What is smallpox and how does it spread. How has smallpox impacted human history. What are the symptoms of smallpox. How was smallpox eradicated globally. Why is smallpox still a concern today. What are the current vaccination policies for smallpox. How does the smallpox vaccine work and what are its risks.

The Historical Impact of Smallpox on Humanity

Smallpox, caused by the Variola major virus, has left an indelible mark on human history. Over the centuries, this highly contagious disease has claimed countless lives, with some experts asserting that it has caused more deaths than all other infectious diseases combined. The profound impact of smallpox on populations worldwide cannot be overstated.

How did smallpox shape the course of history? The disease played a significant role in the conquest of the Americas, decimating indigenous populations who had no immunity to the virus brought by European explorers. It also affected the outcomes of numerous wars and conflicts throughout history, as armies weakened by smallpox outbreaks often faced defeat.

Notable Smallpox Outbreaks in History

• The Antonine Plague (165-180 AD): Believed to be smallpox, it devastated the Roman Empire
• The conquest of the Aztec Empire (1519-1521): Smallpox played a crucial role in the fall of Tenochtitlan
• The Great Plague of London (1665-1666): While primarily a bubonic plague outbreak, smallpox also contributed to the high death toll
• The American Revolutionary War (1775-1783): Smallpox outbreaks affected both British and Continental armies

The Global Eradication of Smallpox: A Triumph of Modern Medicine

The eradication of smallpox stands as one of the greatest achievements in the history of public health. How was this seemingly impossible feat accomplished? The World Health Organization (WHO) launched an intensive global vaccination campaign in 1967, which ultimately led to the last known natural case of smallpox in Somalia in 1977.

This remarkable success was officially declared by the WHO in 1980, marking smallpox as the first and only human disease to be completely eradicated through vaccination efforts. The eradication campaign’s strategies included:

1. Mass vaccination in endemic areas
2. Surveillance and containment of outbreaks
3. Targeted vaccination of contacts of infected individuals
4. International cooperation and coordination

Understanding Smallpox Transmission and Symptoms

Smallpox is highly contagious and spreads easily from person to person. The primary mode of transmission is through respiratory droplets during close face-to-face contact. The virus can also spread through direct contact with contaminated bodily fluids or objects such as bedding or clothing.

What are the telltale signs of smallpox infection? The initial symptoms are often flu-like and include:

• High fever
• Severe fatigue
• Headache
• Intense back pain

These initial symptoms are followed by the development of a characteristic rash. How does the smallpox rash progress? The rash typically appears first on the face, arms, and legs, then spreads to the trunk. It evolves through several stages:

1. Macules (flat red spots)
2. Papules (raised bumps)
3. Vesicles (fluid-filled blisters)
4. Pustules (pus-filled lesions)
5. Scabs (crusted lesions that eventually fall off)

The Absence of Smallpox Treatment and Its Consequences

Despite its historical significance and devastating effects, there is no specific treatment for smallpox. How do medical professionals manage smallpox cases? The approach focuses on supportive care, including:

• Maintaining hydration through fluid replacement
• Administering pain relief medications
• Managing fever with appropriate medications
• Preventing secondary bacterial infections

While most people recover from smallpox, the disease can be fatal in some cases. The mortality rate varies depending on the strain of the virus, with the most severe form (Variola major) having a mortality rate of about 30%. Those who survive smallpox often bear permanent scars, particularly on the face, and may experience complications such as blindness or limb deformities.

The Current Status of Smallpox and Bioterrorism Concerns

Although smallpox has been eradicated in the wild, the virus still exists in two high-security laboratories: the Centers for Disease Control and Prevention (CDC) in Atlanta, USA, and the State Research Center of Virology and Biotechnology (VECTOR Institute) in Koltsovo, Russia. Why are these samples kept? They are maintained for research purposes and to develop defenses against potential bioterrorist attacks.

The possibility of smallpox being used as a biological weapon is a significant concern for public health officials and national security experts. Why is smallpox considered a potential bioterror threat?

• High infectivity and ease of person-to-person spread
• Significant morbidity and mortality rates
• Lack of effective treatment options
• Declining population immunity due to cessation of routine vaccination

Smallpox Vaccination: Past Practices and Current Policies

Routine smallpox vaccination in the United States ended in 1972, following the global eradication effort. However, certain groups continue to receive the vaccine due to their higher risk of exposure. Who still receives smallpox vaccinations today?

• Military personnel deployed to high-risk areas
• Laboratory workers handling orthopoxviruses related to smallpox
• Healthcare workers and first responders designated for smallpox response teams

In recent years, the United States has increased its stockpile of smallpox vaccines as a precautionary measure against potential bioterrorist attacks. How many doses of smallpox vaccine does the U.S. maintain? The Strategic National Stockpile contains enough vaccine to inoculate every U.S. citizen in the event of a smallpox emergency.

The Smallpox Vaccine: Efficacy and Potential Risks

The smallpox vaccine, which contains live vaccinia virus (a related but less harmful poxvirus), is highly effective in preventing smallpox infection. How does the smallpox vaccine work? It stimulates the immune system to produce antibodies that protect against smallpox, with immunity lasting for several years after vaccination.

However, the vaccine is not without risks. What are the potential side effects of the smallpox vaccine?

