Sw Ine Flu Final


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  • Family Orthomyxoviridae Genera: Influenza A, B, and C viruses based on antigenic characteristics of the nucleoprotein (NP) and matrix (M) protein antigens. Subtypes: surface hemagglutinin (H) & neuraminidase (N) antigens 16 distinct H subtypes & 9 distinct N subtypes . Influenza outbreaks are recorded virtually every year, although their extent and severity vary widely. Localized outbreaks take place at variable intervals, usually every 1–3 years. Influenza A epidemics begin abruptly, peak over a 2- to 3-week period, generally last for 2–3 months, and often subside almost as rapidly as they began.
  • majority of the genes similar to swine influenza viruses 2 genes were similar genes of swine influenza viruses of the Eurasian lineage
  • The most extensive and severe outbreaks are caused by influenza A viruses, in part because of the remarkable propensity of the H and N antigens of these viruses to undergo periodic antigenic variation Antigenic Drift - minor antigenic changes & occur frequently. antigenic drifts result from point mutations involving the RNA segment that codes for the hemagglutinin , (The hemagglutinin is the site by which the virus binds to sialic acid cell receptors, ) - accumulation of point mutations in the HA is linear, with each strain replacing the previously circulating one These types of antigenic variation may involve the hemagglutinin alone or both the hemagglutinin and the neuraminidase. whereas the neuraminidase degrades the receptor and plays a role in the release of the virus from infected cells after replication has taken place.)
  • Antigenic Shift Major antigenic variations may be associated with pandemics and are restricted to influenza A viruses “ new” viruses to which the population has no immunity.
  • Hemagglutinin (HA) Antigenic sites and binds to sialic acid receptor cells. Neuraminidase (NA) enzyme that catalyzes the removal of terminal sialic acids ( N -acetyl neuraminic acid) or degrades the receptors to release of the virus from infected cells after replication has taken place.
  • a As determined by retrospective serologic survey of individuals alive during those years ("seroarcheology"). b Hemagglutinins formerly designated as Hsw and H0 are now classified as variants of H1. c From this time until the present (2006–2007), viruses of the H1N1 and H3N2 subtypes have circulated either in alternating years or concurrently. H1N1 viruses circulated from 1918 to 1956; thus, individuals born prior to 1957 would be expected to have some degree of immunity to H1N1 viruses. During most outbreaks of influenza A, a single subtype has circulated at a time. However, since 1977, H1N1 and H3N2 viruses have circulated simultaneously, resulting in outbreaks of varying severity only H1, H2, H3, N1, and N2 have been associated with epidemics of disease in humans. Influenza B and C viruses are similarly designated. Influenza A and B viruses most extensively studied morphologically similar major human pathogens 16 different HA antigens (H1 to H16) 9 different NA antigens (N1 to N9) three subtypes of HA (H1, H2, and H3) and two subtypes of NA (N1 and N2) – caused human disease. found in birds & pigs
  • 17 May 2009, 39 countries have officially reported 8480 cases of influenza A(H1N1) infection. Mexico has reported 2895 laboratory confirmed human cases of infection, including 66 deaths. The United States has reported 4714 laboratory confirmed human cases, including four deaths. Canada has reported 496 laboratory confirmed human cases, including one death. Costa Rica has reported nine laboratory confirmed human cases, including one death. Current epidemiological models project that a pandemic could result in two to 7.4 million deaths globally.
  • On April 29, 2009, the World Health Organization raised its pandemic alert level to phase 5, indicating that there is sustained person-to-person spread in at least two countries [ 8 ]. This designation implies that a pandemic is imminent and that the time to finalize the organization, communication, and implementation of the planned mitigation measures is short.
  • Pigs may play an important role in interspecies transmission of influenza virus. Susceptible pig cells possess receptors for both avian and human influenza strains, which allow for the reassortment of influenza virus genes from different species if a pig cell is infected with more than one strain
  • Manifestations of H1N1 influenza (swine flu) are similar to those of seasonal influenza. Patients present with symptoms of acute respiratory illness, including at least 2 of the following: Fever Cough Sore throat Body aches Headache Chills and fatigue Diarrhea and vomiting (possible) Persons with these symptoms should call their health care provider promptly. If an antiviral agent is warranted, it should ideally be initiated with 48 hours from the onset of symptoms (see  Medications ). The duration of illness is typically 4-6 days. The infectious period for a confirmed case is defined as 1 day prior to the onset of symptoms to 7 days after onset. In children, signs of severe disease include apnea, tachypnea, dyspnea, cyanosis, dehydration, altered mental status, and extreme irritability. 13
  • Clinicians, patients, and those providing home-based care need to be alert to danger signs that can signal progression to more severe disease. As progression can be very rapid, medical attention should be sought when any of the following danger signs appear in a person with confirmed or suspected H1N1 infection: In children , danger signs include fast or difficult breathing, lack of alertness, difficulty in waking up, and little or no desire to play.
