Typhoid and paratyphoid fever: a 10-year retrospective study of 41 cases in a Parisian hospital

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.

Fiebre al regreso de un viaje a un país tropical

La fiebre es una causa frecuente de consulta después de regresar de un viaje a un país tropical. El punto clave es preguntar al paciente sobre los detalles del viaje y caracterizar los signos clínicos, incluida la fiebre, con la mayor precisión posible. Las principales causas de fiebre después de regresar de un viaje a un país tropical son el paludismo, las infecciones digestivas, las infecciones respiratorias y urinarias, y las patologías de la piel. Es esencial y urgente descartar el paludismo, cualesquiera que sean los síntomas asociados. Deberían considerarse otras posibles etiologías en función del plazo de aparición de la fiebre en relación con el período de incubación, los signos asociados y los resultados de las pruebas complementarias iniciales. Por último, no hay que pasar por alto una infección comunitaria o cosmopolita con un grave potencial evolutivo.

Epidemiological and Clinical Features of Salmonella Typhi Infection Among Adult Patients in Qatar: A Hospital-based Study

Objectives

We sought to describe the epidemiological and clinical features of typhoid fever in Qatar.

Methods

We conducted a retrospective study of adult patients treated for typhoid fever at Hamad General Hospital and Alkhor Hospital between 2005 and 2012.

Results

The mean age of the 354 patients enrolled in the study was 28.4±9.3 years; 296 (83.6%) were males. There were 42, 48, 39, 44, 46, 47, 52, and 36 cases of adults with typhoid fever in 2005, 2006, 2007, 2008, 2009, 2010, 2011, and 2012, respectively. Overall, 343 (96.9%) patients had a history of travel to endemic areas. Among them, 93.0% acquired typhoid fever in the Indian subcontinent. Fever was observed in all cases, and the other predominant symptoms were abdominal pain (38.1%), diarrhea (35.6%), and headache (33.1%). Salmonella typhi, showed high resistance to ciprofloxacin (n = 163; 46.0%), and low resistance to ceftriaxone (n = 2; 0.6%). Four patients developed intestinal perforation, which was surgically repaired in two cases. Two patients (0.6%) died.

Conclusions

Typhoid fever was frequent among immigrants to endemic areas. Travelers returning from endemic areas with suspected typhoid fever should be treated empirically with third-generation cephalosporin after obtaining appropriate cultures. Moreover, preventive measurements such as education on food and water hygiene, and effective vaccination of travelers should be practiced widely among travelers to endemic areas to reduce morbidity and mortality.

Febbre al ritorno da un viaggio in un paese tropicale

La febbre è una causa frequente di visita al ritorno da un viaggio in un paese tropicale. Il punto chiave è interrogare il paziente circa i dettagli del suo viaggio e caratterizzare al meglio i segni clinici, tra cui la febbre. Le principali cause di febbre al ritorno da un viaggio in un paese tropicale sono la malaria, le infezioni gastrointestinali, le infezioni respiratorie e urinarie e le patologie cutanee. È fondamentale e urgente escludere la malaria, a prescindere dai sintomi associati. Le altre possibili eziologie devono essere considerate in funzione del ritardo di comparsa della febbre rispetto al tempo di incubazione, dei segni associati e dei risultati degli esami di laboratorio iniziali. Infine, non si deve trascurare un’infezione comunitaria o cosmopolita a potenziale evolutivo grave.

Enteric fever among children: 50 cases in a French tertiary care centre

BACKGROUND

Enteric fever in France is primarily travel-associated. Characteristics of paediatric cases are scarce and information from field studies in endemic countries might not be generalizable to non-endemic countries.

METHODS

In this retrospective study, we reviewed all cases of typhoid and paratyphoid fever treated in a French paediatric tertiary care centre from 1993 to 2015.

