Cases of typhoid fever imported into England, Scotland and Wales (2000–2003)

Contribution of the gyrA and waaG mutants to fluoroquinolones resistance, biofilm development, and persister cells formation in Salmonella enterica serovar Typhi

Fluoroquinolone resistance in Salmonella has been reported worldwide and poses a serious public health threat in developing countries. Multiple factors contribute to fluoroquinolone resistance, including mutations in DNA gyrase and the acquisition of antimicrobial resistance genes. Salmonella enterica serovar Typhi (S. Typhi) causes typhoid fever in humans, which is highly prevalent in counties with poor sanitation and hygiene standards. Here, we reported S. Typhi clinical isolates that showed varying degrees of susceptibility to fluoroquinolones and were characterized by Analytical Profile Index 20E test kit and 16S rRNA sequencing. S. Typhi strain S27 was resistant to fluoroquinolones and had multiple mutations in the gyrA gene. The gyrA lies in the quinolone resistance determining region of S. Typhi and has mutations at codon 83 (Ser83Phe), codon 87 (Asp87Gly), codon 308 (Lys308Glu), and codon 328 (Val328Ile). S. Typhi strain S6 has no gyrA mutations and is sensitive to fluoroquinolones but forms a strong biofilm relative to S. Typhi S27. Transcriptional analysis of biofilm associated genes revealed that the waaG gene was significantly downregulated. The ΔwaaG mutant showed a significant decrease in persister cells and a strong biofilm formation relative to wild type and gyrA mutant. The gyrA tetra mutant persister assay revealed a significant increase in persister cells compared to wild type and ΔwaaG. Collectively, this is the first report of S. Typhi's two key genes and their roles in antibiotic tolerance, biofilm formation, and fluoroquinolone resistance that can help in understanding the mechanism of persister formation and eradication.

Infectious Mimics of Inflammatory Bowel Disease

Distinguishing inflammatory bowel disease (IBD) from its mimics remains a diagnostic challenge for surgical pathologists. Several gastrointestinal infections produce inflammatory patterns that overlap with typical findings of IBD. Although stool culture, PCR, and other clinical assays may identify infectious enterocolitides, these tests may not be performed or the results may be unavailable at the time of histologic evaluation. Furthermore, some clinical tests, including stool PCR, may reflect past exposure rather than ongoing infection. It is important for surgical pathologists to be knowledgeable about infections that simulate IBD in order to generate an accurate differential diagnosis, perform appropriate ancillary studies, and prompt clinical follow-up. This review covers bacterial, fungal, and protozoal infections in the differential diagnosis of IBD.

British Infection Association Guidelines for the Diagnosis and Management of Enteric Fever in England

Enteric fever (EF) is an infection caused by the bacteria called Salmonella Typhi or Paratyphi. Infection is acquired through swallowing contaminated food or water. Most EF in England occurs in people returning from South Asia and other places where EF is common; catching EF in England is rare. The main symptom is fever, but stomach pain, diarrhoea, muscle aches, rash and other symptoms may occur. EF is diagnosed by culturing the bacteria from blood and/or stool in a microbiology laboratory. EF usually responds well to antibiotic treatment. Depending on how unwell the individual is, antibiotics may be administered by mouth or by injection. Over the past several years, there has been an overall increase in resistance to antibiotics used to treat enteric fever, in all endemic areas. Additionally, since 2016, there has been an ongoing outbreak of drug-resistant EF in Pakistan. This infection is called extensively drug-resistant, or XDR, EF and only responds to a limited number of antibiotics. Occasionally individuals develop complications of EF including confusion, bleeding, a hole in the gut or an infection of the bones or elsewhere. Some people may continue to carry the bacteria in their stool for a longtime following treatment for the initial illness. These people may need treatment with a longer course of antibiotics to eradicate infection. Travellers can reduce their risk of acquiring EF by following safe food and water practices and by receiving the vaccine at least a few weeks before travel. These guidelines aim to help doctors do the correct tests and treat patients for enteric fever in England but may also be useful to doctors and public health professionals in other similar countries.

Validation of Pefloxacin for detection of fluoroquinolone (FQ) resistance among Salmonella Typhi with special reference to GyrB mutations

Introduction. Fluoroquinolone (FQ) resistant Salmonella are classified as high priority pathogens by WHO. FQ resistance among Salmonella Typhi has emerged rapidly and is predominantly mediated by mutations in the topoisomerase genes gyrA, and parC. Mutations in GyrA result in classical FQ resistance (DCS-NAR) i.e. decreased susceptibility to ciprofloxacin (MIC of 0.12 to 0.5 µg ml^-1) (DCS) and resistance to nalidixic acid (NAR). Previously a nalidixic acid disc test was proposed for detection of DCS. Recently isolates with non-classical FQ resistance caused by plasmid-mediated quinolone resistance (PMQR) and mutations in GyrB have emerged. These mechanisms also result in DCS but are nalidixic acid susceptible (NAS) and thus pose diagnostic challenges. CLSI and EUCAST have recommended use of 5 µg pefloxacin discs for detection of DCS in Salmonella.Hypothesis. The CLSI and EUCAST recommendations for use of 5 µg pefloxacin for detection of DCS has not been validated on typhoidal Salmonella and resistance mediated by GyrB mutation in Salmonella species.Aim. The aim of the present study was to validate the performance of the 5 µg pefloxacin discs to detect isolates of S. Typhi with DCS with special reference to GyrB mutations.Methodology. A total of 180 clinical isolates of Salmonella Typhi (2005-2014) were investigated for genetic mechanisms of resistance. Zone diameters for nalidixic acid (30μg), ciprofloxacin (5μg) and pefloxacin (5µg) and minimum inhibitory concentration (MIC) for ciprofloxacin were determined using CLSI guidelines. Performance of the three discs was evaluated to detect FQ resistance in S. Typhi.Results. Topoisomerase mutations in GyrB +/ ParC and GyrB were detected in 112 and 34 isolates respectively. Different mutations have a varied effect on the MIC for ciprofloxacin. The current breakpoints for susceptible (≤0.06 µg ml^-1) and non-susceptible (≥0.125 µg ml^-1), failed to detect all isolates with a resistance mechanism. Performance of both ciprofloxacin and pefloxacin discs were excellent compared to nalidixic acid in differentiating isolates with non-classical resistance mediated by GyrB from wild-type.Conclusion. The pefloxacin disc can be used to detect FQ resistance among S. Typhi. This is the first report of validation of pefloxacin for detection of FQ resistance in S. Typhi mediated by GyrB mutation.

