Risk factors for typhoid fever among adult patients in Diyarbakir, Turkey

We conducted a case-control study to assess risk factors for typhoid fever in Diyarbakir, Turkey, a region where transmission of Salmonella typhi is endemic. We prospectively identified febrile patients from Diyarbakir and the surrounding area who were admitted to hospital. Cases were defined as patients who had S. typhi isolated from at least one blood culture. Sixty-four cases with blood culture-confirmed S. typhi were identified between May 2001 and May 2003. In total, 128 age- and sex-matched controls selected from neighbourhoods as cases were enrolled. We hypothesized that consumption of raw vegetables contaminated with sewage would be associated with an increased risk of typhoid fever. Conditional logistic regression modelling revealed that living in a crowded household (OR 3.31, 95% CI 1.58-6.92, P=0.002), eating cig kofte (a traditional raw food) (OR 5.29, 95% CI 2.20-12.69, P=0.000) and lettuce salad (OR 3.55, 95% CI 1.52-8.28, P=0.003) in the 15 days prior to symptoms onset was independently associated with typhoid fever. We conclude that living in a crowded household and consumption of raw vegetables outside the home increase the risk of typhoid fever in this region.     

Case-control study to identify risk factors for paediatric endemic typhoid fever in Santiago, Chile

Typhoid fever is an important endemic health problem in Santiago, Chile. Its incidence has more than doubled in recent years, during which access to potable water and sewage disposal in the home became almost universal in the city. A matched case—control study was carried out to identify risk factors and vehicles of transmission of paediatric typhoid fever; 81 children in the 3-14-years age group with typhoid fever were compared with controls, matched with respect to age, sex, and neighbourhood. It was found that case children more frequently bought lunch at school and shared food with classmates. Also, case children more often consumed flavoured ices bought outside the home; none of 41 other food items considered in the study was associated with a higher risk of typhoid fever. Only two food handlers for cases and one for controls were positive for Salmonella typhi, indicating that persons preparing food solely for their own family were not the main source of S. typhi infection. Rather, the risk factors identified in this study are consistent with the hypothesis that paediatric endemic typhoid fever in Santiago is largely spread by consumption of food-stuffs that are prepared outside the individual''s home and are shared with or sold to children.     

Risk factors associated with typhoid fever in Son La province, northern Vietnam

Between July and December 2002, we undertook a hospital-based case-control study to identify risk factors associated with typhoid fever in Son La province, northern Vietnam. Among 617 suspected cases, 90 cases of typhoid fever were confirmed by blood or stool culture. One hundred and eighty controls (neighbours of typhoid cases matched for gender and age) were chosen. Participants were interviewed at home using a standardized questionnaire. Seventy-five per cent of cases were aged 10-44 years. No cases in patients aged less than 5 years were recorded in this study. In a conditional logistic regression analysis recent contact with a typhoid patient (OR = 3.3, 95% CI 1.7-6.2, P < 0.001), no education (OR = 2.0, 95% CI 1.0-3.7, P = 0.03) and drinking untreated water (OR = 3.9, 95% CI 2.0-7.5, P < 0.001) were independently associated with typhoid fever. Improving quality of drinking water must be a priority and health education strategies targeted at individuals with no schooling, and contacts of patients, would be expected to decrease the burden of typhoid fever.     

Risk factors for typhoid fever in the Mekong delta, southern Viet Nam: a case-control study

In order to identify risk factors for typhoid fever in a highly endemic area, we undertook a case-control study in the Mekong delta, Viet Nam. Cases were 144 consecutive patients admitted to hospital with blood culture-confirmed typhoid fever. Two controls (1 in the hospital and 1 in the community) were chosen for each case. Standardized interviews were conducted with questions regarding recent contact with a typhoid fever patient, eating habits, hygiene and socio-economic level. Cases were more likely to have been in contact with a patient with typhoid fever than hospital controls (adjusted odds ratio (OR) = 5.2, 95% confidence interval (95% CI) 1.7-15.9) or community controls (adjusted OR = 11.9, 95% CI 2.3-60.7); 11% and 14% of typhoid fever cases (compared to hospital or community controls, respectively) were attributable to recent contact with a patient with this disease. These findings suggest that strategies directed towards the persons in contact with a patient might reduce the incidence of secondary cases of typhoid fever.     

