Search

Haemophilus influenzae type b (Hib) is now recognized as an important pathogen in Asia. To evaluate disease susceptibility, and as a marker of Hib transmission before routine immunization was introduced in Kathmandu, 71 participants aged 7 months-77 years were recruited and 15 cord blood samples were collected for analysis of anti-polyribosylribitol phosphate antibody levels by enzyme-linked immunosorbent assay. Only 20% of children under 5 years old had levels considered protective (>0.15 µg/ml), rising to 83% of 15-54 year-olds. Prior to introduction of Hib vaccine in Kathmandu, the majority of young children were susceptible to disease.

Background: Haemophilus influenzae type b (Hib) carriage and disease studies in Nepali children suggest a significant burden of infection. Hib conjugate vaccines (HibCV) do not have uniform immunogenicity between populations. We determined the immunogenicity of HibCV in Nepali infants, before its introduction into the routine immunization schedule., Methods: Ninety infants recruited at Patan Hospital, Kathmandu, received 3 doses of the HibCV with routine immunizations (diphtheria, tetanus, whole cell pertussis-hepatitis B vaccine + oral polio vaccine) at 6, 10 and 14 weeks of age, and a HibCV booster at 52 weeks. Anti-polyribosylribitol phosphate (PRP) concentrations were measured at 18, 52 and 56 weeks, and the antibody persistence at 52 weeks was compared with antibody values in unimmunized controls (n = 30)., Results: After 3 doses of primary immunizations, at 18 weeks of age (n = 74), all infants had anti-PRP concentrations above the accepted thresholds for short- and long-term protection (0.15 and 1.0 µg/mL, respectively). At 1 year of age, before administration of the booster of HibCV, the anti-PRP geometric mean antibody concentration was 2.76 µg/mL (confidence interval: 1.88-4.07) in sera from the immunized children compared with 0.11 µg/mL (95% confidence interval: 0.08-0.17) in the nonimmunized control group (n = 30). Twenty-seven percent (20/74) of participants, however, had anti-PRP concentrations <1.0 µg/mL. Four weeks after the booster dose of HibCV, 98.5% of infants had anti-PRP concentrations above 1.0 µg/mL., Conclusion: Immunization with HibCV given as part of the Expanded Program on Immunization schedule in Nepal elicits robust antibody responses. Though the antibody wanes during the first year of life, most 1-year-old infants remain protected and respond robustly to a booster dose of the vaccine.

The bacteriologic and clinical effects of early antibiotic treatment of Campylobacter jejuni enteritis were studied. Erythromycin rapidly eliminated C. jejuni from stools, whereas trimethoprim-sulfamethoxazole did not. Despite its bacteriologic effectiveness, erythromycin did not reduce the duration or severity of diarrhea, abdominal pain, or other symptoms.

The appropriate approach to the diagnosis and management of acute infectious diarrhea is determined by the frequency and setting of the illness, the recognizable causes or syndromes, the cost and yield of available diagnostic tests, and the treatability of the disease. Acute diarrhea affects everyone throughout the world from one to more than six times each year, depending on age, location, and living conditions. The range of identifiable viral, bacterial, and parasitic etiologies is great, and the cost of indiscriminate use of etiologic studies for diagnosis is prohibitive. Because of its insensitivity for many organisms and poor selection of cases for testing, routine stool culture has been one of the most costly and ineffective microbiologic tests; the cost per positive result has traditionally exceeded $900 to $1,000. The appropriate treatment for the vast majority of cases (independent of their cause) is simple and effective: oral glucose- and electrolyte-containing rehydration solution. On the basis of an appropriate history and understanding of pathogenesis, fecal specimens can be selectively obtained and promptly examined for leukocytes and parasites, and the common noninflammatory diarrheas can be separated from the inflammatory infections in order to focus further studies on the latter group. The bacteria for which specific antimicrobial therapy should be considered usually cause inflammatory diarrhea in the United States. Therefore, only when the history or fecal leukocyte findings indicates an inflammatory process is it appropriate to culture for the routine invasive bacterial pathogens. In sporadic inflammatory diarrhea, culture methods should include those for Campylobacter jejuni as well as Salmonella and Shigella. Several special circumstances may prompt a consideration of parasites (including Giardia, Entamoeba, Strongyloides, Cryptosporidium), Vibrio, Yersinia, Clostridium difficile, enterotoxigenic Escherichia coli, food-borne agents, or sexually transmitted pathogens. The practical value of specific identification of rotaviruses (by enzyme-linked immunosorbent assay, Rotazyme, or electron microscopy) is primarily epidemiologic, particularly in hospitalized infants or young children. Using such a selective approach to fecal culture will greatly increase its yield and can reduce the cost per positive result from $1,000 to less than $150.