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Epidemic diphtheria reemerged in the republic of Georgia in November 1993. To identify risk factors for fatal outcomes, clinical and epidemiologic data on all hospitalized diphtheria patients were examined. Medical charts of patients from 1993-1995 were reviewed. A total of 659 cases and 68 deaths were identified (case fatality rate [CFR] = 10.3%). Fifty-two percent of all cases and 68% of deaths were in children 3 days) between onset of symptoms to antitoxin treatment were significantly associated with fatal outcomes. Immunization of children and 40- to 49-year-old adults was required to rapidly control the epidemic.  相似文献   
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This study was performed to determine the risk of family members of anti-hepatitis C virus (HCV)-positive hemophilia patients (index patients) for infection with HCV compared with the risk of acquiring hepatitis B virus (HBV), human immunodeficiency virus (HIV), and hepatitis A virus (HAV) infection. All index patients (n = 141) were found to be positive by first and second generation anti-HCV enzyme immunoassays (EIAs). Among their household contacts (n = 228), 224 were negative and 1 positive by both assays. Three contacts gave positive results in first generation anti-HCV EIA and negative results in second generation assay. This latter result was confirmed by further tests (neutralization test, synthetic peptides, and supplemental assay). Percent positivity for anti-HBc was about the same in non-sexual household contacts and sexual partners (13 of 109 [12%] and 7 of 54 [13%], respectively). Percent prevalence of anti-HBc was higher in contacts of index patients with chronic hepatitis B than in those of index patients who had recovered from that disease (6 of 20 [30%] and 14 of 133 [10%], respectively; P < .05). The HBV infection rate of contacts participating in controlled self-treatment was not higher than that of controls (3 of 57 [5%] and 10 of 98 [10%], respectively). Of 44 sexual partners, 5 (11%) were found to be positive for anti-HIV. Prevalence of anti-HAV matched with the age-related distribution in the German population. These findings suggest that intrafamilial transmission of HCV to family members of hemophilia patients is uncommon. In contacts of hemophilia patients, the risk of acquiring HBV infection seems to be as high in household contacts as in sexual contacts. Participation in controlled self-treatment does not appear to be an additional risk for HCV and HBV infection. There is no doubt that sexual transmission of HCV is less common than that of HBV and HIV.  相似文献   
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During 2012, Sierra Leone experienced a cholera epidemic with 22,815 reported cases and 296 deaths. We conducted a matched case-control study to assess risk factors, enrolling 49 cases and 98 controls. Stool specimens were analyzed by culture, polymerase chain reaction (PCR), and pulsed-field gel electrophoresis (PFGE). Conditional logistic regression found that consuming unsafe water (matched odds ratio [mOR]: 3.4; 95% confidence interval [CI]: 1.1, 11.0), street-vended water (mOR: 9.4; 95% CI: 2.0, 43.7), and crab (mOR: 3.3; 95% CI: 1.03, 10.6) were significant risk factors for cholera infection. Of 30 stool specimens, 13 (43%) showed PCR evidence of toxigenic Vibrio cholerae O1. Six specimens yielded isolates of V. cholerae O1, El Tor; PFGE identified a pattern previously observed in seven countries. We recommended ensuring the quality of improved water sources, promoting household chlorination, and educating street vendors on water handling practices.  相似文献   
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Access to safe drinking water and improved hygiene are essential for preventing diarrheal diseases. To integrate hygiene improvement with antenatal care, free hygiene kits (water storage containers, water treatment solution, soap) and educational messages were distributed to pregnant women at antenatal clinics in Malawi. We assessed water treatment and hygiene practices of 275 non-pregnant friends and relatives of the hygiene kit recipients at baseline and follow-up nine months later to measure program impact on non-participants in the same communities. At follow-up, friends and relatives who did not receive kits or education were more likely than at baseline to purchase and use water treatment solution (25% versus 1%; P < 0.0001) and demonstrate correct handwashing practices (60% versus 18%; P < 0.0001). This antenatal clinic-based program resulted in improved water treatment and hygiene behaviors among non-pregnant friends and relatives living in the same communities as hygiene kit recipients, suggesting that program benefits extended beyond direct beneficiaries.  相似文献   
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