  • Immunocompromised Adults & children- cancer patients, HIV/ AIDS pt Adults and children who have required regular medical follow-up or hospitalization during the preceding year because of chronic metabolic diseases (including diabetes mellitus), renal dysfunction, hemoglobinopathies, or immunodeficiency (including immunodeficiency caused by medications or by HIV) Persons who live with or care for persons at high risk for influenza-related complications, including healthy household contacts of and caregivers for children from birth through 59 months of age Health care workers
  • Upper Respiratory sample (nasopharyngeal swab, nasal swab, throat swab, combined oropharyngeal/nasopharyngeal swab, or nasal aspirate)
  • a <15 kg: 30 mg bid; >15–23 kg: 45 mg bid; >23–40 kg: 60 mg bid; >40 kg: 75 mg bid. b <15 kg: 30 mg qd; >15–23 kg: 45 mg qd; >23–40 kg: 60 mg qd; >40 kg: 75 mg qd. c Amantadine and rimantadine are not currently recommended (2006–2007) because of widespread resistance in influenza A/H3N2 viruses. Oseltamivir (administered orally at a dose of 75 mg twice a day for 5 days) or zanamivir (which must be given by an oral inhalation device; 10 mg twice a day for 5 days) reduces the duration of signs and symptoms of influenza by 1–1.5 days if treatment is started within 2 days of the onset of illness.
  • WHO recommends prompt antiviral treatment for children with severe or deteriorating illness, and those at risk of more severe or complicated illness. This recommendation includes all children under the age of five years, as this age group is at increased risk of more severe illness.
  • oseltamivir has been associated with nausea and vomiting, whose frequency can be reduced by administration of the drug with food. Oseltamivir has also been associated with neuropsychiatric side effects in children.
  • Zanamivir may exacerbate bronchospasm in asthmatic patients
  • WHO recommends that pregnant women receive antiviral treatment as soon as possible after symptom onset.
  • The viruses in the vaccine change each year based on international surveillance and scientists' estimations about which types and strains of viruses will circulate in a given year.
  • Vaccines to prevent the 2009 H1N1 virus have not yet been licensed; however, initial doses of licensed vaccine are expected to be available by mid-October 2009
  • Activities at WHO Collaborating Centers Identification of a new virus: network surveillance-, laboratories around the world routinely collect samples of circulating influenza viruses and submit these to WHO Collaborating Centres for Reference and Research on Influenza for analysis. The first step towards the production of a pandemic vaccine starts when a Centre detects a novel influenza virus that differs significantly from circulating strains and reports this finding to WHO. Vaccine virus is grown in eggs because the flu virus grows well in them, and eggs are readily available. 2. Preparation of the vaccine strain (called vaccine virus): To make the vaccine virus less dangerous and better able to grow in hen’s eggs (the production method used by most manufacturers), the virus is mixed with a standard laboratory virus strain and the two are allowed to grow together. After a while, a hybrid is formed which contains the inner components of the laboratory strain, and the outer components of the pandemic strain. It takes roughly three weeks to prepare the hybrid virus. 3. Verification of the vaccine strain: the hybrid virus needs to be tested to make sure that it truly produces the outer proteins of the pandemic strain, is safe and grows in eggs. Upon completion of this process, which takes roughly another three weeks , the vaccine strain is distributed to vaccine manufacturers. 4. Preparation of reagents to test the vaccine (with reference reagents): In parallel, WHO Collaborating Centres produce standardized substances (called reagents) that are given to all vaccine manufacturers to enable them to measure how much virus they are producing, and to ensure they are all packaging the correct dose of vaccine. This requires at least three months and often represents a bottleneck for manufacturers. Activities at vaccine manufacturers 1. Optimization of virus growth conditions: The vaccine manufacturer takes the hybrid vaccine virus that it has received from the WHO laboratories, and tests different growth conditions in eggs to find the best conditions. This process requires roughly three weeks . 2. Vaccine bulk manufacture: For most influenza vaccine production, this is performed in nine to twelve-days old fertilized hen's eggs . The vaccine virus is injected into thousands of eggs, and the eggs are then incubated for two to three days during which time the virus multiplies. The egg white, which now contains many millions of vaccine viruses, is then harvested, and the virus is separated from the egg white. The partially pure virus is killed with chemicals. The outer proteins of the virus are then purified and the result is several hundred or thousand liters of purified virus protein that is referred to as antigen, the active ingredient in the vaccine. Producing each batch, or lot, of antigen takes approximately two weeks, and a new batch can be started every few days. The size of the batch depends on how many eggs a manufacturer can obtain, inoculate and incubate. Another factor is the yield per egg. When one batch has been produced, the process is repeated as often as needed to generate the required amount of vaccine. 3. Quality control: This can only begin once the reagents for testing the vaccine are supplied by WHO laboratories, as described above. Each batch is tested and the sterility of bulk antigen is verified. This process takes two weeks . 4. Vaccine filling and release: The batch of vaccine is diluted to give the desired concentration of antigen, and put into vials or syringes, and labeled. A number of these are then tested: for sterility to confirm the protein concentration and for safety by testing in animals. This process takes two weeks . 5. Clinical studies: In certain countries, each new influenza vaccine has to be tested in a few people to show that it performs as expected . This requires at least four weeks . In some countries this may not be required as many clinical trials were done with similar annual vaccine preparation, and the assumption is that the new pandemic vaccine will behave similarly. Activities at regulatory agencies - regulatory approval Before the vaccine can be sold or administered to people, regulatory approval is required. Each country has its own regulatory agency and rules. If the vaccine is made with the same processes as the seasonal influenza vaccine, and in the same manufacturing plant, this can be very rapid (one to two days). Regulatory agencies in some countries may require clinical testing before approving the vaccine, which adds to the time before the vaccine is available. The full process, in a best case scenario, can be completed in five to six months. Then the first final pandemic vaccine lot would be available for distribution and use.
