In this latest video from MedCram, Dr. Seheult discusses Mpox, formerly known as Monkeypox and what the latest updates are from the summer of 2024. It was declared a public health emergency of international concern on 8/14/24.
What is Mpox?
Back in 2022, the outbreak of Mpox was first discussed. We know there are two families of Mpox known as clades. There is Clade I which is endemic in Africa and typically was found in the Congo, was more infectious, caused more disease and was more deadly up to 10% mortality. Clade II was in West Africa, less infectious and caused less disease and was overall less deadly. It was Clade IIb that caused the outbreak back in 2022. The survival rate of that outbreak was 99.9%. It was seen primarily in the groups of men having sex with men and in cases where there was significant close contact.
What clade is of concern at this time?
At this current outbreak, it is Clade Ib that is causing concern. This clade being more infectious, people have developed the disease after contact not only of a sexual nature but also from clothing and bedding. At this time, we are not seeing a 10% mortality but instead it appears to be currently closer to 1%. When this was declared an emergency by the WHO, it allowed public funding to be released and enhances public awareness of this to prevent this from spreading further.
How many people has Mpox affected?
In Africa about 17000 persons have been infected with 96% of that number being from the Democratic Republic of Congo. There have been 500 deaths, 70% of them have been in children. One of the determining factors in the deaths was whether the person had been exposed to smallpox in the past. Smallpox is very closely related to Mpox. In recent times, smallpox vaccination has been phasing out and unfortunately, it’s the children born recently that have not had exposure to it that have been at higher risk of death when exposed to Mpox.
Where did Mpox come from?
Mpox was first seen in monkeys. However, it is common in mice, groundhogs and small animals. Transmission from small animals comes from bites and scratches, ingestion of the animal and having contact with the skin and fur of an infected animal. When humans come down with the rash, if usually follows an incubation of 3-17 days, followed by fever of 1-3 days. It can be spread among humans from rash, scabs, bodily fluids, respiratory droplets, sheets and fomites. Typically the contact needs to be a prolonged contact of about 4 hours.
What are possible treatments?
Options of vaccination include the vaccines named ACAM 2000 and Jynneos. These were both initially created for smallpox but since the two diseases are so close to each, the smallpox vaccine has been able to be used for Mpox outbreaks. ACAM 2000 is a live virus that replicates and the injection needs to be done in multiple places and needs to see a “take” on the skin that will then lead to immunity. It has more side effects than the alternative vaccine. The Jynneos is a live virus that is attenuated and it does not replicate. You don’t need to worry about a “take”. This vaccine is now able to be given intradermally and requires only one fifth of the dose needed normally. You need a total of 2 shots given 28 days apart. The best study which is a case control study and not ideal, showed an efficacy of only 66% after two doses of the vaccine. The CDC lists on their website that two doses are more effective than one dose. Even when infections have occurred after two vaccine doses, they have typically been milder than the infections among people who are not vaccinated. The vaccine is recommended for high risk persons as noted on the CDC website. The CDC does not recommend routine immunization against Mpox for the general public unless sexual risk factors are present.
MedCram has a CME course on Mpox for further information.
LINKS / REFERENCES:
Monkeypox: What is it and how can it be prevented? (Mayo Clinic) | https://www.mayoclinic.org/diseases-c…
Monkeypox virus evades antiviral CD4+ and CD8+ T cell responses by suppressing cognate T cell activation (PNAS) | https://www.pnas.org/doi/10.1073/pnas…
WHO declares mpox a global public health emergency for second time in two years (NBC) | https://www.nbcnews.com/health/health…
Public health emergencies of international concern: a historic overview (Journal of travel medicine) | https://www.ncbi.nlm.nih.gov/pmc/arti…
Recommendations for Use of JYNNEOS Vaccine (CDC) | https://www.cdc.gov/poxvirus/mpox/int…
Infection- plus vaccine-induced immunity led to decline of mpox in Netherlands, data reveal (UofMN) | https://www.cidrap.umn.edu/mpox/infec….
Vaccine Effectiveness of JYNNEOS against Mpox Disease in the United States (NEJM) | https://www.nejm.org/doi/full/10.1056…
Risk of Clade 1 Mpox Outbreaks Among Gay, Bisexual, and Other Men Who Have Sex With Men in the United States (CDC) | https://www.cdc.gov/forecast-outbreak…
Sustained Human Outbreak of a New MPXV Clade I Lineage in Eastern Democratic Republic of the Congo (Nature Medicine) | https://www.medrxiv.org/content/10.11…
Mapping the distribution and describing the first cases from an ongoing outbreak of a New Strain of mpox in South Kivu, Eastern Democratic Republic of Congo between September 2023 to April 2024 (medRxiv) | https://www.medrxiv.org/content/10.11…
Clade I–Associated Mpox Cases Associated with Sexual Contact, the Democratic Republic of the Congo (CDC) | https://wwwnc.cdc.gov/eid/article/30/…