• Mild reactions: fever, body aches, and swelling at the injection site
• Serious complications (rare): myocarditis, encephalitis, or severe skin reactions
• Life-threatening reactions (very rare): particularly in individuals with weakened immune systems

Due to these risks, the vaccine is not recommended for the general public in the absence of a smallpox outbreak. Instead, it is reserved for those at highest risk of exposure or for use in the event of a bioterrorist attack involving smallpox.

Lessons from Smallpox: Implications for Future Pandemics

The successful eradication of smallpox offers valuable lessons for managing other infectious diseases and potential pandemics. What can we learn from the smallpox eradication campaign?

1. The importance of global cooperation in public health initiatives
2. The power of vaccination in controlling and eliminating diseases
3. The need for sustained surveillance and rapid response to outbreaks
4. The value of targeted interventions and ring vaccination strategies

These lessons have informed approaches to other disease eradication efforts, such as the ongoing campaign to eliminate polio. They also provide insights for managing emerging infectious diseases and potential future pandemics.

Applying Smallpox Lessons to Modern Challenges

How can the experiences from smallpox eradication be applied to current and future health challenges? Consider the following applications:

• Developing and distributing vaccines for emerging diseases
• Implementing contact tracing and isolation strategies
• Fostering international collaboration in disease surveillance and response
• Balancing individual rights with public health needs during outbreaks

The legacy of smallpox and its eradication continues to influence public health policies and practices worldwide, shaping our approach to global health security in the 21st century.

The Future of Smallpox Research and Preparedness

Despite the eradication of smallpox in the wild, research on the virus continues in secure laboratory settings. Why is ongoing smallpox research important? It serves several crucial purposes:

• Developing improved vaccines with fewer side effects
• Creating antiviral treatments for potential smallpox infections
• Enhancing diagnostic capabilities for rapid detection
• Studying the virus’s biology to better understand other poxviruses

How are countries preparing for the unlikely event of a smallpox outbreak? Many nations maintain emergency response plans that include:

1. Stockpiles of smallpox vaccine
2. Training programs for healthcare workers
3. Surveillance systems to detect potential cases
4. Communication strategies to inform and guide the public

These preparedness measures reflect the ongoing vigilance required to protect global health security, even against diseases that have been eradicated in nature.

Ethical Considerations in Smallpox Research

The continued existence of smallpox virus samples in laboratories raises important ethical questions. What are the key ethical considerations surrounding smallpox research?

• Balancing scientific knowledge gain against potential risks of accidental release
• Ensuring equitable access to any new treatments or vaccines developed
• Addressing concerns about dual-use research that could be misused for harmful purposes
• Determining the long-term fate of remaining smallpox virus stocks

These ethical debates underscore the complex interplay between scientific advancement, public health, and global security in the post-eradication era of smallpox.

Smallpox in Popular Culture and Public Perception

The historical significance and devastating nature of smallpox have left a lasting impression on human culture and collective memory. How is smallpox represented in literature, film, and other media? The disease often appears as a symbol of fear, devastation, and the vulnerability of human populations to infectious threats.

Notable examples of smallpox in popular culture include:

• Historical novels depicting smallpox outbreaks in various eras
• Science fiction stories exploring bioterrorism scenarios involving engineered smallpox
• Documentaries chronicling the global eradication campaign
• Video games featuring smallpox as a plot device or game mechanic

These cultural representations both reflect and shape public perception of smallpox, influencing attitudes towards vaccination, public health measures, and the broader concept of global health security.

Impact on Risk Perception and Health Behaviors

How does the cultural memory of smallpox affect modern attitudes towards health and disease? The legacy of smallpox continues to influence:

1. Public trust in vaccination programs
2. Support for global health initiatives
3. Perceptions of emerging infectious disease threats
4. Attitudes towards biomedical research and public health interventions

Understanding these cultural impacts is crucial for effective public health communication and policy-making in the face of current and future disease threats.

The Role of Smallpox in Shaping Modern Epidemiology

The study and eradication of smallpox have significantly contributed to the development of modern epidemiology and public health practices. How has smallpox influenced the field of epidemiology?

• Establishing principles of disease surveillance and outbreak investigation
• Developing strategies for targeted vaccination and containment
• Advancing understanding of virus transmission and host-pathogen interactions
• Informing mathematical models of disease spread and intervention effectiveness

These contributions have laid the groundwork for managing a wide range of infectious diseases, from seasonal influenza to emerging pathogens like COVID-19.

Lessons for Managing Future Disease Threats

What specific lessons from smallpox can be applied to current and future epidemics? Key takeaways include:

1. The importance of early detection and rapid response
2. The value of international cooperation and data sharing
3. The effectiveness of ring vaccination strategies in containing outbreaks
4. The need for clear communication and public education during health crises

By applying these lessons, public health officials and policymakers can enhance preparedness and response capabilities for a wide range of potential health threats.

Smallpox and the Evolution of Medical Ethics

The history of smallpox and efforts to combat it have played a significant role in shaping modern medical ethics. How has smallpox influenced ethical considerations in medicine and public health?

• Informed consent in vaccination programs
• Balancing individual rights with community health needs
• Ethical considerations in human subjects research
• Equitable distribution of medical resources during outbreaks

These ethical principles, developed in part through experiences with smallpox, continue to guide medical practice and public health policy today.

Contemporary Ethical Debates

What current ethical issues relate to the legacy of smallpox? Ongoing debates include:

1. The ethics of maintaining live smallpox virus stocks for research
2. Balancing biosecurity concerns with scientific openness
3. Addressing vaccine hesitancy and misinformation
4. Ensuring global equity in access to vaccines and treatments

These discussions reflect the enduring impact of smallpox on medical ethics and public health policy, even decades after its eradication.

