Changing epidemiologic patterns of typhus group rickettsiosis and scrub typhus in China, 1950-2022.

OBJECTIVES: We conducted a systematic analysis of the notifiable rickettsial diseases in humans in China during 1950-2022. METHODS: We utilized descriptive statistics to analyze the epidemiological characteristics, clinical manifestations, and diagnostic characteristics of typhus group rickettsiosis (TGR) and scrub typhus (ST) cases. RESULTS: Since the 1950s, there have been variations in the incidence rate of TGR and ST in China, with a downtrend for TGR and an uptrend for ST. The South became a high-incidence area of TGR, whereas the North was previously the high-incidence area. ST cases were concentrated in the South and the geographic area of ST spread northward and westward. The seasonality of TGR and ST were similar in the South but distinct in the North. Most TGR and ST cases were reported by county-level medical institutions, whereas primary institutions reported the least. Delayed diagnosis was associated with fatal outcomes of TGR and ST. Cases in low-incidence provinces, confirmed by laboratory tests and reported from county/municipal-level institutions had higher odds of delayed diagnoses. CONCLUSIONS: Our study revealed significant changes in the epidemiological characteristics of TGR and ST in China, which can provide useful information to enhance the control and prevention strategies of rickettsial diseases in China.

La Valentine disease: An outbreak of exanthematic typhus in Marseille, France, in 1810.

BACKGROUND: Exanthematic typhus was highly frequent in the early 19th century among military troops and prisoners and at hospitals. METHODS: Based on old reports, we describe an outbreak in a village, in Southern France, in 1810. RESULTS: Twenty-eight cases were identified, over a period of 10 days following the death of the index case, in a soldier. Symptoms included notably persistent constant fever, myalgia and headaches, gastro-intestinal symptoms, prostration and stupor. Three patients suffered delirium and nine died (31.0%). Overall, symptoms persisted for 13-14 days. A total of 16 cases were secondary to contacts with the index case, and 10 cases were in house-hold contacts of secondary cases. Five familial clusters were described. CONCLUSION: This data suggest that exanthematic typhus outbreaks among civilian populations also occurred outside the context of hospitals, in link with introduction of the disease by prisoners or soldiers.

The history of louse-borne typhus and geomedizine.

The experience of World War I made popular the concept of medical geography (geomedicine in English, geomedizine in German), which became part of Nazism's philosophy of national welfare, safety, and solidarity. The Nazis used it to create propaganda to show some groups as rats, vermin, and Untermenschen (subhumans). In this way, more than 10 million people were killed under the Nazi regime: 6 million Jews, plus more than 5 million Gypsies, Jehovah's Witnesses, and other individuals who were not part of the German theory of "master race." The Germans' fear of typhus that spread in the Wehrmacht was so immense that during the occupation, Polish doctors used this phobia to organize a resistance movement. Contemporarily, the scope of geographic medicine encompasses the following research areas: spatial differentiation of disease incidents and the process of disease diffusion, geographic inequalities in the population's health level, and morbidity determinants among the inhabitants of developing countries. In the first half of the 19th century, it played an essential role in the activities aimed against epidemics of infectious diseases, including louse-borne typhus (epidemic typhus), cholera, and typhoid, linking these diseases to cultural determinants. Under the influence of this idea, the concept of doctor-hygienist emerged, and social medicine began to evolve.

Emerging bacterial infectious diseases/pathogens vectored by human lice.

Human lice have always been a major public health concern due to their vector capacity for louse-borne infectious diseases, like trench fever, louse-borne relapsing fever, and epidemic fever, which are caused by Bartonella quintana, Borrelia recurrentis, and Rickettsia prowazekii, respectively. Those diseases are currently re-emerging in the regions of poor hygiene, social poverty, or wars with life-threatening consequences. These louse-borne diseases have also caused outbreaks among populations in jails and refugee camps. In addition, antibodies and DNAs to those pathogens have been steadily detected in homeless populations. Importantly, more bacterial pathogens have been detected in human lice, and some have been transmitted by human lice in laboratories. Here, we provide a comprehensive review and update on louse-borne infectious diseases/bacterial pathogens.

[Epidemiological characteristics of typhus in China, 1950-2021].