  • While influenza outbreaks can happen as early as October, most of the time influenza activity peaks in January or later.  
  • Home isolation Patients who develop flulike illness (ie, fever with either cough or sore throat) should be strongly encouraged to self-isolate in their home for 7 days after the onset of illness or at least 24 hours after symptoms have resolved, whichever is longer. To seek medical care, patient should contact their health care providers to report illness (by telephone or other remote means) before seeking care at a clinic, physician's office, or hospital. Patients who have difficulty breathing or shortness of breath or who are believed to be severely ill should seek immediate medical attention. If the patient must go into the community (eg, to seek medical care), he or she should wear a face mask to reduce the risk of spreading the virus in the community when coughing, sneezing, talking, or breathing. If a face mask is unavailable, ill persons who need to go into the community should use tissues to cover their mouth and nose while coughing. While in home isolation, patients and other household members should be given infection control instructions, including frequent hand washing with soap and water. Use alcohol-based hand gels (containing at least 60% alcohol) when soap and water are not available and hands are not visibly dirty. Patients with H1N1 influenza should wear a face mask when within 6 feet of others at home. Household contacts who are not ill Remain home at the earliest sign of illness. Minimize contact in the community to the extent possible. Designate a single household family member as caregiver for the patient to minimize interactions with asymptomatic persons. School dismissal and childcare facility closure Strong consideration should be given to close schools upon a confirmed case of H1N1 flu or a suspected case epidemiologically linked to a confirmed case. Decisions regarding broader school dismissal within these communities should be left to local authorities, taking into account the extent of influenzalike illness within the community. Cancelation of all school or childcare related gatherings should also be announced. Encourage parents and students to avoid congregating outside of the school if school is canceled. Duration of schools and childcare facilities closings should be evaluated on an ongoing basis depending on epidemiological findings. Consultation with local or state health departments is essential for guidance concerning when to reopen schools. If no additional confirmed or suspected cases are identified among students (or school-based personnel) for a period of 7 days, schools may consider reopening. Schools and childcare facilities in unaffected areas should begin preparation for possible school closure. Social distancing Large gatherings linked to settings or institutions with laboratory-confirmed cases should be canceled (eg, sporting events or concerts linked to a school with cases); other large gatherings in the community may not need to be canceled at this time. Additional social distancing measures are currently not recommended. Persons with underlying medical conditions who are at high risk for complications of influenza should consider avoiding large gatherings.
  • Increase body resistance: -have at least 8 hrs of sleep. -be physically active -drink plenty of fluids. -eat nutritious foods.
  • Sw Ine Flu Final

    1. 1. INFLUENZA A (H1N1) LIZA D. MARIPOSQUE, M.D. 2nd Year Family Med Resident Perpetual Succour Hospital September 2009
    2. 2. OBJECTIVES: <ul><li>To present a case of H1N1 in a 28 years old pregnant patient. </li></ul><ul><li>To discuss Influenza A H1N1 </li></ul><ul><ul><li>Epidemiology </li></ul></ul><ul><ul><li>Signs & symptoms </li></ul></ul><ul><ul><li>Risk factors </li></ul></ul><ul><ul><li>Diagnosis </li></ul></ul><ul><ul><li>Treatment and Prevention </li></ul></ul>
    3. 3. <ul><li>J. L., 28 years old, pregnant </li></ul><ul><li>G 4 P 1-1-1-2 , 13 wks 6/7 days AOG by LMP </li></ul><ul><li>Married </li></ul><ul><li>Filipino </li></ul><ul><li>Roman Catholic </li></ul><ul><li>Sambag I, Cebu City </li></ul><ul><li>admitted for the 4 th times at PSH </li></ul><ul><li>CC: fever, cough & shortness of breath </li></ul>
