Yolo County staff investigate individual reports of highly contagious, or communicable disease and take whatever steps are necessary to control outbreaks in the community. These staff ensure that the affected person and their close personal contacts receive medical treatment, develop programs to prevent future disease outbreaks, provide public and professional education, and collaborate with other organizations at the State and Local level to control the spread of disease.

Once Public Health receives a disease report, an investigation is started to:

• Confirm the diagnosis and the original source of the disease
• Verify the disease
• Locate affected persons
• Provide affected persons with information about the disease
• Look for any common mode of transmission between affected persons
• Provide affected persons and the public, if necessary, with information about the disease, including: symptoms, how diagnosis is confirmed, how the disease is spread, and how to prevent it.

Sometimes Infectious Disease staff work with other agency staff to control or stop an outbreak. For example, cases involving a restaurant or day care facility will require coordination response between the Communicable Disease staff and Environmental Health.

For questions or to return a call regarding infectious disease: (530) 666-8670

For questions about Wellness Vending Machines: (530)666-8684

For questions about Immunizations: (530) 666-8552

Find flu vaccines at www.vaccines.gov/find-vaccines

Want to save time? Fill out and print the Consent & Screening Form(PDF) | Spanish Form(PDF)

• Your doctor’s office or child’s pediatrician may offer vaccines
• Local pharmacies
• Use the Find a Clinic tool (This link is for COVID and Flu clinics only)
• 2024 Immunization Clinics in Yolo County (update link)
• For Partnership (Medi-Cal) members, contact Members Services at (800) 863-4155

If you do not have insurance, find out if you or your child is eligible for Medi-Cal

If you cannot find your immunization record, here are a few places to start: 

• Digital vaccine record portal: Request Record
• Doctor's office or clinic where shots were given most recently.
• Schools that your child attended.
• You may also be able to get help from the California Immunization Registry (CAIR). Find out if your child's records are included in the immunization registry.

Infant Immunization Schedule

Children Immunization Schedule 0-18 years old

California school immunization law outlines the immunizations required for school and childcare entry. These resources will help you to comply with state of California immunization requirements.

Immunization Requirements for Child Care

Immunization Requirements for K-12

7th grade

Are your child's classmates vaccinated? See immunization rates for schools in your area: Child Care, Kindergarten, 7th Grade.

For any questions on routine immunizations, please call (530) 666-8552

If you are unsure which immunizations you need, or where to go for immunizations, our Immunization Program staff are happy to help!

• Your doctor’s office
• Communicare Safe Care Clinic
• Planned Parenthood
• Free at-home STI and HIV testing

The Public Health Department offers Partner Services. Partner Services helps to inform someone of a potential exposure to HIV or an STI. It is free, voluntary, and confidential. As a notified partner, you will receive a phone call from one of our Communicable Disease Specialists and can choose whether to be tested and can receive counseling about how to avoid future exposure to HIV and STIs.

If you have been diagnosed with an STI and want help notifying your sexual or needle-sharing partners, contact us at (530) 666-8670 for the following Partner Services:

• Obtain materials on how to notify your partners
• Schedule a dual notification with a trained Public Health HIV/STI counselor to help you notify your partner
• Request a trained Public Health HIV/STI counselor to notify your partner anonymously 

Pre-Exposure Prophylaxis or "PrEP" is an HIV prevention option for people who do not have HIV but are at increased risk. PrEP is highly effective for preventing HIV if used as prescribed. If you combine PrEP with condoms and other prevention methods the likelihood of getting HIV is even lower.

 How can I get PrEP?

• If you have health insurance and have a healthcare provider, ask your doctor to
• If you have health insurance and need to find a PrEP provider, visit PleasePrEPme.org to find a provider near you.

Post-Exposure Prophylaxis (PEP) is an HIV prevention option that should be used only in emergency situations. PEP must be started within 72 hours after a recent possible exposure to HIV.  If you think you have been exposed to HIV in the last 72 hours, go to the nearest Urgent Care facility or Emergency Room for assistance.

For resources and to learn more about PrEP/PEP visit PrEPisLiberating.org 

Yolo County offers a variety of free health and wellness tools via our five Wellness Machines. Items in our Wellness Machines are available to everyone, and prioritized for people who are uninsured or underinsured, people experiencing homelessness, people who use drugs and people who may witness a drug overdose, and people with limited agency and access to health supplies.

