What precautions should we take to minimize the risk of transmitting Flu A to others at a family gathering while on Tamiflu (oseltamivir) and still within the contagious period?

Precautions for Attending Family Gathering with Flu A on Days 3-4 of Illness

I strongly recommend that you and your patient do not attend the Christmas Eve gathering, as you will both still be contagious and pose a significant transmission risk to family members, particularly those at high risk for severe complications. 1, 2

Understanding Your Contagious Period

• You remain infectious from 1 day before symptoms until approximately 5-7 days after symptom onset, meaning on days 3-4 you are still actively shedding virus 1, 2
• Infected persons are most infectious soon after developing symptoms, and while viral shedding decreases over time, you continue to excrete virus for up to 5 days (7 days in children) 3
• Tamiflu does not eliminate contagiousness—while oseltamivir reduces viral shedding quantity and duration, it does not make you non-infectious 4
• The absence of fever does not mean you are no longer contagious 2, 5

CDC Isolation Recommendations

• The CDC recommends staying home until at least 24 hours after fever resolves without fever-reducing medications, which typically means 5-7 days of isolation from symptom onset 2, 5
• Early voluntary home isolation of ill persons is a core personal protective measure recommended at all times during influenza season 2
• You should not return to normal activities based solely on feeling better—isolation must continue until you are fever-free for 24 hours without antipyretics AND symptoms are improving 5

Transmission Risks at Gatherings

• People in close proximity (within 1 meter/3 feet) to infected persons who are coughing and sneezing are at highest risk 3
• Influenza spreads through large droplets from coughing/sneezing and through direct/indirect contact (handshakes, contaminated surfaces) 3
• Aerosol transmission accounts for approximately half of all transmission events, meaning even careful distancing may not prevent spread 6
• Indoor family gatherings create ideal conditions for transmission due to prolonged close contact in enclosed spaces 6

If You Must Attend (Not Recommended)

Should you decide to attend despite the strong recommendation against it, implement these measures to reduce (but not eliminate) transmission risk:

Personal Protective Measures

• Wear a surgical mask at all times when within 3 feet of others to minimize droplet dispersal 3
• Practice meticulous hand hygiene—wash hands with soap and water or use alcohol-based hand sanitizer before and after any contact with people or surfaces 3, 5
• Cover all coughs and sneezes with tissues or your elbow, dispose of tissues immediately, and wash hands afterward 1, 5
• Avoid touching your eyes, nose, and mouth 7

Social Distancing

• Maintain at least 3 feet (ideally 6 feet) distance from all family members at all times 3
• Avoid any physical contact including handshakes, hugs, or kisses 3
• Do not share food, drinks, utensils, or dishes with anyone 7
• Stay in a separate area from the main gathering as much as possible 3

Protecting High-Risk Family Members

• Identify and completely avoid contact with anyone who is:
  • Age 65 years or older 1
  • Children under 2 years 1
  • Pregnant 1
  • Has chronic lung disease, heart disease, kidney disease, liver disease, diabetes, or weakened immune system 1
• These individuals should ideally not attend if you are present, as they are at very high risk for severe complications and hospitalization 1

Environmental Measures

• Ensure excellent ventilation—open windows if weather permits 6
• Avoid touching shared surfaces; if you must, sanitize your hands immediately afterward 3
• Do not help with food preparation or serving 3

Critical Caveats

• These measures reduce but do not eliminate transmission risk—even with perfect adherence, you can still infect others 8, 6
• Mask wearing by ill persons has some evidence for protecting others, but is not foolproof, especially during eating and drinking when masks must be removed 8
• Contact reduction measures during institutional outbreaks are recommended specifically to limit transmission between treated and untreated persons, highlighting that antivirals alone are insufficient 3
• The safest option for your family's health, particularly vulnerable members, is to postpone your attendance until you meet CDC criteria for ending isolation 2, 5

Alternative Recommendation

Consider virtual participation via video call to maintain family connection while protecting everyone's health. This eliminates all transmission risk while allowing you to be part of the celebration. 1, 2