Epidemiological characteristics and molecular typing of typhoid and paratyphoid in China, 2009-2013 / 中华流行病学杂志

Objective: To understand the epidemiological and molecular characteristics of typhoid and paratyphoid in China from 2009 to 2013, and provide evidence for the prevention and control of typhoid and paratyphoid, the development and improvement of surveillance strategies. Methods: Epidemiological analysis was conducted on the incidence data of typhoid and paratyphoid, and related public health emergencies in China during 2009-2013. Pathogen isolation and culture, serologic test were conducted for the typhoid and paratyphoid cases from 13 national surveillance sites. The isolates were subjected to antimicrobial susceptibility testing. Pulsed-field gel electrophoresis (PFGE) was performed for the molecular typing of these isolates. Results: The average incidence of typhoid and paratyphoid in China during this period was 1.03/100 000. The reported case number and incidence decreased with year. The provinces reporting high case numbers were Yunnan, Guizhou, Guangxi, Hunan, Zhejiang, Guangdong and Xinjiang. The incidence of age group 0-4 years was highest. The proportion of farmers and children outside child care settings showed an increasing tendency over time. The annual incidence peak was during July-August. Twenty five outbreaks occurred during 2009-2013. The results of pathogen isolation and culture showed that the positive rate was 3.00% (940/31 322), among the positive isolates, the proportion of Salmonella paratyphi A accounted for higher proportion (68.19%, 641/940) compared with Salmonella typhi (31.60%, 297/940). The drug resistances of Salmonella typhi and Salmonella paratyphi varied, but their resistances to nalidixic acid were highest (50.22% and 85.33%) respectively. A certain amount of Salmonella typhi isolates showed the resistance to the 3rd generation cephalosporins. PFGE analysis showed divergent patterns of Salmonella typhi compared with limited patterns of Salmonella paratyphi A. Conclusion: The epidemic level of typhoid and paratyphoid in China was relatively low, but the outbreak occurred occasionally. It is necessary to enhance the laboratory-based surveillance, particularly the capability of etiological diagnosis, outbreak investigation, response and antibiotic resistance monitoring, and conduct risk factor investigation in provinces with high incidences in recent years.

Occurrence & antibiogram of Salmonella Typhi & S. Paratyphi A isolated from Rourkela, Orissa.

Background & objectives: Almost round-the-year occurrence of Salmonella Typhi and Salmonella Paratyphi A has been noticed in Rourkela since last 13 and five years respectively. The incidence of infection along with the antibiogram of these two serotypes in this area were carried out. Methods: The study was carried out at Ispat General Hospital, Rourkela, India, between January 2005 and December 2008 with 5340 blood samples collected from patients with suspected enteric fever and pyrexia of unknown origin. Isolation, identification and antibiogram of the causative organisms were performed according to standard bacteriological procedures. Results: A total of 298 Salmonella isolates showed an overall per cent positivity of 5.58. Multidrug resistance was found in 11.96 per cent and 15.62 per cent isolates of S. Typhi and S. Paratyphi A respectively. Less than 2 per cent isolates of Salmonella showed resistance to ciprofloxacin. A resistance of 3.0 to 6.25 per cent against third generation cephalosporins was observed among the salmonella isolates. Interpretation & conclusion: A round-the-year occurrence of Salmonella spp. in Rourkela might have been due to the presence of a considerable number of carriers in the locality, poor sanitation in nearby slum areas, and inadequate and contaminated community water supply at times. Higher degree of susceptibility among S. Typhi isolates against various antibiotics was encouraging, but increasing trend of resistance observed among S. Paratyphi A isolates was a matter of concern.

Isolation of Salmonella paratyphi A from renal abscess.

Intrarenal abscesses remain a significant cause of morbidity and mortality as well as a diagnostic dilemma because a plethora of microorganisms can cause this condition. A definitive diagnosis is made by demonstrating the organisms from the aspirate and the success or failure of therapy depends upon the antimicrobial sensitivity pattern. Enteric fever is a multisystem disorder caused by invasive strains of salmonella. Salmonellosis continues to be a major public health problem, especially in developing countries. Classic enteric fever is caused by S. typhi and usually less severe enteric fevers are caused by S. paratyphi A, B, or C. However, at times S. paratyphi is capable of causing serious and often life-threatening infections like infective endocarditis, pericarditis, empyma, sino-venous thrombosis, osteomyelitis, meningitis, bone marrow infiltration, hepatitis and pancreatitis. There are anecdotal case reports in world literature of abscesses being caused by this organism. Renal involvement like bacteriuria, nephrotic syndrome and acute renal failure have been reported due to S. parayphi A. S. paratyphi A has never been implicated in renal abscess, we report one such case that was managed successfully with medical therapy.

