Sw Ine Flu Final

INFLUENZA A (H1N1)

LIZA D. MARIPOSQUE, M.D.2nd Year Family Med Resident

Perpetual Succour HospitalSeptember 2009

OBJECTIVES:

To present a case of H1N1 in a 28 years old pregnant patient.

To discuss Influenza A H1N1 Epidemiology Signs & symptoms Risk factors Diagnosis Treatment and Prevention

J. L., 28 years old, pregnantG4P1-1-1-2, 13 wks 6/7 days AOG by LMPMarriedFilipinoRoman CatholicSambag I, Cebu City admitted for the 4th times at PSH

CC: fever, cough & shortness of breath

PAST MEDICAL HISTORY

Non-diabetic, non-hypertensive,

non-asthmatic.

Non-smoker, non-alcohol beverage drinker Allergy: shrimp

HFD: HPN, DM 2, Bronchial Asthma

PAST MEDICAL HISTORY

2004 – PSH : NSVD (PT) 2005 – PSH : Ectopic pregnancy,

S/P Salpingectomy R 2008 – PSH : NSVD (FT)

2 wks PTA : Herpes Zoster infection

OBSTETRICAL HISTORY

Menarche - 10 y.o x 28 days cycle 7 days duration

LMP: April 1, 2009 AOG: 13 wks & 6 days EDC: January 8, 2010

HISTORY OF PRESENT ILLNESS

3 days PTA, sudden onset of fever with cough, coryza, headache & poor appetite.

Night PTA, had shortness of breath and spontaneously resolved, but recurred in the morning PTA thus prompted admission.

PHYSICAL EXAMINATIONS

Examined conscious, coherent & slightly respiratory distress.

BP: 110/80 mmHg HR: 86 bpm

RR: 29 cpm T: 36.8 0C

Wt: 59.8 kg

PHYSICAL EXAMINATION

SKIN: Fair, warm, no rashes, no cyanosis

HEENT: Anecteric sclerae, pinkish palpebral conjunctivae, nasal congestion, non-hyperemic tonsils.

NECK: No lymphadenopathy

C/L: Equal chest expansion, clear breath sounds, no rales, no wheeze.

PHYSICAL EXAMINATION

ABDOMEN: Flabby, normoactive bowel sound, soft, nontender,

no hepatomegaly, no palpable mass.

GUT: fundus 4 fingerbreaths below umbilicus, FHT: 139 bpm, (-) KPS

EXT. : No edema, strong pulses, CRT <2 sec.CNS: WNL

ADMITTING IMPRESSION

Upper Respiratory Tract Infection

PU 13 wks 6/7 AOG, Not in labor

COURSE IN THE WARD

1ST HOSPITAL DAY

P: Cough, fever, coryza, shortness of breathS: w/ cough, w/ coryza O: conscious, coherent & not in respiratory

distress.BP: 100/70-110/80 mmHg PR: 76-85 bpm RR: 19-29 cpm T: 36.9-37.5 0C

COURSE IN THE WARD

1ST HOSPITAL DAY

SKIN: Fair, warm, no rashes.HEENT: Anecteric sclerae, pinkish palpebral conjunctivae,

with both nasal congestionnasal congestion, non-hyperemic tonsils.NECK: No lymphadenopathyC/L: Equal chest expansion, clear breath sound, no rales,

no wheeze.ABDOMEN: Flabby, normoactive bowel sounds, soft,

nontender, no hepatomegaly, no mass.GUT: fundus 4 fingerbreaths below umbilicus

FHT: 139-160 bpm, (-) KPSEXT. : No edema, strong pulses, CRT <2 sec.CNS: WNL

COURSE IN THE WARD

1ST HOSPITAL DAY

A: Influenza A

R/O Influenza H1N1

Pregnancy Uterine 13 wks 6/7 AOG, not in labor

COURSE IN THE WARD1ST HOSPITAL DAY

P: > Oxygen inhalation.

> IVF started.

> Hypoallergenic diet.