Progress on the national action plan of Pakistan on antimicrobial resistance (AMR): a narrative review and the implications

Introduction: The emergence of antimicrobial resistance (AMR) is a threat to public health. In 2015, the World Health Organization (WHO) introduced a global action plan to tackle AMR in the World Health Assembly. Pakistan's national action plan (NAP) for AMR was released in May 2017 by the Ministry of National Health Services. Based on the NAP, strategies have been initiated on a national and provincial scale in Pakistan.Areas covered: This narrative review of the five components of the Pakistan NAP has been undertaken to discuss some of the challenges in implementation of the NAP for AMR in Pakistan including different opinions and views of key stakeholders, combined with suggestions on potential ways to reduce the burden of the AMR.Expert opinion: Going forward, healthcare authorities should focus on screening and monitoring of all the objectives of the NAP by establishing proper policies as well as promoting antimicrobial stewardship interventions and Infection prevention and control (IPC) practices. Overall, the comprehensive strengthening of the healthcare system is required to adequately implement the NAP, tackle continued inappropriate antimicrobial use and high AMR rates in Pakistan.

Fever in the Returned Traveler

International travel is associated with a risk of infections not typically seen in high-income settings. Malaria is the most important tropical infection in travelers, but epidemics of dengue, chikungunya, and Zika emphasize that clinicians need to be aware of the rapidly changing distribution of many arboviruses. A detailed travel history and a syndromic approach to the investigation and management of patients is key. Consultation with a specialist is often recommended to ensure that appropriate management and investigations are undertaken in febrile returned travelers.

•

Travel, especially to low-income regions, is associated with an increased risk of infections not typically seen in high-income countries (e.g., malaria, enteric fever, dengue, chikungunya, Zika, and schistosomiasis).

•

Although gastroenteritis, respiratory tract infections, and self-limiting viral infections are common, a minority of patients will have a potentially life-threatening tropical infection.

•

The evaluation of an ill returned traveler requires a detailed travel history with an understanding of the geographic distribution of infections, risk factors for acquisition, incubation periods, clinical presentations, and appropriate laboratory investigations.

•

A syndromic approach to specific investigations, and to presumptive therapy pending laboratory confirmation of the diagnosis, is appropriate.

•

Travel is also a risk factor for acquisition of antimicrobial-resistant bacteria, such as those containing extended spectrum β-lactamases, that become part of the traveler's colonizing flora.

•

As a rule, malaria should be excluded in all travelers presenting with a fever who have visited the tropics.

[Antibiotic resistance of Salmonella spp strains isolated from blood cultures in Bukavu, Democratic Republic of the Congo]

Introduction

La fièvre typhoïde est un problème majeur de santé publique dans les pays en voie de développement jusqu'à ce jour à cause de la vétusté des infrastructures sanitaires et des circuits de distribution de l'eau presque inexistants. En RDC en général et à Bukavu en particulier, l'hémoculture est inaccessible à la majorité des patients. L'objectif de cette étude était d'évaluer la sensibilité de Salmonella spp aux antibiotiques couramment utilisés dans la prise en charge de la fièvre typhoïde à Bukavu.

Méthodes

Une étude transversale étalée sur 6 mois a était organisée. Tout malade suspect de la fièvre typhoïde a été sélectionné dans l'étude. L'hémoculture était faite systématiquement chez tout malade sélectionné. L'identification de la souche bactérienne et l'antibiogramme ont été réalisés par les méthodes conventionnelles. Les antibiotiques suivants ont été testés: amikacine, amoxicilline, augmentin, aeftazidime, ceftriaxone, cefuroxime, chloramphénicol, ciprofloxacine, cotrimoxazole, doxycycline, gentamicine, négram, norfloxacine.

Résultats

460 malades ont été sélectionnés dans l'étude. 144 (31,30%) hémocultures positives ont été observées. Salmonella spp était le germe le plus isolé (41,66%). Les souches de Salmonella spp isolées à Bukavu sont sensibles à la ciprofloxacine (91,7%), au ceftazidime (81,7%), ceftriaxone (80%), norfloxacine (80%), amikacine (76,6%) et au cefuroxime (73,3%). Elles restent résistantes aux autres molécules d'antibiotiques.

Conclusion

Ces résultats montrent une sensibilité diminuée à plupart des antibiotiques testés. Un test d'antibiogramme est requis en cas de fièvre typhoïde pour une meilleure prise en charge.

Enteric fever in Barcelona: Changing patterns of importation and antibiotic resistance

BACKGROUND

Enteric fever's incidence is decreasing among residents of high-income countries, although it's rising in travelers coming from low-resource endemic settings. The study's aim is to describe epidemiological, clinical and laboratory features of patients with enteric fever.

METHODS

Retrospective descriptive study of enteric fever cases diagnosed at a Tropical Medicine Unit in Barcelona, 1993-2012.

RESULTS

Out of 40 patients, 31(77,5%) were returning travelers, and 70% of them had been in Southern Asia. In the rest of patients without an antecedent of a recent travel, the infection occurred mainly before year 2000. The more frequently reported symptoms were fever and diarrhea, lacking significant differences between S. typhi and S. paratyphi infections. Quinolones were used as empiric treatment in 47.2% of patients, 36.1% received 3rd generation cephalosporins, 2.78% azithromycin and 13.89% other combinations. Resistance to quinolones in the S. paratyphi group (66.7%) was significantly higher compared with the S. typhi group (20%) (p:0.02). 22.5% of patients had treatment failure and 23.6% patients presented complications, none of them had been previously vaccinated.

CONCLUSIONS

The diagnosis of enteric fever was more frequent among travelers coming from Southern-East Asia. Quinolone resistance is widely spread, particularly in S. paratyphi serotypes and should not be considered as first choice treatment anymore.

Multidrug-resistant Salmonella enterica serotype Typhi, Gulf of Guinea Region, Africa

We identified 3 lineages among multidrug-resistant (MDR) Salmonella enterica serotype Typhi isolates in the Gulf of Guinea region in Africa during the 2000s. However, the MDR H58 haplotype, which predominates in southern Asia and Kenya, was not identified. MDR quinolone-susceptible isolates contained a 190-kb incHI1 pST2 plasmid or a 50-kb incN pST3 plasmid.