宁波市1988--2007年伤寒副伤寒流行病学和病原学研究

目的 探讨伤寒副伤寒高发地区的流行病学和病原学特征.方法 运用描述流行病学与分析流行病学对1988-2007年伤寒副伤寒疫情资料和暴发资料进行分析.采集市场贝壳类海产品进行污染情况检测,并对患者中分离到的菌株进行实验室系统研究.结果 1988-2007年全市累计报告伤寒副伤寒病例19 404例,死亡7例,年平均发病率为17.68/10万,病死率为0.36‰.发病呈现周期性波动,冬春季高发,且存在明显地区聚集性,发病以20～50岁年龄的青壮年为主.流行菌株以甲型剐伤寒沙门菌为主.传播因素调查分析显示,居民生吃毛蚶和牡蛎是造成伤寒副伤寒高发的主要危险因素;同时从市场所采集的毛蚶和牡蛎中,各检出1株甲型副伤寒沙门菌,并带有TEM-1型耐药基因.甲型副伤寒沙门菌在海产品牡蛎中存活观察试验证实菌株在带壳牡蛎活体水体中至少能存活10 d以上.PFGE基因分型表明,X2型是宁波地区甲型副伤寒优势流行株.结论 宁波地区居民生吃毛蚶和牡蛎是造成伤寒副伤寒高发的丰要危险因素,加强对贝壳类海产品的卫生监督管理和对居民的健康教育是预防控制伤寒副伤寒的关键措施.     

Risk factors for typhoid fever in an endemic setting,Karachi, Pakistan.

We conducted a study to evaluate risk factors for developing typhoid fever in a setting where the disease is endemic in Karachi, Pakistan. We enrolled 100 cases with blood culture-confirmed Salmonella typhi between July and October 1994 and 200 age-matched neighbourhood controls. Cases had a median age of 5.8 years. In a conditional logistic regression model, eating ice cream (Odds ratio [OR] = 2.3; 95% confidence interval [CI] 1.2-4.2, attributable risk [AR] = 36%), eating food from a roadside cabin during the summer months (OR = 4.6, 95% CI 1.6-13.0; AR = 18%), taking antimicrobials in the 2 weeks preceding the onset of symptoms (OR = 5.7, 95% CI 2.3-13.9, AR = 21%), and drinking water at the work-site (OR = 44.0, 95% CI 2.8-680, AR = 8%) were all independently associated with typhoid fever. There was no difference in the microbiological water quality of home drinking water between cases and controls. Typhoid fever in Karachi resulted from high-dose exposures from multiple sources with individual susceptibility increased by young age and prior antimicrobial use. Improving commercial food hygiene and decreasing unnecessary antimicrobial use would be expected to decrease the burden of typhoid fever.     

Helicobacter pylori infection and typhoid fever in Jakarta, Indonesia

We evaluated the association between typhoid fever and Helicobacter pylori infection, as the latter microorganism may influence gastric acid secretion and consequently increase susceptibility to Salmonella typhi infection. Anti-H. pylori IgG and IgA antibody titres (ELISA) and gastrin concentration (RIA) were determined in the plasma of 87 blood culture-confirmed typhoid fever cases (collected after clinical recovery) and 232 random healthy controls without a history of typhoid fever, in the Jatinegara district, Jakarta. Patients with typhoid fever more often than controls were seropositive for H. pylori IgG (67% vs. 50%, P<0.008), when antibody titres were dichotomized around median titres observed in controls. H. pylori IgA seropositivity was not associated with typhoid fever. Plasma gastrin concentrations indicative of hypochlorhydria (i.e. gastrin > or =25 or > or =100 ng/l) were not significantly elevated in typhoid fever cases compared to controls (P=0.54 and P=0.27 respectively). In a multivariate analysis, typhoid fever was independently associated with young age (<33 years, median age of the controls) [odds ratio (OR) 7.93, 95% confidence interval (CI) 3.90-16.10], and H. pylori IgG seropositivity (OR 1.93, 95% CI 1.10-3.40). Typhoid fever was independently associated with H. pylori IgG seropositivity, but not with elevated gastrin concentration. Therefore, the association suggests a common risk of environmental exposure to both bacteria, e.g. poor hygiene, rather than a causal relationship via reduced gastric acid production.     

