Smallpox is not known to be transmitted by insects or animals. A person with smallpox is sometimes contagious with onset of fever prodrome phase , but the person becomes most contagious with the onset of rash.
Patients remain infectious until the last scab falls off. Smallpox can be prevented through use of the smallpox vaccine, even if the vaccine is given within three days after exposure to smallpox. There is no proven treatment for smallpox, but research to evaluate new antiviral agents is ongoing. Preliminary results with the drug, cidofovir suggest it may be useful. The use of cidofovir to treat smallpox or smallpox vaccine reactions should be evaluated and monitored by experts at NIH and CDC.
Patients with smallpox can benefit from supportive therapy e. The smallpox vaccine is the only way to prevent smallpox. The vaccine is made from a virus called vaccinia, which is another pox-type virus related to smallpox.
The vaccine helps the body develop immunity to smallpox. It was successfully used to eradicate smallpox from the human population. Routine vaccination of the American public against smallpox stopped in after the disease was eradicated in the United States. Until recently, the U. After the events of September and October, , however, we have taken extensive actions to improve our level of preparedness against terrorism. For smallpox, this included updating a response plan and ordering enough smallpox vaccine to immunize the American public in the event of a smallpox outbreak.
The plans are in place, and there is sufficient vaccine available to immunize everyone who might need it in the event of an emergency. The smallpox vaccine is not available to the general public at this time. If vaccination is considered advisable, you will be notified quickly. The smallpox vaccine is not given with a hypodermic needle. It is not a shot, like many vaccinations.
The vaccine is given using a bifurcated two-pronged needle that is dipped into the vaccine solution. When removed, the needle retains a droplet of the vaccine.
The needle is then used to prick the skin 15 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 bump develops at the vaccination site in three or four days.
In the first week after vaccination, the bump becomes a large blister, fills with pus, and begins to drain. During week two, the blister begins to dry up 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. Vaccination within 3 days of exposure will completely prevent or significantly modify smallpox in the vast majority of persons. Vaccination 4 to 7 days after exposure likely offers some protection from disease or may modify the severity of disease.
Past experience indicates that the first dose of the vaccine offers protection from smallpox for 3 to 5 years, with decreasing immunity thereafter. If a person is vaccinated again later, immunity lasts longer. Recent tests have indicated that diluted smallpox vaccine is just as effective in providing immunity as full-strength vaccine. The vaccine is made from a virus called vaccinia, another pox-type virus related to smallpox.
The smallpox vaccine helps the body develop immunity to smallpox. The smallpox vaccine does not contain smallpox virus and cannot spread or cause smallpox. However, the vaccine does contain another virus called vaccinia which is live in the vaccine. Because the virus is alive, it can spread to other parts of the body or to other people from the vaccine site. For that reason, the vaccine site must be carefully monitored.
Vaccinia is spread by touching a vaccination site before it has healed or by touching bandages or clothing that have become contaminated with live virus from the vaccination site. Vaccinia is not spread through airborne contagion. The vaccinia virus may cause rash, fever, and head and body aches. Vaccinia is not spread through the air. At some point in the s, the virus used to make the smallpox vaccine changed from cowpox to vaccinia virus.
Traces of smallpox pustules found on the head of the year-old mummy of the Pharaoh Ramses V. Download pdf icon [PDF — 1 page]. Unfortunately, this global eradication campaign suffered from a lack of funds, personnel, and commitment from countries, and a shortage of vaccine donations. Despite their best efforts, smallpox was still widespread in , causing regular outbreaks across South America, Africa, and Asia.
The Intensified Eradication Program began in with a promise of renewed efforts. Laboratories in many countries where smallpox occurred regularly were able to produce more, higher-quality freeze-dried vaccine. Other factors that played an important role in the success of the intensified efforts included the development of the bifurcated needle, the establishment of a case surveillance system, and mass vaccination campaigns.
By the time the Intensified Eradication Program began in , smallpox was already eliminated in North America and Europe Cases were still occurring in South America, Asia, and Africa smallpox was never widespread in Australia. The Program made steady progress toward ridding the world of this disease, and by smallpox was eradicated from South America, followed by Asia , and finally Africa In late , three-year-old Rahima Banu from Bangladesh was the last person in the world to have naturally acquired variola major.
She was also the last person in Asia to have active smallpox. She was isolated at home with house guards posted 24 hours a day until she was no longer infectious. A house-to-house vaccination campaign within a 1. A member of the Smallpox Eradication Program team visited every house, public meeting area, school, and healer within 5 miles to ensure the illness did not spread. They also offered a reward to anyone who reported a smallpox case.
Ali Maow Maalin was the last person to have naturally acquired smallpox caused by variola minor. Maalin was a hospital cook in Merca, Somalia. On October 12, , he rode with two smallpox patients in a vehicle from the hospital to the local smallpox office. On October 22, he developed a fever. At first healthcare workers diagnosed him with malaria, and then chickenpox.
The smallpox eradication staff then correctly diagnosed him with smallpox on October Maalin was isolated and made a full recovery. Maalin died of malaria on July 22, , while working in the polio eradication campaign. Janet Parker was the last person to die of smallpox. However, the disease continued to infect and kill people on a widespread basis for another years. The last known natural case occurred in in Somalia. By , the WHO declared that smallpox had been completely eradicated, although government and health agencies still have stashes of smallpox virus for research purposes.
People no longer receive routine smallpox vaccinations. The smallpox vaccine can have potentially fatal side effects, so only the people who are at high risk of exposure get the vaccine.
Historical accounts show that when someone was infected with the smallpox virus, they had no symptoms for between seven and 17 days. However, once the incubation period or virus development phase was over, the following flu-like symptoms occurred:.
These symptoms would go away within two to three days. Then the patient would feel better. However, just as the patient started to feel better, a rash would appear. The rash started on the face and then spread to the hands, forearms, and the main part of the body. The person would be highly contagious until the rash disappeared.
Within two days of appearance, the rash would develop into abscesses that filled with fluid and pus. The abscesses would break open and scab over. The scabs would eventually fall off, leaving pit mark scars. Until the scabs fell off, the person remained contagious. There were two common and two rare forms of smallpox. The two common forms were known as variola minor and variola major.
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