What are the treatment and isolation guidelines for influenza?

From the Guidelines

Treatment for influenza should be initiated as soon as possible with antiviral medications like oseltamivir (Tamiflu) or zanamivir (Relenza), especially for high-risk individuals, and isolation guidelines should be followed to prevent transmission. The most effective treatment is when started within 48 hours of symptom onset, with oseltamivir dosing varying by age and weight, as outlined in the American Academy of Pediatrics recommendations 1. For example, oseltamivir is recommended for children at high risk of complications, including those under 2 years old, and the dosage is based on weight, with 3 mg/kg per dose twice daily for term infants 0-8 months old.

Key considerations for treatment include:

• Starting antiviral treatment as soon as possible after illness onset, without waiting for confirmatory diagnostic test results 1
• Using clinical judgment to guide treatment decisions, considering factors like disease severity, time since symptom onset, and local influenza activity 1
• Providing supportive care, including rest, hydration, and fever management with acetaminophen or ibuprofen

Isolation guidelines to prevent transmission include:

• Staying home for at least 24 hours after fever resolves without fever-reducing medications
• Avoiding school or work until symptoms improve and fever resolves
• Using droplet precautions in healthcare settings, including wearing masks within 3-6 feet of the patient 1

It's essential to note that the virus can survive on surfaces for up to 48 hours and spreads primarily through respiratory droplets when infected people cough, sneeze, or talk. Therefore, following proper isolation and hygiene practices is crucial to prevent the spread of influenza. The Centers for Disease Control and Prevention (CDC) provides updated guidance on treatment and prevention, which should be consulted for the most current recommendations 1.

From the FDA Drug Label

Oseltamivir phosphate for oral suspension is indicated for the treatment of acute, uncomplicated illness due to influenza A and B infection in patients 2 weeks of age and older who have been symptomatic for no more than 48 hours. Initiate treatment with oseltamivir phosphate for oral suspension within 48 hours of influenza symptom onset. The recommended oral dosage of oseltamivir phosphate for oral suspension for treatment of influenza in adults and adolescents 13 years and older is 75 mg twice daily for 5 days. Oseltamivir phosphate for oral suspension is not a substitute for early influenza vaccination on an annual basis as recommended by the Centers for Disease Control and Prevention Advisory Committee on Immunization Practices.

The treatment guidelines for influenza using oseltamivir phosphate for oral suspension are to initiate treatment within 48 hours of symptom onset, with a recommended dosage of 75 mg twice daily for 5 days for adults and adolescents 13 years and older. Key points:

• Treatment should be initiated within 48 hours of symptom onset.
• The recommended dosage is 75 mg twice daily for 5 days.
• Oseltamivir phosphate for oral suspension is not a substitute for early influenza vaccination. 2

From the Research

Treatment Guidelines for Influenza

• The treatment of influenza may involve the use of anti-influenza drugs, such as oseltamivir and zanamivir, which can decrease the duration of illness by about 24 hours in otherwise healthy patients and may decrease the risk of serious complications 3, 4.
• These drugs are most effective when started within 48 hours of symptom onset, with the benefit being greatest when antiviral therapy is started within 24 hours of symptom onset 3.
• There are currently four approved anti-influenza drugs, and no single drug has been proven superior to the others 3.

Isolation Guidelines for Influenza

• Isolation of symptomatic infectious persons can reduce influenza transmission, but virus shedding that occurs without symptoms will be unaffected by such measures 5.
• Most individuals shed less than 10% of their total shed virus before symptom onset, and shedding after isolation varies substantially across individuals, isolation end points, and infectiousness assumptions 5.
• The effectiveness of isolation strategies for influenza requires understanding the interplay between individual virus shedding and symptom presentation 5.

Antiviral Therapy and Resistance

• The adamantane derivatives rimantadine and amantadine, and the neuraminidase inhibitors zanamivir and oseltamivir, are the only antiviral drugs currently approved for therapy and prophylaxis of influenza infections 6.
• Resistance to these drugs occurs due to mutations within the therapeutic target proteins M2 ion channel protein and viral neuraminidase, and only neuraminidase inhibitors are recommended for influenza treatment today 6.
• The M2 ion channel protein of A(H1N1)pdm09 viruses is associated with the Eurasian avian-like swine lineage and thus shows "natural" resistance to adamantane derivatives 6.