Multidrug resistant typhoid fever outbreak in Ercek Village-Van, Eastern Anatolia, Turkey: clinical profile, sensitivity patterns and response to antimicrobials

Typhoid Outbreaks, 1989-2018: Implications for Prevention and Control

Typhoid fever remains an important public health problem in low- and middle-income countries, with large outbreaks reported from Africa and Asia. Although the WHO recommends typhoid vaccination for control of confirmed outbreaks, there are limited data on the epidemiologic characteristics of outbreaks to inform vaccine use in outbreak settings. We conducted a literature review for typhoid outbreaks published since 1990. We found 47 publications describing 45,215 cases in outbreaks occurring in 25 countries from 1989 through 2018. Outbreak characteristics varied considerably by WHO region, with median outbreak size ranging from 12 to 1,101 cases, median duration from 23 to 140 days, and median case fatality ratio from 0% to 1%. The largest number of outbreaks occurred in WHO Southeast Asia, 13 (28%), and African regions, 12 (26%). Among 43 outbreaks reporting a mode of disease transmission, 24 (56%) were waterborne, 17 (40%) were foodborne, and two (5%) were by direct contact transmission. Among the 34 outbreaks with antimicrobial resistance data, 11 (32%) reported Typhi non-susceptible to ciprofloxacin, 16 (47%) reported multidrug-resistant (MDR) strains, and one reported extensively drug-resistant strains. Our review showed a longer median duration of outbreaks caused by MDR strains (148 days versus 34 days for susceptible strains), although this difference was not statistically significant. Control strategies focused on water, sanitation, and food safety, with vaccine use described in only six (13%) outbreaks. As typhoid conjugate vaccines become more widely used, their potential role and impact in outbreak control warrant further evaluation.

Multidrug-resistant typhoid fever with neurologic findings on the Malawi-Mozambique border

BACKGROUND

Salmonella enterica serovar Typhi causes an estimated 22 million cases of typhoid fever and 216 000 deaths annually worldwide. We investigated an outbreak of unexplained febrile illnesses with neurologic findings, determined to be typhoid fever, along the Malawi-Mozambique border.

METHODS

The investigation included active surveillance, interviews, examinations of ill and convalescent persons, medical chart reviews, and laboratory testing. Classification as a suspected case required fever and ≥1 other finding (eg, headache or abdominal pain); a probable case required fever and a positive rapid immunoglobulin M antibody test for typhoid (TUBEX TF); a confirmed case required isolation of Salmonella Typhi from blood or stool. Isolates underwent antimicrobial susceptibility testing and subtyping by pulsed-field gel electrophoresis (PFGE).

RESULTS

We identified 303 cases from 18 villages with onset during March-November 2009; 214 were suspected, 43 were probable, and 46 were confirmed cases. Forty patients presented with focal neurologic abnormalities, including a constellation of upper motor neuron signs (n = 19), ataxia (n = 22), and parkinsonism (n = 8). Eleven patients died. All 42 isolates tested were resistant to ampicillin, chloramphenicol, and trimethoprim-sulfamethoxazole; 4 were also resistant to nalidixic acid. Thirty-five of 42 isolates were indistinguishable by PFGE.

CONCLUSIONS

The unusual neurologic manifestations posed a diagnostic challenge that was resolved through rapid typhoid antibody testing in the field and subsequent blood culture confirmation in the Malawi national reference laboratory. Extending laboratory diagnostic capacity, including blood culture, to populations at risk for typhoid fever in Africa will improve outbreak detection, response, and clinical treatment.

Epidemiological characteristics and molecular typing of Salmonella enterica serovar Typhi during a waterborne outbreak in Eastern Anatolia

In this study, we aimed to study the molecular and epidemiological characteristics of Salmonella enterica serovar Typhi (S. Typhi) outbreak in Eastern Anatolia. Six hundred and thirty-seven patients from the same county with clinical diagnosis of typhoid fever were investigated with conventional methods from stool, urine and blood specimens. Antibiotic susceptibility tests and identifications were performed for positive specimens. Clonal relationships between the isolates were investigated using pulsed field gel electrophoresis (PFGE) method. A questionnaire was completed for the water consumption habits of patients. Of 91 culture positive specimens, 76 were blood, 13 were stool and 2 were urine. The isolates were resistant to ampicillin, ampicillin/sulbactam, chloramphenicol, cefuroxime, amikacin, gentamicin and trimethoprim-sulfamethoxazole. Although there was a single band difference in some isolates, PFGE results indicated that this was an outbreak caused by single strain according to the Tenover criteria. This outbreak thought to be associated with the consumption of tap water contaminated with sewage represents a breakdown of the basic public health and civil engineering infrastructure. Appropriate public health measures should be taken in order to avoid such outbreaks in the future.

Analysis of characteristics of paratyphoid A in 157 Chinese inpatients between 1998 and 2009

The objectives of this study were to understand the epidemic rules, clinical characteristics, and drug resistance of paratyphoid A by analyzing 157 cases in the Wenzhou area of China during a 12-year period. The subjects included in the present study were patients with paratyphoid A who were admitted to the First Affiliated Hospital of Wenzhou Medical College (Wenzhou, ZJ, China) between 1998 and 2009. The disease mainly occurred in persons aged 20 to 50 years. The peak incidence was between 2001 and 2003 (n = 85). Paratyphoid A was more likely to occur in winter and spring in this area. In many cases (33.8%), the condition was complicated by underlying diseases. The length of hospital stay was relatively long, averaging 17.68 days. The white blood cell (WBC) count was 2-8 × 10(9)/L in 88.5% of cases. Eosinophils disappeared in 51.7% of cases. The erythrocyte sedimentation rate (ESR) was not significant and lower than 60 mm/h in 88.5% of cases. Alanine aminotransferase (ALT) was ≤3-fold greater than the normal value in 84.3% of cases. The Widal test was positive in only 7.7% of our cases. The sensitivity of many antibiotics was over 90%. Paratyphoid A in the Wenzhou area has unique epidemic rules, clinical characteristics, and drug resistance. The results of our retrospective analysis are instructive for the early diagnosis and rational treatment of paratyphoid A.