American entertainer Olivia Rodrigo
Credit: © Tinseltown, Shutterstock

In the past year, American actress, singer, and songwriter Olivia Rodrigo has transformed from a Disney Channel star to a big name in pop music. Rodrigo first became known as an actress on television programs produced for the Disney Channel.

Olivia Isabel Rodrigo was born on Feb. 20, 2003, in Temecula, California, southeast of Los Angeles. Rodrigo began taking voice, piano, and guitar lessons as a child. She acted in middle and high school performances and began acting professionally in 2016. She played a leading character, Paige Olvera, on the Disney TV series “Bizaardvark” (2016-2019).

In 2019, Rodrigo gained the lead role of Nini in “High School Musical: The Musical—The Series.” She wrote and performed original songs for the series, including “All I Want” (2019) and a duet with Joshua Bassett, “Just for a Moment” (2020).

She released her first single “Drivers License” on Jan. 8, 2021. It soon hit number one on the Billboard Hot 100. The song is now nominated at the 64th Grammy Awards for song of the year, record of the year, and best pop solo performance. Rodrigo is also nominated for best music video or film for “Good 4 U” (2021), best pop vocal album for Sour (2021), album of the year for Sour, and best new artist.

After “Drivers License,” her next two singles— “Deja Vu” (2021) and “Good 4 U”—also debuted in the top 10 of the Billboard “Hot 100″ chart. She became the first recording artist to start a career with three singles in the top 10. Rodrigo’s debut album, Sour, included elements of pop, folk, and rock music.

Besides releasing catchy singles, Rodrigo also took a trip to the White House this summer. She met with President Joe Biden and the immunologist and Chief Medical Advisor to the President of the United States, Anthony Fauci, to discuss the importance of young people getting vaccinated against COVID-19. In December, Rodrigo was named Entertainer of the Year by Time magazine. She announced a world tour for 2022 in which she will travel to Europe, Canada, and across the United States.

Sandra Lindsay, left, an African American nurse, is injected with the COVID-19 vaccine developed by Pfizer on Dec. 14, 2020, in the Queens borough (section) of New York City. The rollout of the vaccine, the first to be given emergency authorization by the Food and Drug Administration, began the biggest vaccination effort in U.S. history.
Credit: © Mark Lennihan, Getty Images

On Monday, Aug. 23, 2021, the United States Food and Drug Administration (FDA) fully approved the two-dose Pfizer vaccine for COVID-19. The FDA has granted full approval of the vaccine for those aged 16 years and older. Full approval of a vaccine will make it easier for public and private organizations to require vaccinations. This includes hospitals, active-duty military, and schools.

The coronavirus disease COVID-19 has killed more than 4 million people and infected more than 200 million people around the world. The first countries with access to a vaccine began vaccinating their citizens in December 2020. Almost 5 billion doses of a vaccine preventing COVID-19 have been administered to people around the world.

In late November 2020, the companies Pfizer and Moderna each applied for emergency approval from the FDA for their COVID-19 vaccines. The two companies are among dozens of drugmakers that worked tirelessly to develop a vaccine against the deadly virus. Because the vaccine was authorized for emergency use after a clinical trial of 40,000 people, many citizens were hesitant to receive the vaccine. Full approval of the vaccine may assure some of those yet to get the shot of the vaccine’s safety.

Pfizer and Moderna began clinical trials in July. During these trials, participants were given either the vaccine or a placebo. A placebo is a substance that contains no active ingredient. Comparing infection rates in subjects who received the placebo with those among subjects who got the vaccine can help determine if the vaccine is effective. In the Pfizer and Moderna clinical trials, half the participants were given a placebo of saltwater, and half were given the vaccine. The researchers then waited to see who might get sick. The results were very promising—both vaccines were about 95 percent effective in preventing COVID-19. By contrast, commonly administered influenza vaccines (known as flu shots) are 40 percent to 60 percent effective.