RESULTS

Fifty cases of enteric fever due to Salmonella enterica serovar Typhi (n = 44) and Paratyphi (n = 6) were identified. Sixty-one percent of the children had travelled to Africa and 34% to the Indian subcontinent. Among travel-associated cases, 85% were visiting friends and relatives (VFR). Ninety-six percent had high fever associated with gastrointestinal symptoms. Anaemia (66%), elevated C-reactive protein (80%), transaminitis (87%) and mild hyponatremia (50%) were the main biological findings. Blood cultures were positive in 90% of cases. Twelve strains (24%) were resistant at least to one antibiotic, and all of them had been isolated since 2003, increasing the resistance rate during this last period to 43% (12/28). Ceftriaxone was administered to 71 patients for a median duration of 6 days (interquartile range (IQR): 4-8). The median time to apyrexia after the onset of treatment was 4 days (IQR: 2-5 days). Complications occurred in nine children with five (10%) presenting neurologic disorders. All 50 patients recovered.

CONCLUSION

In France, paediatric enteric fever is mainly a travel-associated disease and occurs in patients returning from a prolonged stay in an endemic area. Children VFR are at high risk and should be a priority target group for pre-travel preventive measures. The increase in antibiotic resistance reflects the situation in endemic countries and is a major concern.

Laboratory-acquired infections of Salmonella enterica serotype Typhi in South Africa: phenotypic and genotypic analysis of isolates

BACKGROUND

Workers in clinical microbiology laboratories are exposed to a variety of pathogenic microorganisms. Salmonella species is among the most commonly reported bacterial causes of laboratory-acquired infections. We report on three cases of laboratory-acquired Salmonella enterica serotype Typhi (Salmonella Typhi) infection which occurred over the period 2012 to 2016 in South Africa.

METHODS

Laboratory investigation included phenotypic and genotypic characterization of isolates. Phenotypic analysis included standard microbiological identification techniques, serotyping and antimicrobial susceptibility testing. Genotypic analysis included the molecular subtyping methodologies of pulsed-field gel electrophoresis analysis, multilocus sequence typing and whole-genome sequencing (WGS); with WGS data analysis including phylogenetic analysis based upon comparison of single nucleotide polymorphism profiles of isolates.

RESULTS

All cases of laboratory-acquired infection were most likely the result of lapses in good laboratory practice and laboratory safety. The following critical issues were highlighted. There was misdiagnosis and misreporting of Salmonella Typhi as nontyphoidal Salmonella by a diagnostic laboratory, with associated public health implications. We highlight issues concerning the importance of accurate fluoroquinolone susceptibility testing and interpretation of results according to updated guidelines. We describe potential shortcomings of a single disk susceptibility screening test for fluoroquinolone susceptibility and suggest that confirmatory minimum inhibitory concentration testing should always be performed in cases of invasive Salmonella infections. These antimicrobial susceptibility testing issues resulted in inappropriate ciprofloxacin therapy which may have been responsible for failure in clearance of pathogen from patients. Salmonella Typhi capsular polysaccharide vaccine was not protective in one case, possibly secondarily to a faulty vaccine.

CONCLUSIONS

Molecular subtyping of isolates proved effective to investigate the genetic relatedness of isolates. Molecular subtyping data interpreted together with epidemiological data allowed us to pinpoint the most likely sources for our cases of laboratory-acquired infection.

The clinical and microbiological characteristics of enteric fever in Cambodia, 2008-2015

BACKGROUND

Enteric fever remains a major public health problem in low resource settings and antibiotic resistance is increasing. In Asia, an increasing proportion of infections is caused by Salmonella enterica serovar Paratyphi A, which for a long time was assumed to cause a milder clinical syndrome compared to Salmonella enterica serovar Typhi.

METHODOLOGY

A retrospective chart review study was conducted of 254 unique cases of blood culture confirmed enteric fever who presented at a referral adult hospital in Phnom Penh, Cambodia between 2008 and 2015. Demographic, clinical and laboratory data were collected from clinical charts and antibiotic susceptibility testing was performed. Whole genome sequence analysis was performed on a subset of 121 isolates.

