February 24, 2020

Last week, on February 19, the Wuhan coronavirus epidemic claimed its 2,000th victim. First recognized in human beings in the Chinese city of Wuhan in December 2019, the coronavirus has since spread steadily and touched nearly all parts of the world. Wuhan coronavirus is an informal name for a respiratory disease named Coronavirus Disease 2019 (COVID-19). Coronaviruses are one of many virus types that cause the common cold and other diseases of the upper respiratory system. The COVID-19 is a pneumonia-like disease. Its symptoms include breathing difficulties, coughing, and fever. It is a contagious disease, and the symptoms can be fatal in a small percentage of cases.

This illustration of Coronavirus Disease 2019 (COVID-19) shows the spikes on the outer surface of the virus that appear as a corona, giving the virus its name. Credit: Centers for Disease Control and Prevention (CDC)

On Jan. 30, 2020, when the disease had caused 170 deaths in some 8,000 confirmed cases, the World Health Organization (WHO) declared the virus outbreak to be a public health emergency of international concern. The WHO recommended urgent containment measures as the number of cases and deaths continued to climb. By mid-February, more than 40,000 cases of the virus had been confirmed. The disease was given the temporary name 2019-nCoV, for novel (new) coronavirus of 2019. It was later officially named COVID-19. The virus that causes the disease was named SARS-CoV-2.

January 13, 2020

Earth has been a particularly dangerous place in recent weeks. Airplane crashes, military clashes, terror attacks, and political unrest have taken a toll on human life and happiness lately, but it is a series of natural disasters that has caused the most trouble. A typhoon ravaged the Philippines, deadly flash floods hit Indonesia, bushfires continued to rage in Australia, a measles epidemic continued to kill in the Democratic Republic of the Congo, and a series of earthquakes rattled Puerto Rico.

Firefighters confront a bushfire near the Blue Mountains town of Bilpin, New South Wales, on Dec. 19, 2019. Credit: © 1234rf/Shutterstock

On Christmas Eve and Christmas Day Typhoon Phanfone (also called Ursula) struck the Philippines, producing high winds and flooding that killed 105 people in the Visayan Island provinces of Biliran, Capiz, Iloilo, and Leyte. Phanfone was a Category 2 storm (moderate strength) with sustained winds of more than 90 miles (150 kilometers) per hour. Storm surges and deadly flash floods hit communities just as families were gathering to celebrate the Christmas holiday. Thousands of homes were damaged or destroyed.

On New Year’s Day in Indonesia, abnormally heavy monsoon rains caused flash floods that killed 66 people and displaced hundreds of thousands of others in Jakarta, the capital. Some 14.5 inches (37 centimeters) of rain fell on New Year’s Eve, causing the Ciliwung and Cisadane rivers to overflow. Floodwaters submerged more than 150 neighborhoods and caused landslides in the Bogor and Depok districts on the outskirts of Jakarta. Flood water levels in some areas peaked at more than 13 feet (4 meters). Electric power was cut off, and closed schools and government buildings were converted into emergency shelters.

On January 7, the World Health Organization announced the 6,000th death from measles in the Democratic Republic of the Congo (DRC) since an epidemic began there in 2019. More than 300,000 suspected measles cases have been reported in the DRC—a nation also troubled by recent terror attacks. The epidemic has continued and grown because of low vaccination coverage, malnutrition, weak public health systems, outbreaks of other epidemic-prone diseases (such as Ebola), and the difficulty of getting health care to people in remote areas.

In Puerto Rico, after several smaller earthquakes, a 6.4-magnitude temblor struck the southwestern part of the island on January 7. The earthquake, the strongest to hit Puerto Rico in more than 100 years, killed one person, toppled hundreds of structures, and forced a state of emergency. Many people lost their homes, the island briefly lost electric power, and schools and public offices were closed. In the 10 days before the 6.4-magnitude earthquake, the United States Geological Survey recorded hundreds of temblors in Puerto Rico—including 10 of 4-magnitude or greater.