Epidemiology, Clinical Presentation, Laboratory Diagnosis, Antimicrobial Resistance, and Antimicrobial Management of Invasive Salmonella Infections

Salmonella enterica infections are common causes of bloodstream infection in low-resource areas, where they may be difficult to distinguish from other febrile illnesses and may be associated with a high case fatality ratio. Microbiologic culture of blood or bone marrow remains the mainstay of laboratory diagnosis. Antimicrobial resistance has emerged in Salmonella enterica, initially to the traditional first-line drugs chloramphenicol, ampicillin, and trimethoprim-sulfamethoxazole. Decreased fluoroquinolone susceptibility and then fluoroquinolone resistance have developed in association with chromosomal mutations in the quinolone resistance-determining region of genes encoding DNA gyrase and topoisomerase IV and also by plasmid-mediated resistance mechanisms. Resistance to extended-spectrum cephalosporins has occurred more often in nontyphoidal than in typhoidal Salmonella strains. Azithromycin is effective for the management of uncomplicated typhoid fever and may serve as an alternative oral drug in areas where fluoroquinolone resistance is common. In 2013, CLSI lowered the ciprofloxacin susceptibility breakpoints to account for accumulating clinical, microbiologic, and pharmacokinetic-pharmacodynamic data suggesting that revision was needed for contemporary invasive Salmonella infections. Newly established CLSI guidelines for azithromycin and Salmonella enterica serovar Typhi were published in CLSI document M100 in 2015.

Clinical and microbiological profile of a retrospective cohort of enteric fever in 2 Spanish tertiary hospitals

Enteric fever in high-income countries is diagnosed mainly in patients returning from endemic countries. We assess the clinical, microbiological, and prognosis aspects of enteric fever in 2 Spanish tertiary hospitals. A retrospective observational study was conducted at Vall d'Hebron University Hospital and Ramón y Cajal University Hospital in Spain. We reviewed medical records of all patients who were diagnosed with enteric fever from January 2000 to January 2014 at these hospitals. We identified 47 patients with enteric fever episodes. According to their travel history, 35 (74.5%) patients had travelled to highly endemic countries. Imported enteric fever was acquired mainly in Asia (70.3%). Imported infections were implicated in travelers (48.6%), visiting friends and relatives (40%) and immigrants (11.4%). We found that 12 patients were diagnosed with enteric fever without a travel history (autochthonous infection). The resistance profile of the isolates showed decreased ciprofloxacin susceptibility in 66.7% of the imported group and 8.3% of the autochthonous group (P = 0.001). Salmonella strains from patients returning from Asia had an increased risk of having decreased ciprofloxacin susceptibility (odds ratio, 52.25; 95% confidence interval: 8.6-317.7). Patients with imported enteric fever are at higher risk for having a Salmonella strain with decreased ciprofloxacin susceptibility, especially in patients returning from Asia. Initial treatment with third-generation cephalosporin or azithromycin is strongly recommended until a drug-susceptibility test is available. Prevention strategies such as pretravel counseling and immunization before travel may be beneficial.

Typhoid fever

Control of typhoid fever relies on clinical information, diagnosis, and an understanding for the epidemiology of the disease. Despite the breadth of work done so far, much is not known about the biology of this human-adapted bacterial pathogen and the complexity of the disease in endemic areas, especially those in Africa. The main barriers to control are vaccines that are not immunogenic in very young children and the development of multidrug resistance, which threatens efficacy of antimicrobial chemotherapy. Clinicians, microbiologists, and epidemiologists worldwide need to be familiar with shifting trends in enteric fever. This knowledge is crucial, both to control the disease and to manage cases. Additionally, salmonella serovars that cause human infection can change over time and location. In areas of Asia, multidrug-resistant Salmonella enterica serovar Typhi (S Typhi) has been the main cause of enteric fever, but now S Typhi is being displaced by infections with drug-resistant S enterica serovar Paratyphi A. New conjugate vaccines are imminent and new treatments have been promised, but the engagement of local medical and public health institutions in endemic areas is needed to allow surveillance and to implement control measures.

Characterization of non-classical quinolone resistance in Salmonella enterica serovar Typhi: Report of a novel mutation in gyrB gene and diagnostic challenges

Objective

To establish the relative importance of Salmonella enterica serovar Typhi with non-classical quinolone resistance.

Methods

Eight hundred and ninety-one isolates of S. Typhi, isolated between 2004 and 2011, were tested for antibiotic susceptibility determination using disc diffusion and E-test. The mechanisms of fluoroquinolone resistance were studied in a sub-set of the NAL^S (nalidixic acid susceptible) isolates by wave nucleic acid fragment analysis of PCR products from gyrA, gyrB, parC and parE and from the plasmid borne determinants: qnrA,B,S; aac(6′)-Ib-cr and qepA. To assess genetic relatedness multi-locus variable number tandem repeat analysis was carried out using five loci.

Results

Eighty isolates with a nalidixic acid MIC of <32 mg/L (NAL^S) and a ciprofloxacin MIC of >0.064 mg/L CIP^I (ciprofloxacin reduced susceptibility) were found. In 36 NAL^S CIP^I isolates two distinct genotypes were identified when compared with 16 susceptible controls: Group B (n = 34), mutation in gyrB at codon 464, NAL MIC of 3–12 mg/L and CIP MIC of 0.064–0.5 mg/L.; and Group C, mutation in gyrA at codon 83 (n = 2) NAL MIC of 16 mg/L and CIP MIC of 0.25–0.38 mg/L. Group B isolates were found in different strain backgrounds as defined by MLVA.

Conclusion

The use of nalidixic acid to screen for reduced susceptibility to fluoroquinolones in S. Typhi misses CIP^I-NAL^S isolates, an established phenotype in India.

Assessment of returning travellers with fever

Millions of people travel to the tropics each year and a significant minority of them become ill, either during their stay, or shortly after their return. Most have mild, self-limiting illnesses, but a few will have a life-threatening condition. This article outlines how to evaluate fever in the returning traveller and discusses important infection control and public health measures. A detailed travel history, which takes into account travel destinations, specific activities and risk factors in relation to the onset of symptoms, is essential for constructing a comprehensive list of differential diagnoses and guiding appropriate investigations. Importantly, all travellers returning from the tropics with a fever should be investigated for malaria, even if their return was 3 months ago or longer.

Ηepatitis A and enteric fever in Greece, 2004-2011: a cross-sectional analysis

BACKGROUND

In Greece the number of international travellers has increased significantly the past decade.

AIM

To study the impact of international travels on the epidemiology of hepatitis A and enteric fever in Greece.

METHODS

We studied cases of hepatitis A and enteric fever notified through the National Surveillance System from January 1, 2004 through December 31, 2011.

RESULTS

A total of 921 cases of hepatitis A and 106 cases of enteric fever were notified; of them, 88 (9.5%) and 46 (43.4%) were travel-associated, respectively. Travellers returning from Eastern Europe and the Middle East accounted for most imported cases of hepatitis A (37 (43.5%) and 14 (16.5%) cases, respectively). The Indian subcontinent was the prevalent area of acquisition of travel-associated enteric fever, followed by the Middle East (35 (83.3%) and 4 (9.5%) cases, respectively). Foreign-born travellers accounted for 43 (48.8%) and 39 (86.6%) cases of travel-associated hepatitis A and enteric fever, respectively. Children <15 years accounted for 65.1% of hepatitis A cases and 7.7% among foreign-born travellers. Greek Roma accounted for 270 (29.3%) of all hepatitis A cases notified.

