Pathogens

Orthopoxvirus variola – Infection, Transmission & Diseases

Orthopoxvirus variola

The Orthopoxvirus variola virus is what causes smallpox , a dangerous infectious disease that has probably been around for thousands of years. The name smallpox means blister or pocket and refers to the skin lesions that are one of the most obvious symptoms of this disease.

Was ist Orthopoxvirus variola?

The human smallpox virus (Orthopoxvirus variola) was probably first detected around 1906 by the Mexican-German vaccinator Enrique Paschen. With the help of a light microscope , he succeeded in discovering the so-called elementary bodies in the lymph fluid of an infected child, which were named after him as Paschen’s bodies.

However, the ancient Egyptians already knew this disease. They called it Uhedu disease. In ancient China, at the time the Great Wall was built, people spoke of Hunpox and the ancient Romans called smallpox the Antonine plague.

In addition to smallpox (variola major or variola vera), there is also white smallpox (variola minor) and East African smallpox, also known as black pox. In addition to these human poxviruses, there are also various animal pox viruses such as monkeypox, cowpox and camelpox, which can also be transmitted to humans via the relevant intermediate hosts.

Occurrence, Distribution & Properties

In the past, smallpox has repeatedly caused devastating epidemics that have killed millions of people. They were considered one of the biblical plagues, raged in the Roman Empire for decades, wiped out parts of the natives of America, Africa and Australia and probably also came to Europe with the Crusaders. At that time, an estimated 400,000 people died here every year as a result of the disease. At times, the number of smallpox cases and fatalities even exceeded the numbers of plague – or cholera – deaths.

Famous historical figures such as Luis XV, King of France and Navarre or the Russian Tsar Peter II died from it. Beethoven was probably deaf from smallpox, and Josef Haydn’s face was disfigured by smallpox scars.

From the beginning of the 19th century there were smallpox vaccinations with live vaccines, which made it possible to quickly suppress smallpox. The number of new infections fell. In 1967 the World Health Organization (WHO) began a worldwide campaign to eradicate smallpox, compulsory vaccination was introduced and in 1980 the WHO determined that the smallpox virus can be considered practically extinct. As a result, general smallpox vaccinations were abolished. However, in many countries around the world (including Germany) there is still a stock of vaccines to prevent possible outbreaks of smallpox and for the early treatment of groups of people who may be at risk or who are infected.

Diseases & Ailments

The last recorded cases of smallpox were in Bangladesh in 1975, in Birmingham in 1978 and in Somalia. However, there are still research facilities in which smallpox viruses are stored, at least in the USA and Russia.

Since the abolition of smallpox vaccinations, the number of people who contract monkeypox (orthopoxvirus simiae) or cowpox (orthopoxvirus bovis), for example, has increased, especially in Africa. So far, these types of smallpox have not occurred in vaccinated people, since a so-called “cross-infection protection” is given. In addition, some researchers worry that animal smallpox species could also mutate over time, making human-to-human transmission more likely.

The human smallpox virus can theoretically be transmitted through droplet infection when coughing and sneezing , but also through inhaling dust from infected bedding, clothing, dishes or other objects with which the sick person has had contact. Laboratory accidents are also possible.

Monkeypox can be transmitted to humans when infected rodents, rats, or monkeys bite or scratch humans, or when humans eat the flesh of infected animals. Cowpox and camelpox are partly transmitted during milking.

The incubation period of the smallpox virus is 2 weeks on average. At the onset of the disease, there is a severe feeling of illness. Those affected have a high fever , chills , headaches and body aches , sore throats and swollen lymph nodes . The fever generally runs in two episodes, after the second fever episode there are the skin changes typical of smallpox. The pustules and skin blisters spread mainly on the face, neck, chest, groin region and feet.

When smallpox dry up and fall off after weeks, they often leave bumps or pockmarks on the skin. If the course of the disease is particularly severe, serious consequential damage such as paralysis , brain damage and blindness can also occur. But milder gradients also occur frequently. The risk of infection with smallpox is very high. The treatment options are limited to strict bed rest, antipyretics and painkillers , as well as the treatment of secondary diseases.

In the past, most people who contracted smallpox died. In the 20th century, the mortality rate was about 30 percent. The disease hits particularly hard patients with a weakened immune system , the elderly and children. In people infected with animal smallpox, the mortality rate is significantly lower, at around one percent. Anyone who survives smallpox is then resistant and thus protected from the disease for life.

 

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Hello! I am Lisa Newlon, and I am a medical writer and researcher with over 10 years of experience in the healthcare industry. I have a Master’s degree in Medicine, and my deep understanding of medical terminology, practices, and procedures has made me a trusted source of information in the medical world.