Monkeypox: Diagnosis, Infection and Vaccination

WHO appoints emergency committee

Monkeypox is nowhere near as contagious as Sars-CoV-2. Nevertheless, they are now spreading to numerous countries around the world. Most people survive the disease well, but in Africa, the continent of origin, some people have died so far.

Therefore, the WHO convened the emergency committee for June 23, 2022. He should make the decision as to whether it is a “health emergency of international concern”.

This has no immediate consequences. The goal is to put the world on alert. It’s not about waiting for the situation to get out of control, said Ibrahima Socé Fall, WHO’s deputy director-general for emergency measures, according to the Tagesschau.

In January 2020, the Sars-CoV-2 outbreak was also classified as such – and yet the cases are only comparable to a very limited extent. Sars-CoV-2 was highly contagious from the start, and that too before the first symptoms appeared.

In the case of monkeypox, on the other hand, the current outbreak in many countries could still be largely contained. They are less contagious, there is an effective vaccination and medication from the start.

Socé and his colleagues should assess which measures are now advisable.

What is monkeypox?

Monkeypox is a rare viral infection. It is caused by pathogens that are closely related to the human smallpox (variola) that was once feared but is now thought to be eradicated . However, an infection with monkeypox is usually much milder. In most cases, it heals within a few weeks and is much less likely to be fatal.

Monkeypox is a so-called zoonosis, i.e. a disease that spreads from the animal kingdom to humans. It was first discovered in monkeys. In fact, however, rodents form the main reservoir of pathogens with which monkeys, humans and other mammals alike can become infected.

What symptoms does monkeypox cause?

The first symptoms of monkeypox are fever , muscle, joint and back pain as well as swollen lymph nodes and fatigue.

The characteristic skin rash appears about one to three days after these first signs of illness appear . It is initially flat, later secretion-filled blisters form. Similar to chickenpox or herpes , these crust over and eventually fall off. They can leave circular scars .

Usually, the pustules first appear on the face (in 95 percent of cases). Later they spread all over the body, including the palms of hands and soles (75 percent), the oral mucosa (70 percent) and the genital area (30 percent). The eye is also sometimes affected, namely the conjunctiva in 30 percent of cases . However, the cornea can also be affected.

The incubation period – i.e. the time between infection and the onset of the first symptoms – is usually 7 to 21 days for monkeypox.

Vaccination against monkeypox

Thanks to the close relationship of the pathogens, smallpox vaccines against the human-specific variola poxvirus also protect against monkeypox.

Vaccination is today with the smallpox vaccine Imvanex. It is approved in the USA and Canada against “human pox” and monkeypox. In the EU, the approval is officially only valid against variola, but it is also used “off-label” against monkeypox. Its protective effect against monkeypox is said to be 85 percent.

Imvanex contains live viruses. However, these have changed in such a way that, unlike the old vaccine, they cannot multiply. Those who have been vaccinated cannot therefore infect other people. It is also better tolerated than the original vaccine, which was used up until the 1980s.

For primary immunization, two doses of vaccine are required, spaced 28 days apart. According to the experts, people over the age of 50 who were routinely vaccinated against smallpox in their youth only need one dose.

After it was possible to eradicate smallpox worldwide through vaccination programs, the series of vaccinations were suspended. In Germany, smallpox vaccination was mandatory until 1976; In 1983 it was finally suspended.

People over the age of 50 have still received this smallpox vaccination and therefore often still have a certain protection against smallpox – and because of the great similarity of the viruses also against monkeypox. How high the vaccination protection actually is after decades is unclear.

Officially, only two high-security laboratories worldwide currently hold some stocks for research purposes or crisis situations. Nevertheless, the World Health Organization (WHO) and many countries have stockpiled millions of doses of smallpox vaccine. They are readily available should the disease emerge from an unknown reservoir, but also to be prepared in the event of a bioweapon attack.

However, it is the old smallpox vaccine. The modern, better tolerated vaccine is only available in limited quantities. The federal government has now ordered around 200,000 cans of it. The first 40,000 should be available soon.

Who should be vaccinated against monkeypox now?

The Standing Committee on Vaccination (STIKO) now recommends vaccination against monkeypox for people with an increased risk of infection.

This can be used both preventively and in the form of post-exposure prophylaxis after known contact with infected people or infectious material. Such a subsequent vaccination should take place as soon as possible, but it can also be useful up to 14 days after the possible infection.

