ACAM2000 is a

smallpox vaccine The smallpox vaccine is the first vaccine to be developed against a contagious disease. In 1796, British physician Edward Jenner demonstrated that an infection with the relatively mild cowpox virus conferred immunity against the deadly smallpox ...

manufactured by

Sanofi Pasteur Sanofi Pasteur is the vaccines division of the French multinational pharmaceutical company Sanofi. Sanofi Pasteur is the largest company in the world devoted entirely to vaccines. It is one of four global producers of the yellow fever vaccine. ...

Biologics Co. The vaccine provides protection against

smallpox Smallpox was an infectious disease caused by variola virus (often called smallpox virus) which belongs to the genus Orthopoxvirus. The last naturally occurring case was diagnosed in October 1977, and the World Health Organization (WHO) c ...

for people determined to be at high risk for smallpox infection.

Background

Smallpox Smallpox was an infectious disease caused by variola virus (often called smallpox virus) which belongs to the genus Orthopoxvirus. The last naturally occurring case was diagnosed in October 1977, and the World Health Organization (WHO) c ...

is considered a biological threat.

Biological agent A biological agent (also called bio-agent, biological threat agent, biological warfare agent, biological weapon, or bioweapon) is a bacterium, virus, protozoan, parasite, fungus, or toxin that can be used purposefully as a weapon in bioterroris ...

s are toxins or organisms that can cause illness or death in humans, animals and plants. Exposure can come from an intentional biological

terrorist attack Terrorism, in its broadest sense, is the use of criminal violence to provoke a state of terror or fear, mostly with the intention to achieve political or religious aims. The term is used in this regard primarily to refer to intentional violen ...

, accidental release of the agent, or a natural accident. Smallpox was eradicated in 1980. However, there has been interest in the development of vaccines due to the possible use of smallpox as a bioweapon.

Smallpox vaccine development

Smallpox vaccine development is now in its second generation. First-generation vaccines were derived from calf-lymph, and include Dryvax, APVS, Lancy-vaxina and Lister. Second-generation vaccines are cell-cultured and include ACAM2000 and CCSV. Both Dryvax and ACAM2000 come from the New York City Board of Health strain of vaccinia. Dryvax was grown on calf skin and then freeze-dried for storage. Dryvax was first licensed by the FDA in 1931; however, it is no longer manufactured. ACAM2000 is a second generation smallpox vaccine. It comes from a clone of Dryvax which is purified and produced using modern cell culture technology.

ACAM2000 history

Emergent BioSolutions developed ACAM2000 under a contract with the U.S.

Centers for Disease Control and Prevention The Centers for Disease Control and Prevention (CDC) is the national public health agency of the United States. It is a United States federal agency, under the Department of Health and Human Services, and is headquartered in Atlanta, Georgi ...

(CDC). The U.S.

Food and Drug Administration The United States Food and Drug Administration (FDA or US FDA) is a List of United States federal agencies, federal agency of the United States Department of Health and Human Services, Department of Health and Human Services. The FDA is respon ...

(FDA) approved ACAM2000 in August 2007. By February 2008, it replaced Dryvax for all smallpox vaccinations. As of 2010, there were over 200 million doses manufactured for the U.S.

Strategic National Stockpile The Strategic National Stockpile (SNS), originally called the National Pharmaceutical Stockpile (NPS), is the United States' national repository of antibiotics, vaccines, chemical antidotes, antitoxins, and other critical medical supplies. Its w ...

. According to the U.S. FDA, "The approval and availability of this second-generation smallpox vaccine in the Strategic National Stockpile (SNS) enhances the emergency preparedness of the United States against the use of smallpox as a dangerous

biological weapon A biological agent (also called bio-agent, biological threat agent, biological warfare agent, biological weapon, or bioweapon) is a bacterium, virus, protozoan, parasite, fungus, or toxin that can be used purposefully as a weapon in bioterroris ...

Administration of ACAM2000

The ACAM2000 vaccine is produced from the Vaccina virus. Vaccinia is closely related to smallpox. The ACAM2000 vaccine cannot cause smallpox because it does not contain the smallpox virus. Other vaccines containing live viruses include

measles Measles is a highly contagious infectious disease caused by measles virus. Symptoms usually develop 10–12 days after exposure to an infected person and last 7–10 days. Initial symptoms typically include fever, often greater than , cough, ...

mumps MUMPS ("Massachusetts General Hospital Utility Multi-Programming System"), or M, is an imperative, high-level programming language with an integrated transaction processing key–value database. It was originally developed at Massachusetts Gener ...

rubella Rubella, also known as German measles or three-day measles, is an infection caused by the rubella virus. This disease is often mild, with half of people not realizing that they are infected. A rash may start around two weeks after exposure and ...

polio Poliomyelitis, commonly shortened to polio, is an infectious disease caused by the poliovirus. Approximately 70% of cases are asymptomatic; mild symptoms which can occur include sore throat and fever; in a proportion of cases more severe s ...

and

chickenpox Chickenpox, also known as varicella, is a highly contagious disease caused by the initial infection with varicella zoster virus (VZV). The disease results in a characteristic skin rash that forms small, itchy blisters, which eventually scab ...

. The vaccine is administered using a

bifurcated Bifurcation or bifurcated may refer to: Science and technology * Bifurcation theory, the study of sudden changes in dynamical systems ** Bifurcation, of an incompressible flow, modeled by squeeze mapping the fluid flow * River bifurcation, the for ...

stainless steel needle rather than a syringe. The needle is dipped into the vaccine solution and used to prick the skin several times in the upper arm. The vaccinia virus will begin to grow at the injection site. It will cause a localized infection, with a red itchy sore produced at the vaccination site within three to four days. If the infection occurs, that is an indication that the vaccine was successful. Ultimately, the sore turns into a blister and then dries up. A scab forms and then falls off in the third week, leaving a small scar behind.

Risks

Administration of ACAM2000 can pose risks and cause side effects. Most people who have taken the vaccine report normal, usually mild reactions. These reactions include a sore arm, fever, and body aches. Some people may have side effects ranging from serious to life-threatening. According to the FDA-approved prescribing information leaflet, "Common adverse events include inoculation site signs and symptoms, lymphadenitis, and constitutional symptoms, such as malaise, fatigue, fever, myalgia, and headache." These reactions are less frequent in people being revaccinated than those receiving the vaccine for the first time. As far as pregnancy goes, it is recommended that the vaccine should be given to pregnant women who have been exposed to smallpox. No contraindications exist to receiving the vaccine in case of an outbreak emergency. "Because the risk of maternal serious illness or death, prematurity, miscarriage, or stillbirth from a smallpox infection are greater than the risk of the vaccination, smallpox vaccine is recommended and should be offered to pregnant women in case of an outbreak emergency."

References

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External links

ACAM2000 prescribing information
Healthcare in the United States History of immunology Infectious diseases

Vaccine A vaccine is a biological Dosage form, preparation that provides active acquired immunity to a particular infectious disease, infectious or cancer, malignant disease. The safety and effectiveness of vaccines has been widely studied and verifie ...

Smallpox vaccines Vaccines