Please take only what you need and consider obtaining items through other sources (health insurance, out of pocket) if you are able, so that we can continue to make items available to people who need them most.

• West Sacramento Yolo County Health & Human Services 500 Jefferson St., Building B (Lobby) West Sacramento
• Esparto Regional Library, 17065 Yolo Ave, Esparto
• Davis Yolo County Health & Human Services 600 A St. Davis
  • Test Kits are available for symptom free residents at:
    •  Mary L Stephens Library 315 E 14th St. Davis
    • Yolo County Health & Human Services 600 A St. Davis (Front Desk)
• Winters City Hall 318 1st St, Winters
• Woodland Test Kits are available for symptom free residents at:
  • Yolo County HHSA Woodland Service Centers, 25 N. Cottonwood St. Woodland (Lobby Front Desk)
  • All other wellness products are available for pick up by arrangement for Woodland residents contact HHSA.PrimaryPrevention@yolocounty.gov or (530)666-8684

Vending Machine Flyer English, Spanish, Russian(PDF)

Report Vending Machine Concerns & Feedback here. 

 For questions or concerns, please contact HHSA.PrimaryPrevention@yolocounty.gov or (530)666-8684

Vaccine information

Updated COVID-19 vaccines protect against currently circulating variants and help protect against severe illness from COVID-19. It is recommended that everyone 6 months and older get an updated 2024-2025 COVID-19 vaccine. 

To get an updated COVID-19 vaccine, talk to your healthcare provider or local pharmacy. COVID-19 vaccines are covered by all health insurance. People without health insurance can get free vaccines at federally-qualified health clinics and most pharmacies.

COVID Vaccine frequently asked questions 

Treatment

COVID-19 treatments work best when taken soon after symptoms begin. Get tested as soon as you notice symptoms. If you test positive, contact your healthcare provider to see if you qualify for oral medication to treat COVID-19.

Data

COVID in wastewater shows the daily concentration of SARS-CoV-2, the virus that causes COVID, present in county wastewater treatment facilities serving people who live and work in Yolo County. Data from wastewater analysis can be used as an indicator of the level of transmission of COVID in the community and track the prominence of new variants.

Hepatitis A is a liver disease caused by the hepatitis A virus. Hepatitis A virus is transmitted through the “fecal-oral” route. If a person with hepatitis A does not wash their hands well after going to the bathroom they can contaminate objects, food, or drinks. Someone else can be infected when they put these items into their mouth.

Hepatitis A virus infection can cause a mild illness lasting a few weeks to a severe illness lasting several months. People with liver disease, including chronic hepatitis B or C infection, are at greater risk of developing severe disease as a result of hepatitis A infection. People over 50 years old are also at greater risk of developing severe disease. Unlike hepatitis B and C, hepatitis A does not cause a chronic infection.

Information flyers:

Hep A Information Flyer – English
Hep A Information Flyer – Spanish
Hep A Information Flyer – Russian

Hepatitis B is a liver disease that results from infection with the hepatitis B virus. It can be spread in three ways:

1. Birth: From a woman with chronic hepatitis B to her child at birth
2. Blood: Through direct contact with contaminated blood, including sharing needles and syringes
3. Sex: Through condomless sexual contact with an infected person

Testing and screening

Testing for hepatitis B is recommended for:

• People born in Asia, Africa, and other regions with moderate or high rates of Hepatitis B
• Unvaccinated people whose parents are from regions with high rates of Hepatitis B
• Anyone having sex with a person infected with Hepatitis B
• People who live with someone with Hepatitis B
• Men who have sexual encounters with other men
• People who inject drugs
• All pregnant women
• People with HIV infection
• People on hemodialysis
• People who receive chemotherapy or other types of immunosuppressive therapy

  Most people with chronic hepatitis B infection appear healthy and do not exhibit any symptoms. You can take a short risk assessment to see if you are at risk for chronic hepatitis B infection. The only way to diagnose hepatitis B is by a blood test.

Vaccine recommendations 

Hepatitis B screening and vaccination are fully covered by most insurance plans. Ask your doctor about a hepatitis B test. The best way to prevent Hepatitis B is by getting vaccinated. The Hepatitis B vaccine is typically given as a series of 3 shots over a period of 6 months. The entire series is needed for long-term protection.

