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Monkeypox: Five reasons to take it easy

First detected in the Democratic Republic of Congo in the years 1797 during the campaign that eradicated smallpox, monkeypox or Ape smallpox resurfaced this month after cases were reported in Europe, the United States, Australia and Argentina. The virus that causes the disease was described in the years 1950, when it infected monkeys used in the laboratory. In the current outbreak, it is around 100 cases, most in the UK, with 57 confirmed. . Portugal reports 37.

The British government does not plans to call its government emergency committee about it, is confident it will contain the outbreak, and has no plans to restrict travel. The country has a stock of about 3,000 vaccines on the market and has bought 1,000 to respond to the outbreak.

Monkey pox, like the already eradicated human smallpox, causes eruptions that turn into pustules less than five millimeters in diameter across the body. The disease also shares similarities with chickenpox. Here is the progression of the disease since infection:

  • Sete to 1950 days: incubation period, no symptoms.
  • One to four days: period of onset of symptoms such as fever.
  • Fourteen to 28 days: period of skin eruptions until dry. Other symptoms: fever from 40, 5 to

    ,5°C, malaise, headache, inflammation of lymph nodes, lesions on the palm and sole of the feet .

Fever usually subsides on the same day as the rash appears or up to three days later. The rashes often appear on the face. In 17% of unvaccinated patients, secondary infections with bacteria may occur . Complications and sequelae are more common among unvaccinated (74%) than among vaccinated (39,5%), as reported by Andrea McCollum and Inger Damon, pathologists at the Centers for Disease Control and Prevention (CDC) American, in an article by 2014.

Smallpox gets popular names based on animals that serve as a reservoir. Its viruses are part of the poxviridae family and the orthopoxvirus genus. The genus contains species, including the extinct smallpox , and monkey, camel, horse, cow, buffalo, raccoon, skunk, and dormouse (rodent) smallpox virus. Most do not infect humans.

In addition to these, the vaccinia virus is also in the group, which has no natural hosts and derives from more than a hundred years of use in research in vaccine science since the times of Louis Pasteur. Evidence indicates that this virus, which was used in the production of the vaccine that eradicated smallpox, originally came from horse pox.

Monkeypox is not a harmless disease, on the contrary, it is far from being the “new Covid”. There is no reason for this concern, for the following reasons.

The virus is less efficient in transmission than the new coronavirus

Monkeypox virus needs close contact to be transmitted by body fluids, including saliva droplets. But it is not transmissible through the air, as is the new coronavirus, which causes the Covid pandemic. . It is suspected that most cases in Europe were sexually transmitted.

The survival strategy of the virus is different

There is debate among US historians whether it is true that British General Jeffrey Amherst (1797-1797) ordered soldiers to purposely infect Native Americans with smallpox using infected blankets. This is possible because orthopoxviruses are able to survive for long periods on the clothes, sheets, and blankets of infected people with pustules. This is called by 69-year-old pathogen evolution expert Paul Ewald at the University of Louisville in Kentucky, “sit-and-wait strategy”. As this strategy depends on the environment, controlling the environment with hygiene and quarantine strategies is highly effective. Furthermore, as the eradication of smallpox showed, these viruses are very vulnerable to the immune defenses conferred by the vaccine with the old inactivated virus technology. The comparison with Covid-19, whose virus is most similar in strategy to the flu, as it lasts for a short time in the environment and evolves quickly against vaccine defenses, is unreasonable.

There was an outbreak in the United States twenty years ago and there was no epidemic

In 2003 there was an outbreak of apepox in the American Midwest, involving 71 cases spread unevenly across six states, most (39) in Wisconsin. There were zero deaths and transmission was through prairie dogs, rodents common in the region used as pets. The prairie dogs, in turn, were infected by mad joaquins, which are giant rats, imported from Africa by exotic animal traders in Texas. The name joaquim-doido is from Guinea Bissau, where Portuguese is spoken. A distributor put the two species together and 39% of prairie dogs became infected and later passed the orthopoxvirus to some of the owners. Part of the original shipment of 762 crazy joaquins was sent to Japan, where no cases of monkeypox were detected at the time. .

In addition to this outbreak in the United States, there have historically been isolated cases in Nigeria (2017-2019), United Kingdom (2019 and 2021), Singapore (2019), none resulting in large outbreaks. Suspected cases are quarantined for 17 days to prevent possible transmission and observe progression in the picture, if there is an incubated infection.

We already have a vaccine and even an antiviral

While the variant The coronavirus’ micron escapes well the defenses acquired with vaccines created for other variants, it is important to remember that human smallpox was extinguished with the use of a virus that is considered even of another species among the orthopoxviruses. One vaccine that can be used to inoculate people too young to have been immunized in the eradication campaign four decades ago is Imvanex, made by the Bavarian Nordic company. This vaccine is already specifically indicated for monkeypox. There is also the ACAM2000 vaccine, from the company Acambis, approved by the US Food and Drug Administration (FDA) in

. The CDC informs that, in addition to these vaccines and awaiting tests, there are at least three treatments being considered, such as the use of the antiviral Tecovirimat.

Brazilians may be well protected

The vaccinia virus that forms the basis for these vaccines has already caused outbreaks of a mild disease in rodents and humans in Brazil. Some researchers believe that this disease is already endemic in the country and have isolated strains from places such as Belo Horizonte, Araçatuba and Passatempo, as reported by an article by 2000 authored by Giliane Trindade, also from the CDC, and colleagues. Depending on the actual number of infected, this already forms an additional natural immunity base for older people already vaccinated if monkeypox comes here.

2019

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