RESULTS

One-hundred-and-ninety unique patients were diagnosed with Salmonella Paratyphi A and 64 with Salmonella Typhi. In the period 2008-2012, Salmonella Paratyphi A comprised 25.5% of 47 enteric fever cases compared to 86.0% of 207 cases during 2013-2015. Presenting symptoms were identical for both serovars but higher median leukocyte counts (6.8 x 109/L vs. 6.3 x 109/L; p = 0.035) and C-reactive protein (CRP) values (47.0 mg/L vs. 36 mg/L; p = 0.034) were observed for Salmonella Typhi infections. All but one of the Salmonella Typhi isolates belonged to haplotype H58 associated with multidrug resistance (MDR) (i.e. resistance to ampicillin, chloramphenicol and co-trimoxazole).;42.9% actually displayed MDR compared to none of the Salmonella Paratyphi A isolates. Decreased ciprofloxacin susceptibility (DCS) was observed in 96.9% (62/64) of Salmonella Typhi isolates versus 11.5% (21/183) of Salmonella Paratyphi A isolates (all but one from 2015). All isolates were susceptible to azithromycin and ceftriaxone.

CONCLUSIONS

In Phnom Penh, Cambodia, Salmonella Paratyphi A now causes the majority of enteric fever cases and decreased susceptibility against ciprofloxacin is increasing. Overall, Salmonella Typhi was significantly more associated with MDR and DCS compared to Salmonella Paratyphi A.

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.

Safety and immunogenicity of an attenuated Salmonella enterica serovar Paratyphi A vaccine candidate

Enteric fever caused by Salmonella enterica serovar Paratyphi A has progressively increased in recent years and became a global health issue. Currently licensed typhoid vaccines do not confer adequate cross-immunoprotection against S. Paratyphi A infection. Therefore, vaccines specifically against enteric fever caused by S. Paratyphi A are urgently needed. In the present study, an attenuated vaccine strain was constructed from S. Paratyphi A CMCC50093 by the deletions of aroC and yncD. The obtained strain SPADD01 showed reduced survival within THP-1 cells and less bacterial burden in spleens and livers of infected mice compared with the wild-type strain. The 50% lethal doses of SPADD01 and the wild-type strain were assessed using a murine infection model. The virulence of SPADD01 is approximately 40,000-fold less than that of the wild-type strain. In addition, SPADD01 showed an excellent immunogenicity in mouse model. Single intranasal inoculation elicited striking humoral and mucosal immune responses in mice and yielded effective protection against lethal challenge of the wild-type strain. A high level of cross-reactive humoral immune response against LPS of Salmonella enterica serovar Typhi was also detected in immunized mice. However, SPADD01 vaccination only conferred a low level of cross-protection against S. Typhi. Our data suggest that SPADD01 is a promising vaccine candidate against S. Paratyphi A infection and deserves further evaluation in clinical trial. To date, no study has demonstrated a good cross-protection between serovars of S. Typhi and S. Paratyphi A, suggesting that the dominant protective antigens of both serovars are likely different and need to be defined in future study.

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.

Enteric fever imported to the Czech Republic: epidemiology, clinical characteristics and antimicrobial susceptibility

The aim of this study was to describe epidemiological and clinical characteristics of imported enteric fever in Czech travellers and to determine the antimicrobial susceptibility of isolated strains. Retrospective descriptive study included adult patients treated with enteric fever at Hospital Na Bulovce during January 2004-December 2012. A case of typhoid or paratyphoid fever was defined as isolation of Salmonella Typhi or Paratyphi from blood or stool. During the study period, there have been diagnosed 19 cases of enteric fever (12 males and 7 females) with age median of 30 years; 14 cases were caused by Salmonella Typhi and 5 cases by S. Paratyphi A. The infection has been acquired in South Asia (16 patients; 84.2 %), in Africa (Egypt, Angola) in two cases (10.5 %), and in Mexico (1; 5.3 %). Symptoms included fever (all patients), diarrhoea (16 cases; 84.2 %), headache (9; 47.4 %), and abdominal pain (7; 36.8 %). Seventeen patients (89.5 %) were treated with fluoroquinolones; however, the treatment failure was observed in seven of them (41.2 %). Decreased ciprofloxacin susceptibility was detected in eight strains (66.7 %), and one strain (8.3 %) was multidrug resistant. Sequence analysis of quinolone resistance-determining regions (QRDR) of the gyrA gene revealed the presence of amino acid substitutions in all tested isolates with decreased ciprofloxacin susceptibility. Typhoid and paratyphoid fevers represent epidemiologically important diseases that may lead to potentially life-threatening complications. Major issue in the management of enteric fever represents the non-susceptibility of Salmonella strains to fluoroquinolones and other antimicrobials.