    4. 4. PAST MEDICAL HISTORY <ul><li>Non-diabetic, non-hypertensive, </li></ul><ul><li>non-asthmatic. </li></ul><ul><li>Non-smoker, non-alcohol beverage drinker </li></ul><ul><li>Allergy: shrimp </li></ul><ul><li>HFD: HPN, DM 2, Bronchial Asthma </li></ul>
    5. 5. PAST MEDICAL HISTORY <ul><li>2004 – PSH : NSVD (PT) </li></ul><ul><li>2005 – PSH : Ectopic pregnancy, </li></ul><ul><li> S/P Salpingectomy R </li></ul><ul><li>2008 – PSH : NSVD (FT) </li></ul><ul><li>2 wks PTA : Herpes Zoster infection </li></ul>
    6. 6. OBSTETRICAL HISTORY <ul><li>Menarche - 10 y.o x 28 days cycle </li></ul><ul><li>7 days duration </li></ul><ul><li>LMP: April 1, 2009 </li></ul><ul><li>AOG: 13 wks & 6 days </li></ul><ul><li>EDC: January 8, 2010 </li></ul>
    7. 7. HISTORY OF PRESENT ILLNESS <ul><li>3 days PTA, sudden onset of fever with cough, coryza, headache & poor appetite. </li></ul><ul><li>Night PTA, had shortness of breath and spontaneously resolved, but recurred in the morning PTA thus prompted admission. </li></ul>
    8. 8. PHYSICAL EXAMINATIONS <ul><li>Examined conscious, coherent & slightly respiratory distress. </li></ul><ul><li>BP: 110/80 mmHg HR: 86 bpm </li></ul><ul><li>RR: 29 cpm T: 36.8 0 C </li></ul><ul><li>Wt: 59.8 kg </li></ul>
    9. 9. PHYSICAL EXAMINATION <ul><li>SKIN : Fair, warm, no rashes, no cyanosis </li></ul><ul><li>HEENT : Anecteric sclerae, pinkish palpebral conjunctivae, nasal congestion , non-hyperemic tonsils. </li></ul><ul><li>NECK : No lymphadenopathy </li></ul><ul><li>C/L : Equal chest expansion, clear breath sounds, no rales, no wheeze. </li></ul>
    10. 10. PHYSICAL EXAMINATION <ul><li>ABDOMEN : Flabby, normoactive bowel sound, soft, nontender, </li></ul><ul><li>no hepatomegaly, no palpable mass. </li></ul><ul><li>GUT : fundus 4 fingerbreaths below umbilicus, FHT: 139 bpm, (-) KPS </li></ul><ul><li>EXT . : No edema, strong pulses, CRT <2 sec. </li></ul><ul><li>CNS : WNL </li></ul>
    11. 11. ADMITTING IMPRESSION <ul><li>Upper Respiratory Tract Infection </li></ul><ul><li>PU 13 wks 6/7 AOG, Not in labor </li></ul>
    12. 12. COURSE IN THE WARD <ul><li>1 ST HOSPITAL DAY </li></ul><ul><li>P : Cough, fever, coryza, shortness of breath </li></ul><ul><li>S : w/ cough, w/ coryza </li></ul><ul><li>O : conscious, coherent & not in respiratory </li></ul><ul><li>distress. </li></ul><ul><li>BP: 100/70-110/80 mmHg PR: 76-85 bpm RR: 19-29 cpm T: 36.9-37.5 0 C </li></ul>
    13. 13. COURSE IN THE WARD <ul><li>1 ST HOSPITAL DAY </li></ul><ul><li>SKIN : Fair, warm, no rashes. </li></ul><ul><li>HEENT : Anecteric sclerae, pinkish palpebral conjunctivae, with both nasal congestion , non-hyperemic tonsils. </li></ul><ul><li>NECK : No lymphadenopathy </li></ul><ul><li>C/L : Equal chest expansion, clear breath sound, no rales, </li></ul><ul><li>no wheeze. </li></ul><ul><li>ABDOMEN : Flabby, normoactive bowel sounds, soft, nontender, no hepatomegaly, no mass. </li></ul><ul><li>GUT : fundus 4 fingerbreaths below umbilicus </li></ul><ul><li> FHT: 139-160 bpm, (-) KPS </li></ul><ul><li>EXT . : No edema, strong pulses, CRT <2 sec. </li></ul><ul><li>CNS : WNL </li></ul>
    14. 14. COURSE IN THE WARD <ul><li>1 ST HOSPITAL DAY </li></ul><ul><li>A : Influenza A </li></ul><ul><li>R/O Influenza H1N1 </li></ul><ul><li>Pregnancy Uterine 13 wks 6/7 AOG, not in labor </li></ul>
    15. 15. COURSE IN THE WARD <ul><li>1 ST HOSPITAL DAY </li></ul><ul><li>P : > Oxygen inhalation. </li></ul><ul><li> > IVF started. </li></ul><ul><li> > Hypoallergenic diet. </li></ul><ul><li> > Labs: CBC, U/A, CXR w/ abdominal shield, </li></ul><ul><li> Screening test for Influenza A & B </li></ul>
    16. 16. LABORATORY RESULTS 235 140-440 plt 38.7 36-46% Hct 13.2 12-16 Hb 1 2-4% Basophil 1 0-5% Eosinophil 10 2-11% Monocytes 16 13-40% Lymphocytes 72 47-80% Neutrophils 6.42 4-11.30 WBC RESULTS N.V. CBC
    17. 17. rare Amorphous material rare Bacteria abundant Mucus Threads rare Epithelial cells 0-2 / hpf WBC/hpf 5-10 / hpf RBC/hpf + Urine Ketone 6 pH + Protein NEG Glucose Yellow, clear Color & transparency RESULTS URINALYSIS
