In today’s interconnected world, outbreaks of infectious diseases grab headlines and create widespread panic. But sometimes, a disease outbreak quietly fades away without much fanfare. This was the case with a recent outbreak of mousepox (mpox) in Australia. While it initially caused concern among scientists and policymakers, the virus seemed to disappear almost as quickly as it had appeared. Some experts believe that a newly discovered phenomenon called “network immunity” may have played a key role in containing the outbreak. In this article, we explore what exactly network immunity is, and how it could be leveraged to fight future disease outbreaks.
New research presented at the European Congress of Clinical Microbiology & Infectious Diseases suggests that a combination of infection-induced immunity and behavioral changes among populations at risk for mpox, primarily gay, bisexual, and other men who have sex with men (MSM), contributed to the end of the global mpox outbreak in 2022. Although vaccination programs were launched around the world as cases peaked, the decline in mpox cases had already started before a substantial proportion of the population at risk had been vaccinated. The research found that the median number of sexual partners in the previous three weeks declined by 0.86 partners per week as the outbreak continued. The researchers also split participants into two groups: a core-group defined as those with a history of syphilis and a noncore group without a history of syphilis. The core-group PrEP users reported 1.31 more partners per week at the outbreak’s height than non-core-group members. Over time, the number of partners in both groups increased by 1.008 partners per week. The research suggests that core members of the sexual network were infected first, with noncore and peripheral members being infected later. The implication is that infection-induced immunity in the core population generated a “network immunity” among the core, noncore, and other populations that halted the outbreak. The researchers are now working on serological and modeling studies to determine whether this hypothesis is true.
In conclusion, the concept of network immunity has emerged as a promising approach to control the spread of infectious diseases. By understanding how a disease spreads, healthcare professionals and policymakers can harness the power of communities to address outbreaks swiftly and effectively. In the case of the mpox outbreak, the collaboration between the community and the authorities played a crucial role in diminishing the disease’s impact. However, we cannot overlook the importance of vaccinations and preventive measures to curtail the spread of contagious diseases. As we continue to battle the COVID-19 pandemic, the idea of network immunity offers new avenues for control and management, but it should be complemented by a multi-faceted strategy that adopts a holistic approach to public health. Ultimately, the key to eradicating infectious diseases lies in our collective efforts and willingness to adapt to new scientific knowledge and societal changes.