A number of major bushfires have lately devastated southeastern Australia. Since September, the wild fires—mostly in New South Wales, Queensland, and Victoria—have burned more than 25.5 million acres (10.3 million hectares), an area the size of South Korea. The bushfires have destroyed more than 2,100 homes and killed 27 people and hundreds of millions of animals. On January 8, the Australian government ordered the mass slaughter of thousands of wild camels and horses that have invaded rural towns looking for water. Many people are without electric power and telecommunications in Australia’s southeast, and some were without drinking water and other supplies. Smoke has obscured the city skies of Canberra, Melbourne, and Sydney. The bushfires followed a three-year drought that experts link to climate change.

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.

September 28, 2017

An opioid drug crisis has swept parts of the United States in 2017 as unprecedented numbers of people became addicted—and many died. An opioid is any synthetic or semi-synthetic drug that resembles an opiate (drug that contains opium) in its effects. People most often take opioids—which are legally available by prescription—for pain, but the drugs are highly addictive. The opioid crisis has devastated thousands of families and communities.

A pharmacist doles out a prescription of fentanyl, a powerful synthetic opioid that is sometimes combined with heroin. Fentanyl overdoses have killed thousands of people. Credit: Dennis Yip, Fentanyl Safety

Opioid overdose incidents have been widespread and often shocking. For example, a mother collapsed in the stands at a Little League Baseball game in Ohio; an Indiana couple was found unconscious in a running car with two young children in the backseat; and a child called 911 after finding her mother and three adults passed out from overdoses in Massachusetts.

Public health officials have called the current epidemic of opioid overdoses the worst drug crisis in American history. In 2015, the most recent year for which complete data are available, more than 50,000 people died from drug abuse and overdose. Opioids played a role in 33,000 of those deaths. For the first time, deaths from opiate overdose surpassed deaths from homicide with a gun, and overdose deaths were nearly equal to the number of deaths from car crashes. Data from the U.S. Centers for Disease Control and Prevention show the current opioid epidemic has claimed an average of 142 lives each day in 2017.

In the United States, opioid-related visits to hospital emergency rooms have doubled since 2005, and admissions have increased 64 percent. According to a report from the Agency for Healthcare Research and Quality, a unit of the U.S. Department of Health and Human Services, American hospitals experienced an average of 3,500 visits per day for opioid-related issues in 2014, compared with 1,800 per day in 2005. While emergency room visits rose for all age groups, the largest increase was seen in adults age 25 to 44. Men and women were equally likely to seek medical care for opioid-related issues over that time.

Although the epidemic is nationwide, certain areas have been harder hit than others. The Appalachian and nearby regions of Kentucky, Ohio, Pennsylvania, and West Virginia have seen the highest rate of opioid overdose deaths, and parts of New England and the Southwest are also far above the national average.

Opioids are any drugs made from or containing opium and other synthetic drugs that have a similar molecular structure. Opium is a dried milky substance obtained from the opium poppy. Opioids have medicinal value as powerful analgesics (painkillers). Morphine and codeine are familiar medications traditionally made from the opium poppy. Heroin was originally developed by the Bayer pharmaceutical company as a replacement for morphine. Today, opioid drugs are available legally only with a prescription from a doctor, and they are meant to treat severe pain.

Today, most prescription opioid painkillers are partly or totally synthetic. These opioids include hydromorphone (sold under the name Dilaudid); hydrocodone (combined with acetaminophen under the brand name Vicodin); and oxycodone (combined with aspirin under the brand name Percodan). Oxycodone is an opioid drug made from a chemical in the opium poppy called thebaine. A popular slow-release form of the drug is sold under the brand name OxyContin. Like their chemical cousin heroin, synthetic opioids can cause people to become physically dependent or addicted.

For many people, addiction to opioids often begins at the doctor’s office or after a visit to the emergency room. When administered under a doctor’s care, opioids are safe and effective. But should patients continue using these powerful drugs, as they increasingly do for conditions that result in chronic pain, the risk of addiction becomes very real. The same chemistry by which prescription opioids dull severe pain can also lead to crippling addiction and drug abuse—and often overdose and death.

After prescriptions run out or become too expensive, addicted people may resort to buying heroin on the street. Despite being illegal, heroin is widely available and cheaper than prescription pills. Heroin is often mixed with other ingredients or spiked with fentanyl, a synthetic opioid 50 times more potent than heroin.

