Smallpox protective immunity

Although personnel who have been vaccinated recently and who have a demonstrated immune response should be fully protected against infection with smallpox virus, they should continue to observe standard contact precautions including using protective clothing and shoe covers when in contact with smallpox patients or contaminated materials to prevent inadvertent spread of variola virus to susceptible persons and potential self-contact with other infectious agents. 

No. Routine vaccination against smallpox ended in 1972. The level of immunity, if any among persons who were vaccinated before 1972 is uncertain therefore, these persons are assumed to be susceptible. For those were vaccinated, it is not known how long immunity lasts. Most estimates suggest that vaccination protection lasts from 3 to 5 years. Immunity can be boosted effectively with a single revaccination. Prior infection with the disease grants lifelong immunity. 

If people got the vaccination when it was available in the past, will they be immune Not necessarily. It is not clear how long protection from smallpox vaccine lasts. Most experts believe that protection from vaccination lasts 3 to 5 years. Persons who were vaccinated before 1972 may have some protection against smallpox, but it is uncertain. This means that the U.S. population has partial immunity at best. Immunity can be boosted with a single revaccination. Routine vaccination against smallpox ended in 1972. 

If someone had smallpox once, are they immune Would they need the vaccine Most people who have had smallpox disease are protected from the disease for life and do not need to be vaccinated. However, few people living in the United States have had smallpox. 

Treatment — Vaccinia immune globulin must be used in conjunction with a vaccinia vaccine if exposure to a smallpox case occurred more than 4 days earlier. However, only the vaccinia vaccine is required less than 4 days after such contact. The vaccine starts to be protective in approximately 7 days. This vaccine does not provide life-long immunity. Revaccination is recommended at 5- to 10-year intervals. Certain antiviral drugs such as Cidofovir have demonstrated that they confer some protection against infection. Unfortunately, because smallpox has been eradicated, limited research on such drugs has been conducted.3... 

The word vaccination comes from vaccinia, the name of the virus now known to cause cowpox vaca is the Latin word for cow ). The term vaccination is now broadly used to describe the process of causing a mild disease in order to protect a person from a more dangerous disease. Vaccination is one form of immunization, exposing the body to a material to stimulate a protective response from the immune system. Vaccination is routinely used to prevent many illnesses, including measles, rnmnps, German measles (rubella), chicken pox, and polio. Many of these illnesses have disappeared or become very rare in developed countries that provide widespread vaccinations. Smallpox has been eradicated worldwide, thanks to... 

In 1798 Edward Tenner published the classc memoir, An Inquiry into the Causes and Effect of the Variolae Vacciniae, documenting how inoculation with cowpox protected humans against smallpox infection [1]. Louis Pasteur s formulation of the germ theory extended the understanding of this kind of protection against infection [1,2]. About 100 years later, isolation of the diphtheria bacihus and description of a protective substance (antitoxin) by Roux and Yersin demonstrated that the protective substance found in the serum of immunized animals can be transferred to susceptible animals and thereby confer passive immunity [4]. The antitoxin or... 

For many years the preferred approach to immunity to infectious disease lias been by development of active immunity through the injection of a vaccine. The vaccine may be either an attenuated live infections agent, or an inactivated or killed product. In either case, protective substances called antibodies are generated in the bloodstream these, are described in the next section. Vaccines for a number of diseases have been available for many years and have assisted in the eradication of some diseases, such as smallpox. As new strains of bacteria and viruses are discovered, additional vaccines becomes available from time to time. See also Vaccine Technology,... 

The existence of an immune system in mammals, highly effective in protecting against disease after recovery from an initial infection, also has not prevented periodic catastrophic epidemics and epizootics. However, an astute English country doctor, Edward Jenner, noted immunological cross protection against deadly smallpox in English milkmaids who had recovered from mild cowpox. Despite skepticism, ridicule and even hostility of many of his peers, Jenner developed vaccination as one of the safest and most effective mammalian disease preventive measures known. We hope and believe that the same can be accomplished for plants. 

Smallpox is a deadly disease that has plagued humanity for hundreds of years. In most outbreaks, children were most often infected because adults were protected by immunity from vaccine-induced or previous smallpox infection (Henderson et al., 1999). Large outbreaks in schools were uncommon because the smallpox virus is not transmitted until the rash appears by this time, infected children were confined to bed because of their symptoms (Henderson, 1999). 

Vaccination against infectious illnesses provides unseen protection against contagious diseases—afflictions causing permanent disability or even death. Vaccines have been responsible for dramatic decreases in morbidity and mortality secondary to infectious disease, and in the case of smallpox, has globally eradicated a once life-threatening illness.However, while true adverse consequences of vaccination have never exceeded the level of adverse consequences of infection in the absence of vaccination, the public perception of harm secondary to vaccine administration has threatened to overshadow the victory of disease prevention.With the inception and continued evolution of immunization, the number of individuals protected against diseases has steadily increased. Unfortunately, the number of vaccine-related adverse events has also increased proportionally to vac-... 

D. Vaccine/Prophylaxis. Smallpox vaccine (vaccinia virus) is a licensed live poxvirus vaccine that induces strong cross-protection against smallpox. Reliable data are sparse as to efficacy and durability of protection. The duration vaccinia induced immunity is at least 3 years. Vaccine immunity may prevent or modify illness. Fully immune individuals exposed to the virus by the respiratory route may develop fever, sore throat, and conjunctivitis ("contact fever") lasting several days. The vaccine is administered by dermal scarification or intradermal jet injection. The appearance of a vesicle or pustule within several days indicates that the vaccine will be effective. Other available countermeasures include the postexposure use of Vaccinia immune globulin or primary vaccination within 3-4 days of exposure yields some protection. 

Individuals who were vaccinated during the WHO smallpox eradication campaign in the 1970s were considered to have immunity to smallpox for at least 3 years, but protection diminishes over time. The only vaccine still available in the United States is a live vaccinia virus manufactured by Wyeth-Ayerst Laboratories (now Wyeth-Lederle Vaccines and Pediatrics, and no longer manufacturing the vaccinia vaccine). The CDC... 

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