 13 brand names and manufacturers for this year’s vaccine, so if there is a problem with one of the suppliers (as was the case in 2004) it’s unlikely to create a major supply disruption. You can read more in the  FDA’s announcement this week.


Last week, the CDC’s Advisory Committee on Immunization Practices recommended that doctors avoid using the flu vaccine made by CSL Biotherapies (an Australian company) for kids under 8 years old because of unexplained  fevers in kids that got the vaccine over the last several months in Australia and New Zealand.


The pandemic flu strain (A/California/7/09 (H1N1)-like virus) pretty much completely displaced the H3N2 strain last flu season in North America.  However, the flu outbreaks that have occurred this summer (at summer camps, day care centers and sports camps and the like) have mostly been the A/Perth/16/2009-like H3N2 virus.  Both strains are included in this year’s seasonal flu shot.