新研究顯示，行為改變而非疫苗導致2022年MPOX疫情在男同性戀者中放緩

THURSDAY, Feb. 29, 2024 (HealthDay News) -- A new study reveals that the 2022 outbreak of MPOX among gay and bisexual men began to show signs of slowing down after just a few months, a phenomenon that occurred when only 8% of the high-risk population was vaccinated with MPOX vaccine This occurred in a context where only 81 TP3T high-risk individuals were vaccinated against MPOX.

這項由西雅圖Fred Hutchinson癌症中心的流行病學家Miguel Paredes領導的研究團隊進行的研究，得出了一個引人注目的結論：是同性戀和雙性戀男性的性行為變化，而非疫苗接種，導致了疫情的平息。

“一旦認識到MPOX流行，在美國推出疫苗接種之前，男性同性性行為群體的行為改變就會導致北美（傳播率）急劇下降，”研究報告中如此總結。Paredes的團隊於2月29日在學術期刊《細胞》上發表了他們的研究結果。

According to the U.S. Centers for Disease Control and Prevention, the 2022 outbreak of MPOX (formerly known as monkeypox) in the United States involved 31,698 known cases and 56 deaths. Globally, the outbreak involves nearly 93,500 cases. mpox is spread primarily through skin-to-skin contact, with outbreaks in Europe and the U.S. focused on men who have sex with men. cases were first detected in May 2022, and the outbreak reached its peak in August. The U.S. Food and Drug Administration (FDA) has approved a vaccine against the disease in 2019 and has been rolling it out to high-risk populations since the outbreak.

In the new analysis, Paredes' team used sophisticated computer modeling to track the origin and spread of the MPOX variant across the U.S. during the outbreak. They noted that once people in the gay community became aware of the danger, many quickly changed their behavior and had sex with fewer partners.

In August, just a few months after it was first reported in the population, MPOX transmission began to slow, even though the vaccine had not yet reached most high-risk populations. Paredes' team noted, "Mpox transmission in North America began to decline before more than 10% of high-risk people in the U.S. acquired vaccine-induced immunity."

Speaking to the New York Times, this supports the notion that public health messaging "can be really effective in controlling epidemics, even as we wait for products like vaccines to become available."

The study also found that cases were spreading in high-risk neighborhoods long before they were officially reported by public health authorities. This underscores the importance of being vigilant about emerging diseases. Evolutionary biologist Trevor Bedford says doing so can help stop outbreaks and epidemics sooner rather than later.

Virginia Pitzer is an epidemiologist at the Yale School of Public Health. Looking back at the results of the study, she emphasizes that vaccines still play a crucial role in containing the spread of disease. While the behavior of gay men may have slowed the spread of pox in the short term, it's not clear whether behavioral changes would have kept the disease away forever without the vaccine.

"As we've seen in the New Crown outbreak, behavior change can only last for so long," she said.

More information: Learn more about MPOX at the U.S. Centers for Disease Control and Prevention.

Sources: the Cell, February 29, 2024; The New York Times.