> Labs: CBC, U/A, CXR w/ abdominal shield,

Screening test for Influenza A & B

LABORATORY RESULTS

CBC N.V. RESULTS

WBC 4-11.30 6.42

Neutrophils 47-80% 72

Lymphocytes 13-40% 16

Monocytes 2-11% 10

Eosinophil 0-5% 1

Basophil 2-4% 1

Hb 12-16 13.2

Hct 36-46% 38.7

plt 140-440 235

URINALYSIS RESULTS

Color & transparency Yellow, clear

Glucose NEG

Protein +

pH 6

Urine Ketone +

RBC/hpf 5-10 / hpf

WBC/hpf 0-2 / hpf

Epithelial cells rare

Mucus Threads abundant

Amorphous material rare

Bacteria rare

(Rapid Qualitative Test)

Sample Type: Nasopharyngeal Swab

Results: (+) Influenza A

(-) Influenza B

SCREENING TEST FOR INFLUENZA A & B

COURSE IN THE WARD1ST HOSPITAL DAY

P: >FHT monitoring BID.> Paracetamol 500 mg 4H prn for T≥38 0C & headache.> Sinupret 1 tab TID then revise to BID.> Salbutamol 1 neb q 6H.> Vit. C (Benutrex) 1 amp infused to present IVF ANST and in succeeding IVF to follow.> Prenatal Vit. (Beniforte) 1 cap OD is continued.> co-managed with OB.

COURSE IN THE WARD

2nd Hospital Day

S: no complaints

O: BP: 100/70-120/80 mmHg

PR: 77-91 bpm

RR: 18-20 cpm

T: 36.7-37 0C

COURSE IN THE WARD2nd Hospital Day

SKIN: Fair, warm, no rashes.HEENT: Anecteric sclerae, pinkish palpebral conjunctivae,

no nasal congestionno nasal congestion, non-hyperemic tonsils.NECK: No lymphadenopathyC/L: Equal chest expansion, clear breath sounds, no rales,

no wheeze.ABDOMEN: Flabby, normoactive bowel sound, soft,

nontender, no hepatomegaly, no mass.

GUT: fundus 4 fingerbreaths below umbilicus, FHT: 150-159 bpm , (-) KPSEXT. : No edema, strong pulses, CRT <2 sec.CNS: WNL

COURSE IN THE WARD

2nd Hospital Day

P: > Confirmatory throat swab test for Influenza A H1N1 c/o DOH.

> IVF terminated.

> meds given.

COURSE IN THE WARD3rd Hospital Day

S: No complaints

O: BP: 100/70-120/70 mmHg PR: 74-75 bpm RR: 18-19 cpm T: 36.4-36.7 0C

COURSE IN THE WARD3rd Hospital Day

SKIN: Fair, warm, no rashes.HEENT: Anecteric sclerae, pinkish palpebral conjunctivae,

no nasal congestionno nasal congestion, non-hyperemic tonsils.

NECK: No lymphadenopathyC/L: Equal chest expansion, clear breath soundsclear breath sounds, no rales,

no wheeze.ABDOMEN: Flabby, normoactive bowel sound, soft,

nontender, no hepatomegaly, no mass.GUT: fundus 4 fingerbreaths below umbilicus

FHT: 149-150 bpm, (-) KPSEXT. : No edema, strong pulses, CRT <2 sec.CNS: WNL

COURSE IN THE WARD3rd Hospital Day

A: > condition improved

> Patient discharge.

> Take home meds:

1. Bisolvon syr. 1 tbsp TID x 1 wk

2. Multivit. (Centrum) 1 cap OD

3. Beniforte 1 cap OD.

> Encourage oral fluid intake.

> ff-up with AP 1 wk after discharge.

COURSE IN THE WARD3rd Hospital Day

Final Diagnoses:

Influenza A H1N1 Pregnancy Uterine 14 wks 1/7 AOG,

not in labor.

Real-Time Reverse Transcription-Polymerase Chain Reaction (RT-PCR)

(+) NOVEL INFLUENZA A (H1) VIRAL RNA

INFLUENZA Acute respiratory illness caused by infection with

influenza viruses.