Risk factors for typhoid fever in a slum in Dhaka, Bangladesh

We systematically investigated risk factors for typhoid fever in Kamalapur, a poor urban area of Bangladesh, to inform targeted public health measures for its control. We interviewed patients with typhoid fever and two age-matched controls per case about exposures during the 14 days before the onset of illness. The municipal water supply was used by all 41 cases and 81of 82 controls. In multivariate analysis, drinking unboiled water at home was a significant risk factor [adjusted odds ratio (aOR) 12.1, 95% CI 2.2-65.6]. Twenty-three (56%) cases and 21 (26%) controls reported that water from the primary source was foul-smelling (aOR 7.4, 95% CI 2.1-25.4). Eating papaya was associated with illness (aOR 5.2, 95% CI 1.2-22.2). Using a latrine for defecation was significantly protective (aOR 0.1, 95% CI 0.02-0.9). Improved chlorination of the municipal water supply or disinfecting drinking water at the household level may dramatically reduce the risk of typhoid fever in Kamalapur. The protective effect of using latrines, particularly among young children, should be investigated further.     

Effectiveness of typhoid conjugate vaccine against culture-confirmed typhoid in a peri-urban setting in Karachi: A case-control study

BackgroundEnteric fever, caused by Salmonella Typhi and S. Paratyphi, is a cause of high morbidity and mortality among children in South Asia. Rising antimicrobial resistance presents an additional challenge. Typhoid Conjugate Vaccines (TCV) are recommended by the World Health Organization for use among people 6 months to 45 years old living in endemic settings. This study aimed to assess the effectiveness of TCV against culture-confirmed S. Typhi in Lyari Town, Karachi, Pakistan. This peri-urban town was one of the worst affected by the outbreak of extensively drug resistant (XDR) typhoid that started in November 2016.MethodsA matched case-control study was conducted following a mass immunization campaign with TCV at three key hospitals in Lyari Town Karachi, Pakistan. Children aged 6 months to 15 years presenting with culture-confirmed S. Typhi were enrolled as cases. For each case, at least 1 age-matched hospital control and two age-matched community controls were enrolled. Adjusted odds ratios with 95% confidence intervals (CIs) were calculated using conditional logistic regression.ResultsOf 82 typhoid fever patients enrolled from August 2019 through December 2019, 8 (9·8%) had received vaccine for typhoid. Of the 164 community controls and 82 hospital controls enrolled, 38 (23·2%) community controls and 27 (32·9%) hospital controls were vaccinated for typhoid. The age and sex-adjusted vaccine effectiveness was found to be 72% (95% CI: 34% − 88%). The consumption of meals prepared outside home more than once per month (adjusted odds ratio: 3·72, 95% CI: 1·55- 8·94; p-value: 0·003) was associated with the development of culture-confirmed typhoid.ConclusionA single dose of TCV is effective against culture confirmed typhoid among children aged 6 months to 15 years old in an XDR typhoid outbreak setting of a peri-urban community in Karachi, Pakistan.     