Objective: To analyze the epidemiological characteristics of typhus in China from 1950 to 2021, and discuss the challenges in typhus prevention and control in China and suggest future prevention and control strategies. Methods: Based on the reported data of typhus from 1950 to 2021 in China from the Infectious Disease History Database of China Public Health Science Data Center and the National Notifiable Infectious Disease Reporting Information System of Chinese Center for Disease Control and Prevention, we conducted a descriptive statistical analysis. Mann-Kendall test and circular distribution method were used to analyze the incidence, mortality and case fatality of typhus to reveal the temporal, spatial and population distributions and diagnosis of typhus in China. Results: From 1950 to 2021, a total of 452 965 typhus cases and 7 339 typhus deaths were reported in China, with the cases numbers exceeding 10 000 in 14 years of the 1950s, 1960s and 1980s, respectively. Since 1990s, the reported cases and incidence rate of typhus have decreased dramatically and the most cases were sporadic. However, the reported typhus cases in Anhui, Hubei, Hunan Provinces showed significant uptrends. Although typhus could occur all the year round, but the seasonality was observed with the incidence mainly in summer and autumn. For different provinces from the north to the south, the peaks of typhus' monthly incidence tended to shift to earlier dates. The male to female ratio of the cases was 1.01∶1 (18 529∶18 366). However, more cases occurred in women in recent years. The cases aged ≤9 years accounted for the highest proportion (18.9%), but the number of cases aged ≥50 years showed an upward trend. Most cases were farmers with the proportion increasing year by year. Moreover, the cases in students and scattered-living children also accounted for relatively higher proportions. The median of the interval between onset and diagnosis of typhus was 6 days. Most cases were clinically diagnosed, while the proportion of laboratory-confirmed cases was low and most laboratory cases were confirmed by Well-Felix reaction. Conclusions: Although the incidence and mortality of typhus in China has decreased significantly, the risk for local typhus outbreaks still exists. The prevention and control of typhus still face many challenges. It is indispensable to strengthen the pathogen detection and surveillance for typhus in China.

Increased Seroprevalence of Typhus Group Rickettsiosis, Galveston County, Texas, USA.

Whether increases in typhus group rickettsiosis in Galveston County, Texas, USA, are caused by increased recognition or true reemergence is unclear. We conducted a serosurvey that demonstrated Rickettsia typhi antibodies increased from 1.2% in 2013 to 7.8% in 2021 (p<0.001). These findings support pathogen reemergence rather than enhanced recognition alone.

The contributions of James Carmichael Smyth, Archibald Menzies and Robert Jackson to the treatment of typhus in royal naval vessels in the late 18th century.

In late 18th century Britain, typhus fever plagued the mass mobilisation of soldiers and posed a significant challenge to physicians of the time. Epidemic typhus was spread through highly infectious faeces of infected lice and carried a high mortality in patients and healthcare staff alike. Physicians James Carmichael Smyth (1741-1821) and Archibald Menzies (1754-1842) theorized that typhus fever was caused by infection of human exhalation. They trialled the use of vapourised nitrous acid to fumigate patients, their clothes and their bedspace, with apparent success. Despite this, typhus fever continued to ravage deployments of soldiers into the early 19th century, stimulating the continuing evolution of the understanding of typhus and its treatment.

Lice and lice-borne diseases in humans in Africa: A narrative review.

Lice are host-specific insects. Human lice include Pediculus humanus (body lice) which are known to be vectors of serious human bacterial infectious diseases including epidemic typhus, relapsing fever, trench fever and plague; Pediculus humanus capitis (head lice) that frequently affect children; and Pthirus pubis, commonly known as crab lice. In Africa, human infections transmitted by lice remained poorly known and therefore, underestimated, perhaps due to the lack of diagnostic tools and professional knowledge. In this paper we review current knowledge of the microorganisms identified in human lice in the continent of Africa, in order to alert health professionals to the importance of recognizing the risk of lice-related diseases.

Renewed Risk for Epidemic Typhus Related to War and Massive Population Displacement, Ukraine.

Epidemic typhus, caused by Rickettsia prowazekii bacteria and transmitted through body lice (Pediculus humanus corporis), was a major public health threat in Eastern Europe as a consequence of World War II. In 2022, war and the resulting population displacement in Ukraine risks the return of this serious disease.

Typhus works of Rudolf Weigl, PhD, Ludwik Fleck, MD, and Eugeniusz Lazowski, MD, against the Nazis.

Typhus has been present in Central Europe and Russia since the 19th century, but it was not until 1918 that it became an epidemic problem in Poland. Poverty, general devastation, unsanitary living conditions, and the extensive spread of the disease forced the Polish government to organize effective measures to improve the population's health. One such measure was the establishment of a typhus research center in Lviv. The center was led by Rudolf Weigl, who in the 1930s succeeded in elaborating a clinically effective vaccine. In September 1939, when the Germans invaded Poland, the problem of typhus returned, primarily due to the ghettos where the Nazis confined Jews in poor, crowded, and unsanitary conditions. Later, in 1941 when Nazis tried to invade the Soviet Union (where typhus was endemic), the typhus vaccine-the work of Weigl and Ludwik Fleck (also an employee of the Lviv institute)-was in high demand. The Germans feared typhus due to its persistence and speed of spread. The Nazi typhus phobia was also used by some Polish doctors who took advantage of this disease to protect their patients from being deported or located in camps. An example of such a doctor was Eugeniusz Lazowski, who even organized a "false pandemic" to save the local population.