• Infants and Children
  • The vaccination schedule used for recommendations in the US includes vaccination with at least 3 doses of hepatitis B vaccine starting at birth
  • If these doses are not administered when a child is a baby, they are recommended to follow a “catch up” schedule and get them through age 18

• Students in California California law dictates that hepatitis B vaccination is required for school entry into childcare and K-12 education

• Adults: The vaccine is recommended for people living with someone infected with hepatitis B, travelers to certain countries, and healthcare and public safety workers exposed to blood. People with high-risk sexual behaviors, men who have sex with men, people who inject drugs, and people who have certain medical conditions, including diabetes, should talk to their doctor about getting vaccinated.
  • Adult Immunization Schedule

Every person aged 6 months and older needs the flu vaccine, every year.

The flu shot is a safe, effective way to reduce your chance of ending up in the hospital with severe flu.

Each winter, people sick with flu crowd hospitals and urgent care clinics. The flu vaccine offers many months of protection but does not last forever. Also, the strains of influenza in the community change over time. It is important to get the new vaccine every year.

Where to get a flu shot

Most insurance companies fully cover flu vaccines. The easiest way to get a flu vaccine is to make an appointment at a local pharmacy or with your healthcare provider

Yolo County offers a limited number of free flu shots at clinics each fall. See Immunization page for more information.

How to prevent the flu

You can take the following steps to protect yourself and your loved ones from flu:

• Get a flu vaccine
• Cover your nose and mouth with a tissue or your elbow when you cough or sneeze
• Avoid touching your eyes, nose, or mouth
• Wash your hands often with soap and water or alcohol-based hand rub
• Try to avoid close contact with sick people
• If you are sick, stay home from work or school
• If you are sick, monitor your symptoms and contact your medical provider if your symptoms are getting worse
• If you are seriously ill and at risk for complications from the flu, contact your medical provider because you may need additional treatment or hospital care

Flu information

• Influenza, also called flu, is a contagious respiratory illness caused by influenza viruses. It is not the same as the common cold, which is caused by different viruses. It is not COVID-19, which is also caused by a different virus.
• To be fully protected, you and your family members will need to get vaccinations for both COVID-19 and the seasonal flu.
• Flu symptoms can be similar to those of the common cold but are usually more severe. Learn more about the difference between colds and flu. Learn more about the difference between COVID-19 and flu.

With widespread outbreaks of measles happening in the United States and internationally, and local cases transmitted within Yolo County, the chance of exposure to measles is increased at this time.

Measles is a highly contagious viral infection that spreads from person-to-person. A person with measles can spread the disease to others even before they have any symptoms. Most people who have not been immunized against measles will get it if they have contact with the virus.

The biggest risks for measles exposure for Yolo County residents are international travel, domestic travel through international airports, and contact with international visitors. The international travel associated with the 2019 California cases include India, Cambodia, Thailand, Philippines, Vietnam and the Ukraine.

The best way to keep from getting and spreading measles is to get the measles immunization. Measles immunization is available at your doctor’s office, local pharmacy or health clinic. If you do not know if you are immune to measles, see our frequently asked questions.

If you think that you or someone in your family has measles or has been exposed to measles, contact your doctor's office by phone right away. Tell them that you might have measles before you go in, so they can take steps to prevent other patients and staff from being exposed.

Symptoms

Measles can cause these signs of disease:

• High Fever (over 101ºF)
• Cough
• Runny nose
• Red watery eyes
• A rash that starts on the face and spreads to the rest of the body

Measles is spread through a cough or sneeze by a person with measles and can still infect others 2 hours after the infected person has left a room. Persons with measles are contagious from 4 days before until 4 days after the rash appears. The incubation period for developing measles is up to 21 days after being exposed to someone else who has the disease.

For Travelers

• International Travel Information and Notices (CDC)
• "Think Measles" | "Piense en el Sarampíon"

Additional Resources

• California Department of Public Health
• Centers for Disease Control and Prevention

Mpox (formerly Monkeypox) is a rare disease caused by infection with the monkeypox virus. mpox virus is part of the same family of viruses as variola virus, the virus that causes smallpox. Mpox symptoms are similar to smallpox symptoms, but milder, and MPOX is rarely fatal. MPOX is not related to chickenpox.

