Monkeypox cases have been reported in many European and American countries. What’s so rare and unusual about it?

Since May this year, the United Kingdom, Portugal, Spain, the United States and other countries have reported confirmed or suspected cases of monkeypox, which has aroused concern. According to foreign media reports, the outbreak of monkeypox in many countries is "rare and unusual".

Uncovering the “True Face” of Monkeypox

Monkeypox is a zoonosis caused by infection with the monkeypox virus. Common symptoms include fever, rash, severe headache, swollen lymph nodes, back pain, muscle aches, fatigue, etc. Swollen lymph nodes are a unique feature of monkeypox compared to smallpox.

Monkeypox is usually a self-limited disease with symptoms lasting 2 to 4 weeks. Most people who are infected recover within a few weeks, but some people die from severe illness. Severe cases are more common in children and are related to the degree of virus exposure, the patient's health status and the nature of complications. Underlying immune deficiencies may lead to worse outcomes.

Complications of monkeypox include secondary infection, bronchopneumonia, sepsis, encephalitis, and corneal infection leading to vision loss. Monkeypox case fatality rates have historically ranged from 0% to 11% in the general population and are higher in young children. More recently, monkeypox case fatality rates have been around 3%-6%.

Monkeypox virus is a close relative of smallpox virus, belonging to the genus Orthopoxvirus of the Poxviridae family. The genome structures of the two are very similar, and there are many similarities in biological characteristics and pathogenicity. It can be understood that the two are of the same origin. Although it is called monkeypox virus, it does not only exist in monkeys. It is mainly transmitted to humans through various wild animals such as rodents and primates, and can also be transmitted secondary between humans.

What's "unusual"?

1. The scope of transmission and the number of cases are beyond the past

Human monkeypox was first identified in 1970 in a 9-year-old boy in the Democratic Republic of the Congo, and has since spread mainly to rainforest countries in west and central Africa, occasionally to other areas.

In 2003, the first monkeypox outbreak outside of Africa occurred in the United States. Before May this year, cases of monkeypox imported from Africa had occurred in Israel, the United Kingdom, Singapore and other countries, but the scope of spread and the number of cases were very limited. This time, the monkeypox epidemic has spread from Africa to Europe and the United States, and the number of cases has also increased a lot.

UK: 9 confirmed cases, 1 suspected case

On May 7, the UK Health and Safety Agency reported the first recent case of monkeypox (the patient had a history of travel to Nigeria, developed a rash on April 29, and arrived in the UK on May 4), which was the starting point of this round of monkeypox outbreak. Since then, as of May 18, the UK has reported a total of 9 confirmed cases and 1 suspected case.

United States: 1 confirmed case, 7 suspected cases

On May 18, the U.S. Centers for Disease Control and Prevention confirmed a confirmed case of monkeypox in Massachusetts, the first confirmed case of monkeypox in the United States in 2022. It is reported that the adult man infected with monkeypox had recently traveled to Canada.

Canada: 2 confirmed cases, 17 suspected cases

The Public Health Agency of Canada confirmed on the evening of May 19 that two cases of monkeypox have been confirmed in Canada, marking the first cases of monkeypox infection in Canada. Montreal health officials revealed that they are investigating 17 suspected cases in the area.

Spain: 7 confirmed cases, 22 suspected cases

Spain's El País reported on the 20th, citing health officials in the Madrid region and data from two local hospitals, that the monkeypox virus began to spread in Madrid in late April 2022, and most known cases of infection were not confirmed until early May. As of May 19 local time, seven cases of monkeypox have been confirmed in the Madrid region, and another 22 suspected cases of monkeypox infection are awaiting research and confirmation.

Portugal: 5 confirmed cases, 15 suspected cases

As of May 18, local time, Portugal has reported 5 confirmed cases of monkeypox and 15 suspected cases. Neither Portugal nor Spain has reported similar cases before.

Italy: 1 confirmed case

On May 19th local time, the National Institute of Infectious Diseases Hospital in Rome, Italy reported the country's first case of monkeypox.

Sweden: 1 confirmed case

According to Swedish TV reports on May 19th local time, the Swedish Health Bureau confirmed that a confirmed case of monkeypox was found in the capital Stockholm.

2. The mode of transmission is different from the past: previously it was imported transmission, but this time it was local community transmission and the cause is still unknown

Unlike previous imported cases, this round of monkeypox epidemic in Europe and the United States is almost certain to be community infection.

Most of the monkeypox cases found in many European and American countries have not been to Africa, and the source of their infection is still unknown. Susan Hopkins, chief medical adviser at the UK Health and Safety Agency, said: "The latest cases in the UK, as well as cases in other European countries, confirm the suspicion that monkeypox may have begun to spread in the community."

In addition, in addition to the fact that no known links have been found between cases in various countries, there is no connection between cases in Europe and the United States, which means that multiple chains of transmission may exist.

Since there is no history of travel to Africa, how did the local infection occur? The UK Health and Safety Agency reported on May 17 that the country's latest cases "mainly occurred in homosexual, bisexual or men who have sex with men."

At present, the cause of the monkeypox outbreak in Europe and the United States has not yet been determined. Is it a new way of transmission of monkeypox? Is it a new mutation of the monkeypox virus? Or is it that since the outbreak of the new crown epidemic, various wild-caught or smuggled monkeys used for experiments have flowed into the European and American markets, leading to an outbreak of infectious diseases? It is still uncertain.

Scientists are studying and treating new cases of monkeypox seriously. As ordinary individuals, we must take daily precautions, but there is no need to panic. For the public, to prevent monkeypox infection, we must avoid unprotected contact with wild animals, especially those that are sick or dead (including their meat, blood and other parts). In addition, all foods containing animal meat or animal parts must be thoroughly cooked before consumption.

References:

https://www.who.int/news-room/fact-sheets/detail/monkeypox

https://www.who.int/emergencies/disease-outbreak-news/item/2022-DON383