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COVID-19 Vaccination

The healthcare providers at Greenhouse Internists encourage their patients to receive the COVID-19 vaccine when it becomes available to them.  We believe the vaccine is safe and effective.  To learn more about the vaccine, CLICK HERE.

The vaccine is being offered in phases, with high risk individuals prioritized.  We encourage you to be patient as we move through these phases and understand that eligibility might vary, depending where you live or work.  Currently, Greenhouse is not offering the vaccine.  Larger health systems and pharmacies that have the space to meet the storage requirements of the vaccine and monitor patients after the vaccine is administered will be offering the vaccine.

TO REGISTER FOR THE VACCINE, see the following sites:

♦  If you live anywhere in PA:
PA Department of Health

♦  If you have been a patient at Chestnut Hill Hospital (currently registering patients over age 75):
Tower Health

♦  If you live in Philadelphia:
Black Doctors Consortium
Philly Fighting COVID

♦  If you live in Montgomery County:
Montgomery County Office of Public Health


Since the beginning of the COVID-19  pandemic, Greenhouse Internists has strived to keep our patients and employees safe by implementing numerous safety measures, such as allowing more time between patient visits to ensure social distancing and time for disinfecting exam rooms, screening all patients before entering the office, offering and telehealth appointments, and requiring an appointment to enter the office.   (To review all COVID-19 – related office information and policies, click here).

As COVID-19 cases are increasing across the country, we have re-evaluated our office policies and have decided on the following changes:

1.  We will move towards more telehealth appointments (phone or   video) as needed to maintain social distancing in the office.

2.  We will add and/or change the COVID-19 screening questions   as we continue to follow state and local guidance. We ask that all   patients/visitors are patient during the screening process and   answer each question thoughtfully and thoroughly.

3.  All patients who visit the office without an appointment will be   told that they must call the office to discuss their concern. No   concerns will be addressed at the door.


Masks must be worn the entire time you are in the office.  If you don’t think you will be able to wear a mask correctly (covering your nose and mouth) the entire time you are in the office, then you should schedule a telehealth visit instead.

Thank you for your cooperation.  Please stay safe and healthy.

Click the following links to learn more:

City of Philadelphia COVID-19 Guidelines for the Holidays
Caring for someone at home
Coronavirus Testing Sites
What to do if you are sick
Coronavirus Questions and Answers


If you have traveled, or plan to travel, to an area where there are high amounts of COVID-19 cases, it is recommended that you stay at home for 14 days upon return to Pennsylvania.  Greenhouse Internists requires that you wait at least 14 days upon your return to PA before you can visit the office.  If you need to speak to a provider sooner for a health concern, you would need to schedule a telehealth appointment.   For the latest travel guidance, click here.


Currently, flu shots are being offered on Wednesday and Friday afternoons by appointment only.  Please call the office or request an appointment for a flu shot by using the Patient Portal.  (Log into the portal and select Appointments, New Appointment).
Important Information:
Greenhouse Internists uses a third party vendor, Vaxcare, for our vaccines.  We can only administer vaccines that are covered in Vaxcare’s system.  For example, insurance plans such as Keystone First, Health Partners, and Amerihealth are not contracted with Vaxcare.  We will check your eligibility before scheduling your appointment.  If you are ineligible for a vaccine from Vaxcare, we recommend that you call your insurance company to verify your coverage and then go to a local pharmacy for the vaccine.



Tryphena Hsi, CRNP, joined Greenhouse in March 2020.  She has worked as a Nurse Practitioner for over 7 years and has much experience in primary care and women’s health.  Most recently she practiced at Covenant House Health Services, where she provided primary care services to adult and geriatric patients with multiple chronic illnesses. Tryphena is passionate about patient education and empowering patients to make positive health changes. Tryphena is available to see patients for urgent and follow up needs in the office or by virtual visit.

Diane Fox

Diane Fox, CRNP, joins us with over 20 years as a Nurse Practitioner, with most of her experience in primary care.  She has her nursing degrees from La Salle and Penn State Universities. Most recently, she provided primary care to residents of Abramson Senior Care, managing acute and chronic conditions, as well as palliative and hospice care.  Diane is especially interested in geriatrics, palliative and advance care planning, and educating patients to help them make positive health behavior changes.  Outside of work, Diane enjoys lacrosse, baking, and spending time with her family and friends.


Effective January 1, 2019, Labcorp is Aetna’s preferred lab.  This means that if you need to get labs, patients with any insurance plan except Health Partners, will have orders sent to Labcorp to get their lab tests.  Patients with Health Partners insurance plan will continue to use Quest for their labs.


Click on your doctor’s photo below to read their bio.

Elizabeth Fabens

Elizabeth Fabens, MD 

Dan Peterson

Daniel Peterson, MD