CONCLUSIONS

International travels have a significant impact on the epidemiology of enteric fever in Greece, affecting mainly foreign travellers. Hepatitis A carries a significant burden of morbidity among Greek travellers and children of foreign nationality. There is a need to improve travel medicine services for travellers travelling to developing countries.

Comparative study of four time series methods in forecasting typhoid fever incidence in China

Accurate incidence forecasting of infectious disease is critical for early prevention and for better government strategic planning. In this paper, we present a comprehensive study of different forecasting methods based on the monthly incidence of typhoid fever. The seasonal autoregressive integrated moving average (SARIMA) model and three different models inspired by neural networks, namely, back propagation neural networks (BPNN), radial basis function neural networks (RBFNN), and Elman recurrent neural networks (ERNN) were compared. The differences as well as the advantages and disadvantages, among the SARIMA model and the neural networks were summarized and discussed. The data obtained for 2005 to 2009 and for 2010 from the Chinese Center for Disease Control and Prevention were used as modeling and forecasting samples, respectively. The performances were evaluated based on three metrics: mean absolute error (MAE), mean absolute percentage error (MAPE), and mean square error (MSE). The results showed that RBFNN obtained the smallest MAE, MAPE and MSE in both the modeling and forecasting processes. The performances of the four models ranked in descending order were: RBFNN, ERNN, BPNN and the SARIMA model.

Decreased ciprofloxacin susceptibility in Salmonella Typhi and Paratyphi infections in ill-returned travellers: the impact on clinical outcome and future treatment options

The emergence of decreased ciprofloxacin susceptibility (DCS) in Salmonella enterica serovar Typhi and serovar Paratyphi A, B or C limits treatment options. We studied the impact of DCS isolates on the fate of travellers returning with enteric fever and possible alternative treatment options. We evaluated the clinical features, susceptibility data and efficacy of empirical treatment in patients with positive blood cultures of a DCS isolate compared to patients infected with a ciprofloxacin-susceptible (CS) isolate in the period from January 2002 to August 2008. In addition, the pharmacokinetic and pharmacodynamic parameters of ciprofloxacin, levofloxacin and gatifloxacin were determined to assess if increasing the dose would result in adequate unbound fraction of the drug 24-h area under the concentration-time curve/minimum inhibitory concentration (ƒAUC(0-24)/MIC) ratio. Patients with DCS more often returned from the Indian subcontinent and had a longer fever clearance time and length of hospital stay compared to patients in whom the initial empirical therapy was adequate. The mean ƒAUC(0-24)/MIC was 41.3 ± 18.8 in the patients with DCS and 585.4 ± 219 in patients with a CS isolate. For DCS isolates, the mean ƒAUC0-24/MIC for levofloxacin was 60.5 ± 28.7 and for gatifloxacin, it was 97.9 ± 28.0. Increasing the dose to an adequate ƒAUC(0-24)/MIC ratio will lead to conceivably toxic drug levels in 50% of the patients treated with ciprofloxacin. Emerging DCS isolates has led to the failure of empirical treatment in ill-returned travellers. We demonstrated that, in some cases, an adequate ƒAUC(0-24)/MIC ratio could be achieved by increasing the dose of ciprofloxacin or by the use of alternative fluoroquinolones.

Vaccines for typhoid fever and other salmonelloses

PURPOSE OF REVIEW

This review summarizes the recent advances in vaccination against Salmonella enterica serovar Typhi and highlights the data supporting the development of next generation vaccines to address paratyphoid fever and invasive nontyphoidal Salmonella (iNTS) disease.

RECENT FINDINGS

There has been increasing awareness of the disease burden caused by S. Typhi particularly in Africa and greater recognition of S. Paratyphi A's contribution to enteric fever episodes throughout Asia. Groups have been working to improve the existing typhoid vaccines and provide comprehensive data on the feasibility of their implementation in endemic settings. These data have resulted in modifications to the recommendations for typhoid vaccination in traveller markets and endemic settings, and has also led to the development of S. Paratyphi A vaccine components that can be combined with existing typhoid vaccines to generate bivalent formulations against enteric fever. The epidemiology of iNTS serovars as cause of appreciable morbidity and mortality in Africa, and the need for vaccines, has also become more widely appreciated.

SUMMARY

Current typhoid vaccines, although moderately effective for short periods of time, cannot be used in all age groups and only target one of the clinically relevant Salmonella serovars. Greater effort must be placed on the development and implementation of improved vaccines for the disease burden resulting from Typhi, Paratyphi A or iNTS infections.

Schools as potential vaccination venue for vaccines outside regular EPI schedule: results from a school census in Pakistan

Background

Vaccines are the most effective public health intervention. Expanded Program on Immunization (EPI) provides routine vaccination in developing countries. However, vaccines that cannot be given in EPI schedule such as typhoid fever vaccine need alternative venues. In areas where school enrolment is high, schools provide a cost effective opportunity for vaccination. Prior to start of a school-based typhoid vaccination program, interviews were conducted with staff of educational institutions in two townships of Karachi, Pakistan to collect baseline information about the school system and to plan a typhoid vaccination program. Data collection teams administered a structured questionnaire to all schools in the two townships. The administrative staff was requested information on school fee, class enrolment, past history of involvement and willingness of parents to participate in a vaccination campaign.

Results

A total of 304,836 students were enrolled in 1,096 public, private, and religious schools (Madrasahs) of the two towns. Five percent of schools refused to participate in the school census. Twenty-five percent of schools had a total enrolment of less than 100 students whereas 3% had more than 1,000 students. Health education programs were available in less than 8% of public schools, 17% of private schools, and 14% of Madrasahs. One-quarter of public schools, 41% of private schools, and 43% of Madrasahs had previously participated in a school-based vaccination campaign. The most common vaccination campaign in which schools participated was Polio eradication program. Cost of the vaccine, side effects, and parents' lack of information were highlighted as important limiting factors by school administration for school-based immunization programs. Permission from parents, appropriateness of vaccine-related information, and involvement of teachers were considered as important factors to improve participation.

Conclusions

Health education programs are not part of the regular school curriculum in developing countries including Pakistan. Many schools in the targeted townships participated in immunization activities but they were not carried out regularly. In the wake of low immunization coverage in Pakistan, schools can be used as a potential venue not only for non-EPI vaccines, but for a catch up vaccination of routine vaccines.

