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How Does The Smallpox Vaccine Work

Key Facts About Vaccination

How do vaccines work? – Kelwalin Dhanasarnsombut
  • Smallpox vaccination is based on a thousand-year old technique called inoculation, in which a small sample of infected matter is deliberately introduced into the body in order to prevent the full disease from developing.

  • A vaccine stops you from getting an infectious disease by stimulating your body’s immune system to produce chemicals called antibodies that will combat a future infection.

  • The first vaccine was developed to protect against smallpox, a deadly disease that killed thousands of people until the 1800s. Thanks to vaccination, smallpox was completely eradicated in 1979.

  • An antitoxin is a blood-based product that ‘borrows’ immunity from another person or animal to help you fight an infection, once you already have it.

  • The sciences of microbiology and immunology have produced different vaccines and antitoxins to prevent and combat a range of infectious diseases.

For a long time people observed that you rarely get the same infectious disease twice, or if you do its usually much milder the second time round.

What if you could artificially expose a person to a safer form of the disease before they encountered a potentially lethal version of the full disease? That might prevent them getting the full-blown disease if they encountered it in the future. This is the basis of vaccination, which itself is based on the thousand-year-old practice of inoculation.

Vaccination has saved millions, mostly children, from many potentially fatal diseases.

Smallpox And The Story Of Vaccination

Published: 25 April 2019

You are reading in Smallpox and the story of vaccinationPart of Epidemics

Smallpox and vaccination are intimately connected. Edward Jenner developed the first vaccine to prevent smallpox infections, and this success led to the global eradication of smallpox and the development of many more life-saving vaccines.

Effective Herd Immunity Depends On Vaccination

Because immunity varies with age and not everyone can get vaccinated such as those who are immunocompromised, have specific allergies or pregnant women with certain types of vaccines herd immunity is a crucial protective phenomenon.

To establish it, one important factor is the number of immunized people within a population has to be at a certain percentage or threshold. According to the WHO, this figure was eight out of every 10 people for smallpox, based on its early eradication effort.

And because pathogens are not confined by geographical borders, this 80% immunization or higher is not a threshold restricted to one population it has to be shared by all, whether at a local, national or global level. This means if any populations have vaccination rates below the threshold, there is a great risk for disease transmission to other unvaccinated or vulnerable individuals, even in populations with adequate herd immunity, such as in the case with measles outbreaks in recent years.

For smallpox, this homogeneity in vaccination rates across varying populations was only successfully achieved with mass smallpox vaccination, as claimed by the Facebook post.

Routine smallpox vaccination in the U.S. was stopped in 1972, after it was declared eradicated. The CDC only recommends the vaccine to lab workers who work with smallpox or smallpox-like viruses, and to those who need long-term protection like military personnel.

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Getting The Smallpox Vaccine

The smallpox vaccine is given by a special technique. It is not administered as a shot in the way that most other vaccines are. It is given using a two-pronged needle that is dipped into the vaccine solution. When removed, the needle holds a droplet of the vaccine. The needle is used to prick the skin a number of times in a few seconds. The pricking is not deep, but it will cause a sore spot and one or two drops of blood to form. The vaccine usually is given in the upper arm.

If the vaccination is successful, a red and itchy lesion develops at the vaccine site in 3 to 4 days. In the first week, the lesion becomes a large blister, fills with pus, and begins to drain. During the second week, the lesion begins to dry and a scab forms. The scab falls off in the third week, leaving a small scar.

People who are being vaccinated for the first time have a stronger reaction than those who are being revaccinated. The following pictures show the progression of the site where the vaccine is given in someone who has not gotten the vaccine before.

Vaccine Risks Vs Monkeypox Disease

Will the COVID

For most persons who have been exposed to monkeypox, the risks from monkeypox disease are greater than the risks from the smallpox or monkeypox vaccine.