Typhus Disease in Iran during the Qajar Period (1725 to 1925 AD); a Brief Historical Review.

Typhus is an acute febrile disease caused by a series of bacteria called Rickettsia that is transmitted by insects such as lice, fleas, and ticks. This disease has appeared several times in Iran and caused many casualties. There were some therapeutic measures taken by European physicians in Tehran and medical graduates of the Dar al-Fonun school or expatriates who had studied medical courses in Western countries, even though the taken steps were not enough. Due to the lack of sanitation and cleaning products after the outbreak of World War I in March 1917 and its synchronization with the swift outbreak of Typhus in 1918, heavy casualties followed. In this study, we first examine the prevalence of Typhus in the Qajar dynasty in Iran, and will then focus on the pathological importance of this disease history in Iran. After that, we will study the role of Typhus prevalence and World War I in the Persian famine, malnutrition, and food poverty. Moreover, we investigated the role that this great war had in strengthening the spread of this disease and its role in the death of many Iranian people.

Non-Pharmaceutical Interventions and Military Hygiene at the United States Military Academy between 1890 and 1910.

INTRODUCTION: Military installations are at increased risk for the transmission of infectious disease. Personnel who live and train on military installations live and train near one another facilitating disease transmission. An understanding of historical sanitation and hygiene can inform modern practices. This is especially pertinent considering the continuing rise of variants of infectious diseases, such as the recent pandemic of the 2019 severe acute respiratory syndrome coronavirus 2. In this article, we review the rise and decline of infectious disease at the United States Military Academy (USMA) during the period spanning 1890 through 1910, and the public health interventions used to combat disease spread. MATERIALS AND METHODS: Primary data regarding cadet illness were acquired from the historical archives of the USMA. These included annual reports, clinical admission records, casualty ledgers, and sanitation reports. Unpublished documents from the medical history of USMA provide periodic trends of health among cadets because of infectious disease. RESULTS: Between 1890 and 1910, the USMA at West Point was confronted with cases of influenza, measles, mumps, scarlet fever, smallpox, typhus, and malaria. In response, a series of non-pharmaceutical interventions (NPIs) were instituted to curb the spread of infectious disease. These interventions most likely proved effective in suppressing the transmission of communicable diseases. The most common and arguably the most effective NPI was the physical separation of the sick from the well. CONCLUSIONS: The USMA experience mirrored what was occurring in the larger U.S. Army in the early 20th century and may serve as a model for the application of NPIs in response to modern infectious diseases resulting from novel or unknown etiologies.

Avidity of IgG to Rickettsia prowazekii and the presence of specific IgM in blood sera for retrospective analysis of the 1998 epidemic typhus outbreak in Russia.

The authors applied a new methodological approach based not only on the study of IgM/IgG to Rickettsia prowazekii in sera, but also on the estimation of the avidity index of specific IgG. The data allowed the authors to draw new conclusions about the 1998 epidemic typhus outbreak in Russia.

John Donne, Spanish Doctors and the epidemic typhus: fleas or lice?

We describe the infections that appeared in the life and work of John Donne (1572-1631), the English metaphysical poet, mainly the exanthematic typhus that suffered and gave arise to his work Devotions upon emergent occasions, and several steps in my sickness. We discuss the vector of transmission of this disease, in comparison of other infections in that period, that Donne´s scholars have related to the flea without mentioning the body louse, the true vector of the exanthematic typhus. Likewise, we mention the exanthematic typhus´s symptoms in his Devotions in comparison with the Luis de Toro´s or Alfonso López de Corella´s works, Spanish doctors in those times and the first doctors in write books about the disease, and the singular treatment of pigeon carcasses on the soles of the feet in English Doctors but not in Spanish Doctors.

Trends in clinical diagnoses of typhus group rickettsioses among a large U.S. insurance claims database.