A candlelit vigil on the National Mall in Washington, D.C., on Jan. 19, 2021, honored the hundreds of thousands of Americans killed by COVID-19.
Credit: © Chip Somodevilla, Getty Images

One year ago, on March 11, 2020, the World Health Organization declared the coronavirus disease COVID-19 a pandemic—that is, a disease that spreads over an extremely wide geographic area. In one year, the deadly respiratory disease has infected nearly 115 million people and killed more than 2.5 million people worldwide.

The first COVID-19 cases occurred in Wuhan, China, near a seafood and live animal market. This fact suggested to scientists that the disease may be zoonotic (spread from animals to people). Researchers proposed that, like the related diseases MERS (Middle East respiratory syndrome) and SARS (severe acute respiratory syndrome), COVID-19 may have its origin in bats. Further analysis of the virus SARS-CoV-2 showed that it had clearly originated in bats. SARS-CoV-2 stands for severe acute respiratory syndrome coronavirus 2. How the virus crossed over into human beings has not been determined. After the virus entered humans, human-to-human transmission became the chief way in which the disease spread.

As the pandemic progressed, some authorities closed schools and such nonessential businesses as restaurants, movie theaters, and hair salons. Some officials issued stay-at-home orders. The orders forbade people from leaving their homes except for such necessary activities as working at an essential job, buying food, or seeing a doctor.

To pass time over the long year and help stay cheerful while stuck at home, many people turned to baking treats, reading books, and making arts and crafts. For instance, some people recreated famous paintings. Such museums as the Getty Center in Los Angeles, California, provided people with prompts. Then, using household products and costumes buried at the bottom of toy chests, people recreated famous works of art. Emanuel Leutze’s “Washington Crossing the Delaware,” for example, became “Wagon Crossing the Street.” Re-enacting masterpieces was a great way to past the time, while you waited for your treats to bake.

Sandra Lindsay, left, a Black nurse, is injected with the COVID-19 vaccine developed by Pfizer on Dec. 14, 2020, in the Queens borough (section) of New York City. The rollout of the vaccine, the first to be given emergency authorization by the Food and Drug Administration, begins the biggest vaccination effort in U.S. history.
Credit: © Mark Lennihan, Getty Images

In December 2020, hope began to arrive in the form of vaccines. Vaccines are special medicines that can help make a person immune to a particular disease. The long-awaited “V-Day,” short for Vaccine Day, arrived in the United States on Monday, Dec. 14, 2020. Sandra Lindsay—a nurse at a hospital in the Queens borough (section) of New York City—was hailed as the first person in the United States to receive an authorized COVID-19 vaccination.

Not everyone who wants a vaccine has been able to get one right away. The first doses were given to healthcare workers. Then, frontline workers (workers likely to encounter the disease) followed, along with people vulnerable to the virus, including the elderly and those with such risk factors as obesity or diabetes.

Since December, nearly 10 percent of the U.S. population has received the vaccine. Tens of thousands more get vaccinated each day, raising hopes that the end of the pandemic is near.

Sandra Lindsay, a Black nurse, is injected with the COVID-19 vaccine developed by Pfizer on Dec. 14, 2020, in the Queens borough (section) of New York City. The rollout of the vaccine, the first to be given emergency authorization by the Food and Drug Administration, begins the largest vaccination effort in U.S. history.
Credit: © Mark Lennihan, Getty Images

The long-awaited V-Day, short for Vaccine Day, arrived in the United States on Monday, December 14, with the beginning of widespread vaccination against the coronavirus disease COVID-19. Vaccination involves the administration of special medicines called vaccines, which can help make a person immune to a particular disease. Sandra Lindsay—a nurse at a hospital in the Queens borough (section) of New York City—became the first person in the United States to receive the authorized COVID-19 vaccination. COVID-19 has killed more than 1 million people and infected more than 60 million people around the world. The United States Food and Drug Administration (FDA) granted an emergency use authorization for the vaccine, by the pharmaceutical company Pfizer, on December 11. V-Day provided a moment of hope against the COVID-19 pandemic (worldwide outbreak of disease) even as the U.S. death toll topped 300,000.