Fentanyl overdoses have overtaken those caused by heroin in some regions of the United States, and the opioid has been increasingly found among drugs seized by law enforcement officers across the country. Fentanyl and other synthetics with a similar chemical structure, called fentanyl analogues, are so powerful that doses equal to the amount of a few grains of salt can be lethal.

Naloxone is a temporary antidote for opioid overdoses, including those caused by Fentanyl. When properly administered it can restore normal breathing and consciousness to opioid overdose victims. Credit: Dennis Yip, Fentanyl Safety

A drug called naloxone, marketed under the brand name Narcan, is used to treat opioid overdose in emergency situations. The drug blocks or reverses the effects of opioids, which include extreme drowsiness, slowed breathing, and loss of consciousness. Naloxone is administered through an injection. However, emergency medical teams may be unable to revive people who overdose on fentanyl analogues even after multiple injections of naloxone.

As demand for naloxone has increased in response to the opioid epidemic, the price of the drug has followed suit. Many towns and counties burned through their annual budgets for the life-saving drug half way through 2017. Cash-strapped state and local emergency medical response teams are being pushed to the limit because of the crisis. This drain on resources prevents communities from dealing adequately with other medical care needs, further darkening the nation’s health care situation.

Opioid drugs remain an essential treatment for patients with severe pain, and the United States Food and Drug Administration (FDA) requires all manufacturers of such drugs to demonstrate that they are both safe and effective. However, medical experts recognize that more needs to be done to prevent opioid treatment from escalating to addiction.

Medical experts believe that solving the current opioid crisis is more than a matter of law enforcement cutting off the supply of illegally obtained opioid drugs. Treatment for addicts and education programs that emphasize prevention and the seeking of help are also vitally important. Medical experts at the FDA have proposed a policy of “opioid exceptionalism” for prescribing pain medications. Before prescribing opioids to treat pain, doctors would be instructed to consider the risks that a patient might develop an opioid use disorder or become addicted. Doctors would also consider the risk of addicted patients making a transition to other opioids or turning to illicit drugs such as heroin.

In March 2017, President Donald Trump appointed a commission to investigate the opioid crisis. On July 31, the commission recommended that the president declare a national emergency to deal with the epidemic. Public health experts agreed that such bold action is necessary to help Americans understand the severity of the opioid epidemic and to recognize that it is an unparalleled crisis requiring urgent attention.

The opioid commission’s report called for increasing access to naloxone and other medications used to treat overdose or addiction and requiring opioid drug prescribers to receive more education about the proper use of these drugs. The commission also proposed waiving a federal rule that limits addiction treatment for people who receive health care from government-funded Medicaid.

The federal report echoed similar reports from state and local counterparts across the United States. Medical experts emphasized that federal actions to complement state and local efforts help reduce rates of opioid dependence, overdose, and deaths, giving communities the greatest chance of success for ending the current crisis. President Trump, however, dismissed many of the findings detailed in the commission’s report. Instead, he focused on issues unrelated to the opioid crisis, such as stopping the influx of illicit drugs at the border with Mexico. Trump’s insistence on repealing the Affordable Care Act (commonly known as Obamacare) would risk making matters worse by stripping funding for Medicaid—so far the best source of government help for curbing the epidemic.

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.

October 2, 2014

Texas health officials are checking as many as 100 people for exposure to Ebola. They include all “potential or possible contacts” with Thomas Eric Duncan, a Liberian man diagnosed with Ebola in Dallas on September 30. His is the first case diagnosed outside of West Africa, where more than 3,300 people have died in the current Ebola outbreak.

Duncan is believed to have contracted the virus in Liberia before he flew to the United States nearly two weeks ago to visit relatives. He initially sought medical attention for a low-grade fever and abdominal pain on September 25. Blood tests were performed, but he was not screened for the Ebola virus, despite the fact that he had informed a nurse that he had recently arrived from Liberia. The Ebola epidemic is raging in Liberia as well as Guinea and Sierra Leone. Duncan was given antibiotics and a pain reliever and sent home, where his condition rapidly deteriorated.