Monkeypox is a serious disease. It causes fever, headache, muscle aches, backache, swollen lymph nodes, a general feeling of discomfort, exhaustion, and severe rash. Studies of monkeypox in Central Africawhere people live in remote areas and are medically underservedshowed that the disease killed up to 11% of people infected.

In contrast, most people who get the smallpox or monkeypox vaccine have only minor reactions, like mild fever, tiredness, swollen glands, and redness and itching at the place where the vaccine is given. However, these vaccines do have more serious risks, too.

In certain groups of people, such as people with serious immune system problems, complications from ACAM2000 can be severe. If you have concerns about whether you should receive ACAM2000, talk to your healthcare provider. This vaccine has the potential for more side effects and adverse events than the newer vaccine, JYNNEOS.

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Cdc Warns Lgbtq Community At Higher Risk To Get Monkeypox

Officials from the Centers for Disease Control and Prevention said Monday that more than 1,000 doses of Jynneos are stockpiled and can be distributed to those who have been in contact with infected people. In total, the government has more than 100 million doses of another smallpox vaccine called ACAM2000, CDC officials said.

In addition, the FDA has also approved two therapeutics to treat smallpox, called TPOXX and Tembexa.

“The drugs that have been approved for smallpox have not yet been approved for monkeypox. But theres excellent data in the filings for the licensure of those drugs where theyve been tested against monkeypox in monkeys, and it works very well,” said Grant McFadden, the director of the Biodesign Center for Immunotherapy, Vaccines and Virotherapy at Arizona State University.

The national stockpile includes TPOXX doses, according to the FDA.

“Containing an outbreak of monkeypox should be far less challenging than Covid-19,” said Dr. Peter Hotez, the dean of the National School of Tropical Medicine at Baylor College of Medicine and a co-director of the Center for Vaccine Development at Texas Childrens Hospital. “We already have interventions.”

The Smallpox And Coronavirus Vaccines: 30 Facts From The Vaccine Vault

Members of the Association of French Models line up for their smallpox vaccinations, 2nd October … 1955.

Over the next several months, a Tales from the Vaccine Vault series will use lists of facts to sketch portraits of vaccine developers and their pitfalls and successes.

In telling tales about the smallpox vaccine, this list offers more than just a walk down memory lane for anyone old enough to remember smallpox terror. Together the facts tell a then and now story about how difficult it is to eradicate a disease, how vaccines work, and how devastating a virus left unchecked can be.

1. As horrific as Covid-19 is, its nowhere near as deadly as smallpox. With a fatality rate of 30%, smallpox decimated populations from the third century BC until 1977. Even though it was eradicated well before the 20th century was over, it killed roughly 500 million people in that century alone.

2. SARS-CoV-2 causes Covid-19. It is a more dangerous cousin of the SARS coronavirus that killed nearly 800 people in 2003 and 2004. The current fatality rate for COVID-19s coronavirus varies by country, from 0.2% in Germany to 7.7% in Italy. The World Health Organization estimates that Covid-19 has killed 1.324 million people so far.

4. This may be partly because SARS-CoV-2, like most viruses, has animal “reservoirs.” If public health efforts succeed at pushing it out of human populations, it will likely live on in fruit bats and ferret populations , only to return to infect humans again.

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Status Of Vaccine Deployment

Demand for monkeypox vaccines has been high in New York City. The few times the city has opened vaccine appointments, the slots were filled in mere minutes.

Federal health officials are holding weekly calls with leading health organizations that provide care to gay communities, according to Walensky. McFadden said these groups are robust and he is hopeful they will do a very good job of doling out vaccinations and care to those who need it.

If we can get the vaccine to everyone, chances are that this is a disease that can be stamped out, McFadden said.

The Department of Health and Human Services has made some 374,000 doses of the vaccine available to states and has so far distributed nearly 200,000 doses. Walensky said 780,000 more doses will soon be approved for release. About 7 million doses of the vaccine will be available in the U.S. by 2023.

