Epidemiologic analysis of a previous outbreak of bubonic plague:The first identified outbreak with bacteriological confirmation in Kobe and Osaka,Japan

Objective:To characterize the case fatality and estimate the symptomatic period of bubonic plague.Methods: Epidemiologic analyses of a previous outbreak of plague in Osaka and Kobe,two major port cities in Japan, from 1899-1900 were performed.In addition to date of onset of symptoms,gender,age and the date of death were extracted from the historical data.The time from onset to death(symptomatic period) was fitted to gamma distribution using the maximum likelihood method.Results:Temporal distribution revealed suspected chains of transmission of the primary pneumonic plague at the late stage of the outbreak.The case fatality of bubonic plague without specific treatment was 83.4%,and the mean time from onset to death was estimated as 4.7 days(95%confidence interval;4.0,5.5).Conclusion:Case fatality of bubonic plague without specific treatment was extremely high.The symptomatic period of bubonic plague appeared to be longer than that of pneumonic plague.

Stability Analysis of Bubonic Plague Model with the Causing Pathogen Yersinia pestis in the Environment

Bubonic plague is a serious bacterial disease, mainly transmitted to human beings and rodents through flea bite. However, the disease may also be transmitted upon the interaction with the infected materials or surfaces in the environment. In this study, a deterministic model for bubonic plague disease with Yersinia pestis in the environment is developed and analyzed. Conditions for existence and stability of the equilibrium points are established. Using Jacobian method disease free equilibrium (DFE) point, E0 was proved to be locally asymptotically stable. The Metzler matrix method was used to prove that the DFE was globally asymptotically stable when R0 < 1. By applying Lyapunov stability theory and La Salles invariant principle, we prove that the endemic equilibrium point of system is globally asymptotically stable when R0 > 1. Numerical simulations are done to verify the analytical predictions. The results show that bubonic plague can effectively be controlled or even be eradicated if efforts are made to ensure that there are effective and timely control strategies.

Single-cell transcriptomics of immune cells in lymph nodes reveals their composition and alterations in functional dynamics during the early stages of bubonic plague

Bubonic plague caused by Yersinia pestis is highly infectious and often fatal.Characterization of the host immune response and its subsequent suppression by Y.pestis is critical to understanding the pathogenesis of Y.pestis.Here,we utilized single-cell RNA sequencing to systematically profile the transcriptomes of immune cells in draining lymph nodes(d LNs)during the early stage of Y.pestis infection.Dendritic cells responded to Y.pestis within 2 h post-infection(hpi),followed by the activation of macrophages/monocytes(Mφs/Mons)and recruitment of polymorphonuclear neutrophils(PMNs)to d LNs at 24 hpi.Analysis of cell-to-cell communication suggests that PMNs may be recruited to lymph nodes following the secretion of CCL9 by Mφs/Mons stimulated through CCR1-CCL9 interaction.Significant functional suppression of all the three innate immune cell types occurred during the early stage of infection.In summary,we present a dynamic immune landscape,at single-cell resolution,of murine d LNs involved in the response to Y.pestis infection,which may facilitate the understanding of the plague pathogenesis of during the early stage of infection.

Imperatives of Health Psychologist in the Control and Management of HIV/AIDS in Sub-Saharan Africa

The paper studied the imperatives of health psychologists in the control and management of HIV/ AIDS. HIV/AIDS is a relatively new disease, but has caused more deaths than any other disease in human history, and there is no known cure yet. Even though, HIV/AIDS is a death sentence, experts agreed that early detection, and early commencement of treatment may prolong the life of the patients, and that early detection may prevent or reduce the transmission of the virus. Early detection, commencement of treatment, and compliance with medical advice are the responsibilities of the health psychologist. This paper therefore, concludes that health psychologist is indispensable in effective control, and management of HIV/AIDS, and so recommends that awareness be created on the roles of health psychologists in this regard, through health education.

Epidemiological features of four human plague cases in the Inner Mongolia Autonomous Region, China in 2019

This study aims to investigate cases of human plague in the Inner Mongolia Autonomous Region (IMAR), China, and to inform the development of plague prevention and control strategies. On 12th of November 2019, two herdsmen from Sunitezuo Banner, Xilingol League were diagnosed with pneumonic plague in Beijing, China. On November 16th, one resident of Xianghuang Banner, Xilingol League was diagnosed with bubonic plague in Huade County Hospital, Ulanqab, China. On 27th of November, one resident of Siziwang Banner was diagnosed with bubonic plague. In total, 78 close contacts were monitored over a period, but none of them developed symptoms. Plague outbreaks in animals had been reported in Sunitezuo Banner, Xianghuang Banner, and Siziwang Banner in 2019. Two of the four cases were related (husband and wife), but not the other two. All the cases may be associated with contact with rodents (hare) or infected fleas. The cases highlight the importance of early identification of plague cases in humans in order to stop further infection. This demonstrates the value of monitoring and ongoing vigilance on endemic diseases, the importance of updating medical training and raising public awareness about infectious diseases that even have not been observed over decades.