Enteric fever in Mumbai--clinical profile, sensitivity patterns and response to antimicrobials.

AIMS: Enteric fever is endemic in Mumbai and its diagnosis poses several problems. Our main aim was to study the clinical profile, haematological features of culture proven typhoid cases, the antimicrobial susceptibility pattern of the isolates and the time to defervescence with the treatment received. MATERIAL AND METHODS: This was a retospective chart review of all cases of culture proven enteric fever carried out at a tertiary care private hospital in Mumbai over the period January 2003 to September 2005. RESULTS: Culture positivity in our study was 52.6%. Sixty one percent of the isolates were Salmonella typhi while 39% were Salmonella paratyphi A. An absolute eosinopenia was seen in 76.9% of the patients. Before being admitted to the hospital, 46.2% received antibiotics. The mean time to defervescence in patients who received prior antibiotics was 4.5 days while that in those who did not receive prior antibiotics was 5.1 days. CONCLUSIONS: A high culture positivity despite prior or ongoing antibiotic treatment was seen. Absolute eosinophil count of 0% could be an important marker of typhoid. High prevalence of nalidixic acid resistance, a marker of resistance to fluoroquinolones was observed. Combination treatment was not found to be superior to treatment with a single antibiotic.

Evaluation of Widal test in diagnosis of typhoid fever among patients in Aden, Yemen

Salmonella typhi is strictly human pathogen and has no animal reservoir. The laboratory diagnosis of typhoid fever depends upon either clinical investigation or the detection of titers of agglutination of serum antibodies [Widal test]. 216 Yemeni patients with suspected typhoid fever, were investigated with Widal test, slide agglutination test and stool culture. The Widal test showed different results which then compared with conventional broth and solid culture of, MacConkey [MA], Salmonella-Shigella agar [SSA], Bismuth Sulfite Agar [BSA], Xylose Lysine Deoxycholate [XLD] and Kligller Iron Agar [KIA]. The presence of S. typhi was in 4 patients [1.85%], whereas S. paratyphi AB was detected in 24 patients [11.11%]. The stool cultures and biochemical tests the existence of S. typhi the causative agent of typhoid fever. Then the typhoid fever was further confirmed by the API 20E system

Vertical transmission of Salmonella paratyphi A.

Neonatal enteric fever is a rare but life-threatening illness. Patients may present with varying severity, Salmonella enterica serotype Typhi causing more severe illness than Salmonella enterica serotype Paratyphi A. Salmonella enterica serotype Paratyphi A is considered to cause milder infection with fewer complications. We report a rare case of vertical transmission of Salmonella enterica serotype Paratyphi A with severe complications and high mortality. Even though there are case reports of vertical transmission of Salmonella enterica serotype Typhi, to our knowledge, this is the first case report of vertical transmission of Salmonella enterica serotype ParatyphiA. The role of blood culture in accurate diagnosis and treatment is also discussed.

Paratyphoid sepsis.

A large for gestational age male baby was born to a healthy young primigravida, on L-thyroxime, at 40 weeks by caesarean delivery in a tertiary care hospital. The baby had episodes of hypoglycemia during his immediate four postnatal days in the nursery that were successfully managed with intravenous glucose administration. The baby became unwell on day 5 and had a positive sepsis-screening test. Blood culture revealed a multidrug susceptible S. Paratyphi A strain, which he probably acquired on the first or second postnatal day from the contaminated expressed breast milk or the formula feed.

Development of an ultra rapid and simple multiplex polymerase chain reaction technique for detection of salmonella typhi

To make a rapid and definite diagnosis of Salmonella enteritis, using an ultra rapid multiplex polymerase chain reaction [PCR] detection method for major Salmonella serotypes, such as Salmonella typhi, Salmonella Typhimurium and Salmonella Havana. We performed this study at the Research Center of Molecular Biology, Institute of Military Medicine, Bagyatallah University of Medical Sciences, Iran from June 2004 to July 2005. The PCR primers for tyv [rfbE], prt [rfbS] and invA genes were designed and used for the rapid identification of Salmonella enterica serovars Typhi and Paratyphi A with multiplex PCR. By using simple DNA extraction method in 10 minutes, rapid PCR cycles with total cycle times of 35 minutes and rapid electrophoresis procedure with simple and very cheap buffer used in 200 to 300 volts for 15 minutes to separate the PCR products. The results showed that all reference and clinical isolates of Salmonella serovars Typhi and Paratyphi were accurately identified by this assay. Specificity analysis revealed no cross-reaction with other Enterobacterial strains. The sensitivity of the PCR and the multiplex PCR was 1-10 cells. The total time of Multiplex PCR from sample preparation to final result is 45-50 minutes. These data indicate that the specificity and sensitivity of the PCR and the multiplex PCR make them potentially valuable tools for diagnosis of Salmonella typhi bacteria and that they may be used for the identification of Salmonella enteritidis responsible for sporadic enteritis cases

Pleural effusion in complicated Salmonella paratyphi A infection.

