Vaccination is the administration of a vaccine to help the immune system develop immunity from a disease. Vaccines contain a microorganism or virus in a weakened, live or killed state, or proteins or toxins from the organism. In stimulating the body's adaptive immunity, they help prevent sickness from an infectious disease. When a sufficiently large percentage of a population has been vaccinated, herd immunity results. Herd immunity protects those who may be immunocompromised and cannot get a vaccine because even a weakened version would harm them. The effectiveness of vaccination has been widely studied and verified. Vaccination is the most effective method of preventing infectious diseases; widespread immunity due to vaccination is largely responsible for the worldwide eradication of smallpox and the elimination of diseases such as polio and tetanus from much of the world. However, some diseases, such as measles outbreaks in America, have seen rising cases due to relatively low vaccination rates in the 2010s – attributed, in part, to vaccine hesitancy. According to the World Health Organization, vaccination prevents 3.5–5 million deaths per year.
Measles is a highly contagious, vaccine-preventable infectious disease caused by measles virus. Symptoms usually develop 10–12 days after exposure to an infected person and last 7–10 days. Initial symptoms typically include fever, often greater than 40 °C (104 °F), cough, runny nose, and inflamed eyes. Small white spots known as Koplik's spots may form inside the mouth two or three days after the start of symptoms. A red, flat rash which usually starts on the face and then spreads to the rest of the body typically begins three to five days after the start of symptoms. Common complications include diarrhea, middle ear infection (7%), and pneumonia (6%). These occur in part due to measles-induced immunosuppression. Less commonly seizures, blindness, or inflammation of the brain may occur. Other names include morbilli, rubeola, red measles, and English measles. Both rubella, also known as German measles, and roseola are different diseases caused by unrelated viruses.
Rubella, also known as German measles or three-day measles, is an infection caused by the rubella virus. This disease is often mild, with half of people not realizing that they are infected. A rash may start around two weeks after exposure and last for three days. It usually starts on the face and spreads to the rest of the body. The rash is sometimes itchy and is not as bright as that of measles. Swollen lymph nodes are common and may last a few weeks. A fever, sore throat, and fatigue may also occur. Joint pain is common in adults. Complications may include bleeding problems, testicular swelling, encephalitis, and inflammation of nerves. Infection during early pregnancy may result in a miscarriage or a child born with congenital rubella syndrome (CRS). Symptoms of CRS manifest as problems with the eyes such as cataracts, deafness, as well as affecting the heart and brain. Problems are rare after the 20th week of pregnancy.
Vaccine hesitancy is a delay in acceptance, or refusal, of vaccines despite the availability of vaccine services and supporting evidence. The term covers refusals to vaccinate, delaying vaccines, accepting vaccines but remaining uncertain about their use, or using certain vaccines but not others. The scientific consensus that vaccines are generally safe and effective is overwhelming. Vaccine hesitancy often results in disease outbreaks and deaths from vaccine-preventable diseases. Therefore, the World Health Organization characterizes vaccine hesitancy as one of the top ten global health threats.
The MMRV vaccine combines the attenuated virus MMR vaccine with the addition of the chickenpox vaccine or varicella vaccine. The MMRV vaccine is typically given to children between one and two years of age.
Operation MECACAR is a multi-national immunization program launched in 1995 by the World Health Organization to coordinate polio vaccination efforts. The name of the operation was derived from the names of the regions participating in the operation: Eastern Mediterranean, Caucasus, Central Asian Republics and Russia. Currently, 18 countries are participating and more than 60 million children have been vaccinated.
Ciro Carlos Araujo de Quadros was a Brazilian leader in the field of Public Health, in particular, the area of vaccines and preventable diseases. He was born in Rio Pardo, Brazil.
A vaccination policy is a health policy adopted in order to prevent the spread of infectious disease. These policies are generally put into place by State or local governments, but may also be set by private facilities, such as workplaces or schools. Many policies have been developed and implemented since vaccines were first made widely available.