2004～2010年福建省伤寒、副伤寒流行特征分析

[目的]了解福建省伤寒、副伤寒(伤寒)发病规律,掌握流行趋势,为制订伤寒的防治对策提供科学依据。[方法]对2004～2010年福建省伤寒疫情资料进行分析。[结果]2004～2010年福建省累计报告伤寒3 341例,年均发病率为1.33/10万。伤寒发病率(/10万),2004～2010年分别为1.80、1.42、1.51、1.08、1.23、1.18、1.13(P<0.01)。2004～2010年年均发病率(/10万),最高的是宁德市(2.88)、龙岩市(2.80)、厦门市(2.77);男性为1.44,女性为1.22(P<0.01);0～4岁为2.86,5～14岁为1.25,15～34岁为1.31,35～54岁为1.17,55～74岁为1.13,≥75岁为1.19。2004～2010年的3 341例伤寒病人中,5～10月发病的占61.33%;农民占22.96%,学生占15.41%,散居儿童占10.98%。2006年厦门市城区内发生伤寒流行,1月1日至7月31日报告病例190例,分离菌株中主要为甲型副伤寒沙门菌,流行原因为养殖地贝类被污染。其他病例均为散发。2006～2010年累计从伤寒病人分离出伤寒病原菌102株,其中伤寒沙门菌占30.39%,甲型副伤寒沙门菌占53.92%,乙型副伤寒沙门菌占13.73%,丙型副伤寒沙门菌占1.96%。[结论]2004～2010年福建省伤寒发病率维持在较低水平,5岁以下儿童和青壮年为发病的重点人群。     

The malaria and typhoid fever burden in the slums of Kolkata, India: data from a prospective community-based study

Recent research has indicated that the malaria burden in Asia may have been vastly underestimated. We conducted a prospective community-based study in an impoverished urban site in Kolkata, India, to estimate the burden of malaria and typhoid fever and to identify risk factors for these diseases. In a population of 60452 people, 3605 fever episodes were detected over a 12-month period. The blood films of 93 febrile patients contained Plasmodium (90 P. vivax, 2 P. falciparum and 1 P. malariae). Blood cultures from 95 patients grew Salmonella enterica serotype Typhi. Malaria patients were found to be significantly older (mean age 29 years) compared with patients with typhoid fever (15 years; P<0.001) but had similar clinical features on presentation. Having a household member with malaria, illiteracy, low household income and living in a structure not built of bricks were associated with an increased risk for malaria. Having a household member with typhoid fever and poor hygiene were associated with typhoid fever. A geographic analysis of the spatial distribution of malaria and typhoid fever cases detected high-risk neighbourhoods for each disease. Focal interventions to minimise human-vector contact and improved personal hygiene and targeted vaccination campaigns could help to prevent malaria and typhoid fever in this site.     

Investigation of concurrent outbreaks of gastroenteritis and typhoid fever following a party on a floating restaurant, France, March 1998

A retrospective cohort study was carried out to investigate concurrent outbreaks of gastroenteritis and typhoid fever that occurred among guests of a supper on a floating restaurant in France in March 1998. A total of 133 guests (attack rate = 90%) reported gastroenteritis within 12 days of the supper. Twenty-seven guests developed typhoid fever (attack rate = 18%) of whom 15 were confirmed by stool or blood culture. All patients with typhoid fever had had an initial gastroenteritis. The results suggest that the same food items served during the supper, chicken and rice, were the vehicles of both gastroenteritis and typhoid fever, but the authors could not determine the specific source of infection. Initial gastroenteritis has been described as a clinical manifestation of typhoid fever but whether or not these two syndromes (gastroenteritis and typhoid fever) were due to the same etiology remains unclear in this outbreak.     

Risk factors associated with typhoid fever in children aged 2-16 years in Karachi, Pakistan

We analysed the data from the control group in a typhoid vaccine trial in Karachi to assess the differences in individual-, household- and cluster-level characteristics for developing typhoid fever. The annual incidence of typhoid in children aged 2-16 years in the control arm of the vaccine trial was 151/100 000 population. After adjustment, the risk of typhoid was lower with increasing age [risk ratio (RR) 0·89, 95% confidence interval (CI) 0·83-0·95], was higher with an increase in population density (RR 1·13, 95% CI 1·05-1·21) and was lower in the households using a safe drinking-water source (RR 0·63, 95% CI 0·41-0·99). Typhoid fever affects younger children living in areas of high population density and lack of access to safe water in Pakistan. A combination of environmental and biological interventions is required to prevent the continued epidemiological and economic impact of typhoid fever in high-risk areas of Pakistan.     

