If a relative has adenovirus, how likely am I to contract it?

Risk of Contracting Adenovirus from an Infected Relative

If a relative has adenovirus, your risk of contracting it is very high—adenovirus is extremely contagious, with transmission occurring readily through respiratory droplets, direct contact, and contaminated surfaces where the virus can survive for up to 28 days. 1

Transmission Dynamics and Contagiousness

Adenovirus is one of the most transmissible viral infections you can encounter in household settings. The virus spreads through multiple routes simultaneously, making prevention challenging:

• Respiratory transmission occurs through coughing, sneezing, and close conversation, similar to common cold viruses 2, 3
• Direct contact transmission happens through touching infected individuals or sharing personal items like towels, pillows, and utensils 1
• Fomite transmission is particularly concerning because adenovirus remains infectious on surfaces in a desiccated state for up to 28 days—far longer than most respiratory viruses 1

Infectious Period

Your relative remains contagious for 10-14 days from symptom onset (or from onset in the second eye if conjunctivitis develops), though some sources consider 7 days as the minimum contagious period 1, 4. During this entire period, viral shedding occurs and transmission risk remains high.

Risk Factors That Increase Your Susceptibility

Your personal risk is higher if you:

• Are a young child (adenovirus infections are most common in children due to lack of prior immunity) 2, 3
• Are immunocompromised (organ transplant recipients, HIV-positive individuals, or those on immunosuppressive therapy face higher risk of severe disease) 5, 6
• Live in close quarters with the infected relative (shared bathrooms, bedrooms, or common areas increase exposure) 2, 3
• Work in healthcare or childcare settings where you could subsequently transmit to vulnerable populations 1

Critical Prevention Measures

To minimize your risk of infection, implement these evidence-based strategies immediately:

• Hand hygiene with soap and water is essential—alcohol-based sanitizers alone are insufficient against adenovirus 1
• Separate personal items including towels, pillows, bedding, and eating utensils 1
• Avoid close contact with the infected relative, particularly avoiding face-to-face interaction within 6 feet 1
• Disinfect surfaces daily using dilute bleach solution (1:10 household bleach to water ratio), as this is the only reliably effective disinfectant against adenovirus—70% isopropyl alcohol wipes are NOT adequate 1
• Discard any shared eye drops or cosmetics if conjunctivitis is present, as these can harbor infectious virus 1

Expected Clinical Course If You Contract It

If you do become infected, expect:

• Upper respiratory symptoms (fever, sore throat, cough, congestion) lasting 7-10 days in most immunocompetent individuals 4, 2
• Conjunctivitis may develop, characterized by red eyes, watery discharge, and light sensitivity 4
• Gastrointestinal symptoms (diarrhea, nausea) occur in approximately 15-20% of cases, particularly with certain serotypes 7
• Self-limited illness in healthy individuals, though symptoms can be uncomfortable 2, 3

When to Seek Medical Attention

Seek immediate medical evaluation if you develop:

• Severe respiratory distress or difficulty breathing 2, 3
• High fever persisting beyond 3-5 days 2
• Severe eye pain or vision changes (suggesting corneal involvement) 1
• Signs of dehydration from persistent diarrhea 7

The bottom line: Assume you will be exposed and implement rigorous infection control measures immediately. The combination of prolonged surface survival, multiple transmission routes, and extended infectious period makes household transmission of adenovirus extremely difficult to prevent entirely, but meticulous hygiene can reduce your risk substantially.