Typhus group rickettsioses (TGRs) are vector-borne diseases that include murine typhus (Rickettsia typhi) and epidemic typhus (R. prowazekii). Twentieth-century public health interventions led to dramatic decreases in incidence; little is known about the contemporary TGR prevalence because neither disease is nationally notifiable. We summarized administrative claims data in a commercially insured population to examine trends in TGR medical encounters. We analysed data from 2003 to 2016 IBM® MarketScan® Commercial Databases to identify persons with inpatient or outpatient visits with an International Classification of Diseases, Ninth or Tenth Revision, Clinical Modification TGR-specific code. We summarized epidemiologic characteristics associated with incident diagnosis. We identified 1,799 patients diagnosed with a TGR. Patients resided in 46 states, and most were female (n = 1,019/1,799; 56.6%); the median age was 42 years (range: 0-64 years). Epidemic typhus (n = 931/1,799; 51.8%) was the most common TGRs, followed by murine typhus (n = 722/1,799; 40.1%). The majority of TGR patients were diagnosed in an outpatient setting (n = 1,725/1,799; 95.9%); among hospitalized patients, the majority received a murine typhus diagnosis (n = 67/74; 90.5%). TGRs are rarely diagnosed diseases. More patients were diagnosed with epidemic than murine typhus, even though R. prowazekii transmission requires body louse or flying squirrel exposure. Patients from all geographic regions were diagnosed with murine and epidemic typhus, despite historically recognized ranges for these diseases. The epidemiologic misalignment of insurance claims data versus historic TGRs data highlights the challenges of finding appropriate alternative data sources to serve as a proxy when national surveillance data do not exist.

Climate factors driven typhus group rickettsiosis incidence dynamics in Xishuangbanna Dai autonomous prefecture of Yunnan province in China, 2005-2017.

BACKGROUND: Typhus group rickettsiosis (TGR), which is a neglected vector-borne infectious disease, including epidemic typhus and endemic typhus. We explored the lag effects and nonlinear association between meteorological factors and TGR incidence in Xishuangbanna Dai autonomous prefecture from 2005 to 2017, China. METHODS: A Poisson regression with a distributed lag nonlinear model (DLNM) was utilized to analyze TGR cases data and the contemporaneous meteorological data. RESULTS: A J-shaped nonlinear association between weekly mean temperature and TGR incidence was found. The cumulative exposure to weekly mean temperature indicated that the RR increased with the increment of temperature. Taking the median value as the reference, lower temperatures could decrease the risk of TGR incidence, while higher temperatures could increase the risk of TGR incidence and last for 21 weeks. We also found a reversed U-shaped nonlinear association between weekly mean precipitation and TGR incidence. Precipitation between 5 mm and 13 mm could increase the risk of TGR incidence. Taking the median value as the reference, no precipitation and lower precipitation could decrease the risk of TGR incidence, while higher precipitation could increase the risk of TGR incidence and last for 18 weeks. CONCLUSIONS: The prevention and control measures of TGR should be implemented according to climatic conditions by the local government and health departments in order to improve the efficiency.

On Courtroom Dramas and Plot Twists: Typhus in Eighteenth-Century London.

This article applies the model developed in Charles Rosenberg's seminal article "What is an Epidemic?" to typhus outbreaks in eighteenth-century London. That framework remains valuable for understanding contagious disease in early modernity by helping to highlight the structure of responses to epidemics. So-called "Jail Fever" outbreaks are especially instructive, in part because the most notorious of these epidemics were small affairs when compared to the larger pandemics that Rosenberg explored. Considering that they accounted for relatively few deaths, historians must answer why they caused such a stir. Whereas the raw body count often drives development of narratives about epidemics, eighteenth-century typhus epidemics often hinged more on who died and where than how many. Typhus ravaged poor and working class communities throughout the period. However, even significant spikes in mortality occurring in poor neighborhoods often failed to trigger proclamations of epidemics. Some deaths mattered more than others in this regard, suggesting that qualitative criteria may have played a greater role than quantitative criteria when it came to identifying which events registered as epidemics in the eighteenth century.

Epidemiological characteristics and spatiotemporal patterns of typhus group rickettsiosis at the county level in China, 2005-2017.

OBJECTIVE: To explore the epidemiological characteristics and spatiotemporal patterns of typhus group rickettsiosis (TGR) in mainland China. METHODS: A chi-squared test was used to compare the differences in the age and occupation distributions across the different years. Time-series analyses, spatial clustering analyses, and spatiotemporal scan statistics were used to detect the spatiotemporal patterns of the TGR incidence. RESULTS: A total of 29,211 TGR cases were collected. Of these cases, 63.1% occurred from May to October, and 88.4% occurred in individuals between 0 and 59 years old. There was a significant spatial TGR heterogeneity from 2005 to 2017. The hotspots were located mainly in the southwestern, southern, and circum-Bohai Sea regions of northern China. Eighteen spatiotemporal clusters were observed using Kulldorff's space-time scan statistic, and the primary cluster included three counties, Jinghong city, Menghai county, and Mengla county. CONCLUSIONS: TGR is widely distributed in China, and it is a serious threat to public health. The hotspots were located mainly in the southwestern, southern, and circum-Bohai Sea regions of northern China, and the primary spatiotemporal cluster showed a trend shifting from circum-Bohai Sea regions to the southwestern regions. Targeted interventions should be executed in high-risk regions for precise prevention and control.