Summary
We first reported an increase in pertussis cases in May. Pertussis (whooping cough) cases have continued to increase in Pierce County and across Washington. Healthcare providers should:
- Be aware of a significant increase in pertussis activity in Pierce County and most areas of Washington.
- Assure children and adults are up to date on pertussis vaccination (see CDC guidelines).
- Pregnant people at 27–36 weeks gestation (third trimester) should receive 1 dose of Tdap vaccine (tetanus, diphtheria, pertussis) during each pregnancy.
- Consider pertussis when evaluating people with a cough illness.
- Test patients who may have pertussis and treat patients strongly suspected of having pertussis.
Epidemiologic picture
1,193 cases of pertussis have been reported this year, compared to 51 cases during the same period in 2023 (a 23-fold increase). Centers for Disease Control and Prevention (CDC) estimates only 10% of pertussis infections are identified and reported.
Consider pertussis when you see:
- Respiratory illness in infants under 1 year old, especially when paired with difficulty feeding or apnea.
- Cough illness, in patients of any age, paired with any of these:
- Paroxysmal cough.
- Gagging, post-tussive emesis, or inspiratory whoop.
- Cough lasts 2 weeks or longer.
- Apnea.
- Respiratory illness of any duration in patients who came into direct contact with someone with known or suspected pertussis. Pertussis symptoms can be non-specific during the early (catarrhal) stage of illness, and might not include cough.
- The incubation period for pertussis is 5–21 days.
If you suspect pertussis:
- Test: Collect a nasopharyngeal (NP) swab for Bordetella pertussis PCR or culture. You should not use serology to diagnose pertussis.
- Treat: Follow CDC’s treatment guidance.
- Exclude: Tell the patient to stay home from work, school, or childcare until after they have completed 5 full days of appropriate antibiotics.
- Prophylaxis: Consider preventive antibiotics for the entire household if a member meets any “high risk” criteria. Those at high risk for pertussis include:
- Infants under 1 year old (highest risk for severe disease and death).
- Pregnant people at 27–36 weeks gestation (third trimester).
- Healthcare workers who come into direct contact with patients.
- People who come into direct contact with infants under 1 year old or pregnant people. That includes childbirth educators, childcare workers, or members of a household with an infant.
- Report: Contact the Health Department within 24 hours for investigation. Call us at (253) 649-1412 or fax a report to (253) 649-1389.
Pertussis vaccination coverage in Washington
Pertussis vaccination coverage has declined among children aged 19-35 months in Washington State, from 72% in 2019 to 65% in 2023. High vaccination coverage is the best way to limit community transmission.
Tdap vaccination uptake among pregnant people has also declined slightly, from 86% in 2019 to 82% in 2022. Tdap vaccination during the third trimester helps protect infants, who are at highest risk of severe illness and death.
A strong provider recommendation is crucial for vaccine acceptance in all age groups.
Resources
- Weekly pertussis update, DOH.
- Pertussis clinical features, CDC.
- Collecting a nasopharyngeal swab clinical specimen video, CDC.
- Best practices for using PCR to diagnose pertussis, CDC.
- Pertussis treatment, CDC.
- Immunization schedules, CDC Advisory Committee on Immunization Practices (ACIP).
- Vaccines are available from most pharmacies and healthcare providers. Find vaccine events and more information for children and adults.
- Ask the experts about pertussis, immunize.org.
- Report notifiable conditions, Tacoma-Pierce County Health Department.