Were not asking New Yorkor anybodyto hold back doses right now because were pretty confident that whats going to come in is going to be able to cover those second doses, Walensky said.

What To Know About The Monkeypox Virus

Chapter 2, Part B: Vaccine Administration

What is monkeypox?Monkeypox is a virus similar to smallpox, but symptoms are less severe. It was discovered in 1958, after outbreaks occurred in monkeys kept for research. The virus was primarily found in parts of Central and West Africa, but in recent weeks it has spread to dozens of countries and infected tens of thousands of people, overwhelmingly men who have sex with men. On July 23, the World Health Organization declared monkeypox a global health emergency.

What are the symptoms?People who get sick commonly experience a fever, headache, back and muscle aches, swollen lymph nodes, and exhaustion. A few days after getting a fever, most people also develop a rash that starts with flat red marks that become raised and filled with pus. On average, symptoms appear within six to 13 days of exposure, but can take up to three weeks.

How does it spread?The monkeypox virus can spread from person to person through close physical contact with infectious lesions or pustules, by touching items like clothing or bedding that previously touched the rash, or via the respiratory droplets produced by coughing or sneezing. Monkeypox can also be transmitted from mother to fetus via the placenta or through close contact during and after birth.

Dr. Slifka and other experts emphasized that while monkeypox can be severe and even fatal, the current outbreak is unlikely to swell into a large epidemic.

There are conflicting opinions on how long immunity from a smallpox vaccination lasts.

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Side Effects Of Mva Vaccine

The vaccine has a very good safety profile. Like all vaccines it can cause side effects, but most of these are mild and short-lived and not everyone gets them. Unlike the old smallpox vaccine, vaccination does not leave a scar.

Side effects may be more common in people who have previously received a dose of live smallpox vaccine. These people only need a single dose of MVA to boost their existing protection.

How Is Imvamune Different From The Old

Imvamune contains a weakened strain of the vaccinia virus, which provokes the immune response to fight off smallpox and monkeypox.

Unlike the original smallpox vaccine, this weakened virus is non-replicating, meaning it can’t make copies of itself.

Early-generation vaccines based on replicating vaccinia strains led to unpleasant side effects for some and could be problematic for people who were immunocompromised, said Dr. Zain Chagla, an infectious disease specialist at McMaster University in Hamilton.

In addition, older generations of smallpox vaccine are administered differently. Instead of a regular syringe, the health-care provider uses a “bifurcated needle” with two prongs and pricks the skin repeatedly to get the dose in.

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Receiving Vaccine After Exposure To Monkeypox Virus

The sooner an exposed person gets the vaccine, the better.

CDC recommends that the vaccine be given within 4 days from the date of exposure in order to prevent onset of the disease. If given between 414 days after the date of exposure, vaccination may reduce the symptoms of disease, but may not prevent the disease.

Smallpox and monkeypox vaccines are effective at protecting people against monkeypox when given before exposure to monkeypox. Experts also believe that vaccination after a monkeypox exposure may help prevent the disease or make it less severe.

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How vaccines work

Monkeypox is not known to linger in the air, and it is not transmitted during brief periods of shared airspace. Instead, the disease most often spreads through direct physical contact with an infected individual, or with their bodily fluids. Because sores may be inside the body, including the mouth, vagina or anus, sexual transmission is possible. The virus can also be spread by contact with items that have touched either the infectious rash or bodily fluids, such as linens or clothing.

An infected individual is contagious from the moment symptoms begin. Those who develop a rash or lesions can continue to spread the disease until the rash has healed completely and is covered by a fresh layer of skin.

Adults like yourself who received the smallpox vaccine during the nationwide program that was in effect from the late 1940s until 1972 are believed to have continuing immunity. This includes members of the U.S. military, who continued to receive smallpox vaccinations until 1991.

To combat this outbreak, the U.S. has just purchased 2.5 million doses of monkeypox vaccine, which bolsters the 500,000 doses already stockpiled. Distribution to high-risk individuals is expected to begin soon. You can find detailed information about smallpox and monkeypox at the CDC website. Visit and click the appropriate link.