The fact that Lindsay—a Black health care worker—was first in line to receive the vaccine is significant. In the United States, COVID-19 has disproportionally affected Black Americans, and medical workers have been on the front line of the fight against the disease. Lindsay said it was important for her to take the vaccine, in part because of the history of unequal and racist treatment of minorities in the medical system. In particular, she mentioned the Tuskegee Syphilis Study, a notorious medical experiment involving Black Americans. Beginning in 1932, medical workers conducted blood tests among 4,000 Black men in Tuskegee, Alabama, and selected for the study about 400 who were found to be infected with the sexually transmitted disease syphilis. The participants in the study were not informed that they were infected with syphilis or told about the expected outcomes of the experiment. Lindsay hoped to inspire Black people and other minorities who may be skeptical about the vaccine. After receiving the first of two doses, she said, “It feels surreal. It is a huge sense of relief for me, and hope.”

The first doses of the Pfizer vaccine to be given to Americans were shipped on Sunday, December 13. The United States is not the first country to approve the vaccine. On December 8, Margaret Keenan of the United Kingdom became the first person in the world to receive the authorized vaccine. Canada has also approved the vaccine, administering its first dose the same day as the United States.

In many cases, administration of a COVID-19 vaccine will be voluntary. But, it will be a while until everybody who wants a vaccine can get one. In the United States, the first doses will be given to health care workers. Frontline workers (workers likely to encounter the disease) and people who are vulnerable to the virus, including the elderly and people with such risk factors as obesity or diabetes will be next. Some of these people may receive the vaccine by the end of 2020. But, most people will have to wait until the spring of 2021.

Most vaccines are administered into the body by injection. A vaccine contains substances that stimulate the body’s immune system to produce molecules called antibodies. The immune system uses antibodies to fight against germs that enter the body. Antibodies produced in response to a vaccine can protect a person who is exposed to the actual disease-causing organism. The process of protecting the body in this way is called immunization. Vaccines have been successful in fighting many other diseases, including chickenpox, meningitis, and yellow fever.

Pfizer and Moderna began clinical trials in July. During these trials, participants were given either the vaccine or a placebo. A placebo is a substance that contains no active ingredient. Comparing infection rates in subjects who received the placebo with those among subjects who got the vaccine can help determine if the vaccine is effective. In the Pfizer and Moderna clinical trials, half the participants were given a placebo of salt water, and half were given the vaccine. The researchers then waited to see who might get sick. The results were very promising—both vaccines were about 95 percent effective in preventing COVID-19. By contrast, commonly administered influenza vaccines (known as flu shots) are 40 percent to 60 percent effective.

In late November, the companies Pfizer and Moderna each applied for emergency approval from the FDA for their COVID-19 vaccines.  The two companies are among dozens of drugmakers that have worked tirelessly to develop a vaccine against the deadly virus.

Nurse administering a vaccination.
Credit: © Shutterstock

The coronavirus disease COVID-19 has killed more than 1 million people and infected more than 60 million people around the world. But, hope may be just around the corner, in the form of vaccines. Vaccines are special medicines that can help make a person immune to a particular disease. Vaccines have been successful in fighting many other diseases, including chickenpox, meningitis, and yellow fever.

In late November, the companies Pfizer and Moderna each applied for emergency approval from the United States Food and Drug Administration (FDA) for their COVID-19 vaccines.  The two companies are among dozens of drugmakers that have worked tirelessly to develop a vaccine against the deadly virus.

Most vaccines are administered into the body by injection. A vaccine contains substances that stimulate the body’s immune system to produce molecules called antibodies. The immune system uses antibodies to fight against germs that enter the body. Antibodies produced in response to a vaccine can protect a person who is exposed to the actual disease-causing organism. The process of protecting the body in this way is called immunization. 

Pfizer and Moderna began clinical trials in July. During these trials, participants were given either the vaccine or a placebo. A placebo is a substance that contains no active ingredient. Comparing infection rates in subjects who received the placebo with those among subjects who got the vaccine can help determine if the vaccine is effective. In the Pfizer and Moderna clinical trials, half the participants were given a placebo of salt water, and half were given the vaccine. The researchers then waited to see who might get sick. The results were very promising—both vaccines were about 95 percent effective in preventing COVID-19. By contrast, commonly administered influenza vaccines (known as flu shots) are 40 percent to 60 percent effective.