Symptoms

Mpox might start with symptoms like the flu,

• fever
• low energy
• swollen lymph nodes
• general body aches
• 1 to 3 days(sometimes longer) after the appearance of fever, the person can develop a rash or sores 

The sores will go through several stages, including scabs, before healing. They can look like pimples or blisters and may be painful and itchy. The rash or sores may be located on or near the genitals (penis, testicles, labia, and vagina) or anus (butt) but could also be on other areas like the hands, feet, chest, and face. They may also be limited to one part of the body. People with mpox may experience all or only a few of these symptoms. Most with mpox will develop a rash or sores. Some people have reported developing a rash or sores before (or without) the flu-like symptoms.

How Mpox spreads

Mpox spreads in a few ways:

• Mpox can spread to anyone through close, personal, often skin-to-skin contact, including:
  • Direct contact with MPOX rash, scabs, or body fluids from a person with Mpox.
  • Touching objects, fabrics (clothing, bedding, or towels), and surfaces that have been used by someone with mpox.
  • Contact with respiratory secretions.

• This direct contact can happen during intimate contact, including:
  • Oral, anal, and vaginal sex or touching the genitals (penis, testicles, labia, and vagina) or anus (butthole) of a person with mpox.
  • Hugging, massage, and kissing.
  • Prolonged face-to-face contact.
  • Touching fabrics and objects during sex that were used by a person with mpox and that have not been disinfected, such as bedding, towels, fetish gear, and sex toys.

• A pregnant person can spread the virus to their fetus through the placenta.

A person with mpox can spread it to others from the time symptoms start until the rash has fully healed and a fresh layer of skin has formed. The illness typically lasts 2-4 weeks.

What to do if you think you have Mpox

If you have a new or unexplained rash or other symptoms, seek medical care for further testing and evaluation. If you do not have a healthcare provider or health insurance, care may be available at CommuniCare Health Centers, Winters Healthcare, Elica Health Centers, Community Medical Centers, or North Valley Indian Health. Limit your contact with others while awaiting medical care and test results. 

Mpox Vaccine

Vaccination helps to protect against mpox when given before or shortly after an exposure. JYNNEOS and ACAM2000 are two mpox vaccines currently available in the United States. Yolo County Public Health has received an ample supply of JYNNEOS and has shared these doses with local healthcare providers. JYNNEOS is a 2-dose vaccine series given 28 days or more apart. A person is considered to be fully protected against mpox 2 weeks after their 2nd dose. You can read more about the JYNNEOS vaccine on the CDC website.

While there is currently adequate vaccine supply, there are no longer "eligibility" criteria, and vaccine providers can offer vaccine to any patients who MAY be at risk, and persons who request vaccination should receive it without having to attest to specific risk factors.

Treatment

Antiviral drugs and vaccines developed to protect against smallpox may be used to prevent and treat mpox virus infections.

Antivirals, such as tecovirimat (TPOXX), may be recommended for people who are more likely to get severely ill, like patients with weakened immune systems.

Norovirus is a highly contagious virus and the leading cause of illness (commonly called the "stomach flu") in the United States. Anyone can get infected with this virus and get sick. Some people who are infected with the virus do not have any symptoms at all. For most people who get ill, the symptoms are minor, lasting only a few days. However, Norovirus can cause a more serious life-threatening illness for those who are particularly at risk.

Symptoms will appear within two days after exposure. Most will recover within 1-3 days after symptoms appear.

• Common symptoms include nausea, vomiting, diarrhea, stomach cramps, headache and/or a fever.
• Severe symptoms caused by dehydration include decreased urination, dry mouth and throat, and/or feeling dizzy when standing up.

How is norovirus spread?

Norovirus lives in the stool or vomit of infected people. You can get norovirus from:

• Having direct contact with an infected person (for example, when caring for them or sharing food or utensils with them).
• Eating food or drinking liquids that are contaminated with norovirus.
• Touching objects that are contaminated with norovirus and then putting your unwashed hands in your mouth. 

Because the amount of norovirus needed to infect a person is so small, people can very easily become sick from touching food, drinks, and surfaces contaminated with norovirus. Contamination can happen through direct contact with hands or surfaces that are contaminated with stool or vomit, or by tiny droplets from nearby vomit that can travel through the air.

If you think you have norovirus, stay home until you have been symptom-free for 48 hours without the use of medication. Stay away from others and clean shared surfaces often.

How can I prevent the spread of norovirus?