Paratyphoid fever: splicing the global analyses

The incidence of enteric fever caused by Salmonella enterica serovar Paratyphi A (S. Paratyphi A) is increasing in many parts of the world. Although there is no major outbreak of paratyphoid fever in recent years, S. Paratyphi A infection still remains a public health problem in many tropical countries. Therefore, surveillance studies play an important role in monitoring infections and the emergence of multidrug resistance, especially in endemic countries such as India, Nepal, Pakistan and China. In China, enteric fever was caused predominantly by S. Paratyphi A rather than by Salmonella enterica serovar Typhi (S. Typhi). Sometimes, S. Paratyphi A infection can evolve into a carrier state which increases the risk of transmission for travellers. Hence, paratyphoid fever is usually classified as a "travel-associated" disease. To date, diagnosis of paratyphoid fever based on the clinical presentation is not satisfactory as it resembles other febrile illnesses, and could not be distinguished from S. Typhi infection. With the availability of Whole Genome Sequencing technology, the genomes of S. Paratyphi A could be studied in-depth and more specific targets for detection will be revealed. Hence, detection of S. Paratyphi A with Polymerase Chain Reaction (PCR) method appears to be a more reliable approach compared to the Widal test. On the other hand, due to increasing incidence of S. Paratyphi A infections worldwide, the need to produce a paratyphoid vaccine is essential and urgent. Hence various vaccine projects that involve clinical trials have been carried out. Overall, this review provides the insights of S. Paratyphi A, including the bacteriology, epidemiology, management and antibiotic susceptibility, diagnoses and vaccine development.

Antimicrobial resistance in Salmonella enterica serovar typhi and paratyphi in South Asia-current status, issues and prospects

The human race owes a debt of gratitude to antimicrobial agents, penicillin and its successors that have saved people from tremendous pain and suffering in the last several decades. Unfortunately, this consideration is no more true, as millions of people are prone to the challenging threat of emergence of antimicrobial resistance worldwide and the menace is more distressing in developing countries. Comparable with other bacterial species, Salmonella enterica serovar Typhi (S. typhi) and Paratyphi (S. paratyphi) have been evolving multidrug resistance (MDR) against a wide array of antibiotics, including chloramphenicol, ampicillin and co-trimoxazole, and globally affecting 21 million people with 220,000 deaths each year. S. typhi and S. paratyphi infections are also endemic in South Asia and a series of antibiotics used to treat these infections, have been losing efficacy against enteric fever. Currently, quinolones are regarded as a choice to treat MDR Salmonella in these regions. Travel-related cases of enteric fever, especially from South Asian countries are the harbinger of the magnitude of MDR Salmonella in that region. Conclusively, the MDR will continue to grow and the available antimicrobial agents would become obsolete. Therefore, a radical and aggressive approach in terms of rational use of antibiotics during treating infections is essentially needed.

Near-fatal myocarditis complicating typhoid fever in a traveler returning from Nepal

We report a 27-year-old traveler who returned from Nepal suffering from typhoid fever. His disease was complicated by life-threatening myocarditis and ventricular fibrillation, a rare manifestation in travelers.

Cases of typhoid fever in Copenhagen region: a retrospective study of presentation and relapse

Background

Typhoid fever is a systemic illness which in high-income countries mainly affects travellers. The incidence is particularly high on the Indian subcontinent. Travellers who visit friends and relatives (VFR) have been shown to have a different risk profile than others. We wished to identify main characteristics for travellers infected with S. Typhi considering both clinical and laboratory findings in order to provide for faster and better diagnostics in the future. The outcome of treatment, especially concerning relapse, was evaluated as well.

