What should be done for an adult with no significant past medical history who has been exposed to mouse droppings and is now experiencing congestion?

Management of Adult with Congestion After Mouse Droppings Exposure

Monitor closely for hantavirus pulmonary syndrome (HPS) symptoms over the next 45 days, as congestion following rodent exposure may represent early respiratory illness requiring urgent medical evaluation if fever, dyspnea, or systemic symptoms develop. 1

Immediate Assessment and Risk Stratification

The primary concern in this scenario is distinguishing between simple allergic rhinitis from mouse allergen exposure versus early hantavirus infection, which can present initially with non-specific upper respiratory symptoms before progressing to life-threatening pulmonary disease 2.

Key Clinical Features to Monitor

• Watch for progression to fever, cough, dyspnea, or systemic symptoms (fatigue, myalgias, chills) within 45 days of exposure, as these may indicate evolving HPS rather than simple allergic congestion 1, 2
• Seek immediate medical attention if any of the following develop: difficulty breathing, persistent fever, severe fatigue, or altered mental status 1
• Current isolated congestion may represent allergic response to mouse urinary proteins (Mus m 1), which causes respiratory symptoms in 32% of exposed individuals 3

Immediate Actions

Medical Evaluation Timing

• If only congestion is present without fever or systemic symptoms: Continue close self-monitoring for 45 days post-exposure 1
• If fever, dyspnea, or systemic symptoms develop: Seek immediate emergency evaluation, as HPS has high mortality and requires early supportive care 1
• Inform any treating physician about the rodent exposure history, as this is critical for appropriate diagnostic workup 1

Symptomatic Management for Isolated Congestion

• Standard antihistamines and decongestants are appropriate for allergic symptoms from mouse allergen exposure 3, 4
• Avoid further exposure to the contaminated environment until proper cleanup is completed 5

Environmental Remediation (Critical to Prevent Further Exposure)

The contaminated area must be properly cleaned to prevent ongoing allergen exposure and reduce infection risk. Never vacuum or sweep mouse droppings, as this aerosolizes infectious particles. 6, 1

Proper Cleanup Protocol

• Ventilate the area for at least 30 minutes before entering by opening doors and windows with cross-ventilation; remain outside during this period 6, 1
• Wear rubber, latex, vinyl, or nitrile gloves throughout the entire cleanup process 6, 5, 1
• Spray all droppings and contaminated surfaces with disinfectant or 1:10 bleach solution (1½ cups bleach per gallon water) until thoroughly soaked before touching anything 6, 1
• Use paper towels to pick up soaked droppings, place in plastic bag, then double-bag and dispose by burying 2-3 feet deep, burning, or placing in regularly emptied covered trash 6, 1
• Disinfect all potentially contaminated surfaces including floors, countertops, and any items that may have contacted rodent materials 6

For Heavy Infestations

• Wear additional protective equipment: coveralls, protective goggles, and appropriate respiratory protection (N-100 or P-100 respirator) 6, 1
• Contact local health department for guidance before cleanup in cases of heavy contamination 5, 1

Critical Pitfalls to Avoid

• Never dismiss respiratory symptoms following rodent exposure as "just allergies" without monitoring for progression—HPS can initially present with non-specific symptoms before rapid deterioration 2
• Never vacuum or sweep before disinfecting, as this creates infectious aerosols that dramatically increase hantavirus transmission risk 6, 1
• Never delay seeking emergency care if fever or dyspnea develops, as HPS requires immediate supportive care and has no specific antiviral treatment 1
• Do not use activated charcoal or other decontamination procedures if HPS is suspected, as these provide no benefit for viral infections and delay definitive care 1

Long-Term Monitoring

• Continue surveillance for 45 days post-exposure for any development of fever, respiratory symptoms, or unusual fatigue 1
• If symptoms remain limited to congestion without progression, this likely represents allergic response to mouse allergen (Mus m 1), which is present in 82% of US homes and causes respiratory symptoms in exposed individuals 3, 4
• Consider allergy evaluation if persistent congestion continues after environmental remediation, as mouse allergen sensitization can cause ongoing respiratory symptoms 3, 7