Medical Biotechnology | Monkeypox is coming in full force, how do we respond?

As of May 25, 2022, according to statistics from the European Centre for Disease Prevention and Control and the World Health Organization (WHO), at least 226 cases of monkeypox have been reported in at least 21 countries.

The current round of monkeypox outbreak was first reported in the UK on May 7, followed by reports in Spain, Portugal, Australia, Belgium, Canada, France, Germany, Italy, the Netherlands, Sweden and the US. More than two-thirds of the cases were in Europe, with 78 reported in the UK, 51 in Spain and 37 in Portugal. In North America, nine cases were reported in the US and 15 in Canada.

Previously, monkeypox was only prevalent in Africa, and cases outside Africa were generally related to people who had traveled to Africa, or had contact with African travelers, or were related to infected animals imported into the country. This year's outbreak unexpectedly occurred in European and American countries where monkeypox is not prevalent, and most of the patients had no history of travel to African countries. This is why this monkeypox outbreak has attracted great attention from public health experts. For this reason, on May 20, WHO held a technical advisory group meeting to discuss information and response strategies related to monkeypox, and issued a warning that the outbreak would spread further.

So what causes monkeypox? What are its symptoms? And what can we do about it?

Orthopoxvirus, same family as smallpox

Monkeypox is a viral zoonosis caused by the monkeypox virus, which can be transmitted between animals and humans, and secondary transmission between humans. Its animal reservoirs include a range of rodents such as squirrels, Gambian wallabies, dormice, and non-human primates.

Monkeypox virus belongs to the genus Orthopoxvirus of the Poxviridae family (smallpox virus also belongs to Orthopoxvirus), and is an enveloped double-stranded DNA virus. Monkeypox virus is resistant to ether and has strong resistance to drying, but is easily inactivated by chloroform, methanol and formalin. It is also easily inactivated by heating at 56°C for 30 minutes.

There are two distinct genetic clades of monkeypox virus, the Central African clade and the West African clade. The West African clade has a case fatality rate of about 3.6%, while the Central African clade has historically caused more severe disease, with a case fatality rate of about 10.6%, and is considered more contagious.

Since the eradication of smallpox in 1980 and the subsequent cessation of smallpox vaccination in humans, monkeypox has become the most important orthopoxvirus in public health.

Close contact can easily spread

Monkeypox is similar to smallpox, with an incubation period of about 5 to 21 days, with an average of about 12 days. The initial symptoms after onset include high fever, headache, chills, rapid heartbeat and body aches. The most typical symptom is a large rash on the skin 2 to 3 days later.

Unlike human pox, monkeypox causes swollen lymph nodes. People infected with the monkeypox virus are prone to complications such as sepsis, osteomyelitis, encephalitis, meningitis, and pneumonia. Death usually occurs within 1 or 2 weeks of onset, and the mortality rate is relatively high in young children.

The first confirmed case of monkeypox in human history occurred in the Democratic Republic of the Congo in 1970. Humans are infected mainly through bites from infected animals or direct contact with blood, body fluids, or monkeypox lesions from infected animals. Occasionally, monkeypox is transmitted from person to person, and is generally believed to be transmitted through large amounts of respiratory droplets containing the virus during direct, prolonged face-to-face contact. In addition, monkeypox can also be transmitted through direct contact with infected people's body fluids or virus-contaminated contaminants (such as clothing and bedding).

The WHO warns that monkeypox is more likely to spread among people who have close physical contact with symptomatic cases. In addition, it can be transmitted from mother to child and sexually.

Prevention is the priority in responding to the epidemic

At present, countries have taken some measures to deal with the current epidemic. For example, the Belgian health department issued a statement on May 19, requiring monkeypox cases to self-isolate for 21 days. After the first confirmed case of monkeypox in the United States, it immediately spent nearly $300 million to purchase 13 million doses of vaccines that can prevent monkeypox and smallpox. The U.S. Food and Drug Administration (FDA) has approved the intravenous formulation of TPOXX, a smallpox treatment drug. As early as 2019, the U.S. FDA had approved the first monkeypox vaccine.

Adequate vaccine preparation

Monkeypox virus, smallpox virus, and cowpox virus all belong to the genus Orthopoxvirus in the family Poxviridae.

Humans once used cowpox to eradicate the terrible smallpox. Edward Jenner, the father of modern vaccines, concluded that vaccination with a small amount of cowpox virus can obtain immunity to smallpox while ensuring a mild reaction. This is based on the cross-immunity mechanism between closely related viruses. Countries around the world have completely eradicated the smallpox virus through smallpox vaccination. On December 9, 1979, scientists announced that smallpox had been eradicated. On May 8, 1980, the WHO announced that smallpox had been completely eradicated, and countries around the world gradually stopped smallpox vaccination. China stopped smallpox vaccination in 1981, and by 1984, there was no smallpox vaccination in the country.

The similarities between human poxvirus and monkeypoxvirus can also form cross-immunity. In practice, the effectiveness of smallpox vaccine in preventing monkeypox virus can reach 75% to 85%. Therefore, with the changes in the monkeypox epidemic, many countries have begun to prepare for the re-vaccination of smallpox/monkeypox vaccine, and some special populations have already completed the vaccination.

my country also has sufficient vaccine preparations to deal with the monkeypox outbreak. However, whether to carry out smallpox vaccination is a government decision. The WHO pointed out that although this outbreak is unusual, it is still "controllable", so large-scale monkeypox vaccination is not needed for the time being.

The current epidemic prevention policy is effective

At present, no cases of monkeypox have been found in my country, and the main prevention and control goal is still to prevent importation. In my country's ongoing COVID-19 prevention and control work, the current "14+7 days" quarantine policy for incoming personnel is also effective in preventing the introduction of monkeypox. If an incoming person is infected with the monkeypox virus by chance, considering that the incubation period of monkeypox is usually 6 to 13 days, and the longest record is 21 days, as long as the entry quarantine policy is perfect, it can also block the potential threat.

Pay attention to personal protection

Individuals should avoid contact with animals that may carry the monkeypox virus, avoid eating game, and avoid contact with any items that have come into contact with monkeypox patients, such as bedding; after contact with suspected infected animals or humans, hands and related parts should be cleaned as soon as possible.

Although the monkeypox outbreak is fierce, as long as we respond correctly, we can prevent it from spreading in the country. The WHO said that the monkeypox virus is not a very easy virus to spread and has not caused severe illness so far. The global epidemic is currently under control. Maintaining good hygiene habits and ensuring safe sexual behavior will help control the spread of the monkeypox virus.

Author: Yaohuluwa Medical and Biological Science Popularization Group