Vaccines are one of the most powerful tools in modern medicine. They have nearly or completely eliminated several diseases. For instance, Edward Jenner, a British physician, introduced vaccination in 1796 as a preventive measure against smallpox. By the late 1970′s, smallpox vaccination had wiped out the dreadful disease. In the United States and many other countries, disease has been greatly reduced by widespread childhood immunizations. In 1952, for example, more than 21,000 cases of the paralytic disease polio were reported in the United States. By the end of the 1900′s, fewer than 10 cases per year were reported. More than 95 percent of children in the United States receive all their recommended immunizations by the time they enter school.

In many cases, administration of a COVID-19 vaccine will be voluntary. But, it will be a while until everybody who wants a vaccine can get one. Once approved, the vaccine—from Pfizer, Moderna, or other companies—will likely first be available to health care workers, frontline workers (workers likely to encounter the disease), and people who are vulnerable to the virus, including the elderly and people with such risk factors as obesity or diabetes. Some of these people may receive the vaccine by the end of 2020. But, most people will have to wait until the spring of 2021.

May 8, 2019

Measles is making a comeback. The highly contagious disease is characterized by the spotty pink rash it causes over the body. Once rare, measles has come roaring back in the United States, as more than 750 cases were officially recorded in the first four months of 2019. That number is more than twice the amount of U.S. cases typically recorded in a full year. The new measles cases were primarily recorded in large outbreaks in the states of New York and Washington, but the disease has also appeared in 21 other states.

A health worker gives a measles vaccine to a young girl in Peshawar, Pakistan. Credit: © Asianet-Pakistan/Shutterstock

Measles chiefly strikes young children, but it is increasingly affecting adolescents and young adults. People who have the disease pass the virus by coughing and sneezing. People can spread the disease long before they realize they are ill. Three to five days after the first symptoms appear, faint pink spots break out over the body. Few people in the United States die of measles. But the disease is dangerous to those with a weakened immune system, and measles kills many undernourished children in other countries.

A child with measles shows the characteristic pink rash that spreads over the body. Credit: © Lowell Georgia, Photo Researchers

Public health experts are dismayed that measles has regained a foothold in the United States, where it was once eradicated. In 2000, the U.S. Centers for Disease Control and Prevention (CDC) announced that measles had been completely eliminated. This was an important public health achievement made possible by the widespread use of the highly effective measles vaccine. Of course, that did not mean that measles was completely gone. CDC officials still recorded a number of cases brought in from travelers—mostly from parts of Asia and Europe where measles is less well controlled. But, until recently, measles transmission in the United States had ended.

In recent years, however, a misinformed yet highly visible anti-vaccination (anti-vaxx for short) movement has led to fewer vaccinations, which has in turn led to the current measles outbreak. Anti-vaxx activists in the United States have launched a coordinated effort to convince parents not to vaccinate their children. They falsely claim that childhood vaccinations can cause a variety of health complications, autism, or even death. This disinformation is spread through websites, Facebook, and other social media. Medical professionals point out that anti-vaxx claims are often misleading and lack any credible or relevant evidence.

The anti-vaxx movement has spearheaded efforts to allow parents to opt out of mandatory vaccinations previously require to enroll their children in public schools. The latest measles outbreak is spread primarily though such unvaccinated students, who expose other children to measles and other preventable diseases, such as whooping cough.

Unvaccinated people, including those who may have a weakened immune system from chemotherapy, can be protected from measles through herd immunity. This term describes a population protected from a disease because high rates of vaccination make it impossible for the virus to spread. Although the measles virus can remain infectious for two or more hours outside the human body, the virus ultimately requires a human host to reproduce. If enough people in a population are vaccinated, the cycle of transmission is disrupted, and the virus will become extinct.

