Umair A. Shah, MD, MPH <br> <small>Executive Director</small> Umair A. Shah, MD, MPH
Executive Director

Biosketch Long | Short 

 Welcome to Harris County Public Health - Harris County community members!

It is my great pleasure to welcome you to Harris County Public Health (HCPH), the county health department for Harris County (TX) – the 3rd most populous county in the U.S., one of the fastest growing, and home to Houston (4th largest city).

We are busy and diverse in every way imaginable. Our agency is made up of over 700 public health professionals who are proud and passionate of the work they do, and are dedicated to improving the health and well-being of Harris County residents and the communities in which we live.

HCPH has an annual budget of approximately $100 million with a mix of federal, state, and local funding dollars. Harris County Commissioners Court reviews and approves the budget for HCPH.

So what is public health?

Public health has been defined by the Institute of Medicine (IOM) as “what we as a society do collectively to assure the conditions in which people can be healthy.”

This means that public health is concerned not only with what happens within the healthcare system (that is, in hospitals, clinics, emergency rooms, etc.) but also what occurs outside of the healthcare system - in the community.

In fact, much of what helps determine the health of our community relates to activities happening where people live, learn, work, worship and play. It is about what happens in the community including those factors such as education, socio-economic status, housing, transportation, and environment to name a few.

Moving forward . . .

While many of these factors may not directly be considered a part of public health, increasingly these factors are seen as what drive health. They are all pieces to the larger puzzle of what shapes our community’s health and thus important to our efforts. We are equally committed to achieving health equity – the best health possible for ALL of our residents.

I hope you will find our website useful (we are continuing to make improvements for our viewers!). It provides information to help promote your health, the health of those around you, and the health of OUR community. We are all in this together!

Indeed, we have a fantastic community in Harris County, yet challenges remain – please join us in our goal to make Harris County the healthiest community possible!


Dr. Shah's signature

email: umair.shah@phs.hctx.net


Gwen Sims, Med, RD, LD
Deputy Director

Gwen Sims has been recently appointed as the Deputy Director for Harris County Public Health (HCPH). Before being appointed to this position, she was the Director of Nutrition and Chronic Disease Prevention (NCDP), a division established in September 2014 at HCPH which serves Harris County, Texas – the third most populous county in the United States.

Internally at HCPH, Ms. Sims serves as Champion for the Collaborative Activities, Recognition & Events (CARE) Workgroup, which focuses on engaging and improving employee morale. In addition, Ms. Sims provided oversight and guidance for other departmental work, including the Drug Abuse Prevention (DAP) Taskforce; the Chronic Disease Tag-Up, which monitors activities across the department; the Injury Prevention Tag-Up; the Social, Emotional and Mental (SEM) Well-Being Tag-Up; the Maternal & Child Wellness Taskforce; Obesity Reduction and Tobacco Cessation community projects; as well as Health Education, specifically school health programs. She serves as the co-project director for Healthy Living Matters (HLM), a collaborative addressing childhood obesity in Harris County through policy and environmental change by convening community partners to share and implement best practices related to nutrition and physical activity. She was also instrumental in the creation of the Serenity Room, which is available to employees for meditation, prayer, or pumping for breastfeeding mothers.

In an effort to build and maintain partnerships, Ms. Sims serves on the boards of Cancer Alliance of Texas (CAT) – Chair Elect, whose mission is “to engage organizations, agencies, institutions and individuals to work collaboratively to reduce the impact of cancer in Texas and promote the Texas Cancer Plan”; L.I.F.E. Houston (Vice-President), which provides emergency food and formula, as well as infant nutrition education to families in need; and Houston Recovery Center Technical Assistance Group (TAG). She was also a member of BridgeUp at Menninger and the Houston SNAP Taskforce, and she currently serves on the Improving Maternal Health Steering Committee. She is a Senior Fellow of the Gulf Coast Chapter of the American Leadership Forum (Class XLVI – Healthcare).

Ms. Sims is a registered and licensed dietitian who joined the health department in 1997. She is a graduate of Southern University and A&M College in Baton Rouge, Louisiana with a Bachelor of Science in Human Nutrition and Foods and a Master's Degree in Education.