Salmonella infections: an update on epidemiology, management, and prevention

Salmonella species are a group of Gram-negative enterobacteria and known human pathogens in developing as well as industrialized countries. Despite significant advances in sanitation, provision of potable water, and highly controlled food chain surveillance, transmission of Salmonella spp. continues to affect communities, preferentially children, worldwide. This review summarizes updated concepts on typhoidal and non-typhoidal Salmonella infections, starting with a historical perspective that implicates typhoid Salmonella as a significant human pathogen since ancient times. We describe the epidemiology of this pathogen with emphasis on the most recent non-typhoidal Salmonella outbreaks in industrialized countries and continued outbreaks of typhoid Salmonella in underserved countries. An overview of clinical aspects of typhoid and non-typhoid infections in developing and industrialized countries, respectively, is provided, followed by a description on current treatment concepts and challenges treating multidrug-resistant Salmonella infections. We conclude with prevention recommendations, and recent research studies on vaccine prevention.

Fluoroquinolones for treating typhoid and paratyphoid fever (enteric fever)

BACKGROUND

Typhoid and paratyphoid are febrile illnesses, due to a bacterial infection, which remain common in many low- and middle-income countries. The World Health Organization (WHO) currently recommends the fluoroquinolone antibiotics in areas with known resistance to the older first-line antibiotics.

OBJECTIVES

To evaluate fluoroquinolone antibiotics for treating children and adults with enteric fever.

SEARCH STRATEGY

We searched The Cochrane Infectious Disease Group Specialized Register (February 2011); Cochrane Central Register of Controlled Trials (CENTRAL), published in The Cochrane Library (2011, Issue 2); MEDLINE (1966 to February 2011); EMBASE (1974 to February 2011); and LILACS (1982 to February 2011). We also searched the metaRegister of Controlled Trials (mRCT) in February 2011.

SELECTION CRITERIA

Randomized controlled trials examining fluoroquinolone antibiotics, in people with blood, stool or bone marrow culture-confirmed enteric fever.

DATA COLLECTION AND ANALYSIS

Two authors independently assessed the trial's methodological quality and extracted data. We calculated risk ratios (RR) for dichotomous data and mean difference for continuous data with 95% confidence intervals (CI).Comparative effectiveness has been interpreted in the context of; length of treatment, dose, year of study, known levels of antibiotic resistance, or proxy measures of resistance such as the failure rate in the comparator arm.

MAIN RESULTS

Twenty-six studies, involving 3033 patients, are included in this review.Fluoroquinolones versus older antibiotics (chloramphenicol, co-trimoxazole, amoxicillin and ampicillin)In one study from Pakistan in 2003-04, high clinical failure rates were seen with both chloramphenicol and co-trimoxazole, although resistance was not confirmed microbiologically. A seven-day course of either ciprofloxacin or ofloxacin were found to be superior. Older studies of these comparisons failed to show a difference (six trials, 361 participants).In small studies conducted almost two decades ago, the fluoroquinolones were demonstrated to have fewer clinical failures than ampicillin and amoxicillin (two trials, 90 participants, RR 0.11, 95% CI 0.02 to 0.57).Fluoroquinolones versus current second-line options (ceftriaxone, cefalexin, and azithromycin)The two studies comparing a seven day course of oral fluoroquinolones with three days of intravenous ceftriaxone were too small to detect important differences between antibiotics should they exist (two trials, 89 participants).In Pakistan in 2003-04, no clinical or microbiological failures were seen with seven days of either ciprofloxacin, ofloxacin or cefixime (one trial, 139 participants). In Nepal in 2005, gatifloxacin reduced clinical failure and relapse compared to cefixime, despite a high prevalence of NaR in the study population (one trial, 158 participants, RR 0.04, 95% CI 0.01 to 0.31).Compared to a seven day course of azithromycin, a seven day course of ofloxacin had a higher rate of clinical failures in populations with both multi-drug resistance (MDR) and nalidixic acid resistance (NaR) enteric fever in Vietnam in 1998-2002 (two trials, 213 participants, RR 2.20, 95% CI 1.23 to 3.94). However, a more recent study from Vietnam in 2004-05, detected no difference between gatifloxacin and azithromycin with both drugs performing well (one trial, 287 participants).

AUTHORS' CONCLUSIONS

Generally, fluoroquinolones performed well in treating typhoid, and maybe superior to alternatives in some settings. However, we were unable to draw firm general conclusions on comparative contemporary effectiveness given that resistance changes over time, and many studies were small. Policy makers and clinicians need to consider local resistance patterns in choosing a fluoroquinolone or alternative.There is some evidence that the newest fluoroquinolone, gatifloxacin, remains effective in some regions where resistance to older fluoroquinolones has developed. However, the different fluoroquinolones have not been compared directly in trials in these settings.

The influence of reduced susceptibility to fluoroquinolones in Salmonella enterica serovar Typhi on the clinical response to ofloxacin therapy

Background

Infection with Salmonella enterica serovar Typhi (S. Typhi) with reduced susceptibility to fluoroquinolones has been associated with fluoroquinolone treatment failure. We studied the relationship between ofloxacin treatment response and the ofloxacin minimum inhibitory concentration (MIC) of the infecting isolate. Individual patient data from seven randomised controlled trials of antimicrobial treatment in enteric fever conducted in Vietnam in which ofloxacin was used in at least one of the treatment arms was studied. Data from 540 patients randomised to ofloxacin treatment was analysed to identify an MIC of the infecting organism associated with treatment failure.

Principal Findings

The proportion of patients failing ofloxacin treatment was significantly higher in patients infected with S. Typhi isolates with an MIC≥0.25 µg/mL compared with those infections with an MIC of ≤0.125 µg/mL (p<0.001). Treatment success was 96% when the ofloxacin MIC was ≤0.125 µg/mL, 73% when the MIC was between 0.25 and 0.50 µg/mL and 53% when the MIC was 1.00 µg/mL. This was despite a longer duration of treatment at a higher dosage in patients infected with isolates with an MIC≥0.25 µg/mL compared with those infections with an MIC of ≤0.125 µg/mL.

Significance

There is a clear relationship between ofloxacin susceptibility and clinical outcome in ofloxacin treated patients with enteric fever. An ofloxacin MIC of ≥0.25 µg/mL, or the presence of nalidixic acid resistance, can be used to define S. Typhi infections in which the response to ofloxacin may be impaired.

Typhoid fever is an infection of the bloodstream caused by the organism Salmonella Typhi (S. Typhi). Treatment with antimicrobials is critical for preventing severe infection and even death, yet antimicrobial resistant organisms have become a problem in many places where typhoid is common. Fluoroquinolones are a group of antimicrobials that are commonly used to treat typhoid, we analysed data from 540 enteric fever patients treated with ofloxacin (a fluoroquinolone) to identify a level of resistance (minimum inhibitory concentration (MIC)) from the infecting organism which is associated with treatment failure. The proportion of patients failing treatment was higher in those infected with a bacterium with an MIC≥0.25 µg/mL, compared with those infections with an MIC of ≤0.125 µg/mL. Treatment success was 96% when the ofloxacin MIC was ≤0.125 µg/mL, yet only 53% when the MIC was 1.00 µg/mL. Our data demonstrates that an S. Typhi bacterium with an ofloxacin MIC of ≥0.25 µg/mL correlates with a poor outcome when treated with this antimicrobial. Therefore, we propose an amendment in the current MIC guidelines for microbiology laboratories to aid clinicians treating typhoid and suggest the use of alternative therapy in these patients.

