Typhoid Disease Research Articles

Therapeutic Plants Used for Typhoid Fever Treatment in Kaduna State Nigeria

For ages, medicinal plants play a significant role in the effective, affordable, and safe healthcare system. Medicinal plants continue to play an important role in Nigeria's healthcare system, which serves more than 70% of the country's population. For pharmaceutical exploration and conservation, it is important to document the use of medicinal plants in a specific region across time. The study's goal was to find out which plants were used to treat typhoid illness in Kaduna state. The in-depth interview guide was utilized in conjunction with an expert method and non-random probability sampling. The study discovered and recorded 31 plant species from 25 families that are used by Kaduna residents to cure typhoid diseases. Plants with a 0.45 value of relative frequency citation were documented. The highest relative frequency of citation (0.9) and fidelity level (90%) are found in Garcinia mangostana, Senna alata, Moringa oleifera, and Hibiscus sabdariffa, respectively. In Nigeria, traditional medicinal knowledge is guarded by elderly people. The study discovered plant species that could be used as a potential source of anti typhoid in Nigeria.

Spatial Variability of Typhoid Disease Incidences in Uganda Using Geographically Weighted Regression Approach

The spatial variability of typhoid disease incidences has not been accounted for, most especially in developing countries, which makes its surveillance inefficient and expensive. This research aimed at (i) exploring possible risk factors of typhoid disease and (ii) accounting for spatial variability of typhoid disease incidences using GWR approach. The research first explored possible risk factors of typhoid disease using global regression-Ordinary Least Squares (OLS). Geographically Weighted Regression (GWR) model was used to account for spatial variability of typhoid disease incidences. Moran’s Index was used to confirm spatial patterns in the data. The research revealed that; poor handwashing practice, rainfall and poor drainage (floods effect) were responsible for spatial variability of typhoid disease locally (P<0.05). GWR model revealed that poor handwashing practice was mainly responsible for typhoid disease occurrences in Northern, Northwestern and Mid-central parts of the country while excessive rainfall was mainly responsible for occurrence of the disease in the Eastern and Western regions. Poor drainage was mainly influencing disease occurrences in Eastern and Southwestern parts of the country. In the analysis, GWR model performed better than global OLS model (R-squared=0.37, R-squared=0.25 respectively). A combination of poor handwashing practice, excessive rainfall and poor drainage accounts for spatial variability of typhoid disease incidences in Uganda. This knowledge is very essential for surveillance teams to (i) enforce preventive measures, (ii) prepare for outbreaks and (iii) make targeted interventions to eventually reduce operational costs.

Water infrastructure and health in U.S. cities

Between 1900 and 1930 typhoid fever and other waterborne diseases were largely eradicated from U.S. cities. This achievement required a mix of technological, scientific, economic, and bureaucratic innovations. This article examines how the interaction of those forces influenced water and sanitary infrastructure provision during the 19th and early 20th centuries. I document a sharp link between infrastructure investments and declines in waterborne disease and discuss how that relationship informs the methodological approaches one should use to assess the impact of sanitary investments on urban development. Finally, I review the literature on the social returns to eliminating the threat of waterborne disease. The evidence suggests the benefits of infrastructure investment far exceeded the costs.

Toxicological Profile of the Aqueous Extract of Tectona grandis L.F. (Verbenaceae) Leaves: A Medicinal Plant Used in the Treatment of Typhoid Fever in Traditional Cameroonian Medicine

Tectona grandis (T. grandis) is a medicinal plant widely used in Cameroon to treat typhoid fever and several other diseases. Despite its heavy use for medical purposes, no study has yet been conducted to assess its potentially toxic effects. This study aimed at evaluating the acute and subchronic toxicological profile of Tectona grandis leaf extract in rats. The acute toxicity study revealed neither behavioral disturbances nor death in rats. The lethal dose (DL50) of this extract is greater than 5000 mg/kg body weight. The subchronic toxicity study showed no significant change in weight gain in rats at test doses throughout the treatment period. However, there was a significant decrease in alanine transaminase activity and serum protein levels at all doses. Alkaline phosphatase activity decreased at doses of 30, 90, and 270 mg/kg and increased at the dose of 810 mg/kg body weight. Serum and urinary urea levels increased simultaneously at doses of 270 and 810 mg/kg body weight. Repeated administration of the extract also increased total cholesterol, high-density lipoprotein levels in both sexes were compared to respective controls, and the ratio of high- to low-density lipoprotein was found to be greater than 1 in all animals. However, at the dose of 810 mg/kg, necrosis was observed on the kidney sections and vascular congestion on the liver sections of animals. Aqueous extract of T. grandis did not lead to any adverse effects in rats after acute and subchronic treatment at 30 and 90 mg/kg doses. This extract can, therefore, be used for the formulation of typhoid fever phytomedicine at the therapeutic dose of 30 mg/kg, but before this, chronic and mutagenic toxicity evaluations must be carried out.