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Smallpox is a disease caused by the Variola major virus. Some experts say that over the centuries it has killed more people than all other infectious diseases combined. Worldwide vaccination stopped the spread of smallpox three decades ago. The last case was reported in 1977. Two research labs still keep small amounts of the virus. Experts fear bioterrorists could use the virus to spread disease.

Smallpox spreads very easily from person to person. Symptoms are flu-like. They include:

• High fever
• Fatigue
• Headache
• Backache
• A rash with flat red sores

There is no treatment. Fluids and medicines for pain or fever can help control symptoms. Most people recover, but some can die. Those who do recover may have severe scars.

The U.S. stopped routine smallpox vaccinations in 1972. Military and other high-risk groups continue to get the vaccine. The U.S. has increased its supply of the vaccine in recent years. The vaccine makes some people sick, so doctors save it for those at highest risk of disease.

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• Smallpox/Monkeypox Vaccine Information Statement

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• Vaccine Basics: Smallpox

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• ClinicalTrials. gov: Smallpox

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• Article: Evaluation of Monkeypox- and Vaccinia virus-neutralizing antibodies in human serum samples. ..

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What Is Smallpox? Symptoms, Causes, Diagnosis, Treatment, and Prevention

By Joseph Bennington-CastroMedically Reviewed by Jane Yoon Scott, MD

Reviewed: April 30, 2023

Medically Reviewed

The international effort to eradicate smallpox, once a deadly and disfiguring global disease, was a huge public health achievement. Alamy

Smallpox is a highly infectious disease caused by a virus.

Its hallmark symptom is a distinctive rash that changes in appearance as the disease progresses. (1,2)

Smallpox is deadly, killing around 3 in 10 people who are infected. Some experts estimate that in the 20th century alone, smallpox was responsible for 300 million deaths. (3)

A global smallpox immunization campaign led to the eradication of the disease in the late 1970s.

Today, two government research laboratories — one in the United States and the other in Russia — hold the last remaining stores of the virus responsible for smallpox. (4)

Common Questions & Answers

Is there still smallpox today?

By the late 1970s, a global immunization campaign had eradicated the disease, so the virus no longer exists out in the world. But two labs — one in the United States and one in Russia — still hold virus samples for research purposes.

What is smallpox caused by?

Smallpox is caused by the variola virus. This virus belongs to the same genus (Orthopoxvirus) as the one that causes monkeypox.

Can humans survive smallpox?

Most people diagnosed with smallpox can survive it, but they may be left blind or deeply scarred by the rash. For people at heightened risk, such as the immunocompromised or those who are pregnant, smallpox can be fatal.

Is smallpox curable now?

Tecovirimat, cidofovir, and brincidofovir are three antivirals that could treat smallpox. They’ve been shown to be effective in labs and in animals, and the Centers for Disease Control and Prevention (CDC) has stockpiled tecovirimat and cidofovir in case of a public health emergency.

Signs and Symptoms of Smallpox

After a person is infected with the variola virus, there is a nonsymptomatic incubation period during which the virus replicates in the body. This stage lasts anywhere from 7 to 19 days, with an average of 10 to 14 days.

The first symptoms are usually:

• High fever
• Headaches
• Body aches, including backaches
• Vomiting

These symptoms typically last two to four days and are severe enough to prevent normal day-to-day activities.

Other possible symptoms may include:

• Chills
• Severe abdominal pain
• Fatigue
• Delirium
• Diarrhea
• Malaise
• Nausea
• Excessive bleeding (1,5,6)

After the first symptoms of headaches, fever, and body aches, the next sign of the disease to appear is a rash, beginning with small, flat red spots on the tongue and in the mouth.

The rash develops into sores that break open. Typically within a day, the rash spreads to the face and then to the arms and legs, followed by the hands, feet, and the rest of the body.

As the rash develops, the fever may go down, causing infected people to feel like they’re getting better.

Within a couple of days, the rash turns into small red bumps that look like blisters. By the fourth day of the rash, the spots transform into sores that fill with a thick, opaque fluid and have a dent in the center.

The fever may then resume for the duration of the rash.

The crater-like sores turn into pustules (pus-filled lesions), becoming sharply raised, round, and firm to the touch. These pustules may break open, oozing and becoming bloody.

After about five days, the pustules begin to form a crust and then scab over. Most sores reach this stage by the end of the second week of the rash.

The scabs fall off after about one more week, leaving deep pockmarks. (5,7,8)

Causes and Risk Factors of Smallpox

Smallpox is caused by the variola virus, which, along with the vaccinia virus, monkeypox virus, and cowpox virus, belongs to the genus Orthopoxvirus.

There are two species of variola virus — Variola major and Variola minor. The first can lead to life-threatening illness, while the second rarely results in death. (1)

Humans are the only known carriers of the variola virus. Other Orthopoxvirus viruses are normally transmitted to humans from infected animals. (6)

How Is Smallpox Transmitted?

Smallpox is most contagious after the rash develops. Transmission occurs through:

• Prolonged face-to-face contact with someone infected with the variola virus, who may spread it through saliva by coughing, sneezing, or speaking
• Contact with an infected person’s bodily fluids, especially fluid from blisters on the skin
• Touching items that have been contaminated with the variola virus (via scabs or fluid from sores), such as blankets, towels, or clothes — the virus can survive outside the body for up to 24 hours (1)
• Breathing in the virus if it has become airborne and circulated through a ventilation system, such as one in a small office, bus, or train (9,10,11)

How Is Smallpox Diagnosed?