宁波市北仑区1985-2005年伤寒流行特征分析

目的探讨北仑区伤寒副伤寒流行特征,为今后防制工作提供科学依据。方法采用描述性流行病学方法,对1985-2005年北仑区法定传染病报告伤寒疫情资料进行系统分析。结果21年间北仑区伤寒年平均发病率为35.63/10万,每隔2-3年出现一个高流行年,1999年后伤寒疫情呈上升趋势。发病季节分布呈现春季单峰。发病以20-49岁年龄组为主(72.54%),本地户籍发病远大于外来流动人口。病原菌以甲型副伤寒沙门菌为主,危险因素分析提示伤寒流行与生吃、半生吃毛蚶、牡蛎等贝壳类海产品有关。结论北仑区属于伤寒高流行地区,流行因素主要与本地居民饮食习惯有关。加强饮食行为干预、加大贝壳类海产品监测,是控制当前北仑区伤寒高发的主要措施。     

A simple validated prediction rule to diagnose typhoid fever in Turkey

The goal of this study was to develop a simple prediction rule for the diagnosis of typhoid fever. A model for the prediction of patients with typhoid fever at hospital admission was derived and validated by assigning weighted point values to independent predictive factors associated with a diagnosis of typhoid fever at hospital admission. Patient demographic, clinical and laboratory variables were used to compare patients with blood culture-confirmed typhoid fever with patients with fever of unknown origin. The model was derived and validated in two separate cohorts of patients from Dicle University Hospital in Diyarbakir, Turkey. A total of 371 patients were enrolled. A diagnostic index score was created using seven independent predictive factors associated with typhoid fever at hospital admission: age <30 years, abdominal distention, confusion, leukopenia, relative bradycardia, positive Widal test and a typhoid tongue. A clinical prediction rule helped to differentiate patients with typhoid fever.     

Risk factors for enteric perforation in patients with typhoid Fever

A case-control study was performed using the records of patients hospitalized for typhoid fever at Dicle University Hospital, Diyarbakir, Turkey, between 1994 and 1998. Case patients with enteric perforation were compared with control patients with typhoid fever but no enteric perforation. Risk factors for perforation were determined using logistic regression modeling. Forty case patients who had surgery because of typhoid enteric perforation were compared with 80 control patients. In univariate analyses, male sex (p = 0.01), age (p = 0.01), leukopenia (p = 0.01), inadequate antimicrobial therapy prior to admission (p = 0.01), and short duration of symptoms (p = 0.01) were significantly associated with perforation. In multivariate analysis, male sex (odds ratio (OR) = 4.39, 95% confidence interval (CI): 1.37, 14.09; p = 0.01), leukopenia (OR = 3.88, 95% CI: 1.46, 10.33; p = 0.04), inadequate treatment prior to admission (OR = 4.58, 95% CI: 1.14, 18.35; p = 0.03), and short duration of symptoms (OR = 1.22, 95% CI: 1.10, 1.35; p = 0.001) were significant predictors of perforation. A short duration of symptoms, inadequate antimicrobial therapy, male sex, and leukopenia are independent risk factors for enteric perforation in patients with typhoid fever.     

Impact of Vi vaccination on spatial patterns of typhoid fever in the slums of Kolkata, India

A mass typhoid Vi vaccination campaign was carried out among approximately 60,000 slum residents of Kolkata, India. This study evaluated the impact of the campaign on spatial patterns of typhoid fever. Eighty contiguous residential groups of households in the study area were randomized to receive either a single dose of the Vi polysaccharide vaccine or a single dose of the inactivated hepatitis A vaccine as the control agent. Persons aged two years and older were eligible to receive the vaccine. Vaccine protection against typhoid fever was monitored for two years after vaccination at both outpatient and inpatient facilities serving the study population. Geographic analytic and mapping tools were used in the analysis. Spatial randomness of the disease was observed during the pre-vaccination period, which turned into a significant pattern after vaccination. The high-risk areas for typhoid were observed in the area dominated by the control clusters, and the low-risk areas were in the area dominated by the Vi clusters. Furthermore, the control clusters surrounded by the Vi clusters were low risk for typhoid fever. The results demonstrated the ability of mass vaccination to change the spatial patterns of disease through the creation of spatial barriers to transmission of the disease. Understanding and mapping the disease risk could be useful for designing a community-based vaccination strategy to control disease.     