Salmonella entericaSerotype Typhi with Nonclassical Quinolone Resistance Phenotype

We report Salmonella enterica serotype Typhi strains with a nonclassical quinolone resistance phenotype (i.e., decreased susceptibility to ciprofloxacin but with susceptibility to nalidixic acid) associated with a nonsynonymous mutation at codon 464 of the gyrB gene. These strains, not detected by the nalidixic acid disk screening test, can result in fluoroquinolone treatment failure.

Epidemiology, antibiotic resistance trends and the cost of enteric fever in East London, 2005-2010

INTRODUCTION

Enteric fever seen in the UK has usually been acquired abroad. The cost to the NHS of treating enteric fever cases is not known. Data on the epidemiology of enteric fever, inpatient treatment costs and the public health management is needed to make decisions regarding the cost benefit considerations of introducing targeted prevention strategies.

METHODS

A retrospective study of laboratory confirmed enteric fever cases was conducted to estimate the cost of inpatient treatment and to determine antimicrobial resistance patterns at two hospitals in East London between January 2005 and the end of August 2010.

RESULTS

138 cases of enteric fever were identified during the study period (90 S.ser.Typhi and 48 S. ser. Paratyphi). 92% had a recent history of foreign travel, 57% had travelled to visit friends and relatives (VFRs), 26% sought pre-travel health advice and 26% of patients had received typhoid vaccination. The inpatient treatment cost of 138 cases to the NHS was £272,747. The proportion of isolates with high level ciprofloxacin resistance (MICs>1 mg/L) has increased from 10% in 2006 to 30% in 2010. Our data also shows the emergence of isolates with high azithromycin MICs (>32 mg/L); 60% (six out of ten) isolates tested in July-August 2010.

CONCLUSIONS

There is a significant direct cost of treating enteric fever cases on the NHS. Cost reduction measures are confined due to the lack of effective oral antibiotics following the emergence of high level resistance to ciprofloxacin and azithromycin. Outpatient parenteral antibiotic therapy service and improved preventative public health measures aimed at VFR travellers in particular may be helpful in reducing costs.

Continuing challenge of infectious diseases in India

In India, the range and burden of infectious diseases are enormous. The administrative responsibilities of the health system are shared between the central (federal) and state governments. Control of diseases and outbreaks is the responsibility of the central Ministry of Health, which lacks a formal public health department for this purpose. Tuberculosis, malaria, filariasis, visceral leishmaniasis, leprosy, HIV infection, and childhood cluster of vaccine-preventable diseases are given priority for control through centrally managed vertical programmes. Control of HIV infection and leprosy, but not of tuberculosis, seems to be on track. Early success of malaria control was not sustained, and visceral leishmaniasis prevalence has increased. Inadequate containment of the vector has resulted in recurrent outbreaks of dengue fever and re-emergence of Chikungunya virus disease and typhus fever. Other infectious diseases caused by faecally transmitted pathogens (enteric fevers, cholera, hepatitis A and E viruses) and zoonoses (rabies, leptospirosis, anthrax) are not in the process of being systematically controlled. Big gaps in the surveillance and response system for infectious diseases need to be addressed. Replication of the model of vertical single-disease control for all infectious diseases will not be efficient or viable. India needs to rethink and revise its health policy to broaden the agenda of disease control. A comprehensive review and redesign of the health system is needed urgently to ensure equity and quality in health care. We recommend the creation of a functional public health infrastructure that is shared between central and state governments, with professional leadership and a formally trained public health cadre of personnel who manage an integrated control mechanism of diseases in districts that includes infectious and non-infectious diseases, and injuries.

Changing Epidemiology of Enteric Fevers in Singapore

Introduction: We studied the epidemiological trends of enteric fevers (typhoid and paratyphoid fever) in Singapore from 1990 to 2009 and carried out a review of the current prevention and control measures. Materials and Methods: Epidemiological records of all reported enteric fevers maintained by the Communicable Diseases Division, Ministry of Health from 1990 to 2009 were analysed. Results: A total of 2464 laboratory confirmed cases of enteric fevers (1699 cases of typhoid and 765 cases of paratyphoid) were reported. Of these, 75% were imported, mainly from India and Indonesia. There had been a significant fall in the mean annual incidence rate of indigenous enteric fevers from 4.3 per 100,000 population in 1990 to 0.26 per 100,000 population in 2009 (P <0.005) with a corresponding increase in the proportion of imported cases from 71% between 1990 and 1993 to 92% between 2006 and 2009 (P <0.0005). Imported cases involving foreign contract workers increased significantly from 12.8% between 1990 and 1993 to 40.4% between 2006 and 2009 (P <0.0005). Conclusion: Singapore has experienced a marked decline in the incidence of enteric fevers that is now comparable to that of other developed countries. Continued vigilance and proactive measures that address the changing epidemiology of enteric fevers in Singapore are necessary to sustain the milestone achieved in the past 2 decades. Keywords: Imported Cases, Outbreaks, Paratyphoid, Typhoid

Suitable disk antimicrobial susceptibility breakpoints defining Salmonella enterica serovar Typhi isolates with reduced susceptibility to fluoroquinolones

Infections with Salmonella enterica serovar Typhi isolates that have reduced susceptibility to ofloxacin (MIC ≥ 0.25 μg/ml) or ciprofloxacin (MIC ≥ 0.125 μg/ml) have been associated with a delayed response or clinical failure following treatment with these antimicrobials. These isolates are not detected as resistant using current disk susceptibility breakpoints. We examined 816 isolates of S. Typhi from seven Asian countries. Screening for nalidixic acid resistance (MIC ≥ 16 μg/ml) identified isolates with an ofloxacin MIC of ≥0.25 μg/ml with a sensitivity of 97.3% (253/260) and specificity of 99.3% (552/556). For isolates with a ciprofloxacin MIC of ≥0.125 μg/ml, the sensitivity was 92.9% (248/267) and specificity was 98.4% (540/549). A zone of inhibition of ≤28 mm around a 5-μg ofloxacin disc detected strains with an ofloxacin MIC of ≥0.25 μg/ml with a sensitivity of 94.6% (246/260) and specificity of 94.2% (524/556). A zone of inhibition of ≤30 mm detected isolates with a ciprofloxacin MIC of ≥0.125 μg/ml with a sensitivity of 94.0% (251/267) and specificity of 94.2% (517/549). An ofloxacin MIC of ≥0.25 μg/ml and a ciprofloxacin MIC of ≥0.125 μg/ml detected 74.5% (341/460) of isolates with an identified quinolone resistance-inducing mutation and 81.5% (331/406) of the most common mutant (carrying a serine-to-phenylalanine mutation at codon 83 in the gyrA gene). Screening for nalidixic acid resistance or ciprofloxacin and ofloxacin disk inhibition zone are suitable for detecting S. Typhi isolates with reduced fluoroquinolone susceptibility.

