1. Influenza Presentation for Health Care Workers
We are glad you can join us for a presentation on influenza geared toward health care workers working in facility settings. This presentation has been updated for the season.

2. LEARNING OBJECTIVES To gain a better understanding of:
Influenza Virus and the Disease:
Transmission, symptoms, diagnosis, and treatment
Influenza Vaccine
Components, types available, effectiveness, benefits and side effects
The objectives of this presentation are to gain a better understanding of influenza the disease, influenza the vaccine and influenza control measures.

3. INFLUENZA VIRUS & DISEASE

4. DISEASE FACTS Influenza, commonly known as ‘the flu’
A respiratory illness caused by influenza A or B viruses that can be mild or serious
Symptoms usually last 7-10 days, sometimes longer in the elderly
Cough and fatigue can last weeks
Influenza is very contagious, you can spread the disease 24 hours before you become symptomatic and for about 5 days after symptom onset
Influenza is a respiratory infection caused primarily by influenza A and B viruses. In Canada, influenza generally occurs each year in the late fall and winter months. Symptoms typically include the sudden onset of high fever, cough and muscle aches. Other common symptoms include headache, chills, loss of appetite, fatigue and sore throat. Nausea, vomiting and diarrhea may also occur, especially in children. Most people will recover within a week or ten days, but some are at greater risk of more severe complications, such as pneumonia. People with chronic diseases may have worsening of their underlying disease.
Common symptoms: high fever, cough, muscle aches
Children: may transmit the virus for longer than 7 days [CDC (2013). How flu spreads. Retrieved from
Seasonal: Occurs annually in Canada in late fall and winter months
Global Attack Rate: 5-10% in adults and 20-30% in children
Incubation Period: Average 2 days (ranges from 1-4 days) for seasonal influenza
Period of Communicability: In adults, viral shedding is greatest in the first 3-5 days of illness. In young children, virus shedding can occur for longer, 7-10 days, and may be even longer in severely compromised persons.
Heymann, D. (ed.) (2008). Control of Communicable Diseases Manual, 19th edition. Washington, American Public Health Association, pp

5. MODES OF TRANSMISSION Respiratory Droplet Transmission
Droplets are generated when a sick person coughs or sneezes
droplets can travel up to two meters in distance
Droplets need to be inhaled by nearby individuals or land on their mouth, eyes or nose to transmit the virus
Contact Transmission
Respiratory droplets can also contaminate surfaces or objects
the flu virus can survive up to 48 hours on hard, non-porous surfaces such as stainless steel
If an individual touches a surface or object contaminated with the flu virus and then touches their mouth, nose or eyes the virus can be transmitted
(CDC, 2013; Public Health Agency of Canada, 2011; WHO, 2010)
Influenza is primarily transmitted by droplet spread through coughing or sneezing and may also be transmitted through direct or indirect contact with contaminated respiratory secretions. The incubation period of seasonal influenza is usually two days but can range from one to four days. Adults may be able to spread influenza to others from one day before symptom onset to approximately five days after symptoms start. Children and people with weakened immune systems may be infectious longer.

6. WHO IS MOST VULNERABLE TO THE FLU?
Adults and children with underlying health conditions
Residents of LTCHs and other chronic care facilities
People > 65 years of age
Children < 60 months of age
Pregnant women
Indigenous peoples
The people at greatest risk of influenza-related complications are adults and children with underlying health conditions, residents of nursing homes and other chronic care, facilities, people 65 years of age and older, children under 60 months of age, pregnant women, and Indigenous peoples.

7. FLU – DISEASE DISTRIBUTION
Globally
1 billion cases of influenza around the world annually, resulting in 250,000 to 500,000 deaths
In Canada
23,000 laboratory-confirmed cases of influenza annually
Influenza is estimated to be responsible for:
12,200 hospitalizations
3,500 deaths
Influenza and pneumonia is ranked among the top 10 leading causes of death
Global
Influenza occurs globally with an annual attack rate estimated at 5–10% in adults and 20–30% in children
Worldwide, annual epidemics result in an approximately one billion cases of influenza, about three to five million cases of severe illness, and about 250,000 to 500,000 deaths.
National
Influenza and pneumonia is ranked among the top 10 leading causes of death in Canada(2). Current influenza activity information can be found on the FluWatch website. The FluWatch program collects data and information from various sources to provide a national picture of influenza activity. An average of 23,000 laboratory-confirmed cases of influenza is reported to the FluWatch program each year. Although the burden of influenza can vary from year to year, it is estimated that, in a given year, an average of 12,200 hospitalizations related to influenza(3) and approximately 3,500 deaths attributable to influenza occur
It should be noted that the incidence of influenza is often underreported since the illness may be confused with other viral illnesses and many people with influenza-like illness (ILI) do not seek medical care or have viral diagnostic testing done.

