Mpox, a viral disease caused by the monkeypox virus (Orthopoxvirus genus), typically presents with flu-like symptoms followed by a characteristic rash. A common question is whether a person can contract mpox more than once.
Reinfection and Immunity to Monkeypox
Confirmed reinfection with mpox is uncommon, though not impossible. After an initial mpox infection, the human body generally develops an immune response, producing antibodies and specialized T-cells that help fight off the virus. This natural immunity offers protection against subsequent exposures, similar to what is observed with other orthopoxviruses like smallpox.
Studies on smallpox, a related virus, indicate that immune cells can persist in the blood for many decades, and neutralizing antibodies can be found for decades. While direct long-term data for mpox is still being gathered, the immune memory for poxviruses is generally long-lasting. However, reports of reinfection, while rare, have emerged, suggesting that natural immunity may not be entirely absolute or permanent for everyone.
Factors That May Influence Reinfection
While generally rare, certain conditions can influence the likelihood of mpox reinfection. Individuals with significantly weakened immune systems, such as those with underlying health conditions or those taking immunosuppressive medications, may have a reduced ability to mount a robust, long-lasting immune response after an initial infection, making them more susceptible.
Re-exposure to a very high dose of the virus or prolonged, intense contact with an infected individual can also overwhelm even a healthy immune system, leading to reinfection. Additionally, the theoretical emergence of a new, distinct viral strain of mpox could present a challenge to existing immunity, as antibodies developed against one strain might offer less protection against a significantly altered variant. The cessation of routine smallpox vaccination has also led to a decline in cross-protective immunity against orthopoxviruses, potentially contributing to mpox re-emergence.
Preventing Future Exposure
To minimize the risk of future mpox exposure, individuals should follow public health recommendations. Avoiding close, skin-to-skin contact with anyone displaying a rash or other symptoms consistent with mpox is recommended. This includes refraining from intimate contact like kissing, hugging, or sexual activity if a partner has symptoms or lesions.
Practicing good hand hygiene, such as frequent washing with soap and water or using an alcohol-based hand sanitizer, is a preventive measure, especially after any potential contact with an infected person or contaminated objects. Avoiding contact with objects that a person with mpox has used, such as bedding, towels, or clothing, can help prevent indirect transmission. For at-risk groups, vaccination with the JYNNEOS vaccine is recommended, offering additional protection against the virus.