Problems and Countermeasures for the Data Mining of Medical Records of Traditional Chinese Medicine in the Era of Big Data

The medical records of Traditional Chinese Medicine (TCM) such as Huangdi’s Canon of Medicine and Treatise on Typhoid and Miscellaneous Diseases have always been the hot research objects in the field of TCM. Many papers on the summary and statistical analysis of TCM medical records have appeared one after another, which has played a huge role in promoting the development of TCM. However, with the progress of the times, the research of Traditional Chinese Medicine should keep pace with the new times. The authors in this paper introduced the research status and role of the data mining technology and mining methods, the problems and countermeasures of data mining technology in the research of Traditional Chinese Medicine medical records at this stage.

Purification of Fim-C-Salmonella typhi recombinant protein with Ni-NTA resin as raw material for typhoid disease detection kit

Typhoid fever caused by Salmonella typhi is an endemic disease in Asia, including Indonesia. Based on data from the World Health Organization (WHO), there are 81% per 100,000 people in Indonesia infected with typhoid. Based on this, development of typhoid detection kit that is simple, fast, specific and sensitive is still needed. One of the developments of detection kits currently available is the antigen and antibody interaction approach. This study aims to obtain comprehensive information about purification of recombinant Fim-C-S. typhi proteins as antigens for raw materials for manufacturing typhoid detection kits. This study uses the IMAC method with Ni2+ metal, which has advantages in high selectivity and purity. The results of this study report that purification of recombinant Fim-C-S. typhi protein inclusion bodies with variations in the binding and washing process at 3, 5, and 7 times gave percent yields correspondingly of 37.84, 39.44, and 38.21% pure protein. Previous studies have also reported variations in binding and washing at 2, 4, and 6 times and gave percent yields respectively were 35.37, 39.11, and 40.49%. Based on the data, we concluded that the variation of 6 times is the best repetition variation to get the largest percent yield so that it can be used as a reference in large-scale purification.

Anti-epidemic Measures of Municipal Authorities in Western Siberia in Late XIX — Early XX Centuries

The events in the late XIX — early XX centuries in Western Siberia, where the population survived several epidemics of cholera, typhus and typhoid fever, measles and other infectious diseases, are considered. It is noted that the sad result of the outbreak of many infections was the high epidemic mortality of the population. The activity of municipal authorities on the prevention and control of the spread of widespread diseases, the prevention of high mortality among the sick is being studied. The anti-epidemic measures taken by local authorities are analyzed: an increase in expenditures for urban improvement; the publication of mandatory sanitary regulations; creation of medical and sanitary executive commissions; division of the city territory into sections and assignment of sanitary guardians to them; arrangement of bacteriological laboratories, infectious barracks and disinfection chambers; health education of the population. The conclusion is made about positive changes in the prevention and treatment of a number of infectious diseases, the organization of sanitary supervision over the state of water supply sources, places of sale of food, the maintenance of garbage and cesspools, the dumping of sewage on strictly designated areas. At the same time, attention is drawn to the persistence of high epidemic mortality (especially infant mortality) due to the low standard of living of most of the townspeople, malnutrition, poor development of hygiene skills, lack of awareness of the causes and methods of treating diseases.

Pullorum Disease: Evolution of the Eradication Strategy.

