Outbreak of lower respiratory tract illness associated with human enterovirus 68 among American Indian children.

Human enterovirus 68 (EV68) infections are rarely reported. We describe a respiratory outbreak associated with EV68 among 18 children admitted to a remote Indian Health Service facility during August 11, 2010 through September 14, 2010. Clinical illness was characterized by pneumonia and wheezing. EV68 should be considered as an etiology in outbreaks of lower respiratory tract illness.

The effect of age on transmission of 2009 pandemic influenza A (H1N1) in a camp and associated households.

BACKGROUND: A major portion of influenza disease burden during the 2009 pandemic was observed among young people. METHODS: We examined the effect of age on the transmission of influenza-like illness associated with the 2009 pandemic influenza A (H1N1) virus (pH1N1) for an April-May 2009 outbreak among youth-camp participants and household contacts in Washington State. RESULTS: An influenza-like illness attack rate of 51% was found among 96 camp participants. We observed a cabin secondary attack rate of 42% (95% confidence interval = 21%-66%) and a camp local reproductive number of 2.7 (1.7-4.1) for influenza-like illness among children (less than 18 years old). Among the 136 contacts in the 41 households with an influenza-like illness index case who attended the camp, the influenza-like illness secondary attack rate was 11% for children (5%-21%) and 4% for adults (2%-8%). The odds ratio for influenza-like illness among children versus adults was 3.1 (1.3-7.3). CONCLUSIONS: The strong age effect, combined with the low number of susceptible children per household (1.2), plausibly explains the lower-than-expected household secondary attack rate for influenza-like illness, illustrating the importance of other venues where children congregate for sