Characterization of chronic hepatitis B cases among foreign-born persons in six population-based surveillance sites, United States 2001-2010.

National surveys indicate prevalence of chronic hepatitis B among foreign-born persons in the USA is 5.6 times higher than US-born. Centers for Disease Control and Prevention funded chronic hepatitis B surveillance in Emerging Infections Program sites. A case was any chronic hepatitis B case reported to participating sites from 2001 to 2010. Sites collected standardized demographic data on all cases. We tested differences between foreign- and US-born cases by age, sex, and pregnancy using Chi square tests. We examined trends by birth country during 2005-2010. Of 36,008 cases, 21,355 (59.3%) reported birth in a country outside the USA, 2,323 (6.5%) were US-born. Compared with US-born, foreign-born persons were 9.2 times more frequent among chronic hepatitis B cases. Foreign-born were more frequently female, younger, ever pregnant, and born in China. Percentages of cases among foreign-born persons were constant during 2005-2010. Our findings support information from US surveillance for Hepatitis B screening and vaccination efforts.

Epidemiology of the viral hepatitis-HIV syndemic in San Francisco: a collaborative surveillance approach.

OBJECTIVES: To describe the epidemiology of people coinfected with hepatitis B virus (HBV) or hepatitis C virus (HCV) and HIV in San Francisco, the San Francisco Department of Public Health's Communicable Disease Control and Prevention Section and the HIV Epidemiology Section collaborated to link their registries. METHODS: In San Francisco, hepatitis reporting is primarily through passive laboratory-based surveillance, and HIV/AIDS reporting is primarily through laboratory-initiated active surveillance. We conducted the registry linkage in 2010 using a sequential algorithm. RESULTS: The registry match included 31,997 HBV-infected people who were reported starting in 1984; 10,121 HCV-infected people who were reported starting in 2001; and 34,551 HIV/AIDS cases reported beginning in 1981. Of the HBV and HCV cases, 6.3% and 12.6% were coinfected with HIV, respectively. The majority of cases were white males; however, black people were disproportionately affected. For more than 90% of the HBV/HIV cases, male-to-male sexual contact (men who have sex with men [MSM]) was the risk factor for HIV infection. Injection drug use was the most frequent risk factor for HIV infection among the HCV/HIV cases; however, 35.6% of the HCV/HIV coinfected males were MSM but not injection drug users. CONCLUSIONS: By linking the two registries, we found new ways to foster collaborative work and expand our programmatic flexibility. This analysis identified particular populations at risk for coinfection, which can be used by viral hepatitis and HIV screening, prevention, and treatment programs to integrate, enhance, target, and prioritize prevention services and clinical care within the community to maximize health outcomes.

Knowledge of hepatitis B risk factors and prevention practices among individuals chronically infected with hepatitis B in San Francisco, California.

Asian/Pacific Islanders (A/PIs) in the United States are disproportionately affected by the hepatitis B virus (HBV), which can cause a lifelong liver infection that may result in cirrhosis, liver failure, liver cancer, or death. Although previous studies have measured knowledge of hepatitis B transmission and prevention practices in A/PI communities, we present results from the first population-based study of this type, which specifically focuses on A/PIs who are chronically infected with HBV. Through telephone interviews, we assessed the HBV risk factor knowledge and prevention practices of a population-based, random sample of persons with chronic HBV who were reported to the San Francisco Department of Public Health between October 2007 and July 2009. Among 829 respondents, 67% were foreign born A/PIs of Chinese ethnicity who did not speak English as their primary language. Among all respondents, 75% were unable to identify how they acquired HBV, and 41% said that they do nothing to prevent transmission of HBV to their close contacts. Knowledge of HBV risk factors and recommended prevention practices was poor among A/PIs who are chronically infected with HBV and who may transmit the infection to others.

Case-control study of shigellosis in San Francisco: the role of sexual transmission and HIV infection.

BACKGROUND: Shigella species infect approximately 450,000 persons annually in the United States. Person-to-person transmission of Shigella species, which have a low infectious dose, occurs frequently, particularly in areas with poor sanitation and hygiene. Sexual transmission of Shigella species among men who have sex with men (MSM) has been inferred from outbreaks of shigellosis among that population, and limited studies have suggested the importance of human immunodeficiency virus (HIV) infection as a risk factor for shigellosis. No population-based study of sporadic shigellosis has evaluated the role of sexual practices (especially among MSM) and HIV infection along with other established risk factors for shigellosis. METHODS: We conducted a population-based case-control study of shigellosis in adults in San Francisco, California, during the period 1998-1999. Cases of Shigella infection were identified through laboratory-based active surveillance conducted by the California Emerging Infections Program. Seventy-six case patients were matched by sex with 146 control subjects. Exposure data were collected on established risk factors, sexual practices, and HIV infection status. Bivariable and multivariable analyses were conducted. Population-attributable fractions were calculated. RESULTS: From the multivariable analysis, for men, shigellosis was associated with MSM (odds ratio [OR], 8.24; 95% confidence interval [CI], 2.70-25.2), HIV infection (OR, 8.17; 95% CI, 2.71-24.6), direct oral-anal contact (OR, 7.50; 95% CI, 1.74-32.3), and foreign travel (OR, 20.0; 95% CI, 5.26-76.3), with population-attributable fractions of 0.72, 0.42, 0.31, and 0.18, respectively. For women, shigellosis was associated only with foreign travel (OR, 21.0; 95% CI, 2.52-899), with a population-attributable fraction of 0.37. CONCLUSIONS: Among MSM, shigellosis is predominantly a sexually transmitted disease, with direct oral-anal contact conferring the highest risk and HIV infection likely contributing to increased host susceptibility.