The ebola virus causes Ebola hemorrhagic fever, an illness characterized by fever, headache, diarrhea, vomiting, and massive internal bleeding. About 80 to 90 percent of all people who become infected die. There is no cure or vacccine for Ebola virus. (Centers for Disease Control and Prevention: Frederick A. Murphy)

On September 28, Duncan’s nephew contacted the Center for Disease Control (CDC). “I called CDC to get some actions taken because I was concerned for his life and he was not getting the appropriate care,” the nephew, Josephus Weeks, stated in a television interview. “And I feared that other people might get infected if he was not taken care of.” CDC officials instructed Weeks to call the Texas Department of Health, which moved Duncan into an isolation unit at a Dallas hospital.

The commissioner of Texas State Health Services, David Lakey, today confirmed that four of Thomas Eric Duncan’s “close relatives” are under a quarantine order until October 19. The medical technicians who rushed the patient to the hospital are also being monitored. “We have tried and true protocols to protect the public and stop the spread of this disease,” declared Dr. Lakey. “This order gives us the ability to monitor the situation in the most meticulous way.”

Thomas Eric Duncan remains in isolation in stable but serious condition.

Additional World Book article:

• Disease Detectives (a special report)
• The Origin of New Diseases (a special report)

July 28, 2014

The worst recorded epidemic of the deadly and highly contagious Ebola virus led the West African nation of Liberia today to close most of its border crossings. Liberia is one of three nations, along with Sierra Leone and Guinea, that are being hard hit by the virus. Liberia’s President Ellen Johnson-Sirleaf also issued restrictions on public gatherings and said areas hit by the virus could be quarantined. The current outbreak of Ebola hemorrhagic fever, which began in  March in southern Guinea, has killed at least 670 people, including the Liberian doctor who was heading his country’s efforts to contain the epidemic. Yesterday, Nigeria’s Arik Air suspended all flights into Sierra Leone and Guinea after Nigerian officials confirmed the first Ebola death in Lagos, Nigeria’s capital and the most populous city in Africa. Meanwhile, medical workers in Guinea were meeting hostility and resistance from residents who blamed them for spreading the disease.

Ebola hemorrhagic fever is characterized by massive internal bleeding as well as diarrhea and vomiting. It is spread by direct contact with such bodily fluids as saliva and blood and by contact with towels and other objects cotaminated by the virus. While animals, including chimpanzees and gorillas, can transmit the virus, the natural source is unknown. There is no cure or vaccine for the disease. Symptoms appear within 5 to 10 days of infection. About 80 to 90 percent of all people who become infected die, though patients who receive treatment while in the early stages of the disease have a slightly better chance of recovery. Treatment consists mainly of rehydration to replace lost body fluids.

The current Ebola outbreak began in southern Guinea in March and has spread to Liberia and Sierra Leone. (World Book map; map data © MapQuest.com, Inc.)

As of July 20, Ebola had killed 454 people in Sierra Leone; 314 in Guinea; and 224 in Liberia, according to the World Health Organization (WHO). Forty-five cases, including 28 deaths, were reported in those three countries between July 18 and 20 alone.

Most hemorrhagic viruses have a host, often a rodent or insect, which carries the virus but does not become ill. Scientists have not yet identified the host for the Ebola virus. However, the bushmeat trade is highly suspected of spreading the virus among people. The WHO has warned people against eating raw bushmeat and avoiding contact with infected apes, bats, and monkeys.

Additional World Book article:

• Disease Detectives (a special report)
• The Origin of New Diseases (a special report)

June 16, 2014

In a series of controversial experiments, scientists at the University of Wisconsin in Madison have re-created in a laboratory a strain of influenza virus that closely resembles the virus responsible for the Spanish flu pandemic (global occurrence) of 1918 that killed over 50 million people worldwide. The scientists contend that they re-created the deadly virus as a necessary step to help combat future flu pandemics. However, critics of the research argued that the experiments should be halted immediately as they pose a great threat to public safety.

Influenza tends to occur in widespread epidemics that occur most every year. Each outbreak is caused by a virus slightly different from earlier ones. Some strains (types) cause mild or moderate illness, and others cause many deaths. The Spanish flu of 1918 was the deadliest outbreak of influenza in history. Medical historians believe the Spanish flu virus, like many strains of influenza, probably originated in Asia. The disease quickly spread to the United States, Europe, Africa, and South America. During the height of the pandemic, the huge number of deaths severely disrupted many societies. Less severe pandemics occurred in 1957 and in 1968 but still resulted in many deaths.