Dana Beckham, DVM, MPH, MBA<br> <small>Director - Office of Science, Surveillance and Technology</small> Dana Beckham, DVM, MPH, MBA
Director - Office of Science, Surveillance and Technology

Welcome to the new Office of Science, Surveillance Technology!

Science, surveillance, and technology are cornerstones of modern public health. Applying the scientific method to the data we collect allows us to confidently make decisions to improve your health and well-being. Surveillance data gives Harris County Public Health direct insight into threats to population health. Technology and innovation provide or accelerate solutions to difficult problems.

The Office of Science, Surveillance and Technology (OSST) enhances HCPH’s ability to detect problems, conduct research, come up with creative solutions, and advance the science of an academic health department. These three branches come together to form the foundation of precision public health, allowing HCPH to make sound decisions to improve the health and well-being of Harris County residents.

Dr. Dana Beckham received her Doctor of Veterinary Medicine degree from Tuskegee University, her Master of Public Health and her Master of Business Administration from Benedictine University. She has over 20 years of experience working at the state and local public health departments in various fields, including zoonosis control, public health preparedness, community health services, infectious diseases and epidemiology.

In 2015, Dr. Beckham joined HCPH as manager of the Tuberculosis (TB) Elimination Program. She later served as the manager for the Epidemiology Program. In 2018, she became the director of the Office of Science, Surveillance, and Technology (OSST). She is Lean Six Sigma Green Belt Certified and co-chair of HCPH One Health Conference.

Email: Dana.Beckham@phs.hctx.net

Michael W. “Mac” McClendon<br /><small>Director - Office of Public Health Preparedness & Response</small> Michael W. “Mac” McClendon
Director - Office of Public Health Preparedness & Response


Welcome to the Office of Public Health Preparedness and Response (OPHPR)!

Harris County Public Health (HCPH) is the primary agency responsible for protecting the public’s health in the event of a widespread public health emergency within Harris County. A public health emergency is defined as an immediate threat from a naturally occurring or intentional event that poses a high risk of fatalities or serious long-term disability to large numbers of people.

Within HCPH, OPHPR works with numerous jurisdictional partners, emergency responders, private and public sectors, NGO’s, and volunteer organizations to mitigate, prepare for, respond to, and recover from the effects of emerging infectious diseases, pandemics, chemical, biological/radiological emergencies along with other non-specific public health emergencies.

OPHPR maintains plans, standard operating guides (SOG’s) and supporting documents that guide preparedness, mitigation, and response activities. OPHPR actively engages both our employees and volunteer support partners in training through classroom sessions, drills, and exercises to help plan and prepare for public health emergencies.

For more information about the Office of Public Health Preparedness and Response, please call (713) 439-6179.

Email: Michael.McClendon@phs.hctx.net

Elizabeth Perez, MPH<br /><small>Director - Office of Communications, Education & Engagement</small> Elizabeth Perez, MPH
Director - Office of Communications, Education & Engagement


Welcome to the Office of Communications, Education, and Engagement (OCEE)!

Our job is to tell the Harris County Public Health story—a diverse narrative comprising people, place, and experience that defines Harris County, and to provide support to HCPH amid a growing population.

How do we do this?

We help, assisting our departments, programs, clinics, and offices in getting the word out about their own stories and programs that are in neighborhood.

We collaborate, working across divisional and organizational boundaries to communicate consistently and strategically.

We educate, and share imparting stories to our numerous communities and audiences, both internal and external, using a variety of print, social media, and electronic means.

We engage, which means that you are the most vital piece to helping us ensure that everyone has the opportunity to reach their optimal health.

We are here to support our leadership, divisions, offices, and the community. To learn more about us or to invite us to a community event, call: (713) 439-6246. For media requests, call: (713) 439-6911.

Email: elizabeth.perez@phs.hctx.net

William Hudson, MPH, MSMOB<br><small>Director - Office of Finance and Support Services</small> William Hudson, MPH, MSMOB
Director - Office of Finance and Support Services

Welcome to the Office of Finance and Support Services!

