Viral Update: Illness and Volume Trends and Helpful Resources for Our Community

Our goal is to share information and resources with our larger community as we all work together to care for patients facing viral illnesses.

Viral Trends and Hospital Volumes

• ED Volumes: ED volumes continue to be strong, with expectations to continue through mid-May.
• Influenza: Influenza activity is likely just past peak, though influenza B remains elevated and is expected to persist for the next 2 to 4 weeks. A post–spring break increase in influenza B was observed, particularly in school-aged children.
• RSV: Respiratory syncytial virus (RSV) activity is past peak and steadily declining locally, though still present at moderate levels nationally.
• Measles: The 2026 U.S. confirmed case count is 1,967. After a busy start to the year, new cases are slowing nationally. Secondary cases from our two most recent local cases may present between April 10 and April 29. If referring a patient to Seattle Children’s for measles assessment and testing, a plan must be in place prior to arrival. Please call Mission Control at 206-987-8899 in advance. Mission Control is provider-to-provider only; families should not call. If you need a resource for measles postexposure prophylaxis (PEP), please contact your local health department.
• SARS-CoV-2 and Seasonal Coronaviruses: SARS-CoV-2 activity remains low based on wastewater and ED data. Seasonal coronaviruses (229E, NL63, OC43, HKU1) have declined from recent peak levels and are now at moderate activity.
• Mpox: Mpox testing is available at Seattle Children’s. If you feel your patient may have mpox and want them tested, please call Mission Control at 206-987-8899.
• Other Respiratory Viruses: Rhino/enterovirus remains the most common noninfluenza, non-RSV pathogen detected. Seasonal human metapneumovirus (HMPV) and parainfluenza activity remain low.
• Mycoplasma: Mycoplasma activity remains low, with a 2% positivity rate last week.
• Pertussis: Activity is down after two years of increased positivity at both the state and national level. The national count this year is lower than at the same time last year. Locally, we continue to see zero to two positives per week. Continue to encourage vaccination.
• Norovirus and Rotavirus: Norovirus and rotavirus activity remains high.

Special Pathogens Team Update

Seattle Children’s has a special pathogens team that is continuously monitoring worldwide outbreaks to keep our staff, patients and community providers informed.

A suspected outbreak of viral hemorrhagic fever is being investigated in South Sudan. Pakistan, Senegal and Iraq have reported cases of Crimean-Congo hemorrhagic fever this year.

There are current outbreaks of Nipah virus in both India and Bangladesh. It is typically seen seasonally in India, but there have been reports of increased mortality with the current outbreak.

A little information about Nipah virus:

• The virus: Nipah is a paramyxovirus that causes severe encephalitis and pneumonia.
• Incubation period: Typically 4 to 14 days.
• The illness: Sometimes classified with viral hemorrhagic fevers due to its severe, systemic nature and potential for hemorrhage.
• Transmission: Spread via fruit bats, pigs or human-to-human contact.
• Fatality rate: Estimated between 40% and 75%.
• Symptoms: Fever, headaches, vomiting, sore throat and rapidly progressing encephalitis.

If you are treating a patient with recent (within the last month) travel to areas affected by hemorrhagic fevers and suspect a related illness, please contact your local public health department immediately.

If you are referring an ill patient who needs urgent evaluation to Seattle Children’s, please call Mission Control at 206-987-8899 before sending the patient.

Measles Resources

• Webinar Recording: Measles Community Response
• Measles One-Pager for Healthcare Providers (AAP)
• Measles - For Healthcare Professionals (CDC)
• Measles Specimen Collection Instructions for RT-PCR (DOH)
• Measles Specimen Collection Instructions for Serology (DOH)
• Immunization Schedules (CDC)
• Safety Information for Measles, Mumps, Rubella (MMR) Vaccines (CDC)
• Recognizing Measles in Your Patients (Pediatric Pandemic Network)
• Vitamin A and Measles Vaccine Talking Point (Pediatric Pandemic Network)
• Measles FAQ for Families & Caregivers (Pediatric Pandemic Network)

How You Can Help

• To help maintain ED volumes, consider reminding families of your clinic’s resources and procedures for urgent and after-hours patient needs to help direct them to the most appropriate site of care.
• Encourage families to review our ED vs. Urgent Care guide to find the most appropriate care setting. We have options for in-person and virtual urgent care, orthopedic urgent care and psychiatric urgent care.
• Families should be prepared that if viral testing is deemed clinically appropriate, it will typically be performed using a panel that identifies only influenza, RSV and COVID-19.
• Before sending your patient to the ED, contact our Mission Control team with as much notice as possible at 206-987-8899. This helps us plan for your patient’s arrival, especially if there are concerns for communicable diseases.

Additional Resources

• View the respiratory virus data dashboard for the latest Seattle/King County trends for COVID-, RSV- and influenza-related ED visits.
• Read the situational summary on H5 bird flu to stay updated on the current highly pathogenic avian influenza A (H5N1) outbreak.
• View these resources on vaccine guidance for the most current COVID vaccination recommendations.
• Review the latest viral activity on the National Respiratory and Enteric Virus Surveillance System dashboard.