Impact of Temperature and Rainfall on Typhoid/Paratyphoid Fever in Taizhou, China: Effect Estimation and Vulnerable Group Identification

The impact of temperature and rainfall on the occurrence of typhoid/paratyphoid fever are not fully understood. This study aimed to characterize the effect of daily ambient temperature and total rainfall on the incidence of typhoid/paratyphoid in a sub-tropical climate city of China and to identify the vulnerable groups for disease prevention. Daily notified typhoid/paratyphoid fever cases and meteorological data for Taizhou from 2005 to 2013 were extracted from the National Notifiable Disease Surveillance System and the Meteorological Data Sharing Service System, respectively. Distributed lag nonlinear model was used to quantify the association between daily mean temperature, total rainfall, and typhoid/paratyphoid fever. Subgroup analyses by gender, age, and occupation were conducted to identify the vulnerable groups. A total of 625 typhoid fever cases and 1,353 paratyphoid fever cases were reported during the study period. An increased risk of typhoid fever was detected with the increase of temperature (Each 2°C rise resulted in 6%, 95% [confidence interval] CI: 2–10 increase in typhoid cases), while the increased risk was associated with the higher temperature for paratyphoid (the highest cumulative risk of temperature was 33.40 [95% CI: 12.23–91.19] at 33°C). After the onset of mild precipitation, the relative risk of typhoid fever increased in a short-lasting and with a 13–26 days delay, and the risk was no significant after the continuous increase of precipitation (the highest cumulative risk of rainfall was 24.96 [95% CI: 4.54–87.21] at 100 mm). Whereas the risk of paratyphoid fever was immediate and long lasting, and increase rapidly with the increase of rainfall (each 100 mm increase was associated with 26% increase in paratyphoid fever cases). Significant temperature-typhoid/paratyphoid fever and rainfall-typhoid/paratyphoid fever associations were found in both genders and those aged 0–4 years old, 15–60 years old, farmers, and children. Characterized with a lagged, nonlinear, and cumulative effect, high temperature and rainfall could increase the risk of typhoid/paratyphoid fever in regions with a subtropical climate. Public health interventions such as early warning and community health education should be taken to prevent the increased risk of typhoid/paratyphoid fever, especially for the vulnerable groups.

On the diagnostic value of blood culture on distilled water in typhoid fever

There is no need to prove the importance of recognizing typhoid diseases as early as possible. The most important method for meeting this need is blood culture. While it is almost impossible to make a diagnosis in the first days of the disease by other methods (Widals reaction and sowing stool), sowing blood with typhoid fever in the first 7 days, and with paratyphoid fever for the first time 3-4 days, gives almost 100% positive results.

Genome-wide analysis provides a deeper understanding of the population structure of the Salmonella enterica serotype Paratyphi B complex in Bangladesh

The Salmonella enterica serotype Paratyphi B complex causes a wide range of diseases, from gastroenteritis to paratyphoid fever, depending on the biotypes Java and sensu stricto. The burden of Paratyphi B biotypes in Bangladesh is still unknown, as these are indistinguishable by Salmonella serotyping. Here, we conducted the first whole-genome sequencing (WGS) study on 79 Salmonella isolates serotyped as Paratyphi B that were collected from 10 nationwide enteric disease surveillance sites in Bangladesh. Placing these in a global genetic context revealed that these are biotype Java, and the addition of these genomes expanded the previously described PG4 clade containing Bangladeshi and UK isolates. Importantly, antimicrobial resistance (AMR) genes were scarce amongst Bangladeshi S. Java isolates, somewhat surprisingly given the widespread availability of antibiotics without prescription. This genomic information provides important insights into the significance of S. Paratyphi B biotypes in enteric disease and their implications for public health.

