What’s New with Flu? · •Clinical presentation •Symptoms develop after an incubation period...
Transcript of What’s New with Flu? · •Clinical presentation •Symptoms develop after an incubation period...
What’s New with Flu?
Han Ha Youn, M.S.
Influenza Surveillance and Response Coordinator
Disease Investigation Branch
Hawaii Department of Health
History
History
• 1918 Spanish Flu Pandemic• Approximately 500 million people (one third of the word’s
population) became infected• At least 50 million deaths worldwide• About 675,000 in the United States
• High mortality in healthy people
History
• 2009 H1N1 (Swine Flu) Pandemic• First detected in the United States and
quickly spread across the country and the world.
• 60.8 million cases• 274,000 hospitalizations• 12,500 deaths in the United States• Estimated between 151,700 and 575,400
deaths worldwide
Background
• Arguably most common respiratory viral infection worldwide• Causes serious disease annually in US with 5-20% infected• Usual targets: extremes of ages, those with underlying
medical conditions• Transmission
• Usually spread person-to-person via large respiratory droplets
• May pick up from contaminated surfaces and then touch mucosal areas
Symptoms• Clinical presentation
• Symptoms develop after an incubation period of approximately 2 days (ranges from 1-4 days)
• Contagious approximately 1 day before and up to 7 days after symptom onset
• Illness duration 3 to 7 days
Day 0 1 2 3 4 5 6 7 8 9 10 >>>
Flu symptoms lasting 3-7 days
Contagious PeriodFrom 1 day before to 7 days after symptoms
Incubation Period 2 days
Symptoms• Abrupt onset of nonspecific constitutional and respiratory signs and symptoms
• Fever• Nonproductive cough• Sore throat• Fatigue• Body aches• Headache• Runny nose• May exacerbate underlying medical conditions• Complications
• Dehydration• Pneumonia• Ear/sinus infections
Prevention and ControlPreventing and controlling a flu infection
requires many steps including:
1. Vaccination
2. Hand hygiene
3. Antiviral treatment and prophylaxis
4. Avoid touching your eyes, nose, and mouth
5. Routine cleaning of surfaces
Flu Season
When is flu season?
First week of October to last week of September (MMWR week • 40 to 39)Seasonal flu outbreaks can happen as early as October and as late as May.•
CDC. Key Facts About Seasonal Flu Vaccine
Influenza Vaccine
2018-2019 Influenza vaccine composition
A/Michigan/45/2015 (H1N1)pdm09-like virusA/Singapore/INFIMH-16-0019-2016 (H3N2)-like virusB/Colorado/06/2017-like virus (Victoria Lineage)B/Phuket/3073/2013-like virus (Yamagata Lineage)
CDC. Prevention and Control of Seasonal Influenza with Vaccines: Recommendations of the Advisory Committee on Immunization Practices – United States, 2018-19 Influenza Season. MMWR Morb Mortal Wkly Rep. 2018 Aug 24; 67(3).
Influenza Vaccines – 2018-2019 Season
CDC. Prevention and Control of Seasonal Influenza with Vaccines: Recommendations of the Advisory Committee on Immunization Practices – United States, 2018-19 Influenza Season. MMWR Morb Mortal Wkly Rep. 2018 Aug 24; 67(3).
Influenza Vaccine
Why get vaccinated against influenza (flu)?
The best way to protect against flu is to get a flu vaccine every flu season.•
Flu viruses are constantly changing, so flu vaccines may be updated from one season to the •
next to protect against the viruses that research suggests will be most common during the upcoming flu season.A person• ’s immune protection from the flu vaccine declines over time. Yearly vaccination is needed for the best protection
What are the benefits of getting the flu vaccine?
The flu vaccine can provide:Protection for yourself (reduce your risk of getting sick or being hospitalized)•
Protection for others at high risk of developing serious complications from flu•
Protection for children too young to be vaccinated•
Protection for pregnant women and their newborns•
Protection for patients•
CDC. Key Facts About Seasonal Flu Vaccine
Influenza Vaccine
When to get vaccinated?
• Fall is the time to get your annual flu vaccine. If possible, get our flu vaccine by the end of October!• However, as long as flu viruses are circulating, it is not too late to get vaccinated.• The timing of flu outbreaks is unpredictable. Seasonal flu outbreaks can happen as early as October
and as late as May. It is best to get vaccinated before influenza viruses start to spread in the community since it takes about two weeks after vaccination for antibodies to develop in the body and provide protection against the flu.
CDC. Key Facts About Seasonal Flu Vaccine
Influenza Vaccine
How well do flu vaccines work?
• Flu vaccine reduces the risk of doctor visits due to flu by ~50-60%• A flu vaccination does not guarantee protection against the flu and some vaccinated people may still
get sick. However, people who get a flu vaccine are less likely to get sick with flu or hospitalized than someone who does not
• Efficacy of the vaccine changes every year depending on the match between the circulating strains and the ones included in the vaccine
CDC. Key Facts About Seasonal Flu Vaccine
Flu Vaccination in Healthcare Personnel
Flu Vaccination in Hawaii’s Healthcare Personnel
CDC. FluVaxView
Flu Vaccination in Hawaii’s Healthcare Personnel
Flu Vaccination in Hawaii’s Healthcare Personnel
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Percent of workers vaccinated National Goal — 90% (Healthy People 2020) National Average — 88% (2016/2017) Hawaii Average — 82% (2016/2017)
Flu Vaccination in Hawaii’s Healthcare Personnel
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Vaccination Rates by HCW Category
Volunteers
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Flu Vaccination in HawaiiInfluenza Vaccination Coverage ≥18 Years
CDC. FluVaxView
38.5%
Flu Vaccination in HawaiiInfluenza Vaccination Coverage 6 Months – 17 Years
CDC. FluVaxView
61.0%
Stop Flu at School (SFAS)
Free• flu vaccinesKindergarten through • 8th grade at participating eligible schoolsOctober • 15 – December 7, 2018177 • public schools statewide
For more information on the SFAS program:http://health.hawaii.gov/docd/about-us/programs/stop-flu-at-school/
A review of last season…
High severity season•
High levels of outpatient clinic and emergency department visits for ILI•
High influenza• -related hospitalization ratesElevated and geographically widespread activity across the country for an extended •
period of timeActivity began increasing in November and reached an extended period of high activity during •
January and FebruaryInfluenza A(H• 3N2) viruses predominated overall
Influenza B viruses were reported more frequently than influenza A viruses from early •
March until mid-JuneThe majority of circulating viruses were similar to the cell• -grown reference viruses representing the 2017-2018 influenza vaccine viruses
Season Severity Assessment
Laboratory-Confirmed Influenza Associated Hospitalizations
CDC. Weekly U.S. Influenza Surveillance Report
Influenza Season TrendsPercentage of Influenza-like Illness (ILI) Visits Reported to CDC for
Selected Previous Seasons From All US States 2017-2018 Flu Season
Key messages:1. Timing and length of
influenza illness varies from season to season
2. Influenza varies in severity from season to season
CDC. Weekly U.S. Influenza Surveillance Report
Surveillance in Hawaii
Percentage of Influenza-like Illness (ILI) Visits Among All Outpatient VisitsReported by Hawaii Sentinel Providers
Hawaii Department of Health Weekly Influenza Surveillance Report
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NATIONAL BASELINE
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2017 ̶ 18 Influenza Season (N=51,222)
Surveillance in Hawaii
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Hawaii Department of Health Weekly Influenza Surveillance Report
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2017 ̶ 2018 Influenza Season