8. INFLUENZA SYMPTOMS Symptoms Flu Cold Fever Usually high, sudden onset,
lasts 3-4 days
*May not be prominent in
adults > 65 years
Rare
Chills
Common
Sore throat
Coughing
Common – can be severe
Sometimes - mild to moderate
Muscle aches and pains
Common – often severe
Sometimes, - mild
Headache
Tiredness and weakness
Common – severe,
(may last 2-3 weeks)
Sometimes - mild
Runny, stuffy nose
Sneezing
Sometimes
Gastrointestinal Symptoms
Unusual
Symptoms typically include the sudden onset of high fever, cough and muscle aches. Other common symptoms include headache, chills, loss of appetite, fatigue and sore throat. Nausea, vomiting and diarrhea may also occur, especially in children. Most people will recover within a week or ten days, but some, including those 65 years of age and older, young children, and adults and children with chronic conditions, are at greater risk of more severe complications or worsening of their underlying condition.

9. SICK WITH THE FLU? Stay home and get plenty of rest
Seek medical attention as appropriate
Limit your contact with others
Wash your hands frequently with soap and water or with alcohol-based hand sanitizer, particularly after coughing or sneezing
Ensure you practice respiratory etiquette (cough/sneeze into your sleeve or into a tissue, then wash your hands or use hand sanitizer)
Reference:
Ministry of Health and Long-Term Care (2015). Flu facts. Retrieved from

10. CONFIRMING DIAGNOSIS Nasopharyngeal (NP) Swab
Should be obtained from the most severe and most recently ill residents (i.e. during the first 4 days of their illness)
Rapid test is takes a few hours; PCR up to 3-4 days and culture up to 10 days.
Serology may be done but not very common. This test would need to be done as an acute and convalescent serology taken days apart.
Reference:
Infectious Disease Protocols (2014). Appendix A: Disease Specific Chapters

11. TREATMENT
Antiviral treatment for influenza must be started within 48 hours (or less) of onset of symptoms for maximum effectiveness
Oseltamivir (Tamiflu)
effective against influenza A and B
recommended drug of choice for both prophylaxis and treatment in an influenza outbreak
Zanimivir (Relenza)
used when predominant circulating strain is
resistant to Tamiflu
Rapid test is takes a few hours; PCR up to 3-4 days and culture up to 10 days.
Serology may be done but not very common. This test would need to be done as an acute and convalescent serology taken days apart.
Reference:
Infectious Disease Protocols (2014). Appendix A: Disease Specific Chapters

12. INFLUENZA PREVENTION

13. INFLUENZA VACCINE
Vaccination is the most effective way to prevent influenza and its complications.
Reference:
NACI Statement

14. INFLUENZA VACCINE – HOW DOES IT WORK?
Flu vaccines cause antibodies to develop in the body about two weeks after vaccination
These antibodies provide protection against infection with the viruses that are in the vaccine

15. INFLUENZA VACCINE RECOMMENDATIONS
Recommended for all individuals aged 6 months and older without contraindications
Evidence has shown that healthy people aged 5-64 years benefit from influenza immunization
Annual vaccination is required because:
the body’s immune response from vaccination diminishes within a year and
circulating influenza viruses change often, and specific strains are changed each year in the vaccine to match what is circulating
Vaccination is the most effective way to prevent influenza and its complications.
Annual vaccination is required because the body’s immune response from vaccination diminishes within a year. Also, because influenza viruses change often, the specific strains in the vaccine are reviewed each year by WHO and updated as necessary so that there is the greatest probability of matching circulating viruses.
in the elderly, antibody levels may fall below protective levels in four to six months (MOHLTC pg.19 .

16. INFLUENZA VACCINE COMPOSITION
Last Season
Trivalent vaccines will include:
A/Hong Kong/4801/2014 (H3N2)
A/Michigan/45/2015 (H1N1)pdm09
B/Brisbane/60/2008
Quadrivalent will also include:
B/Phuket/3073/ (Yamagata lineage)
This Season
Trivalent vaccines will include:
A/Singapore/INFIMH /2016 (H3N2)
A/Michigan/45/2015 (H1N1)pdm09
B/Colorado/06/2017
Quadrivalent will also include:
B/Phuket/3073/ (Yamagata lineage)
Changes from season components: replaced A/Hong Kong to A/Singapore. B components also change from B/Brisbane to B/Colorado
The antigenic characteristics of circulating influenza virus strains provide the basis for selecting the strains included in each year's vaccine.
Vaccine selection by the WHO generally occurs more than six months prior to the start of the influenza season to allow time for the vaccine manufacturers to produce the required quantity of vaccine.

