DSpace community: ICDDR,B External Publications

Mortality due to shigellosis: community and hospital data

Mon, 29 Oct 1990 22:58:59 GMT

title: Mortality due to shigellosis: community and hospital data authors: Bennish, Michael L.; Wojtyniak, Bogdan J.
abstract: Almost all fatal cases of shigellosis occur in developing countries, and data on mortality are generally compiled from three sources: investigations of epidemics caused by Shigella dysenteriae type 1, surveillance of endemic diarrheal disease, and reports from hospitals. Attack rates during epidemics of dysentery due to infection with S. dysenteriae type 1 have ranged from 1% to 33%, and case-fatality rates have ranged from 1% to 7%. In Matlab, a rural district in Bangladesh, most diarrhea-related deaths and approximately 25% of all deaths among children 1 through 4 years of age are attributable to dysentery. In 1984, an epidemic of dysentery was associated with a 42% increase in the death rate in that age group. At the Dhaka Treatment Centre of the International Centre for Diarrhoeal Disease Research, Bangladesh, the fatality rate for 970 inpatients with shigellosis was 11% in 1988, with most deaths occurring among malnourished children who were infected with Shigella flexneri. Control of mortality from shigellosis will require prevention of epidemic S. dysenteriae type 1 disease and endemic S. flexneri infections in children who live in countries with a high prevalence of malnutrition

Unusual association of a plasmid with nalidixic acid resistance in an epidemic strain of Shigella dysenteriae type 1 from Asia

Mon, 29 Oct 1990 22:58:59 GMT

title: Unusual association of a plasmid with nalidixic acid resistance in an epidemic strain of Shigella dysenteriae type 1 from Asia authors: Ashraf, M. Musharraf; Ahmed, Zia U.; Sack, David A.
abstract: The association of a 20-MDa plasmid with nalidixic acid resistant (Nalr) strains of Shigella dysenteriae 1 has been examined. The plasmid, which is readily transferable, does not itself code for nalidixic acid resistance but offers a survival advantage to its host under nalidixic acid stress. The plasmid-containing cultures of S. dynsenteriae 1 produced Nalr mutants in vitro at a frequency 1000-fold higher than their plasmidless parent strains, after two exposures to nalidixic acid. Using a similar procedure, mutants resistant to other antibiotics such as chloramphenicol, tetracycline, or ciprofloxacin could not be isolated. The genome of S. dysenteriae 1 appears to carry a heavy load of the insertion sequence IS1. The propensity of the plasmid-containing strains to readily mutate to nalidixic acid resistance and its possible relevance to the observed association of the plasmid with Nalr clinical isolates is discussed

Hafnia alvei, a probable cause of diarrhea in humans

Mon, 29 Oct 1990 22:58:59 GMT

title: Hafnia alvei, a probable cause of diarrhea in humans authors: Albert, M. John; Alam, Khorshed; Islam, Moyenul; Montanaro, Jacqueline; Rahaman, A.S.M. Hamidur; Haider, Khaleda; Hossain, M. Anowar; Kibriya, A.K.M.G.; Tzipori, Saul
abstract: Hafnia alvei, a member of the family Enterobacteriaceae, was the only species of bacteria cultured from the stool of a 9-month-old child who was admitted with a 3-day history of watery diarrhea. The isolated strain of H. alvei failed to produce heat-labile or heat-stable enterotoxins or Shiga-like toxin I or II and did not invade HeLa cells, nor did it cause keratoconjunctivitis (determined by the Sereny test) in a guinea pig's eye. The strain, however, induced diarrhea in 8 of 12 adult rabbits with removable intestinal ties (removable intestinal tie-adult rabbit diarrhea [RITARD] assay) and in 1 of 2 orally fed animals. No diarrhea could be induced with Escherichia coli K-12 in eight RITARD assay rabbits and three orally fed rabbits, respectively. Microscopic examination of affected animals revealed moderate inflammatory cellular infiltration of the intestinal mucosa, in which bacterial attachment to the surface epithelium and loss of the microvillus border were evident in the ileum and colon. Electron microscopy demonstrated cellular modifications of the apical surface, with cupping or pedestal formation and increased terminal web density at sites of bacterial "attachment-effacement," a well-known characteristic and mechanism of diarrhea of enteropathogenic E. coli. Identical lesions were also induced by H. alvei in rabbit ileal loops, which ruled out naturally occurring rabbit enteropathogenic E. coli strains, which are known to produce similar lesions. It is concluded that at least some strains of H. alvei have the potential to cause diarrhea and that attachment-effacement is a virulence characteristic shared by bacteria other than E. coli

Drug resistance of clinical and environmental isolates of vibrio cholera 01

Mon, 29 Oct 1990 22:58:59 GMT

title: Drug resistance of clinical and environmental isolates of vibrio cholera 01 authors: Alam, Munirul; Khan, S.I.; Huq, Anwarul