William Hudson, Director, Office of Finance and Support Services, has over 15 years of healthcare / public health experience, and is responsible for the agency’s operational and fiscal integrity. His responsibilities include Human Resource, Finance, Operations & Logistics, Innovation and Project & Business Technology. His experience in each of these areas brings a unique level of breadth and understanding to the organization.

Prior to his promotion, he served as the agency’s Director for Health Transformation and Director of the Public Health Innovations Lab at Harris County Public Health. In his previous roles, he was responsible for the operational oversite and strategy of the department's 1115 Wavier Medicaid Project portfolio, Federal-Title X-Family Planning and Reproductive Health programming, Center for Disease Control and Prevention (CDC) Childhood Lead Poisoning Prevention Program, and the Public Health Innovation Accelerator Program.

He holds a Masters of Public Health (MPH) and a Master of Management in Organizational Behavior (MSMOB) from Benedictine University, and a Bachelor’s of Science in Biology with a minor in Chemistry from Texas Southern University, and is completing a Master’s in Business Administration (MBA) program from the University of Louisiana- Lafayette, Moody School of Business.

In addition to his formal education, he has completed executive education programs from The Institute for Strategy and Competitiveness- Harvard Business School, MIT Sloan, and the University of Oxford, Said Business School. He is a Fellow of the Academy for HealthCare Management, Certified Lean Six Sigma Black Belt, and a National Association for Healthcare Quality (NAHQ) Board Certified Professional in Healthcare Quality (CPHQ). He also holds additional certifications from the Agency for Healthcare Research and Quality (AHRQ), Healthcare Financial Management Association (HFMA), and the Healthcare Information and Management Systems Society (HIMSS).

Aside from his primary role with Harris County, William holds multiple advisory roles with institutions such as the Texas Medical Center Innovation Institute, Houston Ion, and the Texas Southern University- College of Science Engineering and Technology, and serves as a graduate program evaluator for the Western Governors University Health Leadership Program, as well as adjunct faculty in the Texas Southern University- Barbara Jordan- Mickey Leland School of Public Affairs.

Email: William.Hudson@phs.hctx.net

Michael R. Schaffer, MBA<br /><small>Director - Environmental Public Health Division</small> Michael R. Schaffer, MBA
Director - Environmental Public Health Division


Welcome to the Environmental Public Health Division!

As the Director of Environmental Public Health, my mission is to effectively utilize the resources I have to do the best I can to protect the public's health in Harris County by: 

  • Permitting and inspecting food establishments and public pools
  • Ensuring the integrity of drinking water
  • Abating neighborhood nuisances
  • Having safe pools to swim in
  • Minimizing lead-based paint in target area homes

As the regulating authority in these areas, we will seek compliance through education and enforcement efforts. It is the responsibility of owners to make sure their properties follow both local and state laws. These laws were put into effect to protect the public’s health, and I will do everything I can to ensure it is protected.

I encourage everyone in Harris County to report any foodborne illness (a disease caused by consuming contaminated food or drink), nuisance conditions of properties, contaminated water supplies, or swimming pools that are not safe to swim in. My team is here for the residents of Harris County, and they are committed to ensuring their safety.

For more information about the Environmental Public Health Division, please contact (713) 274-6300.

Email: Michael.Schaffer@phs.hctx.net

Sherri Onyiego, MD, PhD
Director - Nutrition & Chronic Disease Prevention


Dr. Sherri Onyiego currently serves as the Director for Nutrition & Chronic Disease Prevention in the Nutrition and Chronic Disease Division (NCDP). Dr. Onyiego is a Board Certified Family Physician with over 15 years of clinical experience in managing and treating chronic diseases as it relates to individual patient care as well as population health. She also has academic, research and administrative experience in previous and current roles.Dr. Onyiego joined HCPH in October 2017, and her role of HCPH involves clinical operational oversight and programmatic expansion of the Chronic Disease Prevention, Mental/Behavioral Health Units, Nutrition and WIC services, Community Dental services. In addition, Dr. Onyiego also serves as the alternate Local Health Authority assisting the Executive Director of Harris County Public Health.

Dr. Onyiego earned a doctorate in pharmacology from Meharry Medical College in Nashville, Tenn. with a research focus on novel compounds targeting HIV-1. She attended medical school at Ross University School of Medicine. She completed her residency training in family medicine at Louisiana State University Health Sciences Center and later went on to conduct a fellowship in HIV medicine at the University of Texas at Houston.


