All known smallpox viruses were finally eradicated in 1977 after a worldwide program by the World Health Organization was successful. However, it does still exist in laboratories in the United States and Russia and incidents of infection have occurred. There is the ever-present risk of deliberate infection of populations by biological warfare and it is believed that stocks are held by North Korea and Iran. A terrorist attack on a country could conceivably involve the release of a smallpox virus and, for this reason, sufficient vaccine is kept for the vaccination of everybody in the United States, should it ever be needed.
Smallpox is a viral disease, once common worldwide when it would sweep through countries leaving a trail of death. It is also known as variola, major or minor. Variola minor has a relatively mild effect and is not as serious as variola major, which can be a deadly disease. There exist two further forms of smallpox that were rare and almost inevitably fatal: a malignant form where lesions did not advance to the pustule stage, but remained flat on the skin and a haemorrhagic form where there was bleeding into the skin and the mucous membranes.
Approximately 30% of those infected with variola major would die and those who survived often lost their sight; most survivors would carry deep, disfiguring pocks on their skin, especially on the face. Children and young people were primarily the targets of the deadly infection.
There is an incubation period of 12-14 days during which time the person does not pass on the infection and feels quite normal. This is then followed by an abrupt change, a period of 2-3 days during which the patient may suspect that they are suffering from influenza, with some or all of the following symptoms:
*Feverishness with high body temperature
*Headache which can be severe
*Vomiting and/or diarrhoea
*General feeling of malaise
After this brief period of a few days, the temperature drops and the patient feels better. At this point the rash appears, characteristically flat spots on the face and the arms; only later will the rash be visible on the trunk. These lesions will also become evident in the nose and mouth of the patient, where they will quickly ulcerate. All the lesions progress simultaneously to pustules and about 12-14 days after the first appearance of symptoms, the pustules become scabs. When the scabs dry and fall off, they leave a deep depression [pock] that has lost pigmentation. Death, for those who will not recover from smallpox, occurs between the appearance of the rash and the appearance of the pustules.
Chickenpox is a common infection of childhood that used sometimes to be mistaken for smallpox though there are a number of differences. In chickenpox, lesions appear initially on the trunk rather than arms and face, they are not deeply set and appear to be at different stages of development; new lesions appear when there are already older, crusty scabs. In smallpox, all lesions appear and progress at the same time.
No effective treatment has ever been developed for smallpox, but a vaccine should be administered within a period of 1-4 days following exposure and before the appearance of the rash. This timely intervention may considerably reduce the severity of the infection and could possibly even prevent it. Once the rash has appeared, progress of the disease is inevitable and there can only be careful management of the symptoms as they occur.
There is no longer a program of vaccination against smallpox. The disease has been eradicated in the world, so exposure to it by the general public is extremely unlikely. The only people at risk of infection are laboratory workers where the virus is stored, or people who are in an area where the virus is deliberately released in a form of biological warfare. Research continues, nonetheless, into newer and more effective vaccines against this scourge of our forefathers vaccines that one hopes will never be needed.