Long Term Protection by and Persistence of Vi Antibodies Induced by Vi-rEPA Conjugate Vaccines in Vietnamese Children Injected at 2-5 Years or at 5-8 Years of Age
Condition: Typhoid Fever
MeSH terms: Typhoid Fever
Study type: Observational

Summary: 
      Typhoid fever remains an important cause of morbidity and mortality in the developing world.
      It is estimated that more than 16 million cases and about 600,000 deaths occur annually, most
      of which occur in Southeast Asia and Africa. Ingestion of food or water contaminated by
      acutely infected persons or chronic carriers is the most common form of transmission. As a
      result, typhoid fever is prevalent where unsafe drinking water or contaminated food is
      common.

      Typhoid fever is highly endemic in Vietnam, especially in the southern provinces and is a
      significant disease in both preschool and school-aged children. Data from Dong Thap
      Provincial Hospital, Mekong delta region showed that among 3,934 hospitalized typhoid fever
      cases from 1990 to 1995, 4.2% had complications and 0.8% died.

      Typhoid fever has become difficult and expensive to treat. About 90% of Salmonella typhi
      isolates are of multidrug-resistant (resistant to chloramphenicol, ampicillin, and
      trimethoprim-sulfamethoxazole) and 76% of isolates showed reduced susceptibility to
      fluoroquinolones. Isolates with full fluoroquinolone or extended spectrum cephalosporin
      resistance have not yet reported in Vietnam but occur sporadically in the Indian
      subcontinent. If they become widespread, alternative treatment options will be limited. The
      improvement of sanitation, provision of safe water and elimination of chronic carriage is not
      expected to be achieved quickly. Accordingly, vaccination against typhoid fever is
      increasingly important national public health priority.
    

Detailed description: 
      Typhoid fever remains an important cause of morbidity and mortality in the developing world.
      It is estimated that more than 16 million cases and about 600,000 deaths occur annually, most
      of which occur in Southeast Asia and Africa. Ingestion of food or water contaminated by
      acutely infected persons or chronic carriers is the most common form of transmission. As a
      result, typhoid fever is prevalent where unsafe drinking water or contaminated food is
      common.

      Typhoid fever is highly endemic in Vietnam, especially in the southern provinces, and is a
      significant disease in both preschool and school-aged children. Data from Dong Thap
      Provincial Hospital, Mekong delta region showed that among 3,934 hospitalized typhoid fever
      cases from 1990 to 1995, 4.2% had complications and 0.8% died.

      Typhoid fever has become difficult and expensive to treat. About 90% of Salmonella typhi
      isolates are of multidrug-resistance (resistant to chloramphenicol, ampicillin, and
      trimethoprim-sulfamethoxazole) and 76% of isolates showed reduced susceptibility to
      fluoroquinolones. Isolates with full fluoroquinolone or extended spectrum cephalosporin
      resistance have not been reported yet in Vietnam but occur sporadically in the Indian
      subcontinent. If they become widespread, alternative treatment options will be limited. The
      improvement of sanitation, provision of safe water and elimination of chronic carriage are
      not expected to be achieved quickly. Accordingly, vaccination against typhoid fever is an
      increasingly important national public health priority.
    

Time perspective: Other
Keywords: Typhoid Fever; Serological Survey; Follow-Up; Protection