Ancient DNA Study in Medieval Europeans Shows an Association Between HLA-DRB1*03 and Paratyphoid Fever

Outbreaks of infectious diseases repeatedly affected medieval Europe, leaving behind a large number of dead often inhumed in mass graves. Human remains interred in two burial pits from 14th century CE Germany exhibited molecular evidence of Salmonella enterica Paratyphi C (S. Paratyphi C) infection. The pathogen is responsible for paratyphoid fever, which was likely the cause of death for the buried individuals. This finding presented the unique opportunity to conduct a paratyphoid fever association study in a European population. We focused on HLA-DRB1*03:01 that is a known risk allele for enteric fever in present-day South Asians. We generated HLA profiles for 29 medieval S. Paratyphi C cases and 24 contemporaneous controls and compared these to a modern German population. The frequency of the risk allele was higher in the medieval cases (29.6%) compared to the contemporaneous controls (13%; p = 0.189), albeit not significantly so, possibly because of small sample sizes. Indeed, in comparison with the modern controls (n = 39,689; 10.2%; p = 0.005) the frequency difference became statistically significant. This comparison also suggested a slight decrease in the allele’s prevalence between the medieval and modern controls. Up to now, this is the first study on the genetic predisposition to Salmonella infection in Europeans and the only association analysis on paratyphoid fever C. Functional investigation using computational binding prediction between HLA variants and S. Paratyphi and S. Typhi peptides supported a reduced recognition capacity of bacterial proteins by DRB1*03:01 relative to other common DRB1 variants. This pattern could potentially explain the disease association. Our results suggest a slightly reduced predisposition to paratyphoid fever in modern Europeans. The causative allele, however, is still common today, which can be explained by a trade-off, as DRB1*03:01 is protective against infectious respiratory diseases such as severe respiratory syndrome (SARS). It is thus possible that the allele also provided resistance to corona-like viruses in the past.

Single cell analyses reveal distinct adaptation of typhoidal and non-typhoidal Salmonella enterica serovars to intracellular lifestyle

Salmonella enterica is a common foodborne, facultative intracellular enteropathogen. Human-restricted typhoidal S. enterica serovars Typhi (STY) or Paratyphi A (SPA) cause severe typhoid or paratyphoid fever, while many S. enterica serovar Typhimurium (STM) strains have a broad host range and in human hosts usually lead to a self-limiting gastroenteritis. Due to restriction of STY and SPA to primate hosts, experimental systems for studying the pathogenesis of typhoid and paratyphoid fever are limited. Therefore, STM infection of susceptible mice is commonly considered as model system for studying these diseases. The type III secretion system encoded by Salmonella pathogenicity island 2 (SPI2-T3SS) is a key factor for intracellular survival of Salmonella. Inside host cells, the pathogen resides within the Salmonella-containing vacuole (SCV) and induces tubular structures extending from the SCV, termed Salmonella-induced filaments (SIF). This study applies single cell analyses approaches, which are flow cytometry of Salmonella harboring dual fluorescent protein reporters, effector translocation, and correlative light and electron microscopy to investigate the fate and activities of intracellular STY and SPA. The SPI2-T3SS of STY and SPA is functional in translocation of effector proteins, SCV and SIF formation. However, only a low proportion of intracellular STY and SPA are actively deploying SPI2-T3SS and STY and SPA exhibited a rapid decline of protein biosynthesis upon experimental induction. A role of SPI2-T3SS for proliferation of STY and SPA in epithelial cells was observed, but not for survival or proliferation in phagocytic host cells. Our results indicate that reduced intracellular activities are factors of the stealth strategy of STY and SPA and facilitate systemic spread and persistence of the typhoidal Salmonella.

Monitoring the incidence and causes of diseases potentially transmitted by food in Australia: Annual report of the OzFoodNet network, 2013–2015

This report summarises the incidence of diseases potentially transmitted by food in Australia, and details outbreaks associated with food that occurred during 2013–2015. OzFoodNet sites reported an increasing number of notifications of 12 diseases or conditions vthat may be transmitted by food (botulism; campylobacteriosis; cholera; hepatitis A; hepatitis E; haemolytic uraemic syndrome (HUS); listeriosis; Salmonella Paratyphi (paratyphoid fever) infection; salmonellosis; shigellosis; Shiga toxin-producing Escherichia coli (STEC) infection; and Salmonella Typhi (typhoid fever) infection), with a total of 28,676 notifications received in 2013; 37,958 in 2014; and 41,226 in 2015. The most commonly-notified conditions were campylobacteriosis (a mean of 19,061 notifications per year over 2013–2015) and salmonellosis (a mean of 15,336 notifications per year over 2013–2015). Over these three years, OzFoodNet sites also reported 512 outbreaks of gastrointestinal illness caused by foodborne, animal-to-person or waterborne disease, affecting 7,877 people, and resulting in 735 hospitalisations and 18 associated deaths. The majority of outbreaks (452/512; 88%) were due to foodborne or suspected foodborne transmission. The remaining 12% of outbreaks were due to waterborne or suspected waterborne transmission (57 outbreaks) and animal-to-human transmission (three outbreaks). Foodborne and suspected foodborne outbreaks affected 7,361 people, resulting in 705 hospitalisations and 18 deaths. Salmonella was the most common aetiological agent identified in foodborne outbreaks (239/452; 53%), and restaurants were the most frequently-reported food preparation setting (211/452; 47%). There were 213 foodborne outbreaks (47%) attributed to a single food commodity during 2013–2015, with 58% (124/213) associated with the consumption of eggs and egg-based dishes.