Many illnesses can cause rashes. But it’s highly unlikely that a person with a rash has smallpox.

The major diagnostic criteria for smallpox are:

• A fever of at least 101 degrees F (38.3 degrees C), which develops one to four days before a rash and is accompanied by at least one other symptom, including extreme weakness, headache, backache, chills, vomiting, or severe abdominal pain
• Classic smallpox lesions as described above
• Lesions that are in the same stage of development on any one part of the body (such as having only pustules on the arms, rather than a mix of pustules and blisters)

If a person meets the above criteria it’s highly likely they have smallpox. Minor diagnostic criteria (lower likelihood) include:

• A rash with the greatest concentration of lesions on the face and extremities
• Lesions that first appear in the mouth or on the face or forearms
• Extreme illness
• Rash that evolves into different forms slowly
• Lesions on the palms of the hands or soles of the feet

Laboratory tests can rule out other potential diagnoses, such as chicken pox, and confirm a smallpox diagnosis. (12)

How Does Smallpox Differ From Chicken Pox?

Though both smallpox and chickenpox cause fever and rash, the two diseases are not the same.

Chickenpox is caused by the varicella zoster virus, a type of alpha herpesvirus (not belonging to the Orthopoxvirus genus). Though chickenpox can sometimes cause serious complications, the illness is often mild. (13)

There are also differences between smallpox and chickenpox rashes.

Chickenpox rash often develops soon after other symptoms begin (if there are any) and looks like small blisters; the itchy lesions develop one after another, rather than all at once in a single area; and the lesions change rapidly, usually forming scabs within 24 hours. (14,15)

Duration of Smallpox

Smallpox has an average incubation period of 10 to 14 days, during which the person has no symptoms.

Initial symptoms last for two to four days and typically include high fever, headaches and body aches, and sometimes vomiting. The person may be contagious during this phase.

A person is most contagious over the next four days, when a red rash appears and spreads, then turns into fluid-filled sores.

The next phase, in which the sores become pustules, then form into scabs, lasts about 10 days.

It takes about six days for the scabs to fall off. At this point, the person is no longer contagious. (5,9)

Treatment and Medication Options for Smallpox

In the past, smallpox treatment focused on relieving symptoms and preventing the spread of the disease by isolating the patient until all the smallpox scabs fell off. (17)

But in recent years, researchers have developed antiviral medications for smallpox.

In 2018, the U.S. Food and Drug Administration (FDA) approved the drug tecovirimat (TPOXX) to treat smallpox. The drug works by inhibiting the activity of a protein called p37, which ultimately prevents viral particles from leaving an infected cell and spreading to other cells. (18)

Research shows that tecovirimat is effective against the variola virus in laboratory settings (in cell cultures) and can treat diseases similar to smallpox in animals. Studies also show tecovirimat is safe, with the most frequent side effects being headache, nausea, and abdominal pain.

But since the drug was developed after the eradication of smallpox, it hasn’t been tested on human subjects, causing some uncertainty about how well it would work in the unlikely event of an outbreak.

Other studies have shown that the antiviral drugs cidofovir (Vistide), which is sometimes used to treat an eye infection called cytomegalovirus retinitis in people with AIDS, and brincidofovir, which is an experimental drug also used to treat cytomegalovirus retinitis as well as adenovirus, are effective against smallpox in lab settings and can treat smallpox-related diseases in animals.

Neither cidofovir nor brincidofovir have been tested on people with smallpox. Scientists continue to study the drugs’ effectiveness and toxicity.

The CDC has stockpiles of tecovirimat and cidofovir in case of a public-health emergency. (19)

Prevention of Smallpox

Healthcare workers no longer routinely administer smallpox vaccines to the general public. The CDC recommends smallpox vaccination only for laboratory researchers who study the variola virus or its close relatives.

Still, the CDC has stockpiles of smallpox vaccine — enough to give one to every person in the United States if necessary. (20)

The original smallpox vaccine contains live vaccinia virus, which is in the same Orthopoxvirus genus as the variola virus but causes a less severe illness. Exposure to the vaccinia virus prompts the immune system to produce antibodies that are also effective against the variola virus.

This method of gaining smallpox immunity was first developed by the English doctor Edward Jenner. In 1796, after observing that milkmaids who got cowpox never developed smallpox, he took material from a cowpox sore and inoculated it into the hand of his gardener’s 9-year-old son. Then he repeatedly exposed the boy to the variola virus — and the child did not develop smallpox.

Sometime in the 1800s, the virus used to make the smallpox vaccine switched from cowpox to vaccinia. (4)

The smallpox vaccine prevents infection in 95 percent of those who receive it, and is also able to prevent or lessen infection when given within a few days of exposure to variola virus.

The smallpox vaccine can’t help people with advanced infection who are already developing a rash. (21)

Since the eradication of smallpox, scientists have developed a newer version of the vaccine that uses attenuated (weakened) viral strains. This vaccine is suitable for people who can’t take the original vaccine, such as those who are pregnant, have a weakened immune system, or have had a bone-marrow transplant.

The new smallpox vaccine hasn’t been tested against the variola virus in people, so its effectiveness is still unproven. (22)

Side Effects of the Smallpox Vaccine

Unlike most other vaccines, the smallpox vaccine does not involve an injection or “shot. ”

Instead, it’s administered with a bifurcated (two-pronged) needle that is first dipped into the vaccine solution. A doctor uses the needle to prick the skin (usually in the upper arm) multiple times in a few seconds.