Methods

Retrospectively collected data from 19 adult cases of typhoid fever over a 5-year period at the Department of Infectious Diseases, Copenhagen University Hospital, Hvidovre Denmark.

Results

The patients were young adults, presenting with symptoms within a month after travelling. 84% were returned from travelling in the Indian subcontinent. 17 out of 19 patients were VFR-travellers. The main symptoms were fever (100%), gastrointestinal symptoms (84%), headache (58%) and dry cough (26%). Laboratory findings showed elevated C-reactive protein (CRP) and lactate dehydrogenase (LDH) in all cases and elevated alanine transaminase (ALAT) in 47% of cases. In primary cases 4 isolates were fully susceptible to ciprofloxacin, the remaining were intermediate susceptible. Relapse occurred in 37% of the cases and only in cases where the patient was infected by a strain with intermediate susceptibility.

Conclusions

Better pre-travel counselling should be given to VFR-travellers. The main symptoms and laboratory findings confirm previous findings. The relapse rate was unexpected high and could be correlated to ciprofloxacin-resistance.

Small bowel perforation secondary to enteric Salmonella paratyphi A infection

A patient of Pakistani-origin was admitted to Bradford Royal Infirmary, UK, following a 3-week history of cough, headache and general malaise. He had recently spent 10 weeks in Pakistan and on return had been diagnosed in the community with Swine flu. He developed abdominal pain and diarrhoea in the week prior to admission, and presented to hospital with fever, tachycardia and raised inflammatory markers. He deteriorated rapidly, developing signs of peritonism and Salmonella paratyphi A was grown from blood cultures. CT demonstrated a small volume of free fluid within the abdomen and the patient underwent laparotomy. A small bowel perforation was resected and a side to side anastomosis fashioned. Treatment with intravenous antibiotics was completed and the patient was discharged 9 days postoperatively.

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.

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.

Un abcès du sein à Salmonella typhi et revue de la littérature

We report the case of a 54-year-old woman who presented with breast abscess, which appeared through a common alimentary toxi-infection with Salmonella Typhi, infection, which implied twelve patients having attended the same restaurant. With around hundred native cases a year in France, typhoid fever is not a very frequent toxi-infection. Among the known extra-intestinal manifestations of Salmonella infections, the breast abscess remains rare and the literature revealed less than ten published cases, including some revealed the disease. In our observation, the imputability of S. Typhi was retained based on the chronology of the clinical signs, specific treatments, and the successful outcome under antibiotherapy, in spite of the negativity of the breast abscess bacteriological samples. We also analyze rare cases of breast abscess due to S. Typhi found in the literature.

Salmonella paratyphi A enteric fever mimicking viral meningitis

Enteric fevers are caused by invasive strains of Salmonella. Classic enteric fever is caused by S. typhi and usually less severe enteric fevers are caused by S. paratyphi A, B, or C. We present a case of S. paratyphi A enteric fever aseptic meningitis. Headache was so prominent in the case presented that a lumbar puncture was performed to rule out meningitis. Rose spots were not apparent in this dark-skinned patient. Our patient did not have increased serum transaminases and did not have leukopenia, which are common findings in enteric fever. The absence of these findings and the relative bradycardia may be explained by the antimicrobial therapy the patient received before admission. After ruling out malaria, clinicians should suspect enteric fever in patients recently returning from endemic areas, in patients presenting with acute fevers without localizing signs.

Spectrum of disease and relation to place of exposure among ill returned travelers

BACKGROUND

Approximately 8 percent of travelers to the developing world require medical care during or after travel. Current understanding of morbidity profiles among ill returned travelers is based on limited data from the 1980s.

METHODS

Thirty GeoSentinel sites, which are specialized travel or tropical-medicine clinics on six continents, contributed clinician-based sentinel surveillance data for 17,353 ill returned travelers. We compared the frequency of occurrence of each diagnosis among travelers returning from six developing regions of the world.

