Novel Influnza A H1N1 Virus Infection This information is brought to you as public service from:
Shreya Life Sciences Pvt. Ltd
Swine Flu Background • Contagious respiratory disease with mild to severe symptoms. • Human to human transmission like seasonal influenza via sneezing coughing, etc. • The first outbreak in 1918 called “Spanish influenza pandemic affecting 1/3 of world population (500 million) with 50 million deaths.
Swine Flu Background • Second outbreak in 1976 in New Jersey • Vaccination halted after 40 million vaccination due to appearance of GuillainBarre Syndrome and 25 deaths. • Increased flu risk in pregnant women, particularly during the second and third trimesters. • Increased risk of fetal death or spontaneous abortions in infected pregnant women.
Novel H1N1 flu infection • From April 15, 2009 to July 24, 2009, it is estimated that more than one million people became ill with novel H1N1 flu in the USA. • From April 15, 2009 to July 24, 2009, a total of 43,771 confirmed and probable cases of novel influenza A (H1N1) infection were reported. • Of these cases reported, 5,011 people were hospitalized and 302 people died. • In India 782 cases reported - 511 cured - 4 deaths.
Novel H1N1 flu Global Map
Confirmed death and infections Confirmed infections Unconfirmed infections
Swine Flu Features • Duration 4 – 6 days. • Infectious period – 1 day prior to onset of symptoms to 7 days after onset. • Suspect in pt who present with febrile respiratory illness • Onset within 7 days of close contact with confirmed infection. • Onset within 7 days of travel to areas where sustained human transmission exists • Acute illness in person who resides in community where atleast 1 confirmed case.
Symptoms & Complications • Symptoms of swine flu are similar to influenza infections. • Strong immune response may cause some collateral tissue damage. • Majority (about 90%-95%) of people feel terrible but recover with no problems.
Symptoms & Complications • Some patients develop severe respiratory symptoms and need respiratory support. • Patients may get pneumonia (bacterial secondary infection) if the viral infection persists, and some develop seizure. •
Death often occurs from secondary bacterial infection of the lungs; appropriate antibiotics need to be used in these patients.
• Mortality Rate – 1% - 6%
Novel Influenza A H1N1 virus • Novel H1N1 virus is also called “swine flu” because many of the genes in this new virus were very similar to influenza viruses that normally occur in pigs (swine). • It has two genes from flu viruses that normally circulate in pigs, bird (avian) genes and human genes. • Scientists call this a "quadruple reassortant" virus.
Symptoms in hospitalized novel H1N1 flu patients Symptom
Number (%)
Fever*
249 (93%)
Cough
223 (83%)
Shortness of breath
145 (54%)
Fatigue/Weakness
108 (40%)
Chills
99 (37%)
Myalgias
96 (36%)
Rhinorrhea
96 (36%)
Sore Throat
84 (31%)
Headache
83 (31%)
Vomiting
78 (29%)
Wheezing
64 (24%)
Diarrhea
64 (24%)
Signs of Emergency • Novel H1N1 swine flu can progress rapidly. • Shortness of breath, either during physical activity or while resting, difficulty in breathing, turning blue, bloody or colored (not clear) sputum, chest pain. • Altered mental status. • High fever that persists beyond three days. • Low blood pressure. • In children, danger signs include fast or difficult breathing,.
Emergency in Children • In children, emergency warning signs are: – Fast breathing or trouble breathing – Bluish or gray skin color – Not drinking enough fluids – Severe or persistent vomiting – Not waking up or difficulty in waking up, not interacting , lack of alertness, little or no desire to play. – Being so irritable that the child does not want to be held – Flu-like symptoms improve but then return with fever and worse cough
Emergency in Adults • In adults, emergency warning signs are: • Difficulty breathing or shortness of breath • Pain or pressure in the chest or abdomen • Sudden dizziness • Confusion • Severe or persistent vomiting • Flu-like symptoms improve but then return with fever and worse cough
Care for Swine Flu • Sick patient • Bed rest, increased fluid consumption, cough supressants, analgesic antipyretics, avoid close contact, wash hands after contact, avoid touching eyes, nose and mouth. • Self isolate in home for 7 days or more if flu like symptom. • Wear face mask, if going out. • Seek medical help if breathing difficulty or severe illness.