People with current vaccination recommendations are:

• People who have had close physical contact with infected people
• People who have had unprotected contact with infectious material
• Laboratory workers who regularly work with infectious samples
• Men with frequently changing male partners

The fact that men who have sex with men are currently considered a risk group is based solely on the current infection situation. The virus mainly spread among them in Europe. In the case of intimate contacts, the risk of infection is the same for all partners if one person involved is infected – whether male, female or diverse. In addition, monkeypox is not a primarily sexually transmitted disease anyway! You can get infected with any close physical contact or contact with infectious material: the father with his child, the doctor with her patient, children in the toddler group among themselves.

If the disease cannot be contained, it will therefore spread more rapidly in other population groups. For this reason, so much is currently being done to push back this very unpleasant, but mostly very mild, but in rare cases fatal disease. Since the available vaccine quantities are limited, according to STIKO, people whose risk of infection is particularly high should be vaccinated first .

How dangerous is monkeypox?

Most infected people recover from the disease completely within a few weeks. Sometimes some scars remain. But it is also not uncommon for patients to die from the disease: the World Health Organization (WHO) puts the mortality rate at 3 to 6 percent. This would mean that the mortality rate would be significantly higher than, for example, with Covid-19 .

Overall, the Central African strain of monkeypox appears to be more dangerous than the West African strain currently circulating in Europe. An international overview study only published in February 2022 shows that around 10.6 percent of people who were infected with the Central African variant died. Among those affected by the West African variant, the figure was 3.6 percent.

However, such death figures from Africa are difficult to transfer to Europe. Experts assume that mortality could be significantly lower with better medical care. Patients often struggle because the pustules become infected, for example from sepsis. Better medical care should therefore have a significant impact on the mortality rate. As far as is known to date, all cases observed in Europe and North America have been mild. It is also conceivable that many cases with a mild course in African countries were not recorded, which could significantly distort the statistics.

Monkeypox is also much less contagious than Sars-CoV-2 or chickenpox. This also makes them less dangerous overall. The Robert Koch Institute (RKI) currently assesses the health risk for the general population as low.

Nevertheless, it is important to stop the further spread of the infection. Physicians are called upon to pay particular attention to possible infections. The aim is to push back the virus completely.

People with suspicious symptoms or contact with infected people should be examined at an early stage.

How do you get infected with monkeypox?

In Africa, people contract monkeypox mostly through eating or coming into contact with infected animals or their excretions. Human-to-human transmission is rare but possible. This obviously requires close contact.

As far as is known to date, monkeypox is transmitted by smear and droplet infection . Both bodily fluids such as saliva , but especially the watery secretion of the blisters and the scabby material are very infectious – similar to what is also known from herpes infections.

So you can get infected through saliva droplets in longer conversations with infected people. This is possible before the rash appears. You can later become infected through contact with the infectious blisters, but also through contaminated objects such as clothing or bed sheets. The probability of infection is naturally particularly high during sex, even if monkeypox is not an explicitly sexually transmitted disease.

How to protect yourself from monkeypox?

People who are vaccinated against smallpox also have some protection against monkeypox.

When in contact with infected people, you should avoid touching infectious skin lesions. Mouth and nose protection prevents infection via droplets that infected people release into the environment when they speak, cough and sneeze.

How is the diagnosis made?

The diagnosis of monkeypox is initially based on the typical skin rashes. However, doctors must rule out similar diseases chickenpox.

A PCR test with sample material from the affected skin areas provides reliable results. Antibody tests are unsuitable because the antibodies of all related poxviruses are very similar.

Who is particularly at risk?

All people can be equally infected with monkeypox. However, children under the age of 12 appear to be less able to cope with the disease than adults. People with a weakened immune system, for example people who are taking immunosuppressive drugs (e.g. after an organ transplant) or who have an untreated HIV infection, are also at risk of severe courses. Pregnant women also appear to be more at risk.

The infection is mainly transmitted in physical proximity, especially physical contact. Medical staff, members of the household and sexual partners of infected people are therefore particularly at risk. Anyone who has frequently changing sexual partners also carries a higher risk of becoming infected.

In Europe and North America, it is currently mainly men who have sex with men who have become infected. The disease has also been passed on within families.

How do you treat monkeypox?

Monkeypox usually heals on its own. If necessary, medication can relieve symptoms such as fever and pain. The drug tecovirimat has been approved for patients with severe courses and those with immunodeficiency since January 2022. It slows down the multiplication of viruses in the body.

According to the CDC, the vaccine Imvanex can also prevent the onset of symptoms if the patient receives it within four days of infection.

What to do if I get infected?

Anyone infected with monkeypox should avoid contact with those around them. The Robert Koch Institute (RKI) now recommends a 21-day quarantine for infected people. Even after that, the isolation should only be ended when all symptoms of the disease have healed.

In addition, there is also an “urgent recommendation” for contact persons to isolate themselves for at least 21 days. The background to the recommendation is that it can take up to three weeks for the first symptoms of the disease to appear after infection.