Affects the upper and/or lower respiratory tract and is often accompanied by systemic signs and symptoms: fever - headache myalgia - weakness

What is the Novel Influenza A (H1N1)?

Quadruple Reassortment 2 swine strains, 1 human strain, 1 avian strain of influenza

6 of 8 gene segments were similar to triple reassortant swine influenza viruses in pigs

1. Emergence of a Novel Swine-Origin Influenza A (H1N1)Virus in Humans. N Engl J Med 2009;3612. Epidemiology, clinical manifestations, and diagnosis of swine H1N1 influenza A. Uptodate, May 15, 2009

Antigenic Variation

Influenza A virus Subtypes

16 different HA antigens (H1 to H16) 9 different NA antigens (N1 to N9) 3 subtypes of HA (H1, H2, and H3) &

2 subtypes of NA (N1 and N2) – caused human disease.

found in birds & pigs

Immune responses to the H antigen are the major determinants of protection against infection with influenza virus.

N antigen limit viral spread and contribute to reduction of the infection.

Emergence of Antigenic Subtypes of Influenza A Virus Associated with Pandemic or Epidemic Disease

Years Subtype Extent of Outbreak

1889–90 H2N8a Severe pandemic

1900–03 H3N8a ?Moderate epidemic

1918–19 H1N1b (formerly HswN1) Severe pandemic

1933–35 H1N1b (formerly H0N1) Mild epidemic

1946–47 H1N1 Mild epidemic

1957–58 H2N2 Severe pandemic

1968–69 H3N2 Moderate pandemic

1977–78c H1N1 Mild pandemic

Late March and early April 2009 outbreak of H1N1 influenza A virus infection detected in Mexico several other countries

including the United States.

April 17, 2009 – CDC reported a novel H1N1 virus

The Western Pacific Region has reported a total 609 laboratory-confirmed cases of influenza A(H1N1): (WHO 5/29)

Japan 367 Australia 147 China 41 Republic of Korea 33 Zealand 9 Philippines 6 Singapore 4 Malaysia 2

Cumulative total as of 13 Aug 2009

  Cases* Deaths

WHO Regional Office for the Americas (AMRO) 105,882 1579

WHO Regional Office for the Western Pacific (WPRO) 27,111 50

WHO Regional Office for South-East Asia (SEARO) 13,172 106

WHO Regional Office for the Eastern Mediterranean (EMRO) 2532 8

WHO Regional Office for Africa (AFRO) 1469 3

Total 182,166 182,166 1,7461,746

Interspecies Transmission

Person-to-person Transmission

Droplets spray.

No risk from eating pork

Transmissibility - higher compared with seasonal influenza

Incubation period 

for most cases ranges from 1 to 4 days

Infectious - from 1 day prior to the development of signs and symptoms until resolution of fever

Contagious - until seven days after the onset of illness

Longer - in children (especially young infants), elderly adults, patients with chronic illnesses, and immunocompromised hosts.

Most common clinical findings (642 confirmed cases):1

Fever (94%) Cough (92%) Soar throat (66%) Diarrhea (25%) Vomiting (25%)

Influenza-Like Illness (ILI)2

fever plus cough and/or sore throat

1. Emergence of a Novel Swine-Origin Influenza A (H1N1)Virus in Humans. N Engl J Med 2009;3612. Epidemiology, clinical manifestations, and diagnosis of swine H1N1 influenza A. Uptodate, May 15, 20093 CIDRAP

Danger signs in all patients

shortness of breath dyspnea cyanosis bloody or coloured sputum chest pain altered mental status high fever that persists beyond 3 days hypotension

Complications

Progressive Pneumonia Respiratory Failure – cause of most deaths Acute Respiratory Distress Syndrome

* In the U.S., most described cases have been mild

Anna R Thorner, MD. Treatment and prevention of swine H1N1 influenza. Uptodate, May 14, 2009.

High Risk Groups for Complications

Children < 5 yrs. old > 50 years or older Children and adolescents

(age 6 months to 18 years) Pregnant women

Novel H1N1 Influenza (Swine Flu)http://www.cidrap.umn.edu/cidrap/content/influenza/swineflu/biofacts/swinefluoverview.html

High Risk Groups for Complications

Adults & children w/ chronic pulmonary, cardiovascular, hepatic, hematological, neurologic, neuromuscular, or metabolic disorders

Immunocompromised Adults & children Residents of nursing homes and other chronic-

care facilities.