Send questions to .

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Acip Recommendations For Pre

The Advisory Committee on Immunization Practices began serious discussions about the risks and benefits of pre-event smallpox vaccination in 2001. At that time, the committee concluded that the risks of vaccination outweighed the benefits in the current pre-event setting except for a very small number of individuals.11 The ACIP revisited this issue in June 2002 in light of the September 11, 2001 attacks, but continued to recommend against vaccination of the general population in the current pre-event setting of no confirmed smallpox. However, the ACIP did recommend vaccination for the following groups: persons pre-designated by the appropriate public health authorities to conduct investigation and follow-up of cases and selected personnel in facilities pre-designated to serve as referral centers to provide care for the initial cases of smallpox.

Monkeypox Vaccine: Whats Available In Australia And Who Should Get It

The WHO has declared the virus a global health emergency, while in Australia, monkeypox is now a communicable disease incident of national significance. Heres what we know about vaccination

On 28 July Australias chief medical officer Paul Kelly declared monkeypox a communicable disease incident of national significance. This means disease spread is serious enough that national policy, interventions and public messaging is needed to combat it, along with more resources.

It follows the World Health Organization declaring the spread of monkeypox a global health emergency earlier in July.

The US Centers for Disease Control and Prevention said there have been 20,311 monkeypox cases in 71 countries, including Australia, that have not seen monkeypox spread before. Heres what we know about the vaccines and who should get vaccinated in Australia.

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Current Vaccines Offer Protection Against Smallpox And Monkeypox

There are two different smallpox vaccines that the U.S. has in its stockpile that are either also approved or could be helpful against monkeypox: ACAM2000 and Jynneos. Both have been licensed by the U.S. Food and Drug Administration ACAM2000 in 2007 and Jynneos in 2019.

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Neither of those vaccines were the specific ones used when smallpox vaccination was mandatory during the 2oth century, according to Newman. But ACAM2000 replaces Dryvax, which was licensed by the FDA in 1931 and uses the same kind of virus to create an immune response.

The ACAM2000 vaccine doesn’t contain variola virus , but it does contain live vaccinia virus, which is in the poxvirus family and is related to variola virus. The vaccine is approved for those who are 18 and older and at high risk for orthopoxviruses , but can be used in people exposed to monkeypox, if needed.

The vaccine is different from typical vaccines in that it doesn’t include an injection. Instead, the vaccine is administered by a two-pronged needle dipped in vaccine solution that then pricks the upper arm. A small, red, itchy, sore spot develops at the vaccination site, which indicates a successful vaccination. The spot will then turn into a blister, then a scab, and leaves behind a scar.

What Monkeypox Vaccine Is Available In Canada

How we conquered the deadly smallpox virus – Simona Zompi

The vaccine approved for immunization against monkeypox in Canada is MVA-BN, or Modified Vaccinia Ankara – Bavarian Nordic. Bavarian Nordic, headquartered in Denmark, is the company that manufactures it.

In Canada, the vaccine has the trade name Imvamune.

Imvamune was originally authorized in Canada for “extraordinary use” against smallpox in November 2013, as part of the federal government’s emergency plan to immunize people if the deadly disease were ever to resurface. In 2020, Canada expanded the vaccine’s authorization to include immunization against monkeypox, NACI documents say.

Routine smallpox vaccinations stopped in Canada in the early 1970s. But because the viruses are related, those smallpox vaccinations may have provided some degree of immunity against monkeypox as well, experts say.

“It’s likely that this, you know, mass immunization campaign for smallpox really kept monkeypox in check for many years,” said Dr. Isaac Bogoch, an infectious diseases specialist at Toronto General Hospital.

But most people under 50 in Canada didn’t get that protection and that might be one of the reasons we’re seeing monkeypox now, he said.

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