Communicable Disease Prevention / Public Health Nursing

Public Health Nurses (PHNs) are committed to the well-being of communities and seek to promote health, prevent illness and achieve optimum health for the residents in City of Pasadena.  Our PHNs work with individuals, families, and other groups in the home and throughout the community.The public health nurse is a Registered Nurse with a Bachelor of Science Degree in Nursing (BSN), along with a Public Health Nurse Certificate issued by the State of California.

The PHN services include:

  • Education related to a communicable disease or illness
  • Illness prevention through health teaching
  • Assessment to identify family health needs
  • Case management
  • Patient advocacy
  • Community referrals
  • Community education/presentations

In addition, our Public Health Nurses work in partnership with our epidemiologist, and our health officer to control and prevent the occurrence and spread of communicable diseases.  We conduct epidemiological investigations of selected mandated reportable and communicable diseases including tuberculosis (TB), salmonellosis, pertussis, hepatitis, and meningitis.  Educational information and materials on the disease process, transmission, and prevention are available to the community.

Public Health Nursing Contact

Public Health Nursing
1845 N. Fair Oaks Ave.
Pasadena, CA 91103
Map & Directions >>>
Phone: (626) 744-6089

Mosquito-Borne Diseases

Dengue virus

Dengue viruses are spread to people through the bite of an infected Aedes species mosquito. In the U.S., dengue cases are typically only seen in individuals who have recently traveled outside of the country, such as parts of South America, Asia, and Africa. Rare cases of locally-acquired dengue have been reported.

Symptoms of dengue can be mild or severe and include fever, nausea, vomiting, rash, and body aches. Symptoms typically last two to seven days and although severe and even life-threatening illness can occur, most people recover after about one week.

Dengue outbreaks occur in many countries around the world. According to the Centers for Disease Control and Prevention (CDC), nearly half of the world’s population lives in areas with a risk of dengue.  Anyone who lives in or travels to an area with risk of dengue is at risk for infection. If you plan to travel outside of the U.S., find country-specific travel information to help you plan ahead.

Dengue outbreaks rarely occur in the continental United States. Because the types of mosquitoes that spread dengue are common throughout many areas of the country, local spread of dengue is possible. Most outbreaks in the continental U.S. have been relatively small and limited.

Dengue vaccine is not currently recommended for people living in the continental U.S. Rest, fluids, and over-the-counter medications are recommended to relieve symptoms and promote recovery.

See below for more information:

West Nile Virus (WNV)

West Nile virus (WNV) is the leading cause of mosquito-borne disease in the continental United States. It is most commonly spread to people by the bite of an infected mosquito.

Most people who are infected will not show symptoms, but some may experience headache, body aches, joint pains, vomiting, diarrhea, or rash. Symptoms of severe illness include high fever, headache, neck stiffness, stupor, disorientation, coma, tremors, convulsions, muscle weakness, vision loss, numbness, and paralysis. Adults over ages 60+ and people with certain medical conditions are more likely to develop serious illness.

There is currently no vaccine to prevent WNV. Rest, fluids, and over-the-counter medications are recommended to relieve symptoms and promote recovery. In severe cases, patients may need to be hospitalized to receive supportive treatment. If you think you or a family member might have WNV disease, contact a health care provider immediately. A health care provider may order laboratory tests to confirm WNV infection or other infections that can cause similar symptoms.

See below for information:

Zika virus

Zika virus is spread to people through the bite of an infected Aedes species mosquito. Zika can be spread from person to person through sexual contact or from a pregnant mother to their fetus.

There is no vaccine or specific treatment for Zika virus. Rest, fluids, and over-the-counter medications are recommended to relieve symptoms and promote recovery. If you think you or a family member might have Zika virus disease, contact a health care provider. Actions to protect yourself and others from infection include preventing mosquito bites and planning ahead before traveling outside of the country.

Prior to 2014, very few travel-associated cases of Zika virus disease were identified in the United States. In 2015 and 2016, large outbreaks of Zika virus in other countries led to an increase in travel-related cases and limited local transmission in the continental U.S. In 2017, the number of reported Zika virus cases in the United States started to decline. No local mosquito-borne Zika virus transmission has been reported in the continental U.S since 2018.

See below for more information:

Other mosquito-borne diseases

CDC – Other mosquito-borne diseases


Only a small number of mosquitoes are infected at any given time, so being bitten by a mosquito does not mean that you will get sick. However, preventing mosquito bites will reduce your risk of mosquito-borne illness.

Follow the tips below to prevent mosquito bites:

  • Wear insect repellent containing CDC and EPA approved active ingredients: DEET®, Picaridin, IR3535, or Oil of Lemon Eucalyptus.
  • Wear loosely fitted, light-colored, long-sleeved shirts and long pants.