Care for Swine Flu • Household not sick • Remain at home at the earliest signs of sicknes. • Minimize contact with community • Designate single family member as care taker. • Wash hands with soap and water frequently. • Do not use utensils and linen used by patient, without washing.
Novel H1N1 flu infection • Estimated community rate of influenza-likeillness approximately 6% - 6.9% of the population.
• Causes greater disease burden on people younger than 25 years of age than older people .
Novel H1N1 flu infection • Greater risk of serious flu-related complications in pts of asthma, diabetes, heart disease, kidney disease, suppressed immune system, neurocognitive, neuromuscular disorder, obesity, age group <5 and >65 yr and pregnancy.
Novel H1N1 flu infection • The generation time – acute respiratory illness (ARI) - 2.0-3.1 days – influenza like illness (ILI) - 2.4-3.1 days • A secondary attack rate in household contacts – For acute-respiratory-illness (ARI) -18 % to 19% – For influenza-like-illness (ILI) - 8% to 12%.
Preventive Care • People infected with novel H1N1 flu shed virus may be able to infect others from 1 day before getting sick to 5 to 7 days after. – Cover nose and mouth with a tissue when you cough or sneeze. – Wash hands often with soap and water, especially after you cough or sneeze.
Preventive Care – Avoid touching eyes, nose or mouth. – Try to avoid close contact with sick people. – If sick with flu-like illness, stay home for at least 24 hours after your fever is gone. – Healthy person with an ill family member at home can go to work as usual with daily health monitoring and precautions.
Novel H1N1 flu infection Case Rate Hospitalization Rate
Mortality in 268 Hospitalized Patients
Contamination & Cleaning • Virus can survive on surfaces and can infect a person for 2 to 8 hours after being deposited on the surface. • Virus is destroyed by heat (167-212°F [75100°C, chlorine, hydrogen peroxide, detergents (soap), iodophors (iodine-based antiseptics), and alcohols. • Virus spread when a person touches something that is contaminated and then touches his or her eyes, nose, or mouth.
Contamination & Cleaning • Novel H1N1 viruses are not spread by food. • Tap water that has been treated by conventional disinfection processes does not spread the virus. • Chlorine treated water in swimming pool water parks does not spread the virus but recreational water venues can.
Contamination & Cleaning • To prevent the spread of influenza virus • keep surfaces (especially bedside tables, surfaces in the bathroom, kitchen counters and toys for children) clean with a household disinfectant. • Linens, eating utensils, and dishes should not be shared without washing thoroughly with soap and water first. • Wear face mask when moving in public places
Recommended Treatment & Prophylaxis • Treatment • Same as those recommended for seasonal influenza • Oseltamivir, zanamivir ( amantadine, rimantadine) for 5 days. • Start drug treatment within 48 hours of onset of symptoms.
Recommended Treatment & Prophylaxis • Chemoprophylaxis •
Oseltamivir, zanamivir for 7 days after the last known exposure to an ill confirmed case.
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Household close contacts who are at high-risk for complications.
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School children who had close contact (face-toface) with a confirmed or suspected case.
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Travel to infection areas if at high-risk for complications.
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Health care workers or public health workers who had unprotected close contact with an ill confirmed case.
Preventive Measures In School • Stay home when sick for at least7 days or for 24 hours after no fever, or signs of fever. • Students who have an ill household member should stay home for five days from the day the first household member got sick. • Separate ill students and staff and wear face mask. • Cover nose and mouth when coughing or sneezing.
Preventive Measures In School • Wash hands frequently with soap and water. • Frequent cleaning of areas that students and staff touch in routine manner. • Check students and staff for fever and other symptoms of flu daily. • Early treatment of high-risk students and staff. • Consideration of selective school closure.
All the best……