Ecologic and Sociodemographic Factors Associated with Seroprevalence of Rickettsia in Yucatan, Mexico

Background: Rickettsioses disproportionately affect vulnerable populations and are frequently misdiagnosed as other febrile illnesses in Yucatan, the Mexican state with the greatest diversity of Rickettsia spp. Although significant seroprevalence has been reported in rural communities, the last population-based study was conducted over two decades ago, despite environmental and social changes that have likely increased transmission risk. This study aimed to estimate the seroprevalence of spotted fever group (SFG) and typhus group (TG) of Rickettsia in an endemic area of southeastern Mexico. Methods: A cross-sectional analytical study was conducted among 390 participants. Indirect immunofluorescence was used to detect IgG antibodies against SFG and TG of Rickettsia. Sociodemographic characteristics of participants, along with environmental and community-level variables from their regions of residence, were analyzed. Results: The overall seroprevalence of both Rickettsia groups was 31.2%. Higher maximum temperatures were associated with an increase in Rickettsia seroprevalence (PR = 4.18; 95% CI: 3.40–5.14), while higher population density was associated with a decrease in seroprevalence (PR = 0.97; 95% CI: 0.96–0.98). Conclusions: Rickettsia seroprevalence in Yucatan remains high and is shaped by both environmental and demographic factors. These findings highlight the need to strengthen surveillance and prevention strategies that integrate ecological and social determinants within a One Health framework.