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Vaccine-Preventable Diseases

Chickenpox (Varicella Virus)

Chickenpox is typically mild and self-limiting but may cause very serious complications. Dangerous bacterial infections of chickenpox skin lesions and pneumonia are the most common causes of hospitalization. Chickenpox can be a very serious disease for young children less than one year of age and adults older than 15 years. Adults account for only five percent of cases but account for approximately 35 percent of deaths.


Tetanus is an acute disease caused by Clostridium tetani. Tetanus commonly causes muscle stiffness, uncontrolled muscle contractions, and spasms. Eleven percent of tetanus cases die.


Diphtheria is caused by the bacterium Corynebacterium diphtheriae. Complications include heart abnormalities, paralysis of the eye muscles and limbs, difficulty breathing, and ear infections. Death occurs in five to 10 percent of all cases. The death rate of those younger than five years or older than 40 years of age climbs to 20 percent.

Whooping cough

Whooping cough, or pertussis, is a highly contagious bacterial infection. The first symptoms are similar to those of a common cold: a runny nose, sneezing, low-grade fever, and a mild, occasional cough. The symptoms may progress to severe coughing fits, particularly at night, with “whooping” (primarily in children), and vomiting after coughing. The cough associated with pertussis usually lasts several weeks. Pertussis is very serious in young children, with pneumonia being the most common complication. Adults and adolescents usually have milder symptoms without the characteristic “whoop,” but are important in the epidemiology of the disease since they often spread the disease to others.

Early childhood pertussis vaccines provide protection when children are most susceptible to serious illness. Every child should receive doses of the pertussis vaccine at 2, 4, 6, and 15 months and then a booster at 4-6 years of age.

Additionally, adults and adolescents should be vaccinated to protect themselves and their loved ones from pertussis. In 2005, two new vaccines became available for the prevention of pertussis in adolescents and adults: Boostrix® (for ages 10 and older) and Adacel™ (for ages 11 and older). Contact your regular healthcare provider for more information.

Read the Vaccine Information Statements for:

Haemophilus influenzae type b (Hib)

Haemophilus influenzae type b (Hib) bacterial infections were the leading cause of bacterial meningitis in children under five years of age before the introduction of effective vaccines. Throat inflammation (redness and swelling), arthritis (joint swelling), and skin infections are also common complications of Hib infections.

Hepatitis A

Hepatitis A is a serious liver disease. It is usually spread through close, personal contact with an infected person or when a person unknowingly ingests the virus from objects, food, or drinks that are contaminated by small amounts of stool (poop) from an infected person.

Most adults with hepatitis A have symptoms, including fatigue, low appetite, stomach pain, nausea, and jaundice (yellow skin or eyes, dark urine, and light-colored bowel movements). Most children less than six years of age do not have symptoms.

A person infected with hepatitis A can transmit the disease to other people even if he or she does not have any symptoms of the disease.

Read the Vaccine Information Statements for Hepatitis A vaccinations

Hepatitis B

Hepatitis B is a virus that spreads through blood and most body fluids, which infects the liver. Individuals infected with Hep B can develop fulminant (an unusually severe or aggressive form of the disease) hepatitis, which can lead to death. Hep B infection can become chronic (long-term infection). Chronic hepatitis B can lead to serious complications, including liver scarring, liver failure, and liver cancer. In the United States, an estimated 1,000 to 1,500 people die from Hep B- related liver cancer each year. Ninety percent of babies infected with Hep B at birth become chronic carriers, greatly increasing their risk of liver-related problems.

HPV (Human Papillomavirus)

HPV (human papillomavirus) vaccine can prevent infection with some types of human papillomavirus.

HPV infections can cause certain types of cancers, including:

  • cervical, vaginal, and vulvar cancers in women
  • penile cancer in men
  • anal cancers in both men and women
  • cancers of the tonsils, base of the tongue, and back of the throat (oropharyngeal cancer) in both men and women

HPV vaccine can prevent over 90% of cancers caused by HPV.