Reducing mosquito populations decreases the chances of mosquito-borne diseases being transmitted to other people. Mosquitos only need small amounts of stagnant water to breed, which can result in mosquito breeding sites quickly appearing around your home and yard. Follow the tips below to eliminate breeding sites and reduce mosquito populations on your property:

  • Eliminate standing water in clogged rain gutters, rain barrels, discarded tires, buckets, watering troughs, or anything that holds water for more than a week.
  • Ensure that swimming pools, spas, and ponds are properly maintained.
  • Change the water in pet dishes, birdbaths, and other small containers weekly.
  • Report neglected swimming pools in your neighborhood to your vector control district.

Pasadena is a member of the San Gabriel Valley Mosquito and Vector Control District. For more information visit

Respiratory Illnesses

Respiratory illnesses like respiratory syncytial virus (RSV), influenza (flu), and COVID-19 are more common during the fall and winter seasons due to the colder months. Respiratory illnesses are contagious, and an infected person can spread the illness to others through sneezing, coughing, or direct contact. You can help reduce the spread of respiratory illnesses by staying up to date on vaccines, staying home when sick, wearing a well-fitting face mask, washing your hands, and covering your cough or sneeze.

See more information below to identify symptoms, treatment, and vaccination resources for common respiratory illnesses.

Influenza (flu)

Influenza, or flu, is a contagious respiratory illness caused by influenza viruses and can cause mild to severe symptoms. Flu signs and symptoms can include:

  • Fever or chills
  • Cough
  • Sore throat
  • Runny or stuffy nose
  • Muscle or body aches
  • Headaches
  • Fatigue
  • Vomiting and diarrhea (more common in children)

Treating flu symptoms should involve rest and staying hydrated by drinking plenty of fluids. Flu antiviral drugs may be prescribed by a health care provider to individuals at high risk of serious flu complications.

Receiving a flu vaccine each fall can reduce your chances of getting the flu. Vaccines are available at local pharmacies and from your healthcare provider. The Pasadena Public Health Department offers free flu vaccines on Mondays and Wednesdays during the fall season at 1845 N. Fair Oaks Avenue. For more information or assistance, call (626) 744-6121.


COVID-19 is a contagious disease caused by a virus named SARS-CoV-2. Symptoms of COVID-19 may appear 2-14 days after exposure to the virus and ranges from mild symptoms to severe illness. Older adults and individuals with preexisting health conditions are at greater risk of severe complications. COVID-19 can present a wide range of symptoms including:

  • Fever or chills
  • New loss of taste or smell
  • Cough
  • Sore throat
  • Shortness of breath or difficulty breathing
  • Congestion or runny nose
  • Fatigue
  • Nausea or vomiting
  • Muscle or body aches
  • Diarrhea
  • Headache

If you experience symptoms of COVID-19, get tested as soon as possible. COVID-19 symptoms can be reduced with rest and medications that help alleviate symptoms. Antiviral medications are available from a health care provider for those who qualify. Contact your healthcare provider from more information.

Getting vaccinated is the most effective method to prevent COVID-19. A dose of the updated COVID-19 vaccine is recommended for everyone ages 6 months+. Pasadena Public Health Department (PPHD) is administering a limited supply of COVID-19 vaccines to:

  • Adults ages 19+ who are uninsured or underinsured [through the Bridge Access Program (BAP)]
  • Children between ages 6 months and 18 years who are uninsured, underinsured, or enrolled in Medi-Cal [through the Vaccines for Children (VFC) Program]

For those who are eligible for BAP or VFC, walk-ins are welcomed every Monday and Wednesday between the hours of 8:30 a.m. – 4:30 p.m. (closed for lunch 11:30 a.m. – 1:30 p.m.) For questions regarding vaccine eligibility and available vaccines, contact PPHD’s immunization clinic at (626) 744-6121.

For those who are insured and are NOT eligible for BAP or VFC, please contact a health care provider or local pharmacy. For other partners and locations offering COVID-19 vaccines, visit

Respiratory Syncytial Virus (RSV)

Respiratory syncytial virus, or RSV, is a common respiratory illness that usually causes mild, cold-like symptoms but can cause serious complications. People infected with RSV usually show symptoms within 4-6 days after exposure. Symptoms can include:

  • Runny nose
  • Decreased appetite
  • Coughing and sneezing
  • Fever
  • Wheezing

RSV can cause serious infections such as bronchiolitis and pneumonia in infants and older adults with chronic medical conditions. Antiviral medications are not routinely recommended, but symptoms may be relieved with over-the-counter medications and by staying hydrated by drinking plenty of fluids.

RSV immunizations are now available for those who qualify. The Centers for Disease Control and Prevention (CDC) recommends RSV immunizations for adults ages 60+, infants and young children, and pregnant people. Refer to the CDC website or contact a health care provider to confirm eligibility and for more information.