FoodNet estimate of the burden of illness caused by nontyphoidal Salmonella infections in the United States.

To determine the burden of Salmonella infections in the United States, Foodborne Diseases Active Surveillance Network (FoodNet) investigators conducted population-based active surveillance for culture-confirmed Salmonella infections during 1996-1999 at FoodNet laboratories. In addition, all clinical microbiology FoodNet laboratories were surveyed to determine their practices for isolating Salmonella. Telephone interviews were also conducted among residents of the FoodNet sites to determine the proportion of persons with diarrheal illness who sought medical care and the proportion who submitted stool specimens for bacterial culture. Using our model, we estimated that there were 1.4 million nontyphoidal Salmonella infections in the United States, resulting in 168,000 physician office visits per year during 1996-1999. Including both culture-confirmed infections and those not confirmed by culture, we estimated that Salmonella infections resulted in 15,000 hospitalizations and 400 deaths annually. These estimates indicate that salmonellosis presents a major ongoing burden to public health.

Invasive Salmonella infections in the United States, FoodNet, 1996-1999: incidence, serotype distribution, and outcome.

Invasive Salmonella infections are severe and can be life threatening. We analyzed population-based data collected during 1996-1999 by the Foodborne Diseases Active Surveillance Network (FoodNet), to determine the incidences, infecting serotypes, and outcomes of invasive Salmonella infection. We found that the mean annual incidence of invasive salmonellosis was 0.9 cases/100,000 population and was highest among infants (7.8 cases/100,000). The incidence was higher among men than women (1.2 vs. 0.7 cases/100,000; P<.001) and higher among blacks, Asians, and Hispanics than among whites (2.5, 2.0, and 1.3 cases/100,000 population, respectively, vs. 0.4 cases/100,000; all P<.001). Seventy-four percent of cases were caused by 8 Salmonella serotypes: Typhimurium, Typhi, Enteritidis, Heidelberg, Dublin, Paratyphi A, Choleraesuis, and Schwarzengrund. Of 540 persons with invasive infection, 386 (71%) were hospitalized and 29 (5%) died; 13 (45%) of the deaths were among persons aged > or =60 years. Invasive Salmonella infections are a substantial health problem in the United States and contribute to hospitalizations and deaths.

Epidemiology of sporadic Campylobacter infection in the United States and declining trend in incidence, FoodNet 1996-1999.

Campylobacter species are a leading cause of foodborne illness in the United States, but few population-based data describing patterns and trends of disease are available. We summarize data on culture-confirmed cases of Campylobacter infection reported during 1996-1999 to the Foodborne Diseases Active Surveillance Network (FoodNet) system. The average annual culture-confirmed incidence was 21.9 cases/100,000 population, with substantial site variation (from 43.8 cases/100,000 population in California to 12.2 cases/100,000 population in Georgia). The incidence among male subjects was consistently higher than that among female subjects in all age groups. The incidence trended downward over the 4 years, with incidences of 23.6, 25.2, 21.4, and 17.5 cases/100,000 population for 1996-1999, respectively--a 26% overall decrease. This trend was sharpest and most consistent in California. Overall, we estimate that ~2 million people were infected with Campylobacter in the United States each year during this time period. Although the number of Campylobacter infections appears to have decreased in the United States during 1996-1999, the disease burden remains significant, which underscores the need to better understand how the disease is transmitted.

Trends in population-based active surveillance for shigellosis and demographic variability in FoodNet sites, 1996-1999.

Shigella is a common cause of diarrhea in the United States, and accurate surveillance is needed to determine the burden of illness that they cause. Active surveillance for culture-confirmed Shigella infection was done as part of the Foodborne Diseases Active Surveillance Network (FoodNet). A total of 4317 cases of shigellosis were reported during 1996-1999 in the original FoodNet surveillance areas. The average annual incidence was 7.4 cases/100,000 population. The incidence was similar during 1996-1998, but it declined in 1999 to 5.0 cases/100,000 population. State-to-state variability was seen in the incidence of shigellosis. Higher incidence was observed in California and Georgia. Shigella sonnei accounted for 70% of the infections, followed by Shigella flexneri (24%). Compared with other age groups, the incidence was highest among children aged 1-4 years of (36.3 cases/100,000 population). Marked demographic differences were observed between infections with S. sonnei and S. flexneri.

