1

INFLUENZA VIRUSPHA 5601: PEDIATRIC AMBULATORY CAREDR. ANGELA THORNTON, PHARMD

Jaslyn AdamsAlesha DaleyCorey GammonJayme Rentz

2

DEFINITION Influenza, commonly known as "the flu," is a

very contagious viral infection of the respiratory tract. Influenza affects all age groups, however children are at higher risk than adults.

3

ETIOLOGY Influenza virus:

Belongs to the family Orthomyxoviridae Large single-stranded RNA virus Has 2 major surface proteins that determine

serotype Hemagglutin (HA) Neuraminidase (NA)

Divided into three types: A, B, and C Types A and B are primarily responsible for the

epidemic disease Types A and B are further divided into specific

serotypic strains Type C is primarily responsible for sporadic cases

of upper respiratory tract disease

4

EPIDEMIOLOGY Location: Influenza affects all countries

around the world Transmission: may be transmitted through

large liquid droplets (ex: sneezing into the air) or touching contaminated surfaces and then touching eyes, nose, or mouth. A person with influenza may be contagious for up to ten days after the onset of symptoms.

5

Temporal Pattern: “Flu Season” in the U.S. is generally from October to May with a peak in February.

While everyone is at risk for getting the flu, there are some high risk populations: Children younger than 5 years old Adults older than 65 years old Pregnant Women Patients with a weakened immune system Patients with chronic illnesses including:

Asthma COPD Cystic fibrosis HIV/AIDs Cancer

6

7

8

9

PATHOPHYSIOLOGY Influenza virus is transmitted from infected

mammals through the air by coughs or sneezes, creating a aerosols like effect that contains the influenza virus.

10

SYMPTOMS Fever

Typically lasts 2-4 days (100°F or higher under the arm, 101°F orally, or 102°F rectally)

Myalgias Chills Headache Malaise Anorexia Coryza Pharyngitis Dry cough

May persist for a long period of time

11

DIAGNOSIS1. If flu-like symptoms arise in the midst of flu

season or a flu pandemic, the diagnosis is generally geared towards influenza

a. Flu Season: October through May; peak in February

2. Laboratory methods to diagnose influenza:a. Viral Culture:

i. If implemented within the first four days of the illness, the virus may be isolated from the nasopharynx via nasopharyngeal swab, nasal swab, or nasal aspirate.

b. Rapid Influenza Diagnostic Tests:i. These test may not detect all strains of influenza,

and may not differentiate between Influenza A and Influenza B

12

ii. Polymerase chain reaction (PCR)1. Detects viral RNA in the presence of a virus

iii. Immunosorbent assay1. Detects the presence of antigens and antibodies

c. Serologic testing: i. Tests for antibodies in the serumii. Needs to be drawn during illness and post illness to

confirm influenza iii. Will not aid in clinical decision making, will only

confirm diagnosisd. These test should only be implemented if the

results will influence the clinical care of the patient or of other patients

13

DIFFERENTIAL DIAGNOSIS

Symptoms Influenza Common Cold

Pharyngitis Infectious mononucleosis

Meningitis

Fever Common Uncommon

Possible Common Common

Aches/Chills Common Uncommon

Possible Common Common

Fatigue/Weakness

Common Possible Uncommon Common Possible

Cough/Sneezing Common Common Common Uncommon Uncommon

Headache Common Uncommon

Possible Uncommon Common

Stuffy Nose Possible Common Uncommon Uncommon UncommonSore Throat Possible Common Common Common Uncommon

14

COMPLICATIONS Otitis media Pneumonia

Secondary to bacterial infection Acute myositis

Usually seen with Type B Myocarditis Toxic shock syndrome

15

TREATMENT & PREVENTION

16

METHODS Supportive care Pharmacological Nonpharmacological Alternative medicine and therapies

17

SUPPORTIVE CARE Acetaminophen (Tylenol)

10-15mg/kg/dose orally every 4-6 hours Ibuprofen (Motrin)

5-10mg/kg/dose orally every 6-8 hours Not for children < 6 months

18

OSELTAMIVIR (TAMIFLU) Mechanism of action

Inhibits Influenza virus neuraminidase, affecting particle release Indicated for Influenza Type A&B

Used to treat patients at least 2 weeks old and prophylaxis in children 1 year and older

Dosage 2weeks- 1year: 3mg/kg twice daily for 5 days or 0.5mL/kgf oral

suspension 1-12 years: 10 capsules 30-75mg twice daily

Weight dependent Adverse Effects

Nausea, vomiting, arrhythmia, swelling of face or tongue, abdominal pain

Monitoring Parameters Renal function, serum glucose, in diabetic patients signs of

unusual behavior

19

NON-PHARMACALOGICAL Get plenty of rest Increase fluid intake

Warm tea Soup

Frequently wash hands Give warm bath or warm compress Avoid contact with sick people

20

INFLUENZA VACCINE Types seen in the U.S.

A/California/7/2009 (H1N1) pdm09-like virus A/Victoria/361/2011 (H3N2)-like virus B/Wisconsin/1/2010-like virus

Determined based on age 1 dose is preferred, unless vaccine has never

been received Side effects:

Injection site reaction Low/ high grade fever Body aches

21

MF59 Used since 1997 as TIV adjunct to seasonal

vaccination Used in children 6-72 months and adults Must have not previously received influenza

vaccine Combined with trivalent inactivate influenza

vaccine (TIV), abbreviated ATIV

22

ALTERNATIVE PREVENTION Mainly for prevention American ginseng (panax quinquefolius)

Don’t take with Tylenol Increase Vitamin D intake Cinnamon Hydrogen peroxide in ear Garlic

23

REFERENCES Nicola J. High, “Molecular Medical

Microbiology”2002, Pages 1967–1988 Volume 3, School of Biological Science, University of Manchester, Manchester, UK. <http://www.sciencedirect.com/science/article/pii/B9780126775303503123>

Kliegman, Wright P. Influenza Viruses. In: Saunders, An Imprint of Elsevier. Nelson Textbook of Pediatrics. New York: McGraw-Hill; 2007. chapter 255.

CDC. Prevention and control of influenza with vaccines: recommendations of the Advisory Committee on Immunization Practices (ACIP), 2010. MMWR 2010;59 (No. RR-8).

24

Vesikari, Timo et al. Oil-in-Water Emulsion adjuvant with Influenza Vaccine in Young Children. N Engl J Med 2011; 365:1406-1416

Harper SA, Bradley JS, Englund JA, et al. Seasonal influenza in adults and children—diagnosis, treatment, chemoprophylaxis, and institu- tional outbreak management: clinical practice guidelines of the Infectious Diseases Society of America. Clin Infect Dis 2009;48:1003–32.

CDC. Influenza-Associated Pediatric Mortality, 2013. < http://gis.cdc.gov/GRASP/Fluview /PedFluDeath.html>