Influenza (also known as flu) is a contagious respiratory illness caused by flu viruses. People who have influenza like illness (ILI) may present with following symptoms. Cardinal symptoms of Influenza like illness ILI - an acute respiratory infection (sudden cough and sore throat) with measured fever of ≥100.4 F: with onset within the last 10 days Other associated symptoms Muscle or body aches Headaches Fatigue Vomiting and diarrhea (more common in children than adults) Running or stuffy nose All individuals seeking consultations for flu-like symptoms should be screened at healthcare facilities, both Government and private or examined by a doctor and categorized into A, B and C. In order to prevent and contain outbreaks of Influenza, the following guidelines for screening, testing and isolation are to be followed: Category- A (uncomplicated/mild) Symptomatology: Patients with mild fever and cough/ sore throat with or without body aches, headache, diarrhea and vomiting will be categorized as Category-A: Diagnostic test: Testing of such patients (Category-A) for Influenza is not required Treatment: They do not require Oseltamivir and should be treated for the symptoms mentioned above. The patients should be monitored for their progress and reassessed at 24 to 48 hours by the doctor Isolation: Patients should confine themselves at home and avoid mixing up with public and high-risk members in the family Category-B (uncomplicated but severe symptoms /high risk groups) In addition to all the signs and symptoms mentioned under Category-A, if the patient has high grade fever (≥ 102 F) and severe sore throat In addition to all the signs and symptoms mentioned under Category-A, individuals having one or more of the following high risk conditions: Age ≥65 years Pregnant (including up to two weeks post-partum) Infants and Children aged ≤ 5 years (especially <2 years of age) Chronic respiratory disease Chronic heart, kidney, liver or neurological disease Diabetes mellitus Blood disorders (including haemoglobinopathies) Persons with immunosuppression (including HIV/ AIDS & use of longterm (≥ 2 weeks) corticosteroids, Post-transplant patients) Extreme obesity (BMI ≥ 40 kg/m2 ) Malignancy Diagnostic test: Testing of the Category-B patient for Influenza is not required Treatment: They should receive Oseltamivir along with symptomatic treatment. Isolation: All patients of Category-B should confine themselves at home and avoid mixing with public and high-risk members in the family. Category-C (Complicated): Symptomatology: In addition to the above signs and symptoms of Category-A and Category-B, if the patient has one or more of the following: Symptoms and signs of complicated influenza SymptomsSigns Breathlessness Tachypnoea Hemoptysis SpO2<90% Altered mental status Hypotension Somnolence and Poor feeding (in children) Reduced urine output Seizures Cyanosis Decreased urine output Persistence or worsening of initial symptoms beyond 72 hours Worsening of underlying chronic conditions like Diabetes Mellitus, Chronic Kidney Disease etc. Diagnostic test: These patients should be tested for influenza; start empirical antiviral therapy (oseltamivir) while results are pending Treatment: immediate hospitalization and treatment Source : Ministry of Health and Family Welfare Guidelines