Dr. Onyiego is a member of several professional, social, and community organizations particularly, the American Academy of Family Physicians; Texas Academy of Family Physicians; Harris County Academy of Family Physicians, andthe American Academy of HIV Medicine. Dr. Onyiego sits on a number of professional workgroups and committees. She serves on the Board of Directors for Harris County Academy of Family Physicians.

Michael White, DVM, MS<br /><small>Director - Veterinary Public Health Division</small> Michael White, DVM, MS
Director - Veterinary Public Health Division


Welcome to the Veterinary Public Health Division (VPH)!

Our primary mission is one of public health - protecting you, the residents of unincorporated Harris County, from zoonotic diseases and injuries caused by animals. We accomplish this through:

  • Bite case investigations
  • Disease surveillance
  • Animal law enforcement
  • Stray animal control
  • Education
  • Rabies vaccinations
  • Policy development
  • Registration of dogs and cats within unincorporated Harris County

We also work in close partnership with the community to create a safe, healthy and caring environment for people and animals.

VPH is committed to providing humane, compassionate, quality care to animals in our facility. We attempt to return lost pets to their owners and strive to place as many of our unclaimed shelter animals as possible into new “forever homes” through our adoption program, the help of our rescue partners and transfers to other animal sheltering agencies. For those animals that need a little extra “TLC” or veterinary care before they are suitable for adoption, we have a robust animal fostering team made up of dedicated staff and volunteers.

Educational programs are ongoing to bring awareness to the pet overpopulation problem in Harris County and to promote responsible pet ownership. We advocate spaying and neutering, microchipping, and vaccinating as part of the solution to the stray animal problem. However, we alone cannot solve the problem. That is why we invite you to join the effort in educating the community on the importance of responsible pet ownership.

It is my pleasure to work with the dedicated group of individuals employed at VPH. Our staff members continue to perform their jobs with efficiency, integrity and compassion. I am impressed daily by their amazing loyalty to VPH’s mission of protecting the public from zoonotic disease and injury from animals as well as providing humane care to the animals in their charge. Through continued collaboration and coordination with our partners, we are committed to being a shining example of care and best practices for all sheltering facilities.

For more information about VPH, please call (281) 999-3191.

Email: Michael.White@phs.hctx.net

Michael Ha, MBA
Director - Disease Control & Clinical Prevention


Welcome to the Disease Control and Clinical Prevention Division!

Harris County, Texas, the community we call home, continues to be among the fastest growing areas of the nation - in population, job creation, and economic opportunity. With this progress comes the responsibility to make sure our community is an excellent place to live, work, and raise a family.

The Disease Control and Clinical Prevention (DCCP) division includes a wide range of clinical and prevention activities. We provide immunizations, family planning services, child dental services, TB programs, HIV-related services, refugee health screening, and other services. We also watch disease trends, work to reduce preventable illness and injury, and promote healthy lifestyles that can decrease chronic disease.

The division includes over 300 public health professionals. They are from a variety of health care backgrounds, and they give their best to achieve our mission to promote, prevent, and protect.

We bring knowledge and guidance as a public health department. Our real success, however, depends on our connection with people, families, and organizations throughout Harris County. Together, we will meet future challenges and build the healthiest community possible.

For more information about the Disease Control & Clinical Prevention, please call (713) 439-6000.

Email: Michael.Ha@phs.hctx.net



Marva Gay, M.A., J.D.<br> <small>Legal Counsel</small> Marva Gay, M.A., J.D.
Legal Counsel

Senior Assistant County Attorney Marva Gay joined Harris County Public Health as its full-time in-house legal counsel in September 2014 through an arrangement with the Harris County Attorney’s Office (HCAO).She handles various legal affairs from contracting and transactions to public health law counsel, statute review, and policy input allowing for more seamless integration of public health law with public health planning and practice.

