A new lipid nanoparticle could make mRNA vaccines more effective and potentially lower the cost per dose. New research suggests an mRNA influenza vaccine delivered with the new particle could generate the same immune response as mRNA delivered by standard nanoparticles, but at around 1/100 the dose.

This study reports the first molecular evidence of potentially zoonotic Rickettsia species in ticks collected from domestic dogs in Malawi, marking a significant advancement in understanding tick-borne disease risks in southeastern Africa. Researchers from Hokkaido University and Lilongwe University of Agriculture and Natural Resources screened 209 dog blood samples and 259 tick samples using molecular techniques. While no Rickettsia DNA was detected in dog blood, the analysis revealed infection rates of 2.5% in Rhipicephalus linnaei ticks and 6.3% in Haemaphysalis elliptica ticks.

The study identified three Rickettsia species: Rickettsia conorii subsp. conorii (the causative agent of Mediterranean spotted fever), Rickettsia massiliae, and Rickettsia rhipicephali. Notably, this is the first report of R. massiliae and R. rhipicephali in southern Africa, indicating a geographical expansion of these pathogens. The findings highlight the important role that dog-associated ticks may play in maintaining and transmitting rickettsial pathogens with zoonotic potential.

Given the close association between dogs and humans in Malawi, where people often share living spaces with their pets, these findings underscore the need for integrated One Health surveillance approaches. The research team recommends future studies include human serosurveys and public awareness campaigns to better assess the true burden of rickettsial infections in the region.