Salmonella sepsis simulating gastrointestinal ischaemia following cardiopulmonary bypass

Cardiac surgery is commonly associated with gastrointestinal complications. The incidence of severe abdominal pathology ranges from 0.5% to 3% and is associated with a 30% risk of mortality. Frequently occurring complications include splanchnic infarction, perforated bowel, pancreatitis, upper intestinal bleeding and diverticulitis. Systemic and localised infections are also common after open heart surgery. Plasma proteins, neutrophils, monocytes, endothelial cells and lymphocytes are all altered by cardiopulmonary bypass (CPB). Cell mediated immunity is depressed following exposure to the extra-corporeal circuit leading to an increased susceptibility and vulnerability to pathogens. Typhoid fever is the systemic manifestation of Salmonella typhi septicaemia. Its presentation can be similar to that of abdominal ischaemia making the diagnosis of this potentially fatal multi-systemic illness challenging. We report a fatal case of salmonella septicaemia convincingly masquerading as mesenteric ischaemia following routine CPB.

Imported enteric fever: case series from the hospital for tropical diseases, London, United Kingdom

Our current knowledge of the clinical characteristics of enteric fever is drawn mainly from population-based studies in disease-endemic countries, and there are limited data published on cases in returning travelers. We report the clinical characteristics of enteric fever in 92 travelers returning to London, United Kingdom. Salmonella typhi and S. paratyphi resulted in an almost indistinguishable clinical picture. Rose spots and relative bradycardia were found only in a few patients. A total of 91% of the patients had a normal leukocyte count, which was associated with a markedly increased level of alanine aminotransferase in 82%. A total of 57% of the S. typhi isolates had decreased susceptibility to ciprofloxacin and resistance to nalidixic acid; these isolates were from southern Asia. Thirty percent were multidrug resistant; all were from southern Asia and Nigeria. None of the paratyphoid isolates were multidrug resistant but rates of decreased susceptibility to fluoroquinolones were higher than in S. typhi (74%).

A multiplex single nucleotide polymorphism typing assay for detecting mutations that result in decreased fluoroquinolone susceptibility in Salmonella enterica serovars Typhi and Paratyphi A

Objectives

Decreased susceptibility to fluoroquinolones has become a major problem for the successful therapy of human infections caused by Salmonella enterica, especially the life-threatening typhoid and paratyphoid fevers.

Methods

By using Luminex xTAG beads, we developed a rapid, reliable and cost-effective multiplexed genotyping assay for simultaneously detecting 11 mutations in gyrA, gyrB and parE of S. enterica serovars Typhi and Paratyphi A that result in nalidixic acid resistance (Nal^R) and/or decreased susceptibility to fluoroquinolones.

Results

This assay yielded unambiguous single nucleotide polymorphism calls on extracted DNA from 292 isolates of Salmonella Typhi (Nal^R = 223 and Nal^S = 69) and 106 isolates of Salmonella Paratyphi A (Nal^R = 24 and Nal^S = 82). All of the 247 Nal^RSalmonella Typhi and Salmonella Paratyphi A isolates were found to harbour at least one of the target mutations, with GyrA Phe-83 as the most common one (143/223 for Salmonella Typhi and 18/24 for Salmonella Paratyphi A). We also identified three GyrB mutations in eight Nal^SSalmonella Typhi isolates (six for GyrB Phe-464, one for GyrB Leu-465 and one for GyrB Asp-466), and mutations GyrB Phe-464 and GyrB Asp-466 seem to be related to the decreased ciprofloxacin susceptibility phenotype in Salmonella Typhi. This assay can also be used directly on boiled single colonies.

Conclusions

The assay presented here would be useful for clinical and reference laboratories to rapidly screen quinolone-resistant isolates of Salmonella Typhi and Salmonella Paratyphi A, and decipher the underlying genetic changes for epidemiological purposes.

Characterization of antimicrobial resistance, molecular and phage types ofSalmonella entericaserovar Typhi isolations

Isolation rates in Canada ofSalmonella entericaserovar Typhi increased from 0·29 to 0·55 isolations/100 000 population during 2000–2006. Although no ciprofloxacin resistance was detected, nalidixic acid resistance increased from 41% to 80%. Multidrug-resistantS. Typhi represented 18% of the strains tested. Pulsed-field gel electrophoresis (PFGE) analysis of 222 isolates resulted in 91 distinct patterns clustering into four major genetic similarity groups. The five most frequently occurring PFGE patterns accounted for 46% of the isolates. Drug-resistant isolates predominantly occurred in one PFGE similarity group. There were 39 phage types identified in 826 isolates analysed with 60% described by five phage types; 134 were untypable. The phage types associated with multidrug resistance were phage types 53, B1, D1, E1, E9, G3 and M1. Improved integration of epidemiological and laboratory case data will facilitate the protection of public health in Canada during an era of increasing travel and globalization.

Enteric fever in a UK regional infectious diseases unit: a 10 year retrospective review

INTRODUCTION

Enteric fever is an increasingly common diagnosis in returning travellers in the UK.

METHODS

We performed a retrospective descriptive study of culture-confirmed cases of enteric fever admitted to University Hospitals Leicester, UK between January 1999 and April 2009.

RESULTS

100 cases of enteric fever were identified in adults (n = 76) and children (n = 24). The median age of adult subjects was 38 (range 18-71) and 55% were male. Of the 61 adult cases with notes available, 60 (98.3%) were of Asian ethnicity and 56 (92%) had a recent travel history, principally to the Indian Subcontinent. Symptoms included fever (100%), headache (62%), diarrhoea (59%) and abdominal pain (44%). Common examination findings included pyrexia and mild generalized abdominal tenderness. Mild hyponatraemia, transaminitis and a normal white cell count were commonly identified. Reduced ciprofloxacin sensitivity was common and increased over the study period. Median fever clearance time was 6 days, and treatment failure occurred in 20% of cases. Relapse occurred in 2 patients. Complications were unusual, and one patient died.