    18. 18. <ul><li>(Rapid Qualitative Test) </li></ul><ul><li>Sample Type: Nasopharyngeal Swab </li></ul><ul><li>Results: ( + ) Influenza A </li></ul><ul><li> (-) Influenza B </li></ul>SCREENING TEST FOR INFLUENZA A & B
    19. 19. COURSE IN THE WARD <ul><li>1 ST HOSPITAL DAY </li></ul><ul><li>P : >FHT monitoring BID. </li></ul><ul><li>> Paracetamol 500 mg 4H prn for T≥38 0 C & headache. </li></ul><ul><li>> Sinupret 1 tab TID then revise to BID. </li></ul><ul><li>> Salbutamol 1 neb q 6H. </li></ul><ul><li>> Vit. C (Benutrex) 1 amp infused to present IVF ANST and in succeeding IVF to follow. </li></ul><ul><li>> Prenatal Vit. (Beniforte) 1 cap OD is continued. </li></ul><ul><li>> co-managed with OB. </li></ul>
    20. 20. COURSE IN THE WARD <ul><li>2 nd Hospital Day </li></ul><ul><li>S : no complaints </li></ul><ul><li>O : BP: 100/70-120/80 mmHg </li></ul><ul><li>PR: 77-91 bpm </li></ul><ul><li>RR: 18-20 cpm </li></ul><ul><li>T: 36.7-37 0 C </li></ul>
    21. 21. COURSE IN THE WARD <ul><li>2 nd Hospital Day </li></ul><ul><li>SKIN : Fair, warm, no rashes. </li></ul><ul><li>HEENT : Anecteric sclerae, pinkish palpebral conjunctivae, </li></ul><ul><li> no nasal congestion , non-hyperemic tonsils. </li></ul><ul><li>NECK : No lymphadenopathy </li></ul><ul><li>C/L : Equal chest expansion, clear breath sounds, no rales, </li></ul><ul><li> no wheeze. </li></ul><ul><li>ABDOMEN : Flabby, normoactive bowel sound, soft, nontender, no hepatomegaly, no mass. </li></ul><ul><li>GUT : fundus 4 fingerbreaths below umbilicus, </li></ul><ul><li>FHT: 150-159 bpm , (-) KPS </li></ul><ul><li>EXT . : No edema, strong pulses, CRT <2 sec. </li></ul><ul><li>CNS : WNL </li></ul>
    22. 22. COURSE IN THE WARD <ul><li>2 nd Hospital Day </li></ul><ul><li>P: > Confirmatory throat swab test for Influenza A H1N1 c/o DOH. </li></ul><ul><li>> IVF terminated. </li></ul><ul><li>> meds given. </li></ul>
    23. 23. COURSE IN THE WARD <ul><li>3 rd Hospital Day </li></ul><ul><li>S : No complaints </li></ul><ul><li>O : BP: 100/70-120/70 mmHg PR: 74-75 bpm RR: 18-19 cpm T: 36.4-36.7 0 C </li></ul>
    24. 24. COURSE IN THE WARD <ul><li>3rd Hospital Day </li></ul><ul><li>SKIN : Fair, warm, no rashes. </li></ul><ul><li>HEENT : Anecteric sclerae, pinkish palpebral conjunctivae, no nasal congestion , non-hyperemic tonsils. </li></ul><ul><li>NECK : No lymphadenopathy </li></ul><ul><li>C/L : Equal chest expansion, clear breath sounds , no rales, no wheeze. </li></ul><ul><li>ABDOMEN : Flabby, normoactive bowel sound, soft, nontender, no hepatomegaly, no mass. </li></ul><ul><li>GUT : fundus 4 fingerbreaths below umbilicus </li></ul><ul><li> FHT: 149-150 bpm, (-) KPS </li></ul><ul><li>EXT . : No edema, strong pulses, CRT <2 sec. </li></ul><ul><li>CNS : WNL </li></ul>
    25. 25. COURSE IN THE WARD <ul><li>3rd Hospital Day </li></ul><ul><li>A: > condition improved </li></ul><ul><li>> Patient discharge. </li></ul><ul><li> > Take home meds: </li></ul><ul><li>1. Bisolvon syr. 1 tbsp TID x 1 wk </li></ul><ul><li>2. Multivit. (Centrum) 1 cap OD </li></ul><ul><li>3. Beniforte 1 cap OD. </li></ul><ul><li> > Encourage oral fluid intake. </li></ul><ul><li> > ff-up with AP 1 wk after discharge. </li></ul>
    26. 26. COURSE IN THE WARD <ul><li>3rd Hospital Day </li></ul><ul><li>Final Diagnoses: </li></ul><ul><ul><li>Influenza A H1N1 </li></ul></ul><ul><ul><li>Pregnancy Uterine 14 wks 1/7 AOG, </li></ul></ul><ul><ul><ul><li>not in labor. </li></ul></ul></ul>
    27. 27. <ul><li>Real-Time Reverse Transcription-Polymerase Chain Reaction (RT-PCR) </li></ul><ul><li>( + ) NOVEL INFLUENZA A (H1) VIRAL RNA </li></ul>
    28. 28. INFLUENZA <ul><li>Acute respiratory illness caused by infection with influenza viruses. </li></ul><ul><li>Affects the upper and/or lower respiratory tract and is often accompanied by systemic signs and symptoms: </li></ul><ul><ul><li>fever - headache </li></ul></ul><ul><ul><li>myalgia - weakness </li></ul></ul>
    29. 29. What is the Novel Influenza A (H1N1)? <ul><li>Quadruple Reassortment </li></ul><ul><ul><ul><li>2 swine strains, </li></ul></ul></ul><ul><ul><ul><li>1 human strain, </li></ul></ul></ul><ul><ul><ul><li>1 avian strain of influenza </li></ul></ul></ul><ul><li>6 of 8 gene segments were similar to triple reassortant swine influenza viruses in pigs </li></ul>1. Emergence of a Novel Swine-Origin Influenza A (H1N1) Virus in Humans. N Engl J Med 2009;361 2. Epidemiology, clinical manifestations, and diagnosis of swine H1N1 influenza A. Uptodate, May 15, 2009