A successful vaccination causes a red and itchy lesion to develop at the vaccine site within three to four days. This lesion turns into a large blister that fills with pus and begins to drain in the first week. It begins to dry and scab over in the second week and then falls off (leaving a small scar) in the third week. (21)

During this process, the vaccinia virus can be easily transferred to another part of the body or even another person through touch. Touching the vaccination sore and then the eye can lead to a serious infection that can threaten vision. The vaccination sore may also develop into a serious toxic or allergic rash.

Rarely, people develop other significant or even life-threatening reactions to the vaccine, including:

• Inflammation of the heart, heart lining, or both
• Heart pain and heart attack
• Serious rash called eczema vaccinatum (in people with preexisting skin conditions, particularly eczema or atopic dermatitis, who got infected with the vaccinia virus from someone else who was vaccinated)
• Progressive vaccinia, or a buildup of inflamed tissue at the vaccination site, in people with a weakened immune system
• Brain inflammation

Research suggests these complications kill one or two people out of every million vaccinated for smallpox. But most people who get the smallpox vaccine experience only mild reactions. These may include:

• Pain and redness at the vaccination site
• Swollen lymph nodes in the armpits
• Low-grade fever
• Trouble sleeping
• General malaise that interferes with daily activities (1,23)

Complications of Smallpox

In addition to causing changes to the skin, smallpox affects the body’s internal organs.

When sores in the mouth break open, the virus infects the trachea and lungs. But before the virus can spread much farther, it needs to replicate. Research suggests this likely happens in the lymphoid organs, specifically the spleen, bone marrow, and lymph nodes.

After replication, the virus can move into the bloodstream, causing secondary infections of other organs:

• The cells lining the small blood vessels of the liver often become swollen and die, and the liver becomes much heavier than normal.
• Certain cells in the bone marrow and spleen become enlarged.
• The spleen becomes engorged and fills with many large lymphoid cells.
• The brain may become inflamed (encephalitis).

Smallpox can also cause eye infections, pneumonia, arthritis, and bone infections. (1)

Death from smallpox usually results from high blood pressure, issues with blood coagulation, and cardiovascular collapse.

Some people develop a severe, rare form of smallpox called hemorrhagic smallpox, which causes bleeding, especially of the skin, the mucous membranes throughout the body, and the gastrointestinal tract. (24)

Most people diagnosed with smallpox survive, but they can be left deeply scarred or blind. For people at heightened risk, such as those who are pregnant or immunocompromised, smallpox can be fatal. (10)

Research and Statistics: Who Has Smallpox Now?

Because smallpox has been eradicated, the variola virus no longer exists in the world.

But the virus can be found inside laboratories for research purposes. In 1981, just four labs — in the United States, England, Russia, and South Africa — kept variola virus.

By 1984, England and South Africa had either destroyed their variola stocks or transferred them to other approved labs, leaving only two labs with the virus: the CDC, headquartered in Atlanta, and the State Research Center of Virology and Biotechnology (VECTOR Institute) in Koltsovo, Russia. (4)

There is some concern that these stores could be stolen and used in a bioterrorism attack. While this risk is low, the CDC has an emergency plan in place and continues to develop new vaccines and medications. (25)

In an unsettling 2014 incident, scientists cleaning out an old laboratory on the National Institutes of Health campus in Bethesda, Maryland, found vials labeled “variola.” The CDC collected the vials and brought them to Atlanta. (26) A similar incident occurred in November 2021, at a Merck vaccine research facility in Pennsylvania, but no one was exposed.

RELATED: Vials Labeled ‘Smallpox’ Found at Merck Facility Outside Philadelphia

History of Smallpox

While no one has smallpox now, this disease has been a threat to public health for thousands of years.

Archaeologists found smallpox-like rashes in three Egyptian mummies from the third century B.C., as well as on the mummy of Ramses V, who died in 1157 B.C. But these lesions may have been caused by many other diseases, including those produced by other poxviruses.

Ancient Indian treatises provide the first reliable descriptions of smallpox, though it’s unclear how old these medical texts are. Some experts date the treatises to the sixth century B.C., while others claim they go all the way back to the 15th century B.C.

In China, the first reliable description of smallpox was in the fourth century A.D., though some evidence suggests the disease first appeared there in the third century B.C. (27)

Exploration and trade over the centuries helped smallpox go global.

Smallpox reached Japan in the sixth century A.D.; northern Africa, Spain, and Portugal in the seventh century; and Central and South America in the 16th century. North America saw its first cases of smallpox in the 17th century, while Australia did in the 18th century.

In 1959, the World Health Organization initiated a vaccination program to rid the world of smallpox and launched renewed efforts in 1967 with its intensified eradication program.

In 1975, a 3-year-old girl from Bangladesh named Rahima Banu was the last person on the planet to naturally acquire variola major; in 1977, a hospital cook in Somalia named Ali Maow Maalin was the last person to have naturally acquired variola minor.

In 1978, a woman named Janet Parker became the last known person to die of smallpox. A medical photographer at the Birmingham University Medical School in England, Parker worked on a floor above a microbiology lab that was researching variola virus. Scientists suspect she contracted the disease by visiting the lab or through airborne virus that traveled through the building’s ventilation system. (4)

BIPOC and Smallpox

Much of smallpox’s spread was a result of colonization, with Europeans infecting Aboriginal people in Australia and New Zealand and Indigenous people in the Americas. Indeed, there is historical evidence that smallpox was sometimes used intentionally as a biological weapon against Black, Indigenous, and People of Color (BIPOC) populations.

