Pox virus - Dr. S. Sivasankara Narayani

1. 17CY312 – MEDICAL
MICROBIOLOGY (UNIT –II)
Dr. S. SIVASANKARA NARAYANI
ASSISTANT PROFESSOR
DEPARTMENT OF MICROBIOLOGY
AYYA NADAR JANAKI AMMAL COLLEGE
SIVAKASI
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Pox Virus (HIV)

2. POXVIRUS
• Smallpox is a contagious, disfiguring and often deadly disease that has affected humans for thousands of years.
• Naturally occurring smallpox was eradicated worldwide by 1980 — the result of an unprecedented global immunization
campaign.
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3. POXVIRUS
• Before smallpox was eradicated, it was a serious infectious disease caused by the variola virus. It was contagious—meaning, it spread from one person to
another. People who had smallpox had a fever and a distinctive, progressive skin rash.
• Most people with smallpox recovered, but about 3 out of every 10 people with the disease died. Many smallpox survivors have permanent scars over large areas
of their body, especially their faces. Some are left blind.
• Thanks to the success of vaccination, smallpox was eradicated, and no cases of naturally occurring smallpox have happened since 1977. The last natural
outbreak of smallpox in the United States occurred in 1949
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4. ADENOVIRUS
• 6th Century – Increased trade with China and Korea introduces smallpox into Japan.
• 7th Century – Arab expansion spreads smallpox into northern Africa, Spain, and Portugal.
• 11th Century – Crusades further spread smallpox in Europe.
• 15th Century – Portuguese occupation introduces smallpox into part of western Africa.
• 16th Century – European colonization and the African slave trade import smallpox into the
Caribbean and Central and South America.
• 17th Century – European colonization imports smallpox into North America.
• 18th Century – Exploration by Great Britain introduces smallpox into Australia.
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9. SYMPTOMS
• he first symptoms of smallpox usually appear 10 to 14 days after you're infected. During the
incubation period of seven to 17 days, you look and feel healthy and can't infect others.
• Following the incubation period, a sudden onset of flu-like signs and symptoms occurs. These include:
• Fever
• Overall discomfort
• Headache
• Severe fatigue
• Severe back pain
• Vomiting, possibly
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10. CAUSES
• Smallpox is caused by infection with the variola virus. The virus can be transmitted:
• Directly from person to person. Direct transmission of the virus requires fairly prolonged face-to-
face contact. The virus can be transmitted through the air by droplets that escape when an infected
person coughs, sneezes or talks.
• Indirectly from an infected person. In rare instances, airborne virus can spread farther, possibly
through the ventilation system in a building, infecting people in other rooms or on other floors.
• Via contaminated items. Smallpox can also spread through contact with contaminated clothing and
bedding, although the risk of infection from these sources is less common.
• As a terrorist weapon, potentially. A deliberate release of smallpox is a remote threat. However,
because any release of the virus could spread the disease quickly, government officials have taken
numerous precautions to protect against this possibility, such as stockpiling smallpox vaccine
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11. DIAGNOSIS
• Antigenic structure
• Cultivation – chick embryo, tissue culture, animals
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12. TREATMENT
• Treatment of smallpox patients generally involves supportive
care. Vaccination with replication-competent smallpox vaccines (i.e., ACAM2000
and APSV) can prevent or lessen the severity of disease if given within 2 to 3
days of the initial exposure.
• Antiviral drugs – Tecovirimat, cidofovir , brincidofovir
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13. REFERENCE
• Textbook of Microbiology – Ananthanarayan and Paniker’s – 8th Edition,
2009
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sivasan91@gmail.com

14. QUESTIONS TO THINK
• Types of poxovirus
• Types of orthopoxvirus disease
• Name the special effects and type of genetic material in pox virus?
• mechanism of poxvirus infection
• Name the immunomodulators and regulators of poxviral infection?
• Which virus was used as the small pox vaccine?
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