Infectious Diseases

Image show personal protective measures such as mask, hand sanitizer and medications used during Public Health Emergencies.

Preparing for infectious diseases helps protect your household, workplace, and community. For respiratory illnesses such as flu, COVID-19, and respiratory syncytial virus (RSV), combine vaccination, cleaner air, good hygiene, and staying home when sick.

How infections spread

Respiratory viruses can spread through shared air. People release infectious particles when breathing, talking, coughing, or sneezing. Others can breathe in these particles, especially in crowded indoor spaces with poor ventilation.

Depending on the infection, germs can also spread through direct contact, contaminated hands or surfaces, or unsafe food and water. Prevention measures should match the disease. Follow current public health guidance during an outbreak.

Make cleaner air part of everyday prevention

Cleaner air is a core CDC prevention strategy. Ventilation brings in outdoor air, while filtration removes particles from indoor air. Both help reduce exposure to respiratory viruses.

  • Open windows and doors when outdoor air quality, weather, and safety allow.
  • Use exhaust fans that vent outdoors to help move indoor air out.
  • Use a portable high-efficiency particulate air (HEPA) cleaner appropriate for the room.
  • Maintain heating, ventilation, and air conditioning filters according to the manufacturer’s instructions. When visitors are present, consider setting the system’s fan to “on” instead of “auto.”
  • Move gatherings and activities outdoors when conditions allow.

Read CDC guidance on cleaner air at home and in shared spaces.

Stay up to date on vaccinations

Ask your healthcare provider or pharmacist which vaccines are recommended for your age, health conditions, and circumstances. Vaccination helps protect against serious illness.

Stay home when sick

If you have respiratory symptoms that are not explained by another cause, stay home and away from others, including household members who are not sick.

Under CDC’s general respiratory-virus guidance, you can return to normal activities when both conditions have been true for at least 24 hours:

  • Your symptoms are improving overall.
  • You have no fever without using fever-reducing medication.

For the next five days, take added precautions around others: improve air quality, wear a well-fitting mask, keep distance, and consider testing. This is especially important around people at higher risk of serious illness.

If a fever returns or you feel worse, stay home again. Healthcare settings and certain infections have separate guidance.

Check CDC’s current guidance on staying home and returning to activities.

Practice good hygiene

  • Wash your hands regularly with soap and water.
  • When soap and water are unavailable, use hand sanitizer containing at least 60% alcohol.
  • Cover coughs and sneezes with a tissue or your elbow. Dispose of used tissues and clean your hands.
  • Clean frequently touched surfaces regularly with an appropriate household cleaner. Follow product instructions.

Handwashing and surface cleaning work alongside cleaner air and other prevention measures.

Read CDC guidance on hygiene and respiratory-virus prevention.

Plan ahead for your household and workplace

  • Keep healthcare provider and pharmacy contact information accessible.
  • Plan medication refills and keep essential supplies, such as soap, tissues, masks, and a thermometer, available.
  • Arrange help with food, caregiving, or other essentials if someone needs to stay home.
  • Discuss sick leave, remote work, and school absence arrangements before illness occurs.
  • For shared buildings, assign someone to check ventilation and maintain air filters.
  • Ask household members at higher risk of serious illness to discuss testing and treatment plans with their healthcare provider.

Know when to get help

Call 911 for emergency symptoms such as trouble breathing or persistent chest pain. Contact your healthcare provider about concerning symptoms, especially if you are at higher risk of serious illness.

Follow current health guidance

Recommendations may change as new information becomes available. Check publication dates and follow disease-specific instructions from public health officials.

Together we are MenloPrepared.

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