In 1520, a Spanish ship sailing from Cuba, which was carrying an infected enslaved African, arrived in Mexico. Academics believe this marked the arrival of smallpox in the Americas. The disease began to circulate and rapidly wiped out an estimated 90 percent of Native Americans. European populations had gained increased immunity to the disease, thanks to repeated exposure, but Native Americans had no immune defense for the virus. (28,29,30)

In Australia, the first recorded major smallpox epidemic broke out in 1789. Most of the British colonists there had been exposed to smallpox as children and were unaffected, but the disease ravaged the Aboriginal community, killing up to 70 percent of that population. (31)

The slave trade also spread smallpox across Africa. Historians have traced smallpox infections to traders’ caravan routes. In 1713, after exposure to smallpox from Europeans, whole clans of Khoisan people died, making it easier for Europeans to wrest control of their land. (30)

Until 1977, smallpox outbreaks were still common in South America, Africa, and Asia. (4,30,32)

Related Conditions and Causes of Smallpox

The variola virus that causes smallpox belongs to the genus Orthopoxvirus. Other viruses in this genus that can cause diseases in humans are monkeypox and cowpox, spread by infected animals. (6)

Resources We Love

Centers for Disease Control and Prevention (CDC)

As the leading public health institute in the United States, the CDC works to protect citizens from threats like smallpox. Its website is a go-to resource for information about smallpox, including vaccines and bioterrorism risk.

Mayo Clinic

Based in Rochester, Minnesota, Mayo Clinic is a nonprofit dedicated to clinical practice, education, and research. Its website offers an overview of smallpox, including information on symptoms, diagnosis, and treatment.

MedlinePlus

MedlinePlus is part of the U.S. National Library of Medicine, the world’s largest biomedical library. The MedlinePlus homepage for smallpox has a brief introduction to the disease with links to other websites for details on symptoms and prevention. Another page on the website has a helpful explainer on smallpox.

National Institute of Allergy and Infectious Diseases (NIAID)

NIAID supports research — basic, preclinical, and clinical — to advance product development for biodefense and emerging infectious diseases, including new vaccines and treatments for smallpox. The NIAID website also delves into smallpox prevention and treatment.

World Health Organization (WHO)

Founded in 1948, the World Health Organization is a United Nations specialized agency focused on international public health. Its website delivers extensive information on smallpox, including the methods that resulted in the eradication of the disease and current efforts to prevent outbreaks.

CDC Emergency Preparedness and Response

This website provides information on diseases like smallpox, as well as natural disasters like tornadoes. The CDC has separate pages about potential smallpox bioterrorism and smallpox bioterrorism response planning.

U.S. Food and Drug Administration (FDA)

The FDA website collects news on smallpox and facts about the disease; information about the FDA’s role in smallpox emergency preparedness and response; basic info and links regarding smallpox vaccines, treatments, and diagnostic procedures; and emergency contact numbers.

Additional reporting by Shira Feder.

Editorial Sources and Fact-Checking

1. Smallpox. MedlinePlus. April 14, 2021.
2. What Is Smallpox? Centers for Disease Control and Prevention. June 7, 2016.
3. Berche P. Life and Death of Smallpox. Presse Medicale. September 2022.
4. History of Smallpox. Centers for Disease Control and Prevention. February 20, 2021.
5. Smallpox: Signs and Symptoms. Centers for Disease Control and Prevention. June 7, 2016.
6. McCollum AM. Travelers’ Health: Smallpox and Other Orthopoxvirus-Associated Infections. Centers for Disease Control and Prevention. December 7, 2022.
7. Smallpox. National Organization for Rare Disorders. April 7, 2009.
8. Tesini BL. Smallpox (Variola). Merck Manual. April 2023.
9. Smallpox. Cleveland Clinic. April 7, 2023.
10. Smallpox: Symptoms and Causes. Mayo Clinic. August 5, 2022.
11. Smallpox: Transmission. Centers for Disease Control and Prevention. June 7, 2016.
12. Smallpox: Diagnosis and Evaluation. Centers for Disease Control and Prevention. July 24, 2017.
13. Chickenpox (Varicella). Centers for Disease Control and Prevention. April 28, 2021.
14. Chickenpox and Smallpox Rash Comparison. MyHealth.Alberta.ca. February 9, 2022.
15. Smallpox: Frequently Asked Questions. Illinois Department of Public Health. December 18, 2002.
16. Deleted, February 10, 2023.
17. Smallpox: Diagnosis and Treatment. Mayo Clinic. August 5, 2022.
18. Tecovirimat. DrugBank Online. September 2, 2022.
19. Smallpox: Prevention and Treatment. Centers for Disease Control and Prevention. August 8, 2022.
20. Smallpox: Who Should Get Vaccination. Centers for Disease Control and Prevention. July 12, 2017.
21. Smallpox: Vaccine Basics. Centers for Disease Control and Prevention. August 8, 2022.
22. Smallpox. World Health Organization. June 28, 2016.
23. Smallpox: Side Effects of Smallpox Vaccination. Centers for Disease Control and Prevention. July 12, 2017
24. Clinical Features of Smallpox. Assessment of Future Scientific Needs for Live Variola Virus. 1999.
25. Smallpox: Bioterrorism Response Planning. Centers for Disease Control and Prevention. January 6, 2017.
26. Harris R. Smallpox Virus Found in Unsecured NIH Lab. NPR. July 8, 2014.
27. Babkin IV, Babkina IN. The Origin of the Variola Virus. Viruses. March 2015.
28. Pringle H. How Europeans Brought Sickness to the New World. Science. June 4, 2015.
29. Behbehani AM. The Smallpox Story: Life and Death of an Old Disease. Microbiology Reviews. December 1983.
30. Henderson DA. Smallpox: The Death of a Disease — The Inside Story of Eradicating a Worldwide Killer. 2009.
31. Smallpox Epidemic. National Museum of Australia. September 28, 2022.
32. Henderson DA. The Eradication of Smallpox — An Overview of the Past, Present, and Future. Vaccine. December 30, 2011.