STUDYING THE HISTORY OF THE DEVELOPMENT OF THE HEALTHCARE SYSTEM IN UZBEKISTAN DURING THE YEARS OF INDEPENDENCE

The article briefly highlights the history of the study of the health problem by Uzbek scientists in a certain period of time. The works of the authors are divided into groups based on their quality, nature and focus. Monographic and dissertation research is especially highlighted. Used methods of chronological and comparative analysis, particular attention is paid to the study of orientalists of Uzbekistan and publications of foreign authors. It is recognized that as a result of the implementation of the results of dissertation research by individual authors, there is an optimization of the structure of health care authorities and a decrease in the level of disease in the population. Over the years of independence, a health care reform program has been implemented. Much has been done to improve its quality and culture of timeliness and efficiency. A network of urgent emergency care, rural medical outpatient clinics and city polyclinics, multidisciplinary specialized clinics, scientific centers has been created. Medical care for women and children of the country is provided at the level of world standards, personnel training is carried out in 14 medical universities and one pharmaceutical institute, in 85 medical colleges. Advanced training and retraining of medical personnel is carried out in universities and an advanced training institute. At present, it is one of the most important branches of the country’s national economy. As a result of socio-economic and medical measures in Uzbekistan, medical care has become universal and publicly available, such dangerous diseases as cholera, plague, smallpox, parasitic typhus, trachoma have been eliminated, and the incidence of many others has been reduced. Over the past 10 years, the incidence of the population with such socially dangerous ailments as congenital defects by 32.4%, infectious diseases by 40%, the incidence of the upper respiratory tract has decreased by 4.2 times. The incidence of diphtheria, paratyphoid fever, poliomyelitis, malaria has been completely eradicated [1]. The health care system employs about 650 thousand people (this is almost 10 percent of the able-bodied population of the republic), including more than 84 thousand doctors and 500 thousand paramedical workers. An extensive network of medical institutions in Uzbekistan is capable of providing the necessary medical and preventive care to the entire population.

Temperature and Risk of Infectious Diarrhea: A Systematic Review and Meta-analysis

There are many studies that have explored the relationship between temperature and the spread of infectious diarrhea (ID), but the results obtained are inconsistent. It is necessary to systematically evaluate the impact of temperature on the incidence of ID. ID is an intestinal infectious disease including cholera, typhoid and paratyphoid fever, bacterial and amebic dysentery, and other infectious diarrhea. This study is based on the PRISMA statement to report this systematic review. We conduct literature searches from CNKI, VIP databases, CBM, PubMed, Web of Science, Cochrane Library and other databases. The number registered in PROSPERO is CRD42021225472. Finally, after searching a total of 4,915 articles in the database and references, a total of 27 studies were included. The number of people involved exceeded 7.07 million. The overall result demonstrated when the temperature rises, there is a significant increase in infectious diarrhea (RRcumulative=1.42, 95%CI:1.07–1.88, RRsingle−day=1.08, 95%CI:1.03–1.14). Subgroup analysis found that the cumulative effect of temperature on the bacillary dysentery group and other diarrhea groups. The result of the single-day effect subgroup analysis was similar to the result of the cumulative effect. And the sensitivity analysis proves that the above results were robust. This systematic review and meta-analysis support that temperature will increase the risk of ID, which is helpful for ID prediction and early warning in the future.