The history of pullorum disease is closely intertwined with the history of avian health research and that of the poultry industry. The seriousness of the disease galvanized the attention and brought together, for the first time, the pioneers of poultry health research to work cooperatively on different aspects of the disease. Control of the disease made it possible for intensive poultry production to develop as the basis for the modern poultry industry. During the early 1900s, bacillary white diarrhea (BWD) was a devastating disease of young chickens threatening the developing poultry industry. Dr. Leo F. Rettger isolated and described the bacterial pathogen, Salmonella enterica serotype Pullorum, for the first time in 1900. BWD was renamed pullorum disease in 1929. In subsequent years, Rettger and coworkers were able to reproduce the disease and fulfill Koch's postulates. Rettger et al. also showed that Salmonella Pullorum was vertically transmitted, which was the first time that a pathogen was shown to be vertically transmitted. The development of serologic tests was of crucial importance because it led to the development of effective eradication methods to identify carrier birds and to exclude these birds from the breeder flocks. The negative impact of pullorum disease on the poultry industry ultimately was one of the major reasons that the National Poultry Improvement Plan (NPIP) was developed by scientists, the poultry industry, and the United States Department of Agriculture (USDA). Needless to say, the work of the pioneering researchers formed the basis for the control of the disease. The NPIP started in 1935, with 34 states participating in testing 4 million birds representing 58.2% of the birds hatched. The program rapidly expanded to 47 states by 1948 and tested more than 30 million birds. In 1967, all commercial chicken hatcheries participating in the NPIP were 100% free of pullorum and typhoid disease caused by Salmonella enterica serotype Gallinarum. This historical overview of pullorum disease describes in some detail the progress made, especially during the early years, toward controlling this disease using methodologies that were often very basic but nonetheless effective. One has to admire the ingenuity and persistence of the early researchers leading to their achievements considering the research tools that were available at the time.

Treatment strategy and thought on classical herbal formulae for coronavirus disease 2019

Coronavirus disease 2019(COVID-19) refers to the pneumonia caused by novel coronavirus(2019-nCoV) infection in 2019. It is highly infectious, with quick spreading and a wide range of impact. It has been broken out in many countries around the world and has become a public health emergency of international concern. Chinese medicine has a long history in treating plague, and viral disease is the clinical advantage in Chinese medicine. Under the premise that there is currently no specific drug treatment, Chinese medicine has achieved certain effects in the treatment of COVID-19, which has attracted much attention and has been upgraded to a national strategy. Regarding the treatment of COVID-19 with Chinese medicine, it is believed that in terms of the name of Chinese medicine, the modern connotation of &quot;uniform of typhoid and febrile disease&quot; should be re-recognized, and it is advisable to use drugs based on specific clinical prescriptions and indications. In terms of pathogenesis, the COVID-19 has the pathogenesis rules including from the mild to severe conditions, from the surface to the inside, from the excess syndrome to the deficiency syndrome. We should pay attention to the Taiyang syndrome damaged by wet disease in initial stage, Shaoyang syndrome complicated with Yangming syndrome in the middle stage, phlegm-heat obstructing lung in critical period, lung and spleen deficiency in the recovery stage. In terms of clinical treatment strategies, Dayuan Yin is recommended to induce sweat and disperse the stasis in early stage. Xiaochaihu Decoction and Maxing Shigan Decoction is used to relieve both exterior and interior symptoms in middle stage. In critical stage, Tingli Dazao Xiefei Decoction, Weijing Decoction, Xuanbai Chengqi Decoction, Xiaoxianxiong Decoction, and Sanzi Yangqin Decoction are considered to reduce phlegm and clear heat. We should pay attention to nourishing Qi and strengthening the spleen by Zhuye Shigao Decoction, Sha-shen Maidong Decoction, and Liujunzi Decoction in the later recovery period. It shall be noted that, no matter in the initial mild stage, the middle and critical stages, or in the later recovery stage, Chinese medicine plays an important role, including preventing mild to severe disease, shortening the fever time, improving cough symptoms, increasing blood oxygen saturation and reducing mortality. Many studies have shown that the classical herbal formulae can alleviate the cytokine storm, regulate the immune imbalance, and produce the potential effect of synergistic treatment for COVID-19 through multiple components, multiple targets, and multiple pathways.