Laboratory practices for stool-specimen culture for bacterial pathogens, including Escherichia coli O157:H7, in the FoodNet sites, 1995-2000.

In 2000, we surveyed microbiologists in 388 clinical laboratories, which tested an estimated 339,000 stool specimens in 1999, about laboratory methods and policies for the routine testing of stool specimens for Salmonella, Shigella, Campylobacter, and Vibrio species, Yersinia entercolitica, and Escherichia coli O157:H7. The results were compared with those of similar surveys conducted in 1995 and 1997. Although these laboratories reported routinely testing for Salmonella, Shigella, and Campylobacter species, only 57% routinely tested for E. coli O157:H7, 50% for Y. entercolitica, and 50% for Vibrio species. The mean proportions of stool specimens that yielded these pathogens were as follows: Campylobacter, 1.3% of specimens; Salmonella, 0.9%; Shigella, 0.4%; and E. coli O157:H7, 0.3%. The proportion of laboratories that routinely tested for E. coli O157:H7 increased from 59% in 1995 to 68% in 2000; however, the proportion of stool specimens tested decreased from 53% to 46%. E. coli O157:H7 should be routinely sought in stool specimens submitted for microbiologic culture.

Physicians as food-safety educators: a practices and perceptions survey.

An estimated 4 million bacterial foodborne illnesses occur in the United States annually. Many of these illnesses can be prevented by educating the public about food-safety practices. We investigated both the role of physicians as food-safety educators and the barriers to providing food-safety information. Participants were randomly selected physicians (n=3117) practicing within the surveillance area of the Foodborne Diseases Active Surveillance Network; 1100 were included in the study. Although only 331 (30%) of 1110 respondents provided food-safety information to their patients, 524 (68%) of 769 who did not provide information expressed interest in doing so. Physicians were more likely to provide food-safety information to patients if they perceived foodborne disease to be a serious problem, perceived food-safety education as their role, felt that patients perceived them as a valuable resource for food-safety advice, or felt comfortable making food-safety recommendations. A national physician education campaign that addresses barriers in food-safety education could improve food-safety education by physicians.

Reptiles, amphibians, and human Salmonella infection: a population-based, case-control study.

To estimate the burden of reptile- and amphibian-associated Salmonella infections, we conducted 2 case-control studies of human salmonellosis occurring during 1996-1997. The studies took place at 5 Foodborne Diseases Active Surveillance Network (FoodNet) surveillance areas: all of Minnesota and Oregon and selected counties in California, Connecticut, and Georgia. The first study included 463 patients with serogroup B or D Salmonella infection and 7618 population-based controls. The second study involved 38 patients with non-serogroup B or D Salmonella infection and 1429 controls from California only. Patients and controls were interviewed about contact with reptiles and amphibians. Reptile and amphibian contact was associated both with infection with serogroup B or D Salmonella (multivariable odds ratio [OR], 1.6; 95% confidence interval [CI], 1.1-2.2; P<.009) and with infection with non-serogroup B or D Salmonella (OR, 4.2; CI, 1.8-9.7; P<.001). The population attributable fraction for reptile or amphibian contact was 6% for all sporadic Salmonella infections and 11% among persons <21 years old. These data suggest that reptile and amphibian exposure is associated with approximately 74,000 Salmonella infections annually in the United States.

Persistent diarrhea, arthritis, and other complications of enteric infections: a pilot survey based on California FoodNet surveillance, 1998-1999.

Numerous complications of enteric infections have been described, including persistent diarrhea, reactive arthritis, and Guillain-Barre syndrome. We determined the frequency of self-reported complications of enteric infections in a pilot study in the California site of the Foodborne Diseases Active Surveillance Network. From 1 April 1998 through 31 March 1999, active surveillance identified 1454 infections in Alameda and San Francisco counties, of which 52% were Campylobacter infections, 22% were Salmonella infections, 15% were Shigella infections, 6% were Cryptosporidium infections, 2% were Escherichia coli O157:H7 infections, 2% were Yersinia infections, and 1% were Vibrio infections. We mailed surveys to 1331 eligible participants, and 571 (43%) were returned. A new health problem following infection was reported by 153 (27%) of the respondents: 12 (8%) reported new onset of joint pain and 53 (35%) reported new gastrointestinal symptoms, of whom 38 reported persistent diarrhea, including 2 who reported irritable bowel syndrome. Three respondents reported hair loss. The frequency, nature, and etiology of these complications merit further investigation.