What is smallpox?
Smallpox, or variola was a highly contagious and life-threatening viral disease that has plagued mankind for centuries. Thus, in the past three thousand years, one in ten people have died from the virus. Those who survived an epidemic, then possessed often enough defenses, but contact with new nations could then be disastrous, as was the case in America by the Colombian exchange.
The disease is caused by the smallpox virus. There are two types: the less dangerous Variola minor and non-ingeënten usually deadly Variola major. There are also several related animal viruses, in particular the Vaccinia virus, which causes vaccinia. Ranges of Vaccinia gives a man protection against smallpox. This one could by conscious infection with Vaccinia so protected; the term vaccination is derived from the Latin word vaca (cow).
Since the second half of the 1970s, the disease by an extensive global vaccination campaign no longer occurred. Smallpox was the first virus that has been eradicated by modern science, and also the only, until 14 October 2010 was declared the eradication of rinderpest.
This was only possible because:
- There is an effective vaccine exists;
- There is no symptomless carriers of the disease and
- There is no animal reservoir of the pathogen.
The genetic structure of the smallpox virus is now entirely known and turns out to be also scientifically very interesting when studying. The virus is still preserved in a few laboratories. The last known case of smallpox in the world occurred in England in september 1978, when Janet Parker, a photographer at the medical faculty of the University of Birmingham suffered the disease and died. There was at that time in that building a smallpox-research project going on, although the exact route of infection has never been cleared up. Only years before, in 1972, arose in Yugoslavia the last epidemic of smallpox in Europe.
Smallpox history
Smallpox epidemic came for and made large numbers of victims in waves in the middle ages and beyond. The disease was a leading cause of death, around 30% of infected people died out, including different monarchs. Joseph Stalin ran the disease in his youth also on and showed the scars that remained behind on photos wegtoucheren. George Washington, Abraham Lincoln and Emperor Kangxi of China have also had the disease. The disease was characterized by large numbers of high fever and blisters on the skin, which unlike chicken pox especially on the limbs were concentrated.
It could be said that the smallpox have significantly affected history. The Spaniards were able to so easily master making the Aztecs and Inca empires because the Spanish conquerors by smallpox were joined, making the Indian population, which had no resistance, was decimated. When Hernan Cortes landed on the Mexican Coast, he fought a rival army of conquistadors, in which an infected soldier was in. This soldier infected one of Cortes own soldiers. The soldier died when Cortes army had to fight away from Tenochtitlan, the Aztecs were infected but in the skirmishes. When the city fell a year later, had a huge epidemic occurred that had killed most of the population. The survivors were too weakened to defend themselves.
After the fall of Tenochtitlan in 1521, the virus shifted southward to the Inca Empire. The Inca Emperor Huayna Capac became infected and died of the disease, making a civil war between his sons Atahualpa and Huascar broke out. Meanwhile, spread the smallpox itself in record time via the advanced road network. By smallpox and the civil war were the Incas further weakened, so that could repeat the stunt of Francisco Pizarro Cortés to conquer the Inca Empire in 1533 with a tiny army.
Afterwards, the successor of the smallpox epidemics afflict indigenous people. 60 to 90% of the Inca population died of smallpox and entire areas were depopulated. By other diseases and secondary causes such as famine died a lot of the people who had survived smallpox. The virus also spread to North America where likewise huge hits fell. This allowed the Europeans are good despite their smaller numbers, but they had to enter though slaves from Africa to work on the plantations. This eventually led to the current u.s. population for the most part either of European, either of African origin.
Smallpox symptoms
As mentioned earlier, there are two types of variola major, variola minor and smallpox viruses. Of this latter form also exist several variants. In most cases it will go as follows: disease progression after infection the virus will migrate to the lymph nodes via the respiratory organs and multiply. In this initial phase the virus will invade the cells, then after approx. 12 days lysis takes place: the infected cells go massively tegronde. In addition the virus released into the blood and will a second time in the bone marrow, spleen and lymph nodes multiply. Around this time the infected person will get sick. The first symptoms are those of a heavy flu: muscle and joint pain, fatigue and high fever (at least 38.5 degrees), nausea and vomiting. The patient is in this initial phase of the disease besmettelijkst.
After this phase, the virus attacks the skin cells, and rash, which occurs around day 12-15 on the forehead begins and the subsequent 24-36 hours the whole body covered. Often this comes with a temporary reduction of fever and a revival of the patient. In a normal variola major-case, the rash develop into blisters that are filled with a murky pusachtige liquid. However, this is not a real pus, but destroyed skin tissue. The vesicles feel firm to the touch and are somewhat elevated compared to the skin. Sometimes they contain a central slump that what appears on a small naveltje. In this phase the fever rises again and often the patient will feel sicker itself again.
The blisters will during the second illness week lose its charge and dry out, which scabs left behind. These crusts will lose weight and leave scars. The patient is from that moment no longer contagious and often also symptom free.
Variants and mortality
Variola minor
Variola minor is caused by a virus related to variola major. Disease progression is, however, significantly milder. The fever is lower and mortality is less than 1%. The disease came less common than variola major.
Variola major-normal type
The mortality of the normal type is around 10%.
Sometimes grow the vesicles in such a way that they come into contact with each other and to larger paste merge, where large pieces of epidermis of the DermIS are separated. The patient continues to feel sick longer, even after the disappearance of the rash. The risk of dying is much larger (to around 60%). If large pieces of skin are destroyed, this should be treated in the same manner as is necessary with second-degree burns.
Variola major-modified type
Modified variola major occurs when an already vaccinated person gets infected. Although this person is sick, but disease progression is much milder. The fever is lower and the rash less fierce. This variant was sometimes confused with chicken pox or another innocent infection, what could be a fatal mistake. Not for the patient himself (this type was rarely fatal), but for any ongevaccineerden in his environment.
Variola major-haemorrhagic type
Sometimes, in around 2% of the cases, developed a patient the hemorrhagic form of variola major. In that case there arise no blisters, but internal bleeding on the inside of the skin. The skin will thereby black discoloration, what this type the nickname ' black smallpox ' has delivered. Also several other organs, in particular the internal bleeding will show in the spleen, kidneys and muscles. Also the epicardium, the testes, liver and bladder may be affected. The patient will have a shortage of platelets and globulin develop, Thrombin. Around the fifth to the seventh day of the disease the patient will usually sudden death. Thrombocytopenia can occur at a later stage, but most patients don't even pick up this phase and are already died. The hemorrhagic form has a mortality rate of almost 100%: it is thus almost always fatal.
Complications
Sometimes an attack of smallpox led to complications. Usually these were respiratory tract infections such as bronchitis or pneumonia. In some cases hit the skin infected. In these cases, without prejudice to the fever remained high. Another described complication is encephalitis. When vesicles on the eye formed this could lead to blindness. Of course, almost always let the blisters disfiguring scars behind.
Smallpox treatment
Treatment of smallpox was mostly supportive, there existed no real cure for smallpox. The only real treatment preventive vaccination against smallpox was. However, in many cases led to vaccination side effects, which in some cases even fatal ended. Of course, this often weighed against the even greater risks to actually get the disease.