A Framework Questionnaire for Diagnosing Infectious Disease Using Machine Learning Techniques

Infectious diseases weigh down the communities in the world and scientists to spend more effort via keeping tracking of evolving treatment and detecting methods. These diseases may lead to harm life of people. Early diagnosis could significantly support healthcare specialists to save more lives. Additionally, the pandemic leads to maximizing hospitals visits, medical clinics and healthcare centres. The international health organizations also have shown that there has been a rapid growth of infected cases. Therefore, correct diagnosis has become a pressing problem. Consequently, automated diagnosis becomes a sensible solution to the problem of these diagnosis challenges. This study was conducted to identify the most common infectious diseases in the Iraqi society using a well-designed questionnaire and a proposed automated diagnostic technique. Firstly, the top diseases questionnaire is distributed around the city of Baghdad to different medical clinics. The results from the preliminary analysis of the collected responses (115 responses) showed that the most common widespread diseases in the Iraqi community are diabetes, flu, and typhoid. This was followed by another questionnaire for the identification of symptoms and blood test variables for these diseases. It is worth pointing out that there are not sufficient and updated studies dealing with the diseases that attack the Iraqi community. Toward the automated diagnosis, both infectious diseases (flu and typhoid), identified symptoms are employed as feature space with one of the machine learning techniques. For the results evaluation different measures, such as accuracy, confusion matrix, and efficient verification via ROC, have been used to indicate the system performance. The result shows that typhoid disease has significant diagnosis accuracy of 98% compared to the others. While three machine learning systems named (Native Bayes, Linear discriminant, and Ensemble (subspace discriminant)) were used to diagnose flu disease. The resulting accuracy of all three models are 92% which shows good performing. Therefore, the proposed method shows precise accuracy and systematic manner for analyzing infectious diseases.

Infections Due to Salmonella

Salmonella, which is acquired via ingestion, is classified as nontyphoidal or typhoidal disease. Typhoidal disease is caused by S typhi or S paratyphi, and nontyphoidal disease is caused by all other serovars. Salmonella causes a range of infectious syndromes that include gastroenteritis, bacteremia, endovascular infections, and enteric fever. For immunocompromised hosts or patients with extraintestinal disease, antibiotic therapy should be provided. Effective agents often include third-generation cephalosporins and fluoroquinolones, although rates of resistance of Salmonella isolates to many antibiotics are increasing. A carrier state exists whereby patients may shed bacteria despite being asymptomatic. To eradicate the carrier state, longer courses of antibiotics and, in rare instances, surgical removal of the reservoir, which is most commonly the gallbladder, may be required. This review contains 2 figures, 4 tables, and 24 references. Key Words: Salmonella, typhoidal, non-typhoidal, enteric fever, endovascular infection, gastroenteritis, carrier, food-borne, antibiotic resistance

Spatio-temporal trends and distribution patterns of typhoid disease in Uganda from 2012 to 2017.

Typhoid disease continues to be a global public health burden. Uganda is one of the African countries characterized by high incidences of typhoid disease. Over 80% of the Ugandan districts are endemic for typhoid, largely attributable to lack of reliable knowledge to support disease surveillance. Spatial-temporal studies exploring major characteristics of the disease within the local population have remained limited in Uganda. The main goal of the study was to reveal spatial-temporal trends and distribution patterns of typhoid disease in Uganda for the period 2012 to 2017. Spatial-temporal statistics revealed monthly and annual trends of the disease at both regional and national levels. Results show that outbreaks occurred during 2015 and 2017 in central and eastern regions, respectively. Spatial scan statistic using the discrete Poisson model revealed spatial clusters of the disease for each of the years from 2012 to 2017, together with populations at risk. Most of the disease clustering was in the central region, followed by western and eastern regions (P <0.01). The northern region was the safest throughout the study period. This knowledge helps surveillance teams to i) plan and enforce preventive measures; ii) effectively prepare for outbreaks; iii) make targeted interventions for resource optimization; and iv) evaluate effectiveness of the intervention methods in the study period. This exploratory research forms a foundation of using Geographical Information Systems (GIS) in other related subsequent research studies to discover hidden spatial patterns that are difficult to discover with conventional methods.

Analysis and multiple control measures for a typhoid fever disease model

Typhoid fever is one of the diseases that is affecting humanity globally especially in the developing countries where access to clean environment and food are limited. We formulate a dynamical system model to study the effects of multiple control measures (i.e, vaccination, treatment and environmental sanitation) in mitigating typhoid fever disease. The qualitative analysis of our model was carried out accordingly. The impact of introducing the control measures were estimated using appropriate mathematical analysis and numerical simulations.