Read the Vaccine Information Statement for HPV (Human Papillomavirus)


Influenza, commonly called “the flu,” is a highly contagious respiratory illness caused by influenza viruses. The flu may result in mild illness or severe illness accompanied by life-threatening complications. On average, 114,000 people are hospitalized for flu-related complications, and 36,000 Americans die each year from complications of the flu. Signs and symptoms of flu include fever, headache, extreme tiredness, dry cough, sore throat, runny or stuffy nose, and muscle aches. Gastrointestinal symptoms such as nausea, vomiting, and diarrhea are much more common among children than adults. The main way the flu is spread is from person to person in respiratory droplets of coughs and sneezes.

Meningococcal ACWY/Meningococcal B

Meningococcal disease can cause meningitis (infection of the lining of the brain and spinal cord) and infections of the blood. Even when it is treated, meningococcal disease kills 10 to 15 infected people out of 100. And of those who survive, about 10 to 20 out of every 100 will suffer disabilities such as hearing loss, brain damage, kidney damage, loss of limbs, nervous system problems, or severe scars from skin grafts. 

Anyone can get meningococcal disease. Certain people are at increased risk, including:

  • Infants younger than one-year-old
  • Adolescents and young adults 16 through 23 years old
  • People with certain medical conditions that affect the immune system
  • Microbiologists who routinely work with isolates of N. meningitidis, the bacteria that cause meningococcal disease
  • People at risk because of an outbreak in their community

Read the Vaccine Information Statements for Meningococcal ACWY

Read the Vaccine Information Statements for Meningococcal B


Approximately 30 percent of reported measles cases result in one or more of the following complications: inner ear infection, pneumonia, brain inflammation, seizures, and death. Children younger than five and adults older than 20 years of age are most likely to have complications due to measles infection.


Mumps is an infectious disease caused by a virus. The most common symptom of mumps is swelling of the salivary glands close to the jaw. Other symptoms include fever, headache, and earache.

More serious symptoms can occur in rare cases, including meningitis, swelling of the testes or ovaries, and inflammation of the joints.


Rubella virus can lead to arthritis (joint swelling), brain inflammation, and internal bleeding. The main objective of rubella vaccination is to prevent rubella syndrome in newborns. In newborns, rubella infection may damage all organs leading to congenital defects (deafness, eye defects, heart defects, and nerve abnormality) that may not show up for two to four years. Rubella may also lead to fetal death, spontaneous abortion, and premature delivery.

Pneumococcal Conjugate/ Pneumococcal Polysaccharide

Pneumococcal disease refers to any illness caused by pneumococcal bacteria. These bacteria can cause many types of illnesses, including pneumonia, which is an infection of the lungs.  Pneumococcal bacteria are one of the most common causes of pneumonia.

Besides pneumonia, pneumococcal bacteria can also cause:

  • Ear infections
  • Sinus infections
  • Meningitis (infection of the tissue covering the brain and spinal cord)
  • Bacteremia (infection of the blood)

Anyone can get pneumococcal disease, but children under 2 years old, people with certain medical conditions or other risk factors, and adults 65 years or older are at the highest risk.


Polio, or Poliomyelitis, is a virus that can lead to paralysis and death. The last outbreak of poliovirus in the United States occurred in 1979. Polio is still common in many places around the world. Due to international travel, polio vaccination remains important.

  • Learn more about polio.
  • Read the Vaccine Information Statements for polio vaccinations.


Rotavirus commonly causes severe, watery diarrhea, mostly in babies and young children. Vomiting and fever are also common in babies with rotavirus. Children may become dehydrated and need to be hospitalized, and can even die.

Read the Vaccine Information Statements for Rotavirus


Shingles (also called herpes zoster, or just zoster) is a painful skin rash, usually with blisters. In addition to the rash, shingles can cause fever, headache, chills, or upset stomach. Rarely, shingles can lead to complications such as pneumonia, hearing problems, blindness, brain inflammation (encephalitis), or death. The risk of shingles increases with age. 

Recombinant shingles vaccine is recommended for:

  • Adults 50 years and older
  • Adults 19 years and older who have a weakened immune system because of disease or treatments

Read the Vaccine Information Statements for Shingles