Recently, the World Health Organization has categorized mpox, previously referred to as monkeypox, as a public health emergency due to the emergence of a potentially lethal strain in Africa.
Mpox surged into the spotlight during the global outbreak of 2022, impacting the U.S., Europe, and Australia among others. The virus exists in two primary variants, known as clade I and clade II, and spreads primarily through close contact.
The earlier outbreaks in the West were mostly attributed to clade II and largely spread through sexual contact, particularly among men who have sex with men. Now, however, Africa is facing a rise driven by a new variant of clade I, known as clade Ib, believed to be more virulent than earlier strains.
So far in 2023, the Democratic Republic of Congo (DRC) has reported over 22,000 mpox cases and more than 1,200 fatalities, likely linked to the clade Ib variant. This variant has also reached neighboring countries such as Burundi, Kenya, Rwanda, and now Sweden.
Jonas Albarnaz, a research fellow at the UK’s Pirbright Institute, indicated the case in Sweden should prompt health authorities to enhance surveillance and contact tracing efforts to catch new cases quickly.
Are Current Mpox Vaccines Effective Against New Strains?
To determine the effectiveness of existing mpox vaccines, it’s important to recognize that mpox is similar to smallpox, both belonging to the orthopoxvirus family. Albarnaz highlighted that proteins shared by orthopoxviruses mean that immunity from one can offer protection against another, validating the use of smallpox vaccines for mpox.
Thus, current vaccines should effectively combat both clade II and clade I viruses, including the clade Ib variant. The primary vaccine available in the U.S. is JYNNEOS, administered in two doses with a four-week interval.
Who Should Get Vaccinated for Mpox?
According to the U.S. Centers for Disease Control and Prevention (CDC), individuals at risk include:
- Gay, bisexual, transgender, or nonbinary folks who’ve had:
- A recent STD diagnosis
- Multiple sexual partners
- Sex in commercial venues
- Sex during large public events in areas with ongoing mpox transmission
- Partners of those described above.
- Anyone expecting to be in such situations.
Vaccination can also apply to those under 18 who have had close contact with someone infected.
The CDC reports over a million doses of JYNNEOS have been given in the U.S., leading to questions about the necessity of booster shots. Currently, booster doses are not advised, except for those in high-risk occupational settings.
Should Americans Be Alarmed About Mpox?
The U.S. Health and Human Services Department maintains that the general public’s risk remains low. Wastewater analysis has shown minimal virus presence, with just a few sites testing positive for clade II.
Even if clade I arrives in the U.S., experts believe it may result in lower severity than observed in the DRC.
Nonetheless, awareness of the ongoing outbreak is crucial. Gavigan noted that while the current U.S. risk is low, past experiences have shown how outbreaks can escalate quickly across borders. Vigilance and awareness are key.
A significant challenge remains the limited availability of vaccines in outbreak regions, as this constrains control efforts. Albarnaz advocates for a united global response to combat mpox spread in Africa to avert a repeat of the 2022 outbreak.
In addition to vaccination, the CDC advises these precautions to stay safe from mpox:
- Avoid close contact with individuals displaying mpox symptoms, like skin lesions.
- Steer clear of wild animals in endemic areas.
- Don’t touch contaminated items, such as clothing or bedding from infected individuals.