However, herd immunity does not work unless a great majority of the population is vaccinated. To achieve herd immunity for measles, at least 90 to 95 percent of the population needs to be vaccinated. In the past, this was achieved through mandatory vaccinations for school children. In recent years, however, increasing numbers of parents have requested vaccine exemptions for their children on ethical or religious grounds. Many states, cities, and school districts are now reconsidering allowing such exemptions.

December 5, 2014

Officials at the United States Centers for Disease Control and Prevention (CDC) are finding that vaccines administered this year to protect people from influenza (the flu) are not as effective as they had hoped. But, they stressed, people should not use this as an excuse to skip this year’s flu shot. In addition to feeling miserable, people with the flu may develop flu-related complications that may lead to hospitalization and death, health officials said. Children and the elderly are especially at risk.

Global flu outbreaks occur each year, usually in winter months. Each outbreak is caused by viruses slightly different from those associated with earlier outbreaks. The differences are caused by mutations that occur in the viruses. A mutation is a change in the hereditary material of an organism. Mutations in a flu virus may cause an unexpected flu strain to become more common in a given year. That seems to be the case in 2014. This strain was associated with severe outbreaks, including higher-than-normal numbers of hospitalizations and deaths, during the 2003-2004, 2007-2008, and 2012-2013 flu seasons.

Influenza viruses may cause flu when they are inhaled. The viruses shown here are greatly magnified and artificially colored. (© Linda Stannard, UCT/SPL from Photo Researchers)

Vaccine manufacturers must produce flu vaccine months before any outbreak in order to ensure sufficient vaccine supplies when flu season hits. But the vaccine must closely match the strains (types) in each year’s outbreak. The decision on what strains should be used in a year’s vaccine is based on the common strains found worldwide by global health agencies in the past year. However, CDC scientists found that fewer than half of the flu virus samples obtained from patients from October and November 2014 matched any of the strains used to make this year’s vaccines. Scientists often name the different flu strains after the place where the strain was first identified. This year’s flu vaccines were made to match several flu strains, including one called A/Texas/50/2012. But in samples from flu patients taken in October and November, only 48 percent matched this flu strain. Most of the other virus samples were from a strain called A/Switzerland/9715293. This strain was not used to make flu vaccine in 2014. As a result, the flu vaccine currently used is not as effective at protecting people from this strain.

Nevertheless, medical experts note that even if a vaccine does not exactly match the most common strains of flu circulating, the vaccine still provides significant protection. People who have had a flu shot may still get sick this year. However, they will typically experience a less severe illness than they would have without the shot. CDC officials stressed that over the years, hundreds of millions of Americans have safely received flu vaccines. The most common side effects are soreness, redness, tenderness or swelling where the flu shot was given and nasal congestion after the flu vaccine nasal spray.

Additional World Book articles:

• Epidemic
• Spanish flu
• Influenza: A New Threat from an Old Foe (a Special Report)
• Handwashing: The First Line of Defense Against Disease (a Special Report)

Information about flu and flu vaccines can be found on the Influenza page of the CDC website.

May 24, 2012

A group dedicated to eradicating polio worldwide launched an emergency plan after recent outbreaks of the disease threatened countries that previously had been free of polio. The group, known as the Global Polio Eradication Initiative (GPEI), headquartered in Geneva, Switzerland, was launched by the World Health Organization (WHO), national governments, the U.S. Centers for Disease Control and Prevention, the United Nations Children’s Fund (UNICEF), and Rotary International in 1988.

Polio, officially known as poliomyelitis, is an infection caused by a virus. Some people may have only such mild, short-term symptoms as headache, sore throat, and vomiting. Others may develop back and leg pain that leads to permanent paralysis.

In the past, polio epidemics were common throughout the world and greatly feared. However, during the 1950′s, American researcher Jonas E. Salk developed the first vaccine against polio. In 1961, an oral vaccine developed by another American researcher, Albert B. Sabin, was approved. The vaccines quickly became part of the standard vaccination regimen recommended for children. Since then, polio has been nearly eliminated in developed countries. From 1955 to 1957 in the United States, inoculation reduced the incidence of polio by 85 to 90 percent. When GPEI was founded in 1988, more than 350,000 children in more than 125 countries were paralyzed from polio each year. By the first decade of the 2000′s, the incidence of polio had been reduced by 99 percent.