DISCUSSION

Patients with enteric fever presented with a non-specific febrile illness within one month after returning from travel, and most had an uncomplicated clinical course. Increasing ciprofloxacin insensitivity was the likely explanation for a high treatment failure rate and this agent can no longer recommended as empirical treatment.

Fever in returned travellers presenting in the United Kingdom: recommendations for investigation and initial management

International travel is increasing. Most physicians and general practitioners will encounter returned travellers with fever and the majority of travel-related infection is associated with travel to the tropics. In those returning from the tropics malaria must always be excluded, and HIV considered, from all settings. Common causes of non-malarial fever include from Africa rickettsial diseases, amoebic liver abscess and Katayama syndrome; from South and South East Asia, enteric fever and arboviral infection; from the Middle East, brucellosis and from the Horn of Africa visceral leishmaniasis. Other rare but important diseases from particular geographical areas include leptospirosis, trypanosomiasis and viral haemorrhagic fever. North and South America, Europe and Australia also have infections which are geographically concentrated. Empirical treatment may have to be started based on epidemiological probability of infection whilst waiting for results to return. The evidence base for much of the management of tropical infections is limited. These recommendations provide a pragmatic approach to the initial diagnosis and management of fever in returned travellers, based on evidence where it is available and on consensus of expert opinion where it is not. With early diagnosis and treatment the majority of patients with a potentially fatal infection related to travel will make a rapid and full recovery.

Increasing rates and clinical consequences of nalidixic acid-resistant isolates causing enteric fever in returned travellers: an 18-year experience

The purpose of this study was to examine the rate and clinical consequences of nalidixic acid-resistant (NAR) isolates in travellers with enteric fever presenting to a hospital in a developed country. We retrospectively examined microbiologically confirmed cases of enteric fever in adult returned travellers over an 18-year period presenting to two tertiary referral hospitals in Melbourne, Australia. There were 59 cases of Salmonella typhi infection, 43 cases of S. paratyphi A infection and two cases of S. paratyphi B infection. Most patients reported recent travel to India (36%) or Indonesia (29%). NAR isolates were commonly encountered (41% of all isolates), particularly from India (75%), Pakistan (80%) and Bangladesh (60%). The number of NAR isolates increased progressively after 2003. Patients with NAR isolates had prolonged mean fever clearance time (5.6 vs. 3.3 days, P = 0.03) and prolonged hospital stay (7.9 vs. 5.7 days, P = 0.02) compared to non-resistant isolates. This represents the largest report of NAR enteric fever in returned travellers. NAR isolates predominate in cases of enteric fever from South Asia and result in prolonged fever clearance time and hospital stay. Empiric therapy with alternative antibiotics such as ceftriaxone or azithromycin should be considered in patients with suspected enteric fever from this region.

Fever, a blue hand, and abducens nerve paralysis in a returning traveler

Fever, caused by Salmonella typhi, is the cause of significant morbidity worldwide. Extraintestinal manifestations of typhoid fever can confuse clinicians in Western countries, delaying diagnosis. We present an extraordinary case of typhoid fever, manifesting as hand cyanosis as well as abducens nerve paresis, all of which promptly resolved with antibiotics.

Chronic disease mortality associated with infectious agents: a comparative cohort study of migrants from the Former Soviet Union in Israel and Germany

BACKGROUND

Prevalence of infectious diseases in migrant populations has been addressed in numerous studies. However, information is sparse on their mortality due to chronic diseases that are aetiologically associated with an infectious agent. This study investigates mortality related to infectious diseases with a specific focus on cancers of possibly infectious origin in voluntary migrants from the Former Soviet Union residing in Israel and in Germany.

METHODS

Both groups of migrants arrived from the Former Soviet Union in their destination countries between 1990 and 2001. Population-based data on migrants in Israel were obtained from the Israel Central Bureau of Statistics. Data for migrants in Germany were obtained from a representative sample of all migrants from the Former Soviet Union in Germany. Cause of death information was available until 2003 for the Israeli cohort and until 2005 for the German cohort. Standardized mortality ratios were calculated relative to the destination country for selected causes of death for which infectious agents may be causally involved. Multivariate Poisson regression was applied to assess differences in mortality by length of residence in the host country.

RESULTS

Both in Israel and in Germany these migrants have lower overall mortality than the population in their destination countries. However, they have significantly elevated mortality from viral hepatitis and from stomach and liver cancer when compared to the destination populations. Regression analysis shows that in Israel stomach cancer mortality is significantly higher among migrants at shorter durations of residence when compared to durations of more than nine years.

CONCLUSION

Higher mortality from cancers associated with infection and from viral hepatitis among migrants from the Former Soviet Union might result from higher prevalence of infections which were acquired in earlier years of life. The results highlight new challenges posed by diseases of infectious origin in migrants and call attention to the link between communicable and non-communicable diseases.

Clinical response and outcome of infection with Salmonella enterica serotype Typhi with decreased susceptibility to fluoroquinolones: a United States foodnet multicenter retrospective cohort study

Patients with typhoid fever due to Salmonella enterica serotype Typhi strains for which fluoroquinolones MICs are elevated yet that are classified as susceptible by the current interpretive criteria of the Clinical and Laboratory Standards Institute may not respond adequately to fluoroquinolone therapy. Patients from seven U.S. states with invasive Salmonella serotype Typhi infection between 1999 and 2002 were enrolled in a multicenter retrospective cohort study. Patients infected with Salmonella serotype Typhi isolates with ciprofloxacin MICs of 0.12 to 1 microg/ml (decreased ciprofloxacin susceptibility but not resistant to ciprofloxacin [DCS]) were compared with patients infected with isolates with ciprofloxacin MICs <0.12 microg/ml for fever clearance time and treatment failure. Of 71 patients, 30 (43%) were female and 24 (34%) were infected with Salmonella serotype Typhi with DCS; the median age was 14 years (range, 1 to 51 years). Twenty-one (88%) of 24 isolates with DCS were resistant to nalidixic acid. The median antimicrobial-related fever clearance times in the DCS and non-DCS groups were 92 h (range, 21 to 373 h) and 72 h (range, 19 to 264 h) (P = 0.010), respectively, and the fluoroquinolone-related fever clearance times in the DCS and non-DCS groups were 90 h (range, 9 to 373 h) and 64 h (range, 34 to 204 h) (P = 0.153), respectively. Four (17%) of 24 patients in the DCS group and 2 (4%) of 46 patients in the non-DCS group (relative risk, 2.5; 95% confidence interval, 1.2 to 5.1) experienced treatment failure. Associations persisted after adjustment for potential confounders. We demonstrate that patients infected with Salmonella serotype Typhi isolates with DCS show evidence of a longer time to fever clearance and more frequent treatment failure. Nalidixic acid screening does not detect all isolates with DCS.