Mpox is in the news. The World Health Organization declared a global health emergency due to the alarming spread of mpox in Central Africa. The declaration focuses much needed attention to respond to the outbreak in Central Africa. To understand what this means locally, we sat down with Dr. Matthew Golden, Public Health’s Director of the HIV/STI/HCV Program for some context.
We’ve heard about mpox outbreaks in Central Africa. Is it the same kind of mpox that we see here?
There are two main types of mpox, clade I and clade II. Within these clades, there are subtypes. The large outbreak that is now ongoing in several countries in Central Africa, including the Democratic Republic of Congo (DRC), is caused by clade I. This type tends to be more severe and is not the type that caused the outbreak here in 2022.
Both mpox clades primarily spread through close, often skin-to-skin contact with a person with mpox, though some cases result from contact with infected animals or possibly through contact with objects such as bedding and clothing. At least some of the current outbreak in the DRC is caused by a newly identified type of mpox called clade Ib. This subtype has occurred in cisgender female sex workers, suggesting that it can be sexually transmitted.
No cases of clade I mpox have been reported locally or in the United States at this time. However, one case has been identified in Sweden and one in Thailand. Both people had traveled to an affected nation in Africa.
We don’t know how likely it is that clade I mpox will come to the United States. Mpox needs close or intimate contact to spread, so casual contact during travel, like being in the same room, is not likely to cause the disease to spread. We do not currently recommend vaccination for members of the general public who are not at high risk of exposure to mpox.
What is the local mpox situation currently?
Locally, we still have some cases of clade II mpox, although at a much lower rate than back in 2022. These cases are most often sexually transmitted and have occurred primarily in gay, bisexual, and other men who have sex with men. The number of cases plummeted in late 2022 as a result of behavior change and widespread vaccination among gay, bisexual, and other men who have sex with men.
Who should get vaccinated?
Public Health recommends the following people receive two doses of mpox vaccine:
- Individuals who have had skin to skin or other close contact with someone with mpox.
- Gay, bisexual, and other men who have sex with men. And transgender/non-binary people who have sex with men, or with other transgender/non-binary people.
- Individuals who have engaged in commercial and/or transactional sex (for example, sex in exchange for money, shelter, food, or other goods or needs) in the past six months.
People who have already received two doses of vaccine or who have had mpox infection are considered immune to mpox. At present, Public Health and the CDC do not recommend that people receive booster doses of mpox vaccine.
People who do not meet the above criteria do not need to get the mpox vaccine at this time.
Does the vaccine protect against all the current types of mpox?
Two doses of mpox vaccine are thought to be approximately 80% effective in preventing clade II mpox, with a higher level of efficacy in preventing severe disease. We believe that the vaccine will also protect against clade I mpox, though data on how much the vaccine prevents clade I are very limited.
Mpox information and resources:
CDC – Mpox outbreak in Democratic Republic of the Congo (DRC)
CDC – Social Gatherings, Safer Sex and Mpox
Originally published 8/30/2024