Water Infrastructure and Health in U.S. Cities

Between 1900 and 1930 typhoid fever and other waterborne diseases were largely eradicated from U.S. cities. This achievement required a mix of technological, scientific, economic, and bureaucratic innovations. This article examines how the interaction of those forces influenced water and sanitary infrastructure provision during the 19th and early 20th centuries. I show the sharp link between infrastructure investments and declines in waterborne disease and discuss how that relationship informs the methodological approaches one should use to assess the impact of sanitary investments on urban development. Finally, I review the literature on the social returns to eliminating the threat of waterborne disease. The evidence suggests the benefits of infrastructure investment far exceeded the costs. Institutional subscribers to the NBER working paper series, and residents of developing countries may download this paper without additional charge at www.nber.org.

Solution of typhoid fever model by Adomian decomposition method

In this paper, we presents a deterministic mathematical model on the dynamics of typhoid fever disease. The Adomian Decomposition Method (ADM) is used to solve the model equations. In solving the model, the validity of the ADM is established by the classical fourth-order Runge-Kutta method implemented in Maple 18. In other to confirm the accuracy of the method, a comparison was carried out between the ADM solution and Runge-Kutta(RK4). The findings obtained confirm the precision and accuracy of the ADM to cope with the study of morden epidemics.

On the deterministic and stochastic model applications to typhoid fever disease dynamics

A deterministic and stochastic model depicting typhoid fever spread in human host community is considered. The deterministic model is analyzed and found to be positively invariant, well – posed and meaningful in the sense of typhoid infection spread. Using the typhoid fever – absent equilibrium points, the control basic reproduction threshold (Rtyp ) of the model is obtained and the estimation yields Rtyp ≈ 0.744. This value implies that controls of vaccination, screening and treatment is effective enough to drive Rtyp below unity, that is, the level of infection is not effective to cause a typhoid epidemic. Also, the deterministic model is changed into a stochastic model system and the mean and variance of the stochastic model are obtained. The existence and uniqueness of the stochastic model is discussed and the corresponding graphical description of the impact of some parameters against is Rtyp plotted, while the stochastic simulations are done using the Euler - Maruyama numerical scheme coded in matlab to describe the behavior of each sub - population of human individuals of the model system.

Pengaruh Karakteristik Pasien 4 Diagnosis Penyakit Rawat Inap dengan Biaya Tertinggi di PT Asuransi ABC Terhadap Biaya Rawat Inap Berdasarkan Data Klaim

PT Asuransi ABC in collaboration with 68 companies, consists of 34960 participants, of which there are 1731 participants who filed claims. This study uses secondary data period July 1, 2013 - 30 September 2014. This study focused on inpatient claims, where there are 4 burdensome disease diagnosis PT Asuransi ABC at a high cost, those are coronary atrial diseases, chronic renal failure, typhoid fever, dengue haemorrhagic fever. Multiple correspondence analysis method is used to find the characteristics of each patient's disease diagnosis as well as the tendency of the characteristics of the patients in the cost of hospitalization . From the research, there are differences in patient characteristics between the disease and also the trend in the cost of hospitalization . Furthermore, the multiple linear regression analysis of patient characteristics influence on the cost of hospitalization . From the results of research only typhoid disease hospitalization costs are influenced by patient characteristics .

Narratives of Health and Well-Being: Disease and Bargaining in Cali, Colombia, 1930–1940

Over the course of the twentieth century, Cali, located in Colombia's southwest, became one of the nation's largest and most important urban centers. The city's rapid demographic expansion stemmed from multiple factors: the opening of the Panama Canal; the city's proximity and railway connection to Buenaventura, Colombia's major port on the Pacific; and the consolidation of a political and economic elite whose fortunes were tied to sugarcane production and the commercialization of coffee. As Cali's elites worried over how to modernize the city, the municipality's growth often outpaced its ability to guarantee and protect its residents' health. Tuberculosis, smallpox, syphilis, cholera, typhoid, dysentery, and other diarrheal diseases were common. The implementation of hygiene and sanitation measures in Cali reveals tensions and contradictions between, on one hand, elite imaginaries about the role hygiene and public health would play in defending the city's and nation's "human capital," and on the other, institutional practices that relied on careful bargaining between state officials and local communities. This article analyzes 1930s municipal council records to show how, for residents of Cali's working-class neighborhoods, claiming the right to health and protection relied on negotiations with local authorities through institutional means that allowed them to respond to, adapt, and at times contest official discourses and practices. Health and disease gave petitioners a language with which to construct individual and collective identities, talk about citizenship, and defend their rights.

GeoSentinel: past, present and future†.