Enteric fever can present with unusual manifestations. We observed a rare case of Salmonella paratyphi A infection in which multiple organs were involved and the organism was isolated from pleural fluid and blood. In the present era of antimicrobial drug resistance, awareness about such atypical presentations is essential to initiate a prompt treatment.

Isolation of salmonella paratyphi a from a patient with nephrolithiases

We describe a case of Salmonella paratyphi A isolated from urine of a 37-year-old Saudi patient who is a known case of nephrolithiasis and hydronephrosis with frequent admission for management of renal stones. History of enteric fever was not documented and urinary schistosomiasis in such a patient from endemic area is a strong possibility. Relevant literature was discussed

Antimicrobial susceptibility, phage typing and plasmid profile of salmonella enterica serotype paratyphi A strains isolated in Kuwait

To determine the antimicrobial susceptibility, phage type and plasmid profile pattern of Salmonella enterica serotype paratyphi A strains isolated in Kuwait. Material and From January 1995 to December 1999, 106 strains of S. enterica serotype paratyphi A isolated from an equal number of cases of enteric fever, attending the Infectious Disease and Mubarak Al-Kabeer Hospitals in Kuwait were investigated. The isolates were tested for antimicrobial susceptibility to 8 commonly used antimicrobial agents. Their phage type and plasmid profile patterns were determined using an international set of phages and Qiagen plasmid mini kit, respectively. All of the isolates were susceptible to ciprofloxacin, cefuroxime, ceftazidime, piperacillin and co-trimoxazole. One hundred isolates were susceptible to ampicillin, 99 to chloramphenicol and 98 to tetracycline. None of the isolates was multidrug resistant. Sixty-six% of the isolates were phage type I, 27.4% phage type II and 6.6% were untypable. All phage type I and untypable strains had 3 plasmids of 2.2, 5 and 20 kb, whereas phage type II strains had only 1 plasmid of 20 kb. The findings indicate that while all of the isolates of the S. enterica serotype paratyphi A were susceptible to 4 of the drugs tested, some were resistant to ampicillin, chloramphenicol or tetracycline, thereby indicating the need for continued surveillance and monitoring of antimicrobial susceptibility of these isolates

Hepatic abscess complicating paratyphoid infection.

Salmonellosis is ubiquitous and is a world-wide public health concern. Liver abscesses are occasionally reported in Salmonella typhi infections, they are a very rare complication of Salmonella paratyphi infections. A 28 year old male patient without any prior medical history presented with fever, abdominal pain and a tender hepatomegaly. The imaging studies revealed multiple liver abscesses and an ultrasound (US) guided aspiration of the abscess yielded heavy growth of Salmonella paratyphi A. He was treated successfully by percutaneous drainage of the abscesses and appropriate antibiotics.

Endocarditis and pericarditis caused by Salmonella paratyphi A: two case reports and review of the literature.

We report on two children with paratyphoid fever and rare cardiac complications (endocarditis and pericarditis) during an outbreak of Salmonella paratyphi A infection in Bangkok, Thailand, in 1996. Both of the patients had underlying congenital heart disease. Two cases in the literatures of endocarditis and five cases of pericarditis caused by Salmonella paratyphi were reviewed. These rare cardiac complications should be considered among persons who reside in an endemic area of enteric fever or during disease outbreaks, especially in children with underlying heart diseases.

Pancreatitis in enteric fever.

Pancreatitis in enteric fever is rare. We report two patients with enteric fever, one due to Salmonella typhi infection and other due to S. paratyphi, who on investigation were found to have pancreatitis. Both patients recovered uneventfully.

An unusual paratyphoid fever.

Salmonella typhi is known to produce acalculous cholecystitis and related gall bladder perforation. Following is a documentation of a patient of sub-phrenic abscess and gall bladder perforation which was possibly a result of Salmonella paratyphi A.

Splenic abscess--case report and review of literature.

Isolated splenic abscess is a rarity and remains a diagnostic dilemma. The presentation is nonspecific and diagnosis is often delayed. We present a case which had roentgenographic signs suggestive of splenic suppuration at admission. Of particular interest was the isolation of Salmonella paratyphi in this patient. Antibiotic therapy alone is insufficient and splenectomy remains the treatment of choice. The literature on splenic abscess is briefly reviewed.