If you do not belong to any risk group and have a mild course, you can also isolate yourself at home. Keep in touch with your treating doctor, especially if your condition becomes more distressing. Then additional medication can ease the situation. This can also be important if the rash becomes severe or becomes infected.

Relatives who live with you in the household and remain on site during the isolation should be in good health and without any previous illnesses. Pregnant women and children under the age of 12 are also more at risk.

Be as careful as possible when dealing with healthy household members:

• Keep a distance of at least 1.5 m.
• Wear mouth and nose protection or an FFP2 mask.
• Cover skin lesions completely (e.g. with clothing or bandages).
• Avoid physical contact, such as shaking hands, hugging, or sex.
• Be careful with contaminated objects (clothing, bedding, towels) and falling scabs.

You can read more about this in the information sheet from the Robert Koch Institute on this topic “Domestic isolation in the case of confirmed monkeypox infection”.

Great Britain also carries out so-called ring vaccinations. All unvaccinated contact persons of infected people are vaccinated. This is to curb the further spread of the virus.

What is the current situation?

Since the beginning of May, monkeypox has also been detected in more and more countries outside of Africa. Most of these cases have occurred in Europe, but also in North America. Experts assume that this trend will continue.

In previous years, monkeypox had only been found in very isolated cases in people returning from travel outside of Africa. The fact that people are now infecting each other in more and more cases makes the current situation so unusual.

The steadily declining proportion of people who have been vaccinated with smallpox could play a role here. But researchers have not yet been able to rule out a genetic change that favors infection from person to person.

Experts also suspect that the virus has been circulating in the population for a while. Since the incubation period can be up to 21 days, doctors assume that more cases will be added.

Is monkeypox a new disease?

Monkeypox is not a new disease – a first case was found in 1970 in an African infant. Since then, outbreaks have repeatedly occurred on the African continent.

Outside of Africa, monkeypox has so far only been observed in people who were infected while traveling to risk areas. Chains of infection have now appeared outside of the American continent for the first time, in which people have infected each other.

Can the virus become more dangerous in the future?

Monkeypox is one of the so-called DNA viruses. Unlike the genome of RNA viruses such as the coronavirus, the DNA of monkeypox viruses is comparatively stable. Mutations that could make the pathogen more dangerous are therefore much rarer. In addition, the disease is so rare that rapid adaptation of the pathogen to humans is unlikely.

Is there a risk of a new pandemic?

So far, experts agree that this is not the case. Monkeypox is significantly less contagious than Sars-CoV-2 infections. So far there is no evidence that pathogens such as the corona virus can also spread through the air.

In addition, there seem to be hardly any cases in which the infected person does not notice any signs of illness. They are therefore likely to infect fewer people for this reason. The contacts can also be traced more reliably. Even fatal courses have hardly been observed outside of Africa.

The comparatively long incubation period for monkeypox, during which the infected are not very contagious, according to initial findings, also makes it easier to track down contact persons in good time.

Conclusion

After monkeypox cases exploded last month in countries such as Portugal, Spain and the United Kingdom — where outbreaks don’t usually occur — a rapid, global response followed, including the distribution of vaccines in some countries. But monkeypox outbreaks have been occurring in parts of Central and West Africa for years, leaving African researchers there disheartened that such resources have not been made available in their countries, where the disease’s toll has been highest. They point out that they have long been warning of the potential for the monkeypox virus, which has been behaving in new ways, to spread more widely.

The majority of laboratory confirmed cases (2933/3413; 86%) were reported from the WHO European Region. Other regions reporting cases include: the African Region (73/3413, 2%), Region of the Americas (381/3413, 11%), Eastern Mediterranean Region (15/3413, <1%) and Western Pacific Region (11/3413, <1%).  One death was reported in Nigeria in the second quarter of 2022. The United Arab Emirates has so far confirmed a total number of 13 monkeypox infections in the country and 2 recoveries from the virus. The first case of monkeypox was recorded from a 29-years-old woman who arrived from West Africa on May 24th 2022. However, it has been reported that the risk of getting infected or the risk of an outbreak is minimal as transmission requires close contact with the infected person or the person’s contaminated object, according to the Dubai Health Authority. Unlike the Covid-19 pandemic, monkeypox is a known pathogen. There are more tools including vaccines available to prevent and treat monkeypox than existed when the coronavirus first emerged. Still, even a large monkeypox outbreak would likely be much easier to control than Covid-19. The virus is not considered contagious until people show symptoms, which means it could be more difficult for people to accidentally spread it. Ultimately, experts say because of the Covid-19 pandemic, public health officials around the world are already in a strong place to control any sort of disease outbreak.