Monkeypox now also in the Netherlands. What is known about this virus?

‘A few cases’ of infection with the monkeypox virus have been identified in the Netherlands, the RIVM reported on Saturday afternoon. Belgium, France, Germany and Israel also reported their first infections in the past week, after the virus appeared in the United Kingdom on May 6, and then elsewhere in Europe, North America and Australia.

Which virus is it exactly? And should we be concerned? Eight questions and answers about the monkeypox virus.

1.What is monkeypox virus?

The monkeypox virus is a DNA virus of the genus Orthopox virus† It is closely related to the ‘common’ smallpox virus, which was eradicated worldwide thanks to vaccination around 1975; only in laboratories does it survive. That virus was highly contagious and had a death rate of up to 30 percent.

Monkeypox virus is common among rodents in Africa, but it is not known whether they are the primary host of the virus in nature. A Danish doctor discovered the virus in monkeys in 1958 at a research center, hence the name monkey pox. But otherwise, monkeys — and humans — seem to be just incidental victims.

2.Do people often get infected?

Since 1970, people have occasionally been infected with the monkeypox virus, almost exclusively in Central and West Africa. They get the virus through contact with infected animals or people. So far, the virus has been diagnosed in humans in eleven African countries. In 2017, an outbreak of in Nigeria about 200 people sick; furthermore, the number of infections in Africa is relatively low.

In 2003 there was a first case outside Africa. That was in the US, with a traveler who had been to Nigeria. In recent years, sporadic infections have been reported in the United Kingdom, Singapore, Israel and the US, always with a link to Nigeria. Those outbreaks quickly died down.

3.And now?

In May 2022, that pattern appears to be changing. A case surfaced in London on May 6, followed a week later by six more infections in that city. Reports soon followed from Portugal, Spain, Italy, Canada, the US and Australia, among others. Remarkably enough, in most cases there is no direct link with Africa – and often no known mutual link either.

The World Health Organization records cases worldwide, but does not update the numbers on its website every day. The Global.Health collective (an open data initiative by scientists from Oxford and Harvard, among others) does that† on this site the counter stood at 145 cases worldwide on Saturday, about half of which were confirmed with certainty.

4. Is the monkeypox virus dangerous?

The virus is less contagious and less deadly than the ‘regular’ smallpox virus; vaccording to the World Health Organization mortality in Africa is on average around 3 to 6 percent. Mortality in Nigeria is around 10 percent in the Central African or Congo variant and around 3 percent in the milder West African variant. The cases examined in May would concern the latter variant. According to the RIVM contamination is “usually mild”.

About 5 to 21 days after infection (usually about 6 to 13), people can develop symptoms: fever, fatigue, spots on the skin and characteristic ulcers and blisters all over the body. These symptoms last for about two weeks. Then the blisters dry up and disappear. People can infect each other through skin contact, body fluids or touching, for example, contaminated sheets. As far as is known, the virus is not transmissible through the air.

5. Who gets infected now?

Monkeypox usually mainly affects children, the elderly and people in vulnerable health. However, now mainly young men are infected. Details are not known for all cases, but the data from Global.Health is abundantly clear: of the 145 confirmed and suspected cases of disease, the gender is known, and only one is female.

It European Center for Disease Prevention and Control (ECDC) reports that in many cases it concerns gay men. This would also explain why the blisters mainly occur on the buttocks and around the genitals during the recent outbreaks. But the ECDC emphasizes that everyone should be aware of it, even outside the gay scene. STD AIDS Netherlands warns that monkey pox is not a sexually transmitted disease (STD) in the traditional sense, “because the virus is (also) transmitted during sex and not just through sex. Just like you can get the flu during sex, but not because of sex.”

6.Is there anything you can do about it?

The US Centers for Disease Control and Prevention (CDC) report , based on previous research in Africa that the common smallpox vaccine provides 85 percent protection against monkeypox infection. Also, administration of this vaccine within four days after infection would help against severe symptoms. It is not yet known whether this is also the case in the current situation. Some countries are now vaccinating healthcare workers who treat monkey pox patients.

Earlier in 2022, the European Medicines Agency EMA an antiviral medicine against smallpox (tecovirimat) for use in patients with monkeypox.

7.What do virologists say?

Marion Koopmans, professor of virology at Erasmus MC in Rotterdam, mentioned the outbreak on Twitter “very exceptional” and “worrying” because the virus is now appearing in so many different countries simultaneously, often with no direct link to Africa. “The virus as we know it is not very contagious. So the question is: is there anything special going on? For example, a first infected person with many direct contacts? Or has the virus changed? Could it have become more contagious?” It is not yet well known which genes determine this contagiousness, according to Koopmans. “We urgently need more information.”

Portuguese researchers published Last Thursday, the complete genome of the virus as it appeared in Portugal at the beginning of May was the first. They reported no exceptional mutations. The sequenced virus most closely resembled the variant found in travelers from Nigeria in the United Kingdom, Singapore and Israel in 2018 and 2019. What that could mean, the Portuguese leave open.

8. What does the RIVM say?

“It is really too early to explain the current outbreaks,” said a RIVM spokesperson on Friday. “The virus is still being extensively researched.” This also includes source and contact research, because the recent distribution pattern is still a mystery.

According to the spokesperson, there is no reason to panic yet. “We have to be vigilant. That is why we are now arguing with the minister for a notification obligation.” In any case, the Netherlands has “sufficient stock” of the regular smallpox vaccine, he says when asked.