Additional Sources

• Did Colonists Give Infected Blankets to Native Americans as Biological Warfare? History.com. November 25, 2019.
• Smallpox Vaccine Supply and Strength. National Institute of Allergy and Infectious Diseases. September 26, 2019.
• Smallpox Treatment. National Institute of Allergy and Infectious Diseases. December 30, 2014.
• Smallpox: Bioterrorism. Centers for Disease Control and Prevention. December 19, 2016.

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Monkeypox, monkeypox – mode of transmission, symptoms, diagnosis and prevention, risk groups – Moscow clinic It is clinically manifested by symptoms of intoxication, specific rashes on the skin.

The prognosis is always a concern, despite the fact that monkeypox is considered less lethal than smallpox. Nevertheless, it causes serious concern among doctors around the world.

What is known about monkeypox

Contrary to popular belief, this infection is not new. The virus was discovered in the middle of the 20th century in laboratory monkeys. After 20 years, it was first diagnosed in humans: in 1970 in the inhabitants of the Congo. Since that time, the infection has lived on the territory of the Democratic Republic, causing outbreaks, but has not provoked widespread fame and fear.

Only after the spread of the infection to the “civilized world”, the alarm was raised about the disease and, of course, measures to combat it, they spoke out loud.

Causes and mechanism of transmission of monkeypox

The description was made in the 1970s, during the first outbreak in the Congo. Since that time, outbreaks have been recorded in different regions of Africa. In 2003, a case was registered in a US resident.

Most often, the infection affects young and middle-aged people, but it is most dangerous in children and adolescents. This group has the highest percentage of deaths.

The mortality rate varies and ranges from 4-22%. And among the possible complications include damage to the organs of vision, the digestive tract, as well as sepsis.

The causative agent of monkeypox is a virus of the Poxviridae family, transmitted from infected animals through contact with body fluids.

Less commonly, infection occurs by eating meat from an infected animal that has not been sufficiently cooked. The virus can be transmitted from person to person, but subject to prolonged contact with blood, saliva and other body fluids.

The airborne route of infection is not excluded. Some sources of literature note the transplacental route of transmission, that is, from mother to child.

Risk factors for infection include:

• children’s age;
• reduced immunity;
• regular contact with exotic animals;
• poor hygiene.

The mechanism of the development of the disease is still poorly understood. It is believed that after the penetration of the virus, it accumulates in the lymph nodes, where it actively accumulates. At some point, the virus is released and spreads through the bloodstream to other tissues and organs.

Who is at risk:

• travelers from countries in Central or West Africa, parts of Europe where cases of monkeypox have been reported and confirmed in the month prior to symptom onset, monkeys.

Symptoms

The asymptomatic period is 7-20 days, but more often the first signs appear already 10-14 days after infection.

The onset of the disease is acute. Symptoms of intoxication come to the fore:

• fever over 38°C;
• headache;
• chills;
• weakness;
• muscle pain;
• lack of appetite.

Regional lymph nodes enlarge and become painful. Sometimes at the peak of the temperature increase, vomiting can form.

Characteristic rashes appear on the 3rd-4th day, when the body temperature drops slightly.

In 95% of cases, the rash first appears on the face, in 75% on the hands, and then spreads throughout the body.

The rash has several stages of development:

• a spot appears on the skin that differs from the color of the skin;
• then transforms into a tubercle;
• gradually fills with cloudy contents and a blister forms on the skin;
• after opening, crusts form, leaving scars behind.

At the stage when bubbles are formed, the temperature rises significantly, and other symptoms of intoxication are expressed.
The rash caused by monkeypox is easily confused with manifestations of other diseases, such as: secondary syphilis, herpes, chickenpox, shingles.

Diagnosis

You can already suspect the disease based on complaints and examination data. But to confirm it, you need:

• general and biochemical analysis of blood and urine;
• PCR test;
• bacterial seeding;
• enzyme immunoassay to help identify the pathogen.

Test systems have also been developed to detect the virus.

X-ray, examination of the abdominal organs and lymph nodes can be prescribed as additional methods.

If you suspect and have symptoms of monkeypox, contact your general practitioner .

Why is monkeypox dangerous? Most species of birds and animals have their own variety of poxviruses (poxviruses) that cause severe disease.

Of course, humanity was able to eradicate “species” smallpox, thanks to the general compulsory vaccination. At 19In 79, WHO declared the complete and final eradication of smallpox.

However, the spread of the monkeypox virus suggests that it will replace smallpox. So far, indeed, cases of transmission of infection between people are isolated, but everything can change.