    30. 30. Antigenic Variation
    31. 32. Influenza A virus Subtypes <ul><li>16 different HA antigens (H1 to H16) </li></ul><ul><li>9 different NA antigens (N1 to N9) </li></ul><ul><li>3 subtypes of HA (H1, H2, and H3) & </li></ul><ul><li>2 subtypes of NA (N1 and N2) – caused human disease. </li></ul><ul><li>found in birds & pigs </li></ul>
    32. 33. <ul><li>Immune responses to the H antigen are the major determinants of protection against infection with influenza virus. </li></ul><ul><li>N antigen limit viral spread and contribute to reduction of the infection. </li></ul>
    33. 34. Emergence of Antigenic Subtypes of Influenza A Virus Associated with Pandemic or Epidemic Disease Mild pandemic H1N1 1977–78 c Moderate pandemic H3N2 1968–69 Severe pandemic H2N2 1957–58 Mild epidemic H1N1 1946–47 Mild epidemic H1N1 b (formerly H0N1) 1933–35 Severe pandemic H1N1 b (formerly HswN1) 1918–19 ?Moderate epidemic H3N8 a 1900–03 Severe pandemic H2N8 a 1889–90 Extent of Outbreak Subtype Years
    34. 35. <ul><li>Late March and early April 2009 </li></ul><ul><ul><li>outbreak of H1N1 influenza A virus infection </li></ul></ul><ul><ul><li>detected in Mexico  several other countries including the United States. </li></ul></ul><ul><li>April 17, 2009 – CDC reported a novel H1N1 virus </li></ul>
    35. 37. The Western Pacific Region has reported a total 609 laboratory-confirmed cases of influenza A(H1N1): (WHO 5/29) <ul><li>Japan 367 </li></ul><ul><li>Australia 147 </li></ul><ul><li>China 41 </li></ul><ul><li>Republic of Korea 33 </li></ul><ul><li>Zealand 9 </li></ul><ul><li>Philippines 6 </li></ul><ul><li>Singapore 4 </li></ul><ul><li>Malaysia 2 </li></ul>
    36. 38. 1579 105,882 WHO Regional Office for the Americas (AMRO) 1,746 182,166 Total 3 1469 WHO Regional Office for Africa (AFRO) 8 2532 WHO Regional Office for the Eastern Mediterranean (EMRO) 106 13,172 WHO Regional Office for South-East Asia (SEARO) 50 27,111 WHO Regional Office for the Western Pacific (WPRO) Deaths Cases*   Cumulative total as of 13 Aug 2009
    37. 40. Interspecies Transmission
    38. 41. Person-to-person Transmission   <ul><li>Droplets spray. </li></ul><ul><li>No risk from eating pork </li></ul><ul><li>Transmissibility - higher compared with seasonal influenza </li></ul>
    39. 42. <ul><li>Incubation period   </li></ul><ul><ul><li>for most cases ranges from 1 to 4 days </li></ul></ul>
    40. 43. <ul><ul><li>Infectious - from 1 day prior to the development of signs and symptoms until resolution of fever </li></ul></ul><ul><ul><li>Contagious - until seven days after the onset of illness </li></ul></ul><ul><ul><li>Longer - in children (especially young infants), elderly adults, patients with chronic illnesses, and immunocompromised hosts. </li></ul></ul>
    41. 44. <ul><li>Most common clinical findings (642 confirmed cases): 1 </li></ul><ul><ul><li>Fever (94%) </li></ul></ul><ul><ul><li>Cough (92%) </li></ul></ul><ul><ul><li>Soar throat (66%) </li></ul></ul><ul><ul><li>Diarrhea (25%) </li></ul></ul><ul><ul><li>Vomiting (25%) </li></ul></ul><ul><li>Influenza-Like Illness (ILI) 2 </li></ul><ul><ul><li>fever plus cough and/or sore throat </li></ul></ul>1. Emergence of a Novel Swine-Origin Influenza A (H1N1) Virus in Humans. N Engl J Med 2009;361 2. Epidemiology, clinical manifestations, and diagnosis of swine H1N1 influenza A. Uptodate, May 15, 2009 3 CIDRAP
    42. 45. Danger signs in all patients <ul><li>shortness of breath </li></ul><ul><li>dyspnea </li></ul><ul><li>cyanosis </li></ul><ul><li>bloody or coloured sputum </li></ul><ul><li>chest pain </li></ul><ul><li>altered mental status </li></ul><ul><li>high fever that persists beyond 3 days </li></ul><ul><li>hypotension </li></ul>
    43. 46. Complications <ul><li>Progressive Pneumonia </li></ul><ul><li>Respiratory Failure – cause of most deaths </li></ul><ul><li>Acute Respiratory Distress Syndrome </li></ul><ul><li>* In the U.S., most described cases have been mild </li></ul>Anna R Thorner, MD. Treatment and prevention of swine H1N1 influenza. Uptodate, May 14, 2009.
