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Most King County offices will be closed on Monday, for Indigenous Peoples' Day.  
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STAYING OPEN: The Sexual Health Clinic will be open on Indigenous People's Day on October 10, 2022 during normal hours from 7:30 am to 6:00 pm. The Monkeypox Clinic will be open 8:00 am to 3:00 pm. The MAX Clinic will be closed like most King County offices on that day.

The Sexual Health Clinic (SHC) provides both appointments and walk-ins. Services are available Mon, Wed, Thurs and Friday at 7:30 am - 6:00 pm and Tuesdays at 9:30 am - 6:00 pm.


If you want to be vaccinated for monkeypox at the Sexual Health Clinic, please note that the hours are 8:00 am – 3:00 pm Monday, Wednesday, Thursday, Friday and 9:30 am – 3:00 pm on Tuesday, if we have vaccines available.

  • To check on vaccine availability and eligibility, call the Public Information Call Center (the PICC line) at 206-477-3977.
  • Do not call the PICC line to ask about wait times at the Sexual Health Clinic as they vary from hour to hour and day to day. Wait times for the SHC can be long for assessment of exposure and possible infection for testing and treatment, however vaccine line wait times vary.

Monkeypox vaccine is administered in two doses spaced at least four weeks apart. Learn about second doses on the monkeypox vaccine webpage.


If have STI symptoms or have been exposed to HIV or an STI:
Please call 206-744-3590 to schedule an appointment.
You may also walk-in for services. Please arrive no later than 4:00 pm. Clinic hours begin at 7:30 am on Mon, Wed, Thurs, and Fri, and 9:30 am on Tuesdays. We do our best to see every patient, but walk-in patients may experience a wait.


If you don't have any symptoms and you would like to walk-in for HIV/STI screening:
Please arrive no later than 4:00 pm. Clinic hours begin at 7:30 am on Mon, Wed, Thurs, and Fri, and 9:30 am on Tuesdays. We do our best to see every patient, but walk-in patients may experience a wait.

Walk-in clinic hours

Ninth and Jefferson Building
908 Jefferson St, 11th Floor
Seattle, WA
Phone: 206-744-3590

  • Monday, 7:30 am to 6:00 pm
  • Tuesday, 9:30 am - 6:00 pm
  • Wednesday, 7:30 am - 6:00 pm
  • Thursday, 7:30 am to 6:00 pm
  • Friday, 7:30 am to 6:00 pm
  • Sat/Sun, closed

No appointment needed. We are a walk-in clinic. Interpreters are available.

You will be seen regardless of your ability to pay. Payment for medical services is based on a sliding fee scale. Non-judgmental!

All are welcome!

Professional. Comprehensive. Confidential. Affordable.


We can help

If you think you might have symptoms of a sexually transmitted disease (STD), get tested and treated right away. Even if you do not have symptoms, you could have an STD. Come see us and get an STD checkup...and peace of mind.

Get tested and treated.
We provide confidential testing and treatment, and we can answer your questions about HIV and other STDs.

Get evaluated for PrEP.
Pre-Exposure Prophylaxis (PrEP) is a pill that can prevent HIV infection. It's for HIV negative people who are at risk of becoming HIV positive through sexual activity or injecting drugs.

Get help finding HIV care.
All people living with HIV in Washington State can get HIV medical care. We can connect you to the right medical provider.

Learn where else you can be tested.
Select Public Health Centers and community-based organizations that provide HIV and STD testing.

Quotes from our patients

I like that I can get tested and treated in one stop."

Everyone is professional and it seems community driven. I have recommended the clinic to my friends."

I was nervous when I first came in but almost immediately after sitting with the staff all my anxiety went away because they were so easy to talk to."

This office is a safe space for all people including lesbian, gay, bisexual, pansexual, asexual, straight, two-spirit, transgender, cisgender, queer, questioning, ally.

About us

Learn about the dedicated staff of the Sexual Health Clinic at Harborview Medical Center.

Dwyn Dithmer, Nurse Practitioner

Dwyn Dithmer, MS, ARNP, is a Board Certified Family Nurse Practitioner. Over the course of her 30 year career, she has worked in the clinic diagnosing and treating sexually transmitted infections. Additionally she recruits and enrolls participants in various STI related studies. She has Masters degrees from both Binghamton University (NY) and Pace University. Her Bachelor's degree is from Georgetown University.