The eradication of infectious diseases is the reduction of an infectious disease's prevalence in the global host population to zero.
Measles & Rubella Initiative (MRI), launched in 2001, is a long-term commitment and partnership among leaders in public health and supports the goal of reducing measles deaths globally by 90% by 2010 compared to 2000 estimates.
The Expanded Program on Immunization is a World Health Organization program with the goal to make vaccines available to all children.
Vaccinate Your Family (VYF), formerly known as Every Child By Two (ECBT), is a non-profit organization, based in the United States, which advocates for vaccinations. Founded in 1991, its stated goals are to "raise awareness of the critical need for timely immunizations and to foster a systematic way to immunize all of America's children by age two." ECBT was founded by former First Lady of the United States Rosalynn Carter and former First Lady of Arkansas Betty Bumpers. ECBT was renamed to Vaccinate Your Family in 2018.
Measles vaccine protects against becoming infected with measles. Nearly all of those who do not develop immunity after a single dose develop it after a second dose. When rate of vaccination within a population is greater than 92%, outbreaks of measles typically no longer occur; however, they may occur again if the rate of vaccination decrease. The vaccine's effectiveness lasts many years. It is unclear if it becomes less effective over time. The vaccine may also protect against measles if given within a couple of days after exposure to measles.
Rubella vaccine is a vaccine used to prevent rubella. Effectiveness begins about two weeks after a single dose and around 95% of people become immune. Countries with high rates of immunization no longer see cases of rubella or congenital rubella syndrome. When there is a low level of childhood immunization in a population it is possible for rates of congenital rubella to increase as more women make it to child-bearing age without either vaccination or exposure to the disease. Therefore, it is important for more than 80% of people to be vaccinated. By introducing rubella containing vaccines, rubella has been eradicated in 81 nations, as of mid-2020.
European Immunization Week (EIW) is an annual regional initiative, coordinated by the World Health Organization Regional Office for Europe (WHO/Europe), to promote immunization against vaccine-preventable diseases since its launch in 2008. EIW activities are carried out by participating WHO/Europe member states. In the past these have included: disseminating informational materials about immunization, organizing immunization campaigns, organizing training sessions for health care workers, arranging workshops or conferences with political decision makers to discuss immunization, and holding press conferences about immunization-related issues.
Pakistan is one of the two remaining countries in the world where poliomyelitis (polio) is still categorized as an endemic viral infection, the other one being Afghanistan. As of the March 2023, there has been 1 documented case in Pakistan. There were 20 documented cases in Pakistan in 2022, 1 in 2021, and 84 in 2020. The total count of wild poliovirus cases in Pakistan in 2019 was 147.
World Immunization Week is a global public health campaign to raise awareness and increase rates of immunization against vaccine-preventable diseases around the world. It takes place each year during the last week of April.
Measles is extremely contagious, but surviving the infection results in lifelong immunity, so its continued circulation in a community depends on the generation of susceptible hosts by birth of children. In communities which generate insufficient new hosts the disease will die out. This concept was first recognized by Bartlett in 1957, who referred to the minimum number supporting measles as the critical community size (CCS). Analysis of outbreaks in island communities suggested that the CCS for measles is c. 250,000. Due to the development of vaccination against measles, the world has seen a 99% decrease in measles related cases compared cases before the vaccine was developed.
Vaccination policy of the United States is the subset of U.S. federal health policy that deals with immunization against infectious disease. It is decided at various levels of the government, including the individual states. This policy has been developed over the approximately two centuries since the invention of vaccination with the purpose of eradicating disease from the U.S. population, or creating a herd immunity. Policies intended to encourage vaccination impact numerous areas of law, including regulation of vaccine safety, funding of vaccination programs, vaccine mandates, adverse event reporting requirements, and compensation for injuries asserted to be associated with vaccination.
COVID-19 vaccination in Mexico is an ongoing immunization campaign against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the virus that causes coronavirus disease 2019 (COVID-19), in response to the ongoing pandemic in the country.