17. NAMING THE VIRUS A / Michigan / 45 / 2015 (H1N1) Type Place Where
First Isolated
Strain
Number
Year of
isolation
Subtype
of H and N
Hemaglutinins (H) Neuraminadase (N)
Viral isolates are described according to type, geographical origin, strain number, year of isolation and subtype, in this order (e.g. A/Sydney/5/97 [H3N2]).
Although infrequent exceptions occur, humans are generally infected by viruses of the H1, H2 or H3 and N1 or N2 subtypes.

18. Live Attenuated Vaccines
INFLUENZA VACCINE - TYPES
Inactivated Vaccines
the virus has been disrupted by a detergent, or
viral components have been removed
Live Attenuated Vaccines
the virus has been attenuated weaken) so that they do not cause influenza
FluMist Quadrivalent
Influenza virus in the vaccine has been killed or weaken so that they do not cause influenza

19. INFLUENZA VACCINES - EXAMPLES
trivalent inactivated vaccine
For individuals age 65 years and older
Fluzone High-dose
Quadrivalent inactivated vaccines
For individuals age 18-64
FluLaval Tetra
Fluzone Quadrivalent
Nasal spray form
For individuals age 2-59 (publicly funded for age 2-17)
Not recommended for pregnant women or people with compromised immune system
FluMist
NACI recommends that high-dose TIV should be offered over standard-dose TIV to persons 65 years of age and older. NACI concludes that, given the burden of disease associated with influenza A(H3N2) and the good evidence of better efficacy compared to standard-dose TIV in this age group, high-dose TIV should be offered over standard-dose TIV to persons 65 years of age and older

20. MORE ABOUT FLUMIST Alternative to the injection!
Publicly funded for ages 2-17
Can be administered by a pharmacist (ages 5-17 only) or health care provider
For individuals years, it is available for purchase, by prescription, and needs to be administered by your healthcare provider
Not recommended for pregnant women or persons with immune compromising conditions
Most common adverse reaction is nasal congestion and runny nose

21. SUMMARY ON INFLUENZA VACCINE
It is a safe and well-tolerated vaccine
It cannot cause influenza illness because:
the inactivated influenza vaccines do not contain live virus
the viruses in live attenuated influenza vaccines are weakened so that they cannot cause influenza
Reference:
NACI statement

22. INFLUENZA VACCINE IS PARTICULARLY RECOMMENDED FOR
Pregnant women
Those with chronic health conditions (including morbid obesity)
Those living in LTCHs and other chronic care facilities
All children 6 months of age to less than 5 years of age and those ≥ 65 years
Indigenous Peoples
Children and adults with neurologic and neurodevelopmental conditions
Health care providers
References:
NACI statement

23. NACI STATEMENT ON HEALTHCARE PROVIDERS AND FLU VACCINE 2018-19
“Transmission of influenza between infected HCWs and their vulnerable patients results in significant morbidity and mortality…HCWs should consider annual influenza immunization included in their responsibility to provide the highest standard of care…
In the absence of contraindications, refusal of HCWs to be immunized against influenza implies failure in their duty of care to patients.” pg.25, NACI
We want to reinforce that the transmission of influenza between infected HCWs and their vulnerable patients/residents can result in significant morbidity and mortality.
Reference:
NACI Statement , pg.26

24. EFFECTIVENESS OF INFLUENZA VACCINE
Protective antibody levels are generally achieved 2 weeks following immunization
Immunization has been shown to reduce the number of physician visits, hospitalizations and deaths in high-risk persons 18 to 64 years of age
Efficacy may be lower in certain populations (e.g., persons with immune compromising conditions, elderly persons)
Immunization has been shown to reduce the number of physician visits, hospitalizations and deaths in high-risk adults
The vaccine effectiveness of seasonal influenza vaccines is a measure of how well the seasonal influenza vaccine prevents influenza virus infection in the general population during a given influenza season. If the vaccine effectiveness is high, it indicates that individuals who have received the seasonal influenza vaccine are less likely to have an influenza illness. If the vaccine effectiveness is low, it indicates that the seasonal influenza vaccine may not be as likely to prevent influenza illness in the vaccinated population. It is important to remember that even with low vaccine effectiveness, substantial numbers of influenza-related illnesses can still be prevented.
Each season, studies are conducted in some countries to measure the effectiveness of influenza vaccine. During seasons when most circulating influenza viruses are similar to the viruses in the influenza vaccine, the vaccine can reduce the risk of illness caused by influenza virus infection by about 50-60% among the overall population.
References:
NACI Statement , pgs. 12
WHO, Q&A, Feb 26,

