There have been more than 4,100 confirmed cases worldwide, including at least 13 in Australia.
Sydney:
The World Health Organization (WHO) has decided not to declare monkeypox a public health emergency of international interest. That may change in the future.
However, WHO Director-General Tedros Adhanom Ghebreyesus said he was “deeply concerned” by the evolution of the monkeypox threat, which he said had reached more than 50 countries.
There have been more than 4,100 confirmed cases worldwide, including at least 13 in Australia.
The WHO also acknowledged that there were many unknowns about the outbreak.
Here are three things we know about monkeypox and three things we want to find out.
3 things we know
1. Monkeypox is caused by a virus
Monkeypox is a large DNA virus that belongs to the family of orthopoxviruses. Unlike the related smallpox virus, smallpox, which only affected humans, the monkeypox virus is found in rodents and other animals in parts of Africa.
We know of two clades (clusters of viruses), and it is the less serious of the two currently circulating outside Africa.
Orthopoxviruses are stable viruses that do not mutate much. However, multiple mutations in the virus causing the current outbreak have been described.
In the United States, at least two separate strains have circulated, suggesting multiple introductions to the country.
2. You may be infected for more than a week and not know it
It takes an average of 8.5 days from infection to show symptoms, such as enlarged lymph nodes, fever, and a rash, which usually look like fluid-filled blisters coming out. People are infectious while having the rash, and are usually infectious for about two weeks.
Children are the most affected and have a higher risk of dying from the disease. Historically, in the endemic countries of Africa, almost all deaths have been in children.
The European epidemic is mostly in adult men, so this, along with better access to care, may explain the low death rate in these countries.
3. We have vaccines and treatments
Vaccines work. Previous smallpox vaccination provides 85% protection against smallpox. Smallpox was declared eradicated in 1980, so most mass vaccination programs ceased in the 1970s.
Australia never had a massive smallpox vaccine. However, it is estimated that 10% of Australians have been vaccinated in the past, mostly migrants.
Vaccines protect for many years, but immunity decreases. Therefore, declining population-level protection is likely responsible for the resurgence of monkeypox seen since 2017 in Nigeria, one of the seven endemic hot spots in Africa.
Mass vaccination is not recommended. But vaccines can be given to contacts of confirmed cases (known as post-exposure prophylaxis) and people at high risk of contracting the virus, such as some laboratory or health workers (pre-exposure prophylaxis).
There are also treatments, such as immunoglobulin vaccinia and antivirals. These developed against smallpox.
3 things we want to find out
1. How important are these new mutations?
The virus causing the current outbreak has several mutations compared to the versions of the virus circulating in Africa. However, we do not know whether these mutations affect the clinical disease and how the virus spreads.
The monkeypox virus has a very large genome, so it is more complex to study than smaller RNA viruses, such as the flu and SARS-CoV-2 (the virus that causes COVID) .
Experts wonder if the mutations have made it more contagious or changed the clinical pattern to look more like a sexually transmitted infection. A Portuguese study shows that mutations probably make the virus more transmissible.
2. How does it spread? Is this changing?
Monkeypox has not been described in the past as a sexually transmitted infection. However, the current transmission pattern is unusual. There appears to be a very short incubation period (24 hours) after sexual intercourse in some cases, but not in all.
It is a respiratory virus, so the transmission of aerosols is possible. But historically most of the transmission has been from animal to human. When there was transmission between humans, this usually involved close contacts.
The rapid growth of the epidemic in non-endemic countries in 2022, however, has been due to the spread among humans. There may be many more cases than have been officially reported.
We don’t know why the pattern has changed, whether it is sexually transmitted or simply intimate contact on specific, globally connected social networks, or whether the virus has become more contagious.
The virus is found in the rash, mouth and semen, but this does not show that it is sexually transmitted.
3. How far will it extend? Does COVID make a difference?
Will this spread more in the community? Does the COVID pandemic increase the risk? Possibly, yes.
Nor should we drop the ball on surveillance in the community at large or stigmatize the LGBTQI community.
Due to the decline in smallpox vaccine immunity worldwide and the spread of monkeypox already in many countries, we can see that the epidemic is spreading more widely.
If it does and it starts infecting a large number of children, we could see more deaths because the children have a more serious infection.
Therefore, we should monitor globally to detect groups of fever and rashes, and misdiagnosis such as chickenpox, foot-and-mouth disease, herpes simplex, or other eruptive diseases.
Another factor is COVID. As people recover from VOCID, their immune system deteriorates. Therefore, people who have had COVID may be more susceptible to other infections.
We see the same with measles infection. This weakens the immune system and increases the risk of other infections for two to three years later.
If the epidemic sets in in countries outside the endemic areas, it can infect animals and create new endemic areas in the world.
It is important that we do everything we can to stop this epidemic.
C Raina MacIntyre, Professor of Global Biosafety, Principal Investigator of the NHMRC, Head of the Biosafety Program, Kirby Institute, UNSW Sydney
This article is republished from The Conversation under a Creative Commons license. Read the original article.