RESULTS

Significant regional differences in proportionate morbidity were detected in 16 of 21 broad syndromic categories. Among travelers presenting to GeoSentinel sites, systemic febrile illness without localizing findings occurred disproportionately among those returning from sub-Saharan Africa or Southeast Asia, acute diarrhea among those returning from south central Asia, and dermatologic problems among those returning from the Caribbean or Central or South America. With respect to specific diagnoses, malaria was one of the three most frequent causes of systemic febrile illness among travelers from every region, although travelers from every region except sub-Saharan Africa and Central America had confirmed or probable dengue more frequently than malaria. Among travelers returning from sub-Saharan Africa, rickettsial infection, primarily tick-borne spotted fever, occurred more frequently than typhoid or dengue. Travelers from all regions except Southeast Asia presented with parasite-induced diarrhea more often than with bacterial diarrhea.

CONCLUSIONS

When patients present to specialized clinics after travel to the developing world, travel destinations are associated with the probability of the diagnosis of certain diseases. Diagnostic approaches and empiric therapies can be guided by these destination-specific differences.

[Salmonellosis in a maternity-children's hospital in Barcelona over a 10-year period (1992-2001)]

BACKGROUND

We performed a retrospective study of Salmonella spp. strains, as well as of serotypes and resistance to antimicrobial agents that could be useful in salmonellosis requiring antibiotic treatment.

MATERIAL AND METHODS

All Salmonella strains isolated in a maternity-children's hospital in Barcelona (Spain) during a 10-year period (1992-2001) were serotyped. The susceptibility of the strains isolated from 1994 to ampicillin, amoxicillin-clavulanic acid, chloramphenicol, trimethoprim-sulfamethoxazole and cefotaxime was analyzed. Ciprofloxacin substituted chloramphenicol in the analysis of strains isolated during the last 2 years of the study period.

RESULTS AND DISCUSSION

A total of 860 isolates from 31 distinct serotypes were analyzed. The most frequent serotypes were S. enteritidis (48.7 %), S. typhimurium (33.4 %), S. virchow (5 %), S. hadar (1.8 %) and S. typhi (1.5 %). We found a high percentage of strains resistant to ampicillin (44.6 % in 2001) and chloramphenicol (28.7 % in 1999) and a lower percentage of strains resistant to amoxicillin-clavulanic acid and trimethoprim-sulfamethoxazole (2.2 % and 6.5 % respectively, among the strains isolated in 2001). Only one cefotaxime-resistant strain was found, and all isolates were susceptible to ciprofloxacin. Our results provide useful epidemiological information for the control of these infections, which remain a serious public health problem all over the world.

Typhoid and paratyphoid fever in travellers

Enteric fever--a more inclusive term for typhoid fever and paratyphoid fever--is a systemic infection caused by Salmonella enterica, including S enterica serotype Typhi (S typhi) and serotype Paratyphi (S paratyphi). In developed countries there have been two major changes in the pattern of the disease: a marked decline in its incidence and its characterisation as a predominantly travel-associated disease. The risk to travellers appears to vary by geographic region visited, with travel to the Indian subcontinent accounting for the greatest travel risk. Although the most common cause of enteric fever is S typhi, the incidence of disease caused by S paratyphi among travellers may be more important, since the available vaccines only protect against S typhi. Descriptions of the clinical presentation in travellers are scarce but severe complications and death are rare, probably due to rapid access to readily available medical care. Drug resistance reflects the situation in endemic countries, and shows a steady increase in multidrug-resistance patterns. Currently, the recommendation for first-line therapy is ceftriaxone and, where isolates have been found to be quinolone sensitive, fluoroquinolones can still be given. Preventive measures are educating travellers about hygiene precautions and vaccination. With an increase in multidrug-resistant strains, a more effective vaccine for S typhi and S paratyphi is urgently needed.

Enteric (typhoid) fever in travelers

The incidence of enteric (typhoid) fever in travelers is estimated to be approximately 3-30 cases per 100,000 travelers to developing countries. Recently, it is become clear that travelers who are visiting friends and relatives, especially travelers to the Indian subcontinent, seem to be the most vulnerable to enteric fever and require special attention for prevention. Recent concerns are the increasing incidence of paratyphoid fever in Asia, which is not covered by available typhoid vaccines, and the emergence of infections caused by antibiotic-resistant strains (including strains resistant to fluoroquinolones). Typhoid vaccination is recommended for most travelers to moderate- to high-risk countries. Because of the nonspecific clinical presentation of enteric fever, a high index of suspicion is important in febrile travelers who have traveled to areas of endemicity.

Enteric fever in Israeli travelers: a nationwide study

BACKGROUND

Enteric fever (EF) has become a travel-related disease in industrialized countries. The possible effects of vaccination on typhoid epidemiology in travelers are unknown. We compared the incidence and clinical and microbiologic findings in travelers returning with EF, according to pretravel vaccination status and vaccine type.

METHODS

We performed a nationwide descriptive analysis of EF incidence in Israeli travelers; EF is a notified disease in Israel. Data from 1995 through 2003 were evaluated; all cases of EF acquired during recent travel (6 wk) were included. From 1995 to 1999, the Ty21a oral vaccine was used exclusively in Israel. It was replaced with the Vi vaccine from 2000 to 2003. Patients with pretravel typhoid vaccination were compared with unvaccinated patients, and according to vaccine type.

RESULTS

Seventy-eight cases met our criteria. The causative agents were Salmonella typhi in 79.5% and Salmonella paratyphi A in 20.5%; 74.4% were acquired by travelers to the Indian Subcontinent. S. paratyphi A accounted for 10.5% of cases among Ty21a vaccinees as compared with 47.4% among Vi vaccinees (p = .02). For the Indian Subcontinent, the general attack rate of S. typhi and S. paratyphi A during the period of vaccination with Ty21a was 2.37 in 10,000 and 0.26 in 10,000 travelers, respectively, whereas during the period of vaccination with Vi, the attack rate was 1.40 in 10,000 and 0.79 in 10,000. There were no deaths; however, more complications and relapses occurred in the S. paratyphi A group.

CONCLUSIONS

Among Israeli travelers S. typhi infection is declining whereas S. paratyphi A is increasing, with most cases occurring in vaccinated travelers. Prior typhoid vaccination did not modify the course of the disease. S. paratyphi A infection in travelers is not milder than S. typhi infection. Although this is not a prospective, controlled, randomized trial, it appears that the Ty21a vaccine may be less effective for S. typhi but may offer some protection against S. paratyphi A. Sequential vaccination with the available oral and Vi vaccine may merit consideration. A more effective vaccine for S. typhi and S. paratyphi A is urgently needed.

Risk of travel-associated typhoid and paratyphoid fevers in various regions

BACKGROUND

Although enteric fever (typhoid and paratyphoid fevers) is a major global public health problem, comparable data on the risks of contracting travel-associated enteric fever in various regions of the world are scarce.

METHODS

From the Swedish database on notifiable communicable diseases, we retrieved all case records from 1997 to 2003 on typhoid and paratyphoid fevers. The data set was compared with data on travel patterns obtained from a comprehensive travel database with information from interviews with more than 16,000 Swedish residents with recent overnight travel outside Sweden.

RESULTS

The overall risk of being notified with enteric fever after travel was 0.42 in 100,000 travelers. The highest risk for typhoid fever was seen in travelers from India and neighboring countries (41.7 in 100,000), the Middle East (5.91 in 100,000), and Central Africa (3.33 in 100,000), whereas the risk was comparatively low in East Asia (0.24 in 100,000). Almost the same risk areas stood out for paratyphoid fever: India and neighbors (37.5 in 100,000), the Middle East (3.64 in 100,000), and East Africa (3.33 in 100,000). The epidemiology of paratyphoid fever was considerably affected by a large outbreak of paratyphoid B in a Turkish tourist resort in 1999. The youngest children were at highest risk for typhoid fever (odds ratio 44.2), whereas youths ages 7 to 18 years were at highest risk for paratyphoid fever (odds ratio 9.7).

CONCLUSIONS

Detailed risk data for enteric fever after travel could form the basis for travel advice. Vaccination against typhoid fever should always be considered for travelers to the Indian subcontinent, the Middle East, and Africa but should not routinely be given to travelers to the Malay Peninsula.