Ms. Gay has been with the Harris County Attorney’s Office since 1995, first within the General Counsel Division and moving up to be the Managing Attorney for the Public Law Practice Group.Her major clients have included the Harris County Office of Emergency Management and Homeland Security, the Sheriff’s Medical Unit, the Harris County Hospital District’s Community Health Choice and Harris County Public Health.Prior to joining HCAO, Ms. Gay was in private practice in Louisville, where she focused on healthcare and non-profit related law. She holds undergraduate and master’s degrees in journalism from the University of Kentucky and her JD from the University of Miami.She is licensed to practice in Texas, Kentucky and Florida. Ms. Gary is a member of the Houston Bar Association and has served as a board member of both the Health Law Section and the Animal Law Section.

Email: Marva.Gay@cao.hctx.net

Chris Fredregill
Director - Mosquito & Vector Control

Welcome to the Mosquito and Vector Control Division

Chris Fredregill currently serves as the Interim Director of the Mosquito and Vector Control Division (MVC). Chris comes to the position with over 17 years of medical entomology and public health experience which he uses to ensure that MVC constantly strives for innovation and creative approaches to control mosquitoes, while leveraging collaborations and grants into sustainable capacity.

Prior to this role, Chris held several positions throughout MVC including: Field Operations Manager, Research Entomologist and Larviciding Operations Entomologist. During these appointments, Chris oversaw collaborations with the Army Corps of Engineers and the Port of Houston, incorporated novel larviciding technologies and directed the field activities of the division. He has additionally led MVC in collaborations with various institutions both academic and commercial including Texas A&M, University of Texas Medical Branch, Baylor College of Medicine, Texas Department of State Health Services and Centers for Disease Control & Prevention.

Chris received his Bachelor of Science degree from Texas A&M University in Biomedical Sciences and Entomology. He has also earned his Lean Six Sigma Blackbelt certification and is an active member of the Texas Mosquito Control Association and American Mosquito Control Association.

Mission Statement

HCPH Mosquito & Vector Control Division protects the health and well-being of county residents through surveillance, control, education, research, and technology to prevent and control mosquito-borne diseases such as West Nile Virus (WNV) and St. Louis Encephalitis (SLE).

For more information about Mosquito Control, please call (713) 440-4795.

Wendie Veloz<br><small>Director - Office of Policy &amp; Planning</small> Wendie Veloz
Director - Office of Policy & Planning

Welcome to the Office of Policy and Planning!

It is an awesome privilege to work in the field of public health, a profession that I absolutely love. An incredible wealth of information is at my fingertips, constantly challenging me to stretch my imagination and to think hard about how the health potential of communities, neighborhoods, and families can more fully be achieved. Interestingly enough, public health seeps into my personal life – from decisions about my child’s safety seat to whom I vote for in an election. Health and well-being for individuals and communities is on the forefront of my mind.

I credit this influence to the Harris County Public Health (HCPH) Office of Policy and Planning (OPP). Since 2005, I’ve enjoyed working in the office at a strategic level on various complex and evolving public health issues across the department ranging from emergency preparedness to childhood obesity. OPP relies on the best evidence available to lead and guide comprehensive planning efforts that result in actionable strategies for improving and protecting the health of Harris County residents.

These efforts are grounded in health data and the voices of residents and other stakeholders. As part of OPP’s assessment role, we regularly take a snapshot of the health landscape to identify and prioritize needs in Harris County, realize untapped or underutilized community assets and work with partners to bring about change that will produce health benefits for all residents. As actions are being performed, HCPH wants to know what works and what is not working, so OPP maintains a department-wide evaluation framework to support ongoing monitoring of programmatic outcomes and quality improvement.

Policy is often an effective vehicle for speeding up progress and achieving the gains in health we want to achieve across millions of residents in Harris County. As the Office Director, I serve as the department’s legislative liaison and therefore work on various policy initiatives – legislative, regulatory or voluntary – at local, state and national levels.

I am fortunate to work alongside colleagues who inspire me to do better when I watch how they work tirelessly on improving conditions in our day-to-day environments to make good health achievable for all, regardless of one’s income, level of education or life circumstances. It is equally inspiring to see residents from all walks of life grant us access into their communities and get excited about the possibilities for better health and quality of life. Each day, I am reminded that public health REALLY…TRULY matters.

For more information about the Office of Policy and Planning, please call (713) 439-6000.