    44. 47. High Risk Groups for Complications <ul><li>Children < 5 yrs. old </li></ul><ul><li>> 50 years or older </li></ul><ul><li>Children and adolescents </li></ul><ul><li> (age 6 months to 18 years) </li></ul><ul><li>Pregnant women </li></ul>Novel H1N1 Influenza (Swine Flu) http://www.cidrap.umn.edu/cidrap/content/influenza/swineflu/biofacts/swinefluoverview.html
    45. 48. High Risk Groups for Complications <ul><li>Adults & children w/ chronic pulmonary, cardiovascular, hepatic, hematological, neurologic, neuromuscular, or metabolic disorders </li></ul><ul><li>Immunocompromised Adults & children </li></ul><ul><li>Residents of nursing homes and other chronic-care facilities. </li></ul>Novel H1N1 Influenza (Swine Flu) http://www.cidrap.umn.edu/cidrap/content/influenza/swineflu/biofacts/swinefluoverview.html
    46. 49. DIAGNOSIS
    47. 50. DIAGNOSTIC TEST <ul><li>Real-Time Reverse Transcription-Polymerase Chain Reaction (rRT-PCR) Detection </li></ul><ul><ul><li>Qualitative for Influenza A, B, H1, and H3 </li></ul></ul><ul><ul><li>positive for influenza A and negative for H1 and H3 </li></ul></ul><ul><ul><li>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. </li></ul></ul>Novel H1N1 Influenza (Swine Flu) http://www.cidrap.umn.edu/cidrap/content/influenza/swineflu/biofacts/swinefluoverview.html
    48. 51. Tests <ul><li>Culture </li></ul><ul><ul><li>Isolation of H1N1 influenza A virus - diagnostic </li></ul></ul><ul><ul><li>too slow </li></ul></ul><ul><ul><li>negative viral culture does not exclude H1N1 influenza A infection </li></ul></ul><ul><li>* Priority for testing should be given to: </li></ul><ul><ul><li>Those who require hospitalization and </li></ul></ul><ul><ul><li>Those who are at high risk for severe complications </li></ul></ul>
    49. 52. Specimen <ul><li>Upper Respiratory sample </li></ul><ul><li>Intubated - endotracheal aspirate </li></ul><ul><li>Placed in viral transport media and placed on ice (4ºC) or refrigerated or in a -70ºC freezer </li></ul>
    50. 53. CDC Case Definitions for Infection with Novel Influenza A (H1N1) Virus <ul><li>Suspected case </li></ul><ul><ul><li>does not meet the confirmed or probable case definition </li></ul></ul><ul><ul><li>not novel H1N1 test–negative </li></ul></ul><ul><ul><li>and is/has one of the following features: </li></ul></ul><ul><ul><ul><li>Previously healthy, less than 65 years of age </li></ul></ul></ul><ul><ul><ul><li>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 </li></ul></ul></ul><ul><ul><ul><li>has an epidemiologic link in the past 7 days to a confirmed case or probable case </li></ul></ul></ul>cdc.com
    51. 54. CDC Case Definitions for Infection with Novel Influenza A (H1N1) Virus <ul><li>Probable case </li></ul><ul><ul><li>Influenza-like-illness </li></ul></ul><ul><ul><li>positive for influenza A, but is unsubtypable by reagents used to detect seasonal influenza virus infection </li></ul></ul>cdc.com
    52. 55. CDC Case Definitions for Infection with Novel Influenza A (H1N1) Virus <ul><li>Confirmed case </li></ul><ul><ul><li>Influenza-like-illness </li></ul></ul><ul><ul><li>laboratory confirmed by one or more of the following tests: </li></ul></ul><ul><ul><ul><li>• real-time RT-PCR </li></ul></ul></ul><ul><ul><ul><li>• viral culture </li></ul></ul></ul>cdc.com
    53. 56. Antiviral Treatment and Prophylaxis of Influenza Age 1–9, 5 mg/kg in 2 divided doses, up to 150 mg/d    Prophylaxis, influenza A Not approved    Treatment, influenza A   Rimantadine c 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    Treatment, influenza A   Amantadinec Age 5–12, 10 mg qd by inhalation    Prophylaxis, influenza A and B Age 7–12, 10 mg bid by inhalation    Treatment, influenza A and B   Zanamivir Age 1–12, dose varies by weight b    Prophylaxis, influenza A and B Age 1–12, dose varies by weight a     Treatment, influenza A and B   Oseltamivir Children (        12) Antiviral Drug Age Group (years)  
    54. 57. Recommended Treatment <ul><li>supportive </li></ul><ul><li>intravenous hydrations </li></ul><ul><li>Antiviral agents </li></ul><ul><ul><li>sensitive to oseltamivir  and  zanamivir   </li></ul></ul><ul><ul><li>resistant to amantadine and rimantadine </li></ul></ul>Anna R Thorner, MD. Treatment and prevention of swine H1N1 influenza. Uptodate, May 14, 2009.