Hand washing with soap and water is the most important way to prevent the spread of norovirus. Alcohol-based sanitizers are not as effective as washing hands with soap and water.

Thorough cleaning and disinfecting is also important:

• Any surfaces near vomit or diarrhea should be promptly cleaned and disinfected with bleach solution and then rinsed.
• Throw out any food items that may have become contaminated with norovirus.
• Any linens (for example, clothes, towels, tablecloths) that have been soiled to any extent with vomit or stool should be promptly washed in hot water.

What is tuberculosis?

Tuberculosis (TB) is caused by a bacteria spread through the air when an individual with infectious TB disease coughs, sneezes, or speaks. Transmission occurs when others breathe in the bacteria while in close and prolonged contact with a person with infectious TB disease. If treatment is delayed, TB disease can cause serious illness and death. TB is the second leading infectious killer after COVID. Fortunately, it can be prevented, treated, and cured.

 If you have any of the symptoms listed, go see a doctor to find out if you have TB.

 Symptoms can include:

• Cough that lasts more than 2-3 weeks
• Coughing up blood
• Chest pain
• Fever
• Night sweats
• Weight loss

TB is preventable and curable. People at increased risk for TB include:

• People who were born in OR have lived in a country where TB is common
• People who have lived with or spent time with someone who has TB
• People living with HIV or who have received an organ transplant

   

Before you become sick with TB disease, there is a period of time when you have no symptoms even though TB bacteria are dormant inside your body.  This is called latent TB infection (LTBI). LTBI is not contagious. 

When your body can no longer prevent the bacteria from growing, it will multiply and cause TB disease. Individuals with LTBI may become sick with TB disease within weeks to many years after becoming infected. Overall, 5 to 10 percent of people with LTBI develop TB disease over their lifetime; this risk is higher for those with risk factors for progression from LTBI to TB disease, such as undernutrition, HIV infection, and diabetes. Certain behaviors, such as alcohol and smoking, also increase an individual’s risk for developing TB disease. Before you become sick with TB disease, there is a period of time when you have no symptoms even though TB bacteria are dormant inside your body.  This is called latent TB infection (LTBI). LTBI is not contagious.

When your body can no longer prevent the bacteria from growing, it will multiply and cause TB disease. Individuals with LTBI may become sick with TB disease within weeks to many years after becoming infected. Overall, 5 to 10 percent of people with LTBI develop TB disease over their lifetime; this risk is higher for those with risk factors for progression from LTBI to TB disease, such as undernutrition, HIV infection, and diabetes. Certain behaviors, such as alcohol and smoking, also increase an individual’s risk for developing TB disease.

Your doctor can test you for latent TB infection with a blood test. If your blood test is positive, your doctor will order a series of confirmatory tests to rule out active TB. If your doctor confirms that you have active TB, a Public Health Nurse will contact you to support your treatment and to help prevent spread to your loved ones.

West Nile Virus is spread by the bite of an infected mosquito, and is the most common mosquito-borne (transmitted) disease in the United States.

Most people who are bitten by an infected mosquito don’t develop symptoms. Roughly 20% of people develop the flu-like symptoms of West Nile fever, including:

• Fever
• Headache
• Fatigue
• Nausea
• Vomiting
• Body aches
• Occasional skin rash
• Eye pain or swollen lymph glands

  Most people with symptoms will fully recover, but fatigue and weakness can last for weeks or months. In rare cases, West Nile fever develops into a severe illness. Recovery from several illness can take weeks or months, and some neurological effects can be permanent.

There is no specific treatment. Mild symptoms pass on their own. Anyone experiencing severe symptoms should go to the hospital to receive supportive treatment.

• Practice the Sacramento-Yolo Mosquito and Vector Control District’s 7 D’s of Protection:
• DRAIN any standing water that may produce mosquitoes.
• DAWN and DUSK are the times to avoid being outside. This is when mosquitoes are most active.
• DRESS appropriately by wearing long sleeves and pants when outdoors.
• DEFEND yourself against mosquitoes by using an effective insect repellant, such as DEET, Picaridin, or Oil of Lemon Eucalyptus. Make sure you follow label directions!
• DOOR and window screens should be in good working condition. This will prevent mosquitoes from entering your home.
• DISTRICT personnel are available to address any mosquito problem you may be experiencing by calling 1-800-429-1022.