General Vaccine Information
Infectious diseases are spread from one person to another, usually through very small organisms called bacteria or viruses (“micro”-organisms). These microorganisms reproduce in their host, often making them sick, and then spread to the next unlucky person. The first time someone’s immune system meets a new bacteria or virus, it works very hard to create the best possible tools to destroy that particular microorganism. Generally, these tools are called antibodies and copies of them are kept stored away in the body so if the immune system ever sees that bacteria or virus again, it’s much easier to fight off. This is called gaining immunity, and it’s the reason a person who has already been sick with a particular disease usually won’t get sick from it again.
Vaccination, or immunization, offers us a way to create immunity and prevent serious illness without ever being exposed to the real microorganism. A vaccine contains pieces of bacteria or viruses, or whole but non-functional bacteria or viruses. A person can’t catch the disease from the vaccine, but their immune system doesn’t know that. It responds to the vaccine the same way it responds to a real threat, and it makes antibodies just like it would if it encountered the real bacteria or virus The important difference is that the person doesn’t get sick and can’t spread a disease to anyone else.
Are vaccines safe?
Yes! All vaccines have been rigorously tested for safety and effectiveness by doctors and scientists around the world. Read more about vaccine safety testing.
Will vaccines make me sick?
While a vaccine cannot make you sick with the bacteria or virus it contains, some people may experience some flu-like symptoms due to the immune response caused by the vaccine. These are typically mild and go away after a few days. Read more about specific vaccine side effects. Also, it takes the immune system a couple of weeks to create immunity after vaccination, and it is still possible to contract the disease during that time.
Who needs vaccines?
While infants and children are at the greatest risk from infectious diseases and, therefore, need them the most, people of all ages can benefit from the protection vaccines offer. See our Resources for Children, Adults and Pregnant Women page for more information.
Where do my family and I get vaccinated?
The best place to get immunized is at your doctor’s office so they can maintain your immunization history. If you have health insurance (such as Medi-Cal, Alameda Alliance, Kaiser, Blue Shield, Blue Cross, United Health Care, etc.), call your doctor’s office in advance about availability. They often have same-day appointments. At your doctor’s office, immunizations will be free because they will likely be covered by your insurance.
If you do not have a regular doctor’s office, immunizations are available at most pharmacy chains or local pharmacies. Call your nearest pharmacy to determine the cost and insurance coverage. There are limited free or low-cost immunization clinics within Alameda County. It is always a good idea to call in advance to ensure that the vaccine you are seeking is available. Back-to-school clinics usually take place right before the start of the school year so that children meet school requirements.
The Centers for Disease Control and Prevention (CDC) recommends that pregnant women receive the whooping cough vaccine for adolescents and adults (called Tdap vaccine) during the third trimester of each pregnancy. For more information about which pharmacies offer Tdap to pregnant women, please see Alameda County Pharmacy Directory.
How do I locate my vaccination records?
Immunization records are often needed for entry into childcare, kindergarten, school, summer camp, and college or other post-high school training, as well as for future employment and international travel. There is no national organization that maintains this information. If you need official copies of vaccination records, or if you need to update your personal records, there are several places you can look:
- All previous healthcare providers
- Your parents or other caregivers, if they have records
- Local immunization registry or public health department
For more ways to locate old immunization records please visit CDC or Immunize.org.