Invasive Salmonellosis among Children Admitted to a Rural Tanzanian Hospital and a Comparison with Previous Studies

Abstract

BackgroundThe importance of invasive salmonellosis in African children is well recognized but there is inadequate information on these infections. We conducted a fever surveillance study in a Tanzanian rural hospital to estimate the case fraction of invasive salmonellosis among pediatric admissions, examine associations with common co-morbidities and describe its clinical features. We compared our main findings with those from previous studies among children in sub-Saharan Africa.Methodology/Principal FindingsFrom 1 March 2008 to 28 Feb 2009, 1,502 children were enrolled into the study. We collected clinical information and blood for point of care tests, culture, and diagnosis of malaria and HIV. We analyzed the clinical features on admission and outcome by laboratory-confirmed diagnosis. Pathogenic bacteria were isolated from the blood of 156 (10%) children, of which 14 (9%) were S. typhi, 45 (29%) were NTS and 97 (62%) were other pathogenic bacteria. Invasive salmonellosis accounted for 59/156 (38%) bacteremic children. Children with typhoid fever were significantly older and presented with a longer duration of fever. NTS infections were significantly associated with prior antimalarial treatment, malarial complications and with a high risk for death.Conclusions/SignificanceInvasive salmonellosis, particularly NTS infection, is an important cause of febrile disease among hospitalized children in our rural Tanzanian setting. Previous studies showed considerable variation in the case fraction of S. typhi and NTS infections. Certain suggestive clinical features (such as older age and long duration of fever for typhoid whereas concomitant malaria, anemia, jaundice and hypoglycemia for NTS infection) may be used to distinguish invasive salmonellosis from other severe febrile illness.

Evidence of Carriage of Antimicrobial Resistant Salmonella species of Public Health and Veterinary Significance in the Intestines of House Crows (Corvus splendens) in Tanzania

“…S. Typhi is the causative agent of human typhoid fever [15] while S. Gallinarum causes fowl typhoid in birds [16]. Occurrence of S. Gallinarum in chickens [17,18] and S. Typhi in humans [19][20][21], in the country, has been reported in previous studies. The risk of enteric Salmonella infections originating from crows is heightened due to the fact that their population is expanding both in the country and in neighboring countries [17].…”

Dengue and Typhoid Co-infection– Study from a Government Hospital in North Delhi

“…A study from Tanzania supported the long-held hypothesis that malaria in children in that region, preceeds and predisposes invasive Non Typhoidal Salmonella (NTS) infection [18,19]. Although the mechanism underlying the association between malaria and NTS is incompletely understood, the possibility of metabolic, haemodynamic or inflammatory processes occurring during severe malaria predisposing to invasive bacterial disease has not be ruled out [18].…”

“…Although the mechanism underlying the association between malaria and NTS is incompletely understood, the possibility of metabolic, haemodynamic or inflammatory processes occurring during severe malaria predisposing to invasive bacterial disease has not be ruled out [18]. Dengue-typhoid co-infection rate of 7.8% is a high value in itself.…”

First case report of blood and urine cultures positive bacteraemia by Salmonella enterica serotype Choleraesuis from India

“…It primarily has four different clinical manifestations: enteric fever, gastroenteritis, bacteraemia and an asymptomatic carrier state (Coburn et al, 2007). Although systemic infections such as enteric fever caused by serovars Typhi and Paratyphi are common in developing countries such as India (Ochiai et al, 2008), invasive salmonellosis caused by non-typhoidal Salmonella (NTS) species has been more frequently reported from sub-Saharan African countries (Gordon et al, 2008;Mtove et al, 2010) and south-eastern Asian countries such as Taiwan (Chen et al, 2007;Chiu et al, 2004;Jean et al, 2006).While a longer duration of fever and younger age (school age) are associated with typhoid fever, invasive NTS infections are more common in patients with malaria, anaemia, jaundice, hypoglycaemia, malnutrition, HIV infection and other immunosuppressive conditions (Chen et al, 2007;Chiu et al, 2004;Gordon et al, 2008;Mtove et al, 2010).…”