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

The Wisconsin scientists, led by Yoshihiro Kawaoka, isolated several genes from influenza viruses that normally infect wild ducks in Asia. These “avian influenza” (also known as “bird flu) viruses often mutate so they can infect mammals, including humans, and spread in global pandemics. Using a technique known as “reverse genetics,” the scientists used the individual genes to reconstruct an entire flu virus. They compared this rebuilt virus to virus samples from frozen corpses of victims of the 1918 Spanish flu pandemic recovered in Alaska. The rebuilt virus was 97 percent identical to the deadly Spanish flu virus.

The scientists infected ferrets with the re-created virus so they could study how it infected and spread among mammals. Kawaoka contends that such experiments are important so scientists can understand why the 1918 Spanish flu virus was so lethal, compared to other strains of flu that originate in wild birds. For example, the scientists identified a mutation in the rebuilt virus that enabled it to spread more easily from one animal to another. Scientists argue that continued research will help them better understand how the virus infects animals and makes them ill. This information will be useful for developing effective vaccines and treatments to combat future flu pandemics.

Other scientists argue that the research is too dangerous to continue and that another Spanish flu pandemic is unlikely to occur naturally. They claim that the most serious risk lies with the rebuilt virus being released from the high-security laboratory through some accident. Should an infected research animal escape, the deadly virus could spread rapidly in a new global pandemic with catastrophic results. The United States National Institutes of Health (NIH) which funds the controversial research, insisted that proper safety measures are being taken and that funding for the research would continue.

Additional World Book articles:

• SARS
• Swine flu
• Influenza: A New Threat from an Old Foe (a Special Report)
• Medicine in the 21st Century: The Promise of Genetics (a Special Report)

January 11, 2013

Three separate flu or flu-like epidemics are emerging simultaneously across North America. The first includes an unusually aggressive flu virus that is showing up earlier than usual. The second is a surge of cases from a new type of norovirus. The third is a whooping cough outbreak, the worst in 60 years.

Forty-seven states reported that the flu had become widespread during the week ending January 5, up from 41 states the previous week, the Centers for Disease Control and Prevention (CDC) announced today. The most common strain currently moving across the county is an H3N2. This strain is more lethal than H1N1, the strain that typically appears in the United States at this time of year. The number of flu cases is currently “elevated” across the United States, except in Arizona, California, Hawaii, and Nevada. However, 24 states and New York City have reported “high levels” of flu-like illness to the CDC. On January 9, the mayor of Boston declared a public health emergency because of the number of flu cases flooding the city’s hospital emergency rooms. Across the United States, more than 3,700 people, primarily senior citizens, have been hospitalized with the flu and at least 20 children have died from the H3N2 strain since the season began this fall.

Cities across Canada have reported outbreaks of norovirus so serious that hospitals are shutting down and disinfecting whole wards because patients were becoming infected after checking in with a different ailment. The new strain is known as the Sydney 2012 variant, because it first appeared in Australia. The classic symptoms are “explosive” diarrhea and “projectile” vomiting.

Flu is caused by a virus, such as the ones above, which have been greatly enlarged and artificially colored. (© Linda Stannard, UCT/SPL from Photo Researchers)

In early January, the CDC reported 42,000 confirmed cases of whopping cough in the United States in 2012, the biggest outbreak in  60 years. The disease is unrelated to flu but causes a hacking, constant cough and breathlessness. Infants, especially premature infants, are at greatest risk. There were 18 recorded deaths from whopping cough in the United States in 2012.

The CDC and the local health authorities strongly advocate getting flu shots. Based on data from some 1,155 children and adults with acute respiratory infections, flu vaccines are judged to be 62-percent effective. William Schaffner, chairman of the department of preventive medicine at Vanderbilt University in Nashville, Tennessee, has characterized this level of effectiveness as “normal.” “It’s a good but not a perfect vaccine,” he noted.

Additional World Book articles:

• Spanish flu
• Swine Flu
• Disease Detectives (a special report)
• Influenza: A New Threat from an Old Foe (a special report)
• Public health 2009 (a Back in Time article)

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)