Treating monkeypox

Patients should be hospitalized to reduce the chance of spreading the virus.

There is no specific treatment for monkeypox yet. Therefore, all treatment is symptomatic:

• body detoxification measures;
• painkillers;
• antipyretics;
• antiseptics are used for topical treatment of the skin;
• if there is a secondary infection, antibiotics may be given;
• doctors select a complex of drugs for the treatment of chronic diseases and other complications.

Vaccination

Monkeypox virus is a relative of smallpox and smallpox, belonging to the same family of viruses. And this allows us to conclude that the available smallpox vaccines are quite effective.

This is confirmed by the experts of the scientific center of virology and biotechnology “Vector”. The old vaccine protected against monkeypox by 85%, which is an excellent indicator.

However, smallpox vaccination has been discontinued in Russia since 1980, with the sole exception of people whose occupations and activities are associated with an increased risk of infection.

This means that all those born after the year 80 are not protected by . Experts are sure that the risk of importing a new virus into the territory of the Russian Federation is low, but they do not completely exclude such a scenario.

But in Russia there is a successful experience of mass vaccination against smallpox, although the same vaccine that leaves a mark on the shoulder is not used as unnecessary.

Prevention

The main condition for preventing outbreaks of infection is to stop the transmission of the virus from animals to humans, as well as to isolate infected people from contact with healthy people.
When traveling to countries where monkeypox is common, contact with animals that may carry the virus, especially rodents and primates, should be avoided.

If humans stop transmitting the infection from their natural habitat, monkeypox will naturally end in human society. However, each new case of infection causes the virus to mutate, and it is impossible to predict which mutations these will be.

Therefore, the danger of monkeypox should not be underestimated. Perhaps the mutations will be resistant to the action of the available vaccine.

is it necessary to be afraid of a new pandemic – Ministry of Health of the PMR

Monkeypox is a viral disease with symptoms similar to those of smallpox, but usually less severe. After the eradication of smallpox in 1980 and the subsequent cessation of the use of its vaccines, monkeypox became the most pathogenic for humans among orthopoxviruses.
The disease commonly occurs in Central and West Africa, mostly in close proximity to tropical rainforests, but the virus is increasingly found in urban areas.
Several animal species are susceptible to monkeypox virus, including striped squirrels, tree squirrels, Gambian rats, dormice and non-human primates.
According to WHO, the first case of human infection with monkeypox was reported in 1970 in a nine-year-old boy in the Congo, where smallpox was eradicated in 1968. over 1500 cases of monkeypox. The European Center for Disease Prevention and Control considers the risk of large scale spread of monkeypox to the general population to be low. There are confirmed cases in Romania, Poland and other European countries. On the territory of the Republic of Moldova and the PMR, as of June 14, no cases of suspected monkeypox were registered.
To date, the natural reservoir of the virus has not been identified, but rodents are the most likely to act.
One possible risk factor is the consumption of meat and offal from infected animals without proper heat treatment. People living in or near forested areas may be at some risk of contact with infected animals.
Transmission of infection from person to person is possible by airborne droplets and through close contact with skin lesions of an infected person (fluid from vesicles on the body, sores) or objects recently infected with viruses.
Because airborne transmission usually requires prolonged face-to-face contact, healthcare workers, households, and others who have had close physical contact with infected patients are at increased risk. It is possible that the virus can also be transmitted sexually.
The incubation period is usually six to thirteen days, but can vary from five to twenty-one days.
There are two periods of infection: the period of invasion (lasting 0-5 days), which is characterized by fever, severe headache, swollen lymph nodes, back pain, muscle pain and severe weakness; a period of skin rash that usually begins one to three days after a fever. Eruptions often concentrate on the face and limbs than on the trunk. They mainly affect the face (at 95% of cases), palms and soles of the feet (in 75%). In addition, the mucous membranes of the oral cavity (70%), genitals (30%), conjunctiva (20%), as well as the cornea of ​​​​the eyes are susceptible to rashes.
Eruptions go through several stages of development: a spot (a skin lesion with a flat base), then solid formations, later vesicles (filled with a clear and yellowish liquid), and then crusts that dry up and fall off. The number of skin lesions on the human body varies from single lesions to several thousand. In severe cases, the lesions may coalesce, which can cause large areas of skin to peel off.
In most cases, monkeypox is mild and symptoms disappear after two to four weeks. Severe illness usually occurs in children and is related to the duration of exposure to the virus, the health of the patient, and the nature of the complications. Patients with immunodeficiency are at risk of a more serious outcome of the disease. In the past, smallpox vaccination provided some degree of protection, today people younger than 40-50 years old (depending on the country) may be more susceptible to monkeypox due to the end of the worldwide smallpox vaccination campaign after the disease has been eradicated. Monkeypox complications include secondary infections, bronchopneumonia, blood poisoning, encephalitis, and corneal infection, which can lead to vision loss.
Avoid contact with rodents and primates due to the risk of monkeypox.
A sick person with suspected monkeypox is advised to remain in quarantine (21 days) until the rash has completely resolved and avoid contact with immunocompromised people and pets, and during this time refrain from physical contact with others.
During outbreaks of monkeypox in humans, close contact with an infected person is a major risk factor for infection. Health care workers and households of an infected person are most at risk of infection. Workers who have previously been vaccinated against smallpox should be selected for patient care.
Historically, a large number of infections have been caused by primary animal-to-human transmission. It is necessary to exclude unprotected contact with wild animals, including their meat, blood and offal.