Colleen Duncan, Registered Nurse

Colleen Duncan, RN, graduated from Thomas Jefferson University in 2019 with a Bachelor's in Nursing. She started her career working at a hospital, then switched to a federally funded community health clinic and fell in love with public health/community health. She joined the sexual health clinic in 2022 to focus on sexual and reproductive health, in which she is pursuing further education. She is passionate about creating a safe and nonjudgmental healthcare experience for patients and about increasing healthcare opportunities for those who have less access to healthcare.

Susannah Hermann, Nurse Practitioner

Susannah Herrmann graduated from the University of Washington Family Nurse Practitioner program in 2001. After a brief stint in family practice she worked in women's reproductive health for 10 years. Susannah joined the Sexual Health Clinic in 2006. She strives to create a safe space in which all patients feel welcome getting tested, treated, and discussing strategies for reducing risk. She is bilingual in English and Spanish.

Fred Matías, Registered Nurse

Fred Matías, BSN, RN, is a registered nurse who joined the Sexual Health Clinic in November 2018. He graduated in 2014 with his BSN from the University of Alabama in Huntsville. He has worked as a clinic nurse at an HIV clinic and at a TB clinic. He speaks English, Spanish, and Portuguese.

Erin Morton, Nurse Practitioner

Erin Morton, ARNP, is a Nurse Practitioner with the Sexual Health Clinic since 2021. Erin received her Master of Science in Nursing from the University of Pennsylvania in 2016. Since then, she has worked in the fields of sexual and reproductive healthcare, transgender care, and gynecologic oncology. She is passionate about health equity, and creating an environment where patients feel safe, heard, and empowered to be active partners in their healthcare.

Eduardo Munoz, Physician Assistant

Eduardo Munoz is a Physician Assistant who has worked at the Sexual Health Clinic since August 1, 1990.

Negusse Ocbamichael, PA-C, graduated from the University of Washington Medical School, PA program. His clinical experience and interests are in infectious diseases, reproductive and sexual health. For over 28 years, he has worked at the King County Sexual Health Clinic, University of Washington, Virology Research Clinic, HIV Prevention Trials Network and International medicine clinic at Harborview medical center, as a clinician, researcher and administrator. He also served as a Faculty member, speaker and advisory committee member for Seattle STD/HIV prevention and training center.

Rafael Padilla, Registered Nurse

Rafael Padilla graduated in 2018 from the University of Washington in Seattle with a Bachelor's in Nursing. He first completed a nurse residency program at a family health clinic where he focused primarily on the management and care of chronic wounds. Rafael joined the Sexual Health Clinic in 2020 to pursue his interests in sexual health and to work more closely with LGBTQ+ communities.

Laura Rishel, Nurse Practitioner

Laura Rishel, MSN, ARNP, is a nurse practitioner at the Sexual Health Clinic at Harborview. Prior to coming to Harborview in January 2018, she worked in primary care at community health clinics in Bellingham and in Maine, where she most enjoyed working in preventive care, sexual and gynecologic health, transgender care and homeless access to health. Her clinical interests include sexual health, transgender care, women's health, and contraception. Laura earned her Master's in Nursing in 2012 from Yale University School of Nursing, and her Bachelor's degrees at the University of Washington.

Thepthara "Nui" Pholsena, Nurse Practitioner

Thepthara "Nui" Pholsena graduated from University of Washington with a Master of Nursing in 2011. Her clinical experience and interests are in chronic diseases, both infectious and non-infectious. For the last three years, she has worked at UW Virology Research Clinic as a research clinician focusing on herpes and vaccine research. She enjoys patient teaching and counseling.

Shannon Winters, Nurse Practitioner

Shannon Winters is a board-certified Adult Nurse Practitioner, credentialed through the American Nurses Credentialing Center, and joined the team at the Sexual Health Clinic in May 2020. After graduating with bachelor's and master's degrees in nursing from the University of Washington in 2009, she spent the first 9 years of her career working in federally-funded family planning clinics in Wyoming and Northern Colorado. During her time in family planning, she enjoyed providing contraceptive care, diagnosing and treating STIs, providing routine gynecologic care, and providing care to patients of all genders.


Link/share our site at www.kingcounty.gov/sexualhealth