Rationale for reviewIn response to increased concerns about emerging infectious diseases, GeoSentinel, the Global Surveillance Network of the International Society of Travel Medicine in partnership with the US Centers for Disease Control and Prevention (CDC), was established in 1995 in order to serve as a global provider-based emerging infections sentinel network, conduct surveillance for travel-related infections and communicate and assist global public health responses. This review summarizes the history, past achievements and future directions of the GeoSentinel Network.Key findingsFunded by the US CDC in 1996, GeoSentinel has grown from a group of eight US-based travel and tropical medicine centers to a global network, which currently consists of 68 sites in 28 countries. GeoSentinel has provided important contributions that have enhanced the ability to use destination-specific differences to guide diagnosis and treatment of returning travelers, migrants and refugees. During the last two decades, GeoSentinel has identified a number of sentinel infectious disease events including previously unrecognized outbreaks and occurrence of diseases in locations thought not to harbor certain infectious agents. GeoSentinel has also provided useful insight into illnesses affecting different traveling populations such as migrants, business travelers and students, while characterizing in greater detail the epidemiology of infectious diseases such as typhoid fever, leishmaniasis and Zika virus disease.ConclusionsSurveillance of travel- and migration-related infectious diseases has been the main focus of GeoSentinel for the last 25 years. However, GeoSentinel is now evolving into a network that will conduct both research and surveillance. The large number of participating sites and excellent geographic coverage for identification of both common and illnesses in individuals who have traversed international borders uniquely position GeoSentinel to make important contributions of travel-related infectious diseases in the years to come.

Homologous and heterologous re-challenge with Salmonella Typhi and Salmonella Paratyphi A in a randomised controlled human infection model.

Enteric fever is a systemic infection caused by Salmonella Typhi or Paratyphi A. In many endemic areas, these serovars co-circulate and can cause multiple infection-episodes in childhood. Prior exposure is thought to confer partial, but incomplete, protection against subsequent attacks of enteric fever. Empirical data to support this hypothesis are limited, and there are few studies describing the occurrence of heterologous-protection between these closely related serovars. We performed a challenge-re-challenge study using a controlled human infection model (CHIM) to investigate the extent of infection-derived immunity to Salmonella Typhi or Paratyphi A infection. We recruited healthy volunteers into two groups: naïve volunteers with no prior exposure to Salmonella Typhi/Paratyphi A and volunteers previously-exposed to Salmonella Typhi or Paratyphi A in earlier CHIM studies. Within each group, participants were randomised 1:1 to oral challenge with either Salmonella Typhi (104 CFU) or Paratyphi A (103 CFU). The primary objective was to compare the attack rate between naïve and previously challenged individuals, defined as the proportion of participants per group meeting the diagnostic criteria of temperature of ≥38°C persisting for ≥12 hours and/or S. Typhi/Paratyphi bacteraemia up to day 14 post challenge. The attack-rate in participants who underwent homologous re-challenge with Salmonella Typhi was reduced compared with challenged naïve controls, although this reduction was not statistically significant (12/27[44%] vs. 12/19[63%]; Relative risk 0.70; 95% CI 0.41–1.21; p = 0.24). Homologous re-challenge with Salmonella Paratyphi A also resulted in a lower attack-rate than was seen in challenged naïve controls (3/12[25%] vs. 10/18[56%]; RR0.45; 95% CI 0.16–1.30; p = 0.14). Evidence of protection was supported by a post hoc analysis in which previous exposure was associated with an approximately 36% and 57% reduced risk of typhoid or paratyphoid disease respectively on re-challenge. Individuals who did not develop enteric fever on primary exposure were significantly more likely to be protected on re-challenge, compared with individuals who developed disease on primary exposure. Heterologous re-challenge with Salmonella Typhi or Salmonella Paratyphi A was not associated with a reduced attack rate following challenge. Within the context of the model, prior exposure was not associated with reduced disease severity, altered microbiological profile or boosting of humoral immune responses. We conclude that prior Salmonella Typhi and Paratyphi A exposure may confer partial but incomplete protection against subsequent infection, but with a comparable clinical and microbiological phenotype. There is no demonstrable cross-protection between these serovars, consistent with the co-circulation of Salmonella Typhi and Paratyphi A. Collectively, these data are consistent with surveillance and modelling studies that indicate multiple infections can occur in high transmission settings, supporting the need for vaccines to reduce the burden of disease in childhood and achieve disease control.Trial registration NCT02192008; clinicaltrials.gov.