Novel H1N1 Influenza (Swine Flu)http://www.cidrap.umn.edu/cidrap/content/influenza/swineflu/biofacts/swinefluoverview.html

DIAGNOSIS

DIAGNOSTIC TEST Real-Time Reverse Transcription-Polymerase

Chain Reaction (rRT-PCR) Detection Qualitative for Influenza A, B, H1, and H3 positive for influenza A and negative for H1 and

H3 If reactivity of real-time RT-PCR for influenza A is

strong (eg, Ct <30), it is more suggestive of a novel influenza A virus.

Novel H1N1 Influenza (Swine Flu)http://www.cidrap.umn.edu/cidrap/content/influenza/swineflu/biofacts/swinefluoverview.html

Tests Culture

Isolation of H1N1 influenza A virus - diagnostic too slow negative viral culture does not exclude H1N1

influenza A infection

* Priority for testing should be given to: Those who require hospitalization and Those who are at high risk for severe

complications

Specimen

Upper Respiratory sample Intubated - endotracheal aspirate Placed in viral transport media and placed

on ice (4ºC) or refrigerated or in a -70ºC freezer

CDC Case Definitions for Infection with Novel Influenza A (H1N1) Virus

Suspected case

does not meet the confirmed or probable case definition not novel H1N1 test–negative and is/has one of the following features:

Previously healthy, less than 65 years of age resides in a state without confirmed cases but has

traveled to a state or country where there is/are one or more confirmed or probable cases

has an epidemiologic link in the past 7 days to a confirmed case or probable case

cdc.com

CDC Case Definitions for Infection with Novel Influenza A (H1N1) Virus

Probable case

Influenza-like-illness positive for influenza A, but is unsubtypable by

reagents used to detect seasonal influenza virus infection

cdc.com

CDC Case Definitions for Infection with Novel Influenza A (H1N1) Virus

Confirmed case

Influenza-like-illness laboratory confirmed by one or more of

the following tests:• real-time RT-PCR

• viral culture

cdc.com

Antiviral Treatment and Prophylaxis of Influenza

  Age Group (years)

Antiviral Drug Children (       12)

Oseltamivir  

  Treatment, influenza A and B Age 1–12, dose varies by weighta

  Prophylaxis, influenza A and B Age 1–12, dose varies by weightb

Zanamivir  

  Treatment, influenza A and B Age 7–12, 10 mg bid by inhalation

  Prophylaxis, influenza A and B Age 5–12, 10 mg qd by inhalation

Amantadinec  

  Treatment, influenza A Age 1–9, 5 mg/kg in 2 divided doses, up to 150 mg/d

  Prophylaxis, influenza A Age 1–9, 5 mg/kg in 2 divided doses, up to 150 mg/d

Rimantadinec  

  Treatment, influenza A Not approved

  Prophylaxis, influenza A Age 1–9, 5 mg/kg in 2 divided doses, up to 150 mg/d

Recommended Treatment

supportive intravenous hydrations Antiviral agents

sensitive to oseltamivir and zanamivir  resistant to amantadine and rimantadine

Anna R Thorner, MD. Treatment and prevention of swine H1N1 influenza. Uptodate, May 14, 2009.

Oseltamivir (Tamiflu) Adult dose

Rx for acute illness: 75 mg PO bid for 5 d

Prophylaxis: 75 mg PO qd

available as 30-mg, 45-mg, and 75-mg oral capsules and as a powder for suspension that contains 12 mg/mL after reconstitution.