    55. 58. Oseltamivir (Tamiflu) <ul><li>Adult dose </li></ul><ul><ul><li>Rx for acute illness: 75 mg PO bid for 5 d </li></ul></ul><ul><ul><li>Prophylaxis: 75 mg PO qd </li></ul></ul><ul><li>available as 30-mg, 45-mg, and 75-mg oral capsules and as a powder for suspension that contains 12 mg/mL after reconstitution. </li></ul>
    56. 59. Zanamivir (Relenza) <ul><li>Adult dose </li></ul><ul><ul><li>Rx for acute illness: 10 mg inhaled orally bid for 5 d </li></ul></ul><ul><ul><li>Prophylaxis of household contact: 10 mg inhaled orally qd for 10 d (initiate within 36 h) </li></ul></ul><ul><ul><li>Prophylaxis for community outbreak: 10 mg inhaled orally qd for 28 d (initiate within 5 d of outbreak) </li></ul></ul><ul><li>powder form for inhalation via the Diskhaler oral inhalation device </li></ul>
    57. 60. Pregnant women <ul><li>Oseltamivir and zanamivir are &quot;Pregnancy Category C&quot; medications </li></ul><ul><li>used only if the potential benefit justifies the potential risk to the embryo or fetus </li></ul>cdc.com
    58. 61. Post-exposure antiviral prophylaxis <ul><li>Close contacts who are at high risk for complications </li></ul><ul><ul><li>individuals with certain chronic medical conditions </li></ul></ul><ul><ul><li>≥ 65 years of age </li></ul></ul><ul><ul><li>pregnant women </li></ul></ul>cdc.com
    59. 62. Post-exposure antiviral prophylaxis <ul><li>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. </li></ul>
    60. 63. Pre-exposure prophylaxis <ul><li>only be used in limited situations </li></ul><ul><li>ongoing occupational risk for exposure </li></ul><ul><ul><li>healthcare workers </li></ul></ul><ul><ul><li>public health workers </li></ul></ul><ul><ul><li>first responders </li></ul></ul>cdc.com
    61. 64. The single best way to protect against the flu is to get vaccinated each year. <ul><li>flu shot </li></ul><ul><ul><li>— an inactivated vaccine (containing killed virus). - for use in people older than 6 months, including healthy people and people with chronic medical conditions. </li></ul></ul><ul><li>The nasal-spray flu vaccine </li></ul><ul><li>— made with live, weakened flu viruses that do not cause the flu (LAIV or FluMist®). </li></ul><ul><li>- approved for use in healthy* people, 2-49 y.o. who are not pregnant. </li></ul>
    62. 65. <ul><li>Each vaccine contains three influenza viruses: </li></ul><ul><ul><li>one A (H3N2) virus </li></ul></ul><ul><ul><li>one A (H1N1) virus </li></ul></ul><ul><ul><li>one B virus </li></ul></ul><ul><ul><li>2 weeks after vaccination - antibodies that provide protection against influenza virus infection develop in the body. </li></ul></ul>
    63. 66. Influenza A H1N1 Vaccine <ul><li>Not yet available </li></ul><ul><li>A European prototype of a swine flu vaccine has been achieved </li></ul><ul><li>Pandemic specific vaccines will not be available until 4-6 months after a pandemic virus has emerged </li></ul>
    64. 67. Pandemic influenza vaccine manufacturing process & timeline
    65. 68. When to Get Vaccinated <ul><li>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. </li></ul><ul><li>Timing & duration of influenza seasons vary.  </li></ul>
    66. 69. When H1N1 influenza is confirmed in a community (CDC recommends): <ul><li>Home isolation </li></ul><ul><li>School dismissal and childcare facility closure </li></ul><ul><li>Social distancing </li></ul>
    67. 70. Preventive measures for health care personnel <ul><li>single-patient room with the door kept closed </li></ul><ul><li>An airborne-infection isolation room with negative-pressure air handling. </li></ul><ul><li>Suctioning, bronchoscopy, or intubation should be performed in a procedure room with negative-pressure air handling. </li></ul><ul><li>Patients should wear a surgical mask when outside their room. </li></ul>
    68. 71. Preventive measures for health care personnel <ul><li>Frequently Hand washing & respiratory hygiene practices. </li></ul><ul><li>Routine cleaning and disinfection strategies </li></ul><ul><li>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. </li></ul>
    69. 72. Preventive measures for health care personnel <ul><li>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. </li></ul>
    70. 73. Preventive measures for health care personnel <ul><li>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. </li></ul>
    71. 74. Preventions for the Community: <ul><li>Cover the mouth & nose when coughing and sneezing. </li></ul><ul><li>Always wash hands with soap & water. </li></ul><ul><li>Use alcohol-based hand sanitizers. </li></ul><ul><li>Avoid close contact with sick people. </li></ul><ul><li>Increase body resistance. </li></ul>
    72. 75. Travel Advisory <ul><li>WHO is not recommending travel restrictions related to the outbreak of the influenza A(H1N1) virus </li></ul><ul><li>WHO do not believe entry and exit screenings would work to reduce the spread of this disease </li></ul><ul><li> May 15, 2009 - CDC Travel Health Warning for Novel H1N1 Flu in Mexico Removed </li></ul>
    73. 76. Department Of Health <ul><li>Oseltamivir (Tamiflu) </li></ul><ul><li>Designated referral centers 2 </li></ul><ul><ul><li>National Referral Center </li></ul></ul><ul><ul><ul><li>Research Institute of Tropical Medicine (RITM) </li></ul></ul></ul><ul><ul><li>Sub-national Referral Center </li></ul></ul><ul><ul><ul><li>Luzon & Metro Manila = San Lazaro Hospital </li></ul></ul></ul><ul><ul><ul><li>Visayas = Vicente Sotto Memorial Medical Center </li></ul></ul></ul><ul><ul><ul><li>Mindanao = Davao Medical Center </li></ul></ul></ul>1 Inquirer .net 2 DOH
    74. 77. DOH Lines of Defense <ul><li>Points of Exit and Entry Screening </li></ul><ul><li>Enhanced Diseases Surveillance </li></ul><ul><li>Preventive Measures </li></ul><ul><li>Prescribed Drug of Choice: Oseltamivir </li></ul><ul><li>Infection Control (N95 mask) </li></ul><ul><li>Social Distancing </li></ul><ul><li>Emergency powers: Martial Law </li></ul>DOH National Epidemiology Center
    75. 78. Thank You