临沂市2001～2005年伤寒、副伤寒资料分析

[目的]探讨临沂市伤寒、副伤寒流行特征,制定有效的控制措施.[方法]对临沂市2001～2005年伤寒疫情报告及流行病学调查资料进行分析.[结果]2001～2005年临沂市共报告伤寒、副伤寒病人2330例,无死亡病例,年平均发病率为4.61/10万.发病具有明显的季节性;年龄主要集中在15～40岁年龄段,占70.86%(1651/2330);农民和中、小学生是主要的发病人群,分别占33.05%(770/2330)、17.85%(416/2 330);平原伤寒、副伤寒发病率高于山区;临床特征不典型;近3年我市以甲型副伤寒发病为主.[结论]应采取以切断经水传播、免疫接种和敏感药物治疗为主的综合性防治措施以控制临沂市的伤寒、副伤寒疫情.     

Comparisons of predictors for typhoid and paratyphoid fever in Kolkata,India

Background:

Exposure of the individual to contaminated food or water correlates closely with the risk for enteric fever. Since public health interventions such as water improvement or vaccination campaigns are implemented for groups of individuals we were interested whether risk factors not only for the individual but for households, neighbourhoods and larger areas can be recognised?

Methods:

We conducted a large enteric fever surveillance study and analyzed factors which correlate with enteric fever on an individual level and factors associated with high and low risk areas with enteric fever incidence. Individual level data were linked to a population based geographic information systems. Individual and household level variables were fitted in Generalized Estimating Equations (GEE) with the logit link function to take into account the likelihood that household factors correlated within household members.

Results:

Over a 12-month period 80 typhoid fever cases and 47 paratyphoid fever cases were detected among 56,946 residents in two bustees (slums) of Kolkata, India. The incidence of paratyphoid fever was lower (0.8/1000/year), and the mean age of paratyphoid patients was older (17.1 years) than for typhoid fever (incidence 1.4/1000/year, mean age 14.7 years). Residents in areas with a high risk for typhoid fever had lower literacy rates and economic status, bigger household size, and resided closer to waterbodies and study treatment centers than residents in low risk areas.

Conclusion:

There was a close correlation between the characteristics detected based on individual cases and characteristics associated with high incidence areas. Because the comparison of risk factors of populations living in high versus low risk areas is statistically very powerful this methodology holds promise to detect risk factors associated with diseases using geographic information systems.

     

台州地区伤寒副伤寒的流行状况及防控对策

目的 了解和掌握台州地区伤寒副伤寒流行病学和病原分子生物学特征,分析其流行因素,探讨防控对策.方法 对全市伤寒副伤寒疫情资料进行描述流行病学分析,结合实验研究对采取的防控措施进行科学评价.结果 台州市伤寒副伤寒疫情从2001年开始逐年抬升,发病率从2001年的22.83/10万上升到2004年的61.55/10万,2007年降到9.02/10万;优势病原菌由伤寒杆菌转变为甲型副伤寒杆菌,后者又以X2基因为主.发病季节提前,发病点多面广相对集中,临床表现极不典型,各年龄组均有发病,10～59岁之间的占报告病例总数的90.34%,男女发病之比为1.31∶1,以民工、农民、学生为主;饮用水污染和生食或半生食贝类食品为发病的主要危险因素.结论 针对流行病学和病原学病因采取综合性防控措施,推进饮用水安全卫生与改厕无害化建设、落实健康教育与健康促进等是控制伤寒副伤寒流行的根本性措施.