Zanamivir (Relenza) Adult dose

Rx for acute illness: 10 mg inhaled orally bid for 5 d

Prophylaxis of household contact: 10 mg inhaled orally qd for 10 d (initiate within 36 h)

Prophylaxis for community outbreak: 10 mg inhaled orally qd for 28 d (initiate within 5 d of outbreak)

powder form for inhalation via the Diskhaler oral inhalation device

Pregnant women

Oseltamivir and zanamivir are "Pregnancy Category C" medications

used only if the potential benefit justifies the potential risk to the embryo or fetus

cdc.com

Post-exposure antiviral prophylaxis

Close contacts who are at high risk for complications individuals with certain chronic medical

conditions ≥ 65 years of age pregnant women

cdc.com

Post-exposure antiviral prophylaxis

Health care workers, public health workers, or first responders who were not using appropriate personal protective equipment during close contact with a confirmed, probable, or suspected patient during that person's infectious period.

Pre-exposure prophylaxis

only be used in limited situations ongoing occupational risk for exposure

healthcare workers public health workers first responders

cdc.com

The single best way to protect against the flu is to get vaccinated each year.

flu shot— an inactivated

vaccine (containing killed virus). - for use in people older than 6 months, including healthy people and people with chronic medical conditions.

The nasal-spray flu vaccine —made with live, weakened flu viruses that do not cause the flu (LAIV or FluMist®). - approved for use in healthy* people, 2-49 y.o. who are not pregnant.

Each vaccine contains three influenza viruses: one A (H3N2) virus one A (H1N1) virus one B virus

2 weeks after vaccination - antibodies that provide protection against influenza virus infection develop in the body.

Influenza A H1N1 Vaccine Not yet available A European prototype of a swine flu vaccine

has been achieved Pandemic specific vaccines will not be

available until 4-6 months after a pandemic virus has emerged

Pandemic influenza vaccine manufacturing process & timeline

When to Get Vaccinated

Yearly flu vaccination should begin in September or as soon as vaccine is available and continue throughout the influenza season, into December, January, and beyond.

Timing & duration of influenza seasons vary. 

When H1N1 influenza is confirmed in a community (CDC recommends):

Home isolation School dismissal and childcare facility

closure Social distancing

Preventive measures for health care personnel

single-patient room with the door kept closed An airborne-infection isolation room with

negative-pressure air handling. Suctioning, bronchoscopy, or intubation should

be performed in a procedure room with negative-pressure air handling.

Patients should wear a surgical mask when outside their room.

Preventive measures for health care personnel

Frequently Hand washing & respiratory hygiene practices.

Routine cleaning and disinfection strategies Standard, droplet, and contact precautions

should be used for all patient care activities and maintained for 7 days after illness onset or until symptoms have resolved.

Preventive measures for health care personnel

Personnel providing care to or collecting clinical specimens from patients should wear disposable nonsterile gloves, gowns, and eye protection (eg, goggles) to prevent conjunctival exposure.

Preventive measures for health care personnel

personnel engaged in aerosol-generating activities (eg, collection of clinical specimens, endotracheal intubation, nebulizer treatment, bronchoscopy) and/or resuscitation involving emergency intubation or cardiac pulmonary resuscitation should wear a fit-tested disposable N95 respirator.

Preventions for the Community:

Cover the mouth & nose when coughing and sneezing.

Always wash hands with soap & water. Use alcohol-based hand sanitizers. Avoid close contact with sick people. Increase body resistance.

Travel Advisory

WHO is not recommending travel restrictions related to the outbreak of the influenza A(H1N1) virus

WHO do not believe entry and exit screenings would work to reduce the spread of this disease

 May 15, 2009 - CDC Travel Health Warning for Novel H1N1 Flu in Mexico Removed

Department Of Health

Oseltamivir (Tamiflu)

Designated referral centers2

National Referral Center Research Institute of Tropical Medicine (RITM)

Sub-national Referral Center Luzon & Metro Manila = San Lazaro Hospital Visayas = Vicente Sotto Memorial Medical

Center Mindanao = Davao Medical Center

1 Inquirer .net 2 DOH

DOH Lines of Defense

1. Points of Exit and Entry Screening2. Enhanced Diseases Surveillance3. Preventive Measures4. Prescribed Drug of Choice: Oseltamivir5. Infection Control (N95 mask)6. Social Distancing7. Emergency powers: Martial Law

DOH National Epidemiology Center

Thank You