Dr. Salk administers the polio vaccine to a child in 1954 as part of a mass testing program. (Courtesy of March of Dimes Foundation)

In early 2012, health officials at WHO were thrilled to announce that India (the second most populous country in the world) had been free of polio for one year. Nevertheless, polio remains endemic (constantly present somewhere in the population) in Afghanistan, Pakistan, and Nigeria. In addition, China, Tajikistan, and West Africa reported large outbreaks of polio in 2012, their first cases in many years. Epidemiologists (doctors who study epidemics) determined that the disease had spread into China from Pakistan and into West Africa from Nigeria.

An infant in Afghanistan is immunized against polio through a program administered by UNICEF. (Courtesy of AP/Wide World)

GPEI officials urged donor countries to step up funding so that the group could intensify its efforts to increase vaccination coverage in Afghanistan, Pakistan, and Nigeria. The group hoped that more technical assistance and greater social mobilization would increase accountability, coordination, and oversight of each country’s vaccination campaign and ease cultural misconceptions that often interfere with immunization.

Additional World Book articles

• Iron lung
• March of Dimes Foundation
• Roosevelt, Franklin Delano
• Fighting a Persistent Foe (a special report)
• Medicine 1955 (Back in Time article)
• Medicine 1959 (Back in Time article)
• Medicine 1960 (Back in Time article)
• Medicine 1961 (Back in Time article)
• Medicine 1963 (Back in Time article)
• Nobel Prizes 1954 (Back in Time article)

Jan. 31, 2012

India celebrated a major victory against polio in January with the announcement that for the first time, the country had not recorded any new cases of the crippling disease during the previous 12 months. In 2009, at least 741 cases of infection with wild (naturally occurring) poliovirus were recorded in India, more than in any other country. In 2011, several million government and foreign aid workers fanned out across India in two national immunization campaigns aimed at reaching some 172 million children under the age of 5. About 70 million children in the highest-risk areas received multiple vaccinations. Officials from the World Health Organization (WHO) said India’s $2-billion campaign to eradicate the disease was “arguably its greatest public health achievement.”

Polio is caused by a virus that enters the mouth and nose, then travels to the nervous system through the intestines. Crowded living conditions and poor sanitary conditions make it easier for the virus to spread. The virus may attack the nerve cells of the brain and spinal cord, causing paralysis. However, infection by poliovirus does not always result in severe illness. Some patients show only mild symptoms, such as fever, headache, sore throat, and vomiting. Some polio patients suffer new symptoms 30 years or more after the initial attack, a complication called post-polio syndrome.

The first effective weapon in preventing poliomyelitis was a vaccine developed by Jonas Salk in the early 1950′s. Albert B. Sabin later developed an effective oral polio vaccine.

UNICEF promotes the health and well-being of young people throughout the world. This infant is receiving a polio vaccination as part of a UNICEF immunization program in Afghanistan. AP/Wide World

India’s efforts to eradicate the disease were supported by the Global Polio Eradication Initiative, launched in 1988 by WHO, Rotary International, and the United Nations Children’s Fund. By 2007, the Initiative’s efforts had slashed worldwide polio cases by 99 percent. In 2012, wild poliovirus was endemic (constantly present somewhere in the population) in only three countries–Afghanistan, Nigeria, and Pakistan, though polio outbreaks sometimes occurred in other countries. No cases of polio have been recorded in the United States since 1984. Public health officials hope to make polio the second infectious disease eradicated worldwide. In 1980, officials from WHO formally announced that smallpox, one of most feared diseases in history, had been eliminated worldwide.

Additional World Book articles:

• Fighting a Persistent Foe (A Special Report)
• Kenny, Elizabeth
• Perlman, Itzhak
• Roosevelt, Franklin Delano (Battle with polio)