Practice guidelines for evaluation of Fever in returning travelers and migrants

BACKGROUND

Fever upon return from tropical or subtropical regions can be caused by diseases that are rapidly fatal if left untreated. The differential diagnosis is wide. Physicians often lack the necessary knowledge to appropriately take care of such patients.

OBJECTIVE

To develop practice guidelines for the initial evaluation of patients presenting with fever upon return from a tropical or subtropical country in order to reduce delays and potential fatal outcomes and to improve knowledge of physicians.

TARGET AUDIENCE

Medical personnel, usually physicians, who see the returning patients, primarily in an ambulatory setting or in an emergency department of a hospital and specialists in internal medicine, infectious diseases, and travel medicine.

METHOD

A systematic review of the literature--mainly extracted from the National Library of Medicine database--was performed between May 2000 and April 2001, using the keywords fever and/or travel and/or migrant and/or guidelines. Eventually, 250 articles were reviewed. The relevant elements of evidence were used in combination with expert knowledge to construct an algorithm with arborescence flagging the level of specialization required to deal with each situation. The proposed diagnoses and treatment plans are restricted to tropical or subtropical diseases (nonautochthonous diseases). The decision chart is accompanied with a detailed document that provides for each level of the tree the degree of evidence and the grade of recommendation as well as the key points of debate. PARTICIPANTS AND CONSENSUS PROCESS: Besides the 4 authors (2 specialists in travel/tropical medicine, 1 clinical epidemiologist, and 1 resident physician), a panel of 11 European physicians with different levels of expertise on travel medicine reviewed the guidelines. Thereafter, each point of the proposed recommendations was discussed with 15 experts in travel/tropical medicine from various continents. A final version was produced and submitted for evaluation to all participants.

CONCLUSION

Although the quality of evidence was limited by the paucity of clinical studies, these guidelines established with the support of a large and highly experienced panel should help physicians to deal with patients coming back from the Tropics with fever.

Vaccination priorities

Selection of immunizations should be based on requirements and on risk of infection. According to the International Health Regulations, many countries require yellow fever vaccination and proof thereof as the International Certificate of vaccination. Additionally selected countries require proof of vaccination against cholera and meningococcal disease. A consultation for travel health advice is always an opportunity to ascertain that routine immunizations have been performed. Recommended immunizations often are more important for traveller's health than the required or routine ones. The most frequent vaccine preventable infection in non-immune travellers to developing countries is hepatitis A with an average incidence rate of 0.3% per month; in high risk backpackers or foreign-aid-volunteers this rate is 2.0%. Many immunizations are recommended for special risk groups only: there is a growing tendency in many countries to immunize all young travellers to developing countries against hepatitis B, as it is uncertain who will voluntarily or involuntarily get exposed. The attack rate of influenza in intercontinental travel is estimated to be 1%. Immunity against poliomyelitis remains essential for travel to Africa and parts of Asia. Many of the 0.2-0.4% who experience an animal bite are at risk of rabies. Typhoid fever is diagnosed with an incidence rate of 0.03% per month among travellers to the Indian subcontinent, North and West Africa (except Tunisia), and Peru, elsewhere this rate is 10-fold lower. Meningococcal disease, Japanese encephalitis, cholera and tuberculosis have been reported in travellers, but these infections are rare in this population. Although no travel health vaccine is cost beneficial, most professionals will offer protection against the frequent risks, while most would find it ridiculous to use all available vaccines in every traveller. It is essentially an arbitrary decision made on the risk level one wishes to recommend protection--but the priorities need to be set correctly.

Evaluation of fever in the returned traveler

The primary care practitioner often is the first clinician sought out by a returning traveler, and it is important that he or she be alert to the possibility of exotic illness while remembering the more mundane causes of fever. Malaria remains one of the most serious diagnoses in a febrile traveler and should be looked for repeatedly. Other diagnoses may be suggested by exposure history and patterns of laboratory findings. A directed diagnostic workup, rational empiric therapy, and appropriate consultation are the tools with which the primary care provider successfully can manage the challenging dilemma posed by the returning traveler with fever.