25. INFLUENZA VACCINE EFFECTIVENESS FOR 2017-18 SEASON
Most prominent circulating viruses for the influenza season in Canada were:
A(H3N2)
B(Yamagata) – early circulation in the season
Low vaccine effectiveness (VE) was anticipated for these strains due to the low effectiveness documented in the southern hemisphere - 10% for A(H3N2)
VE against influenza A(H3N2): 17% overall; 10% in adults years of age
VE against influenza B: 55% overall; 40% in adults years of age
VE against any influenza A and B combined was 42% overall; 31% in adults years of age
PHO did a webinar in April 2018 on VE for the season (presenter was author of the article sourced above) which I missed and am waiting for the slides to be posted to the PHO website. If there are any major changes to these stats, I will communicate this.
Source: Danuta M. Skowronski, et al. Early season co-circulation of influenza A(H3N2) and B(Yamagata): interim estimates of 2017/18 vaccine effectiveness, Canada, January Euro Surveill. 2018;23(5):

26. CONTRAINDICATIONS AND PRECAUTIONS TO VACCINE
Flu vaccine is NOT recommended for anyone:
who has experienced an anaphylactic reaction following a previous dose of vaccine or to any of the vaccine components (except eggs)
who have developed Guillain-Barré Syndrome (GBS) within six weeks of influenza vaccination,
Egg allergic individuals without other contraindications can be administered with the full dose of the vaccine
Anyone experiencing a serious acute illness should postpone until symptoms resolve
If significant nasal congestion is present, defer Flumist until illness resolved or give injection
NACI statement pg. 9
Egg-allergic individuals may be vaccinated against influenza (any product) without prior influenza vaccine skin test and with the full dose, irrespective of a past severe reaction to egg (NACI Statement , pg. 9)
As with all vaccine administration, immunizers should have necessary equipment to be prepared to respond to a vaccine emergency
Reference:
NACI Statement , pgs. 7, 20-23
*Seek medical advice prior to vaccination

27. COMMON REACTIONS TO THE FLU SHOT
Common mild reactions in adults:
Soreness, redness or swelling at the injection site (usually lasts less than 2 days)
low grade fever and aches (can last 1-2 days)
Serious side effects are very rare
The mild reactions people have to the flu shot are considerably less severe than actually having the flu
Adjuvanted TIV tends to produce more extensive injection site reactions than unadjuvanted – but still mild and resolve within a few days.
High-dose tends to induct higher rates of systemic reactions post injection compared with standard does TIV, but are short lived.
NACI Statement , page 19

28. IF PEOPLE GET SICK AFTER HAVING THE FLU SHOT IT IS BECAUSE…
They have contracted a respiratory virus that causes similar symptoms
They were already exposed to the flu virus prior to vaccination
They were among the 40-50% of the population where the shot was not effective
They have contracted a different strain of flu that is circulating and not contained in the vaccine what is referred to as a ‘vaccine mismatch’
The symptoms of influenza are similar to many other respiratory infections
Takes 2 weeks for the vaccine to be effective so if a person has already been exposed to the virus prior to vaccination they could still get the illness.
The flu vaccine is not perfect - during seasons when circulating influenza viruses are similar to the viruses in the influenza vaccine, the vaccine can reduce the risk of illness caused by influenza virus infection by about 50-60% among the overall population. It is important to remember that even with low vaccine effectiveness, substantial numbers of influenza-related illnesses can still be prevented.
A mismatch of the vaccine and circulating strain occasionally occurs - Vaccines against seasonal influenza must be frequently updated and the process for selecting the viruses and manufacturing the influenza vaccines starts several months before the influenza season begins. Detailed, timely data on viruses that are circulating and infecting humans globally are gathered, shared among countries and scientists, and are eventually used to formulate the upcoming seasonal influenza vaccines. Influenza viruses are constantly changing, including during the time between vaccine virus selection and the influenza season. If these changes lead to antigenic differences between the circulating seasonal influenza viruses and those viruses that are included in the seasonal influenza vaccine, then the vaccine and circulating viruses may not be closely related. The degree of similarity or difference between the circulating viruses and the viruses in the vaccines is often referred to as “vaccine match” or “vaccine mismatch”.
WHO, Q&A, Feb 26,

29. VIDEO – The Flu: don’t pass it on

30. ADDITIONAL INFORMATION
Ontario Respiratory Virus Bulletin: io-Respiratory-Virus-Bulletin.aspx
Canadian Flu Watch:
maladie/flu-grippe/surveillance/index-eng.php
National Advisory Committee on Immunization (NACI):
immunization-guide-statement-seasonal-influenza-vaccine html
Just Clean Your Hands: nds/Pages/Just-Clean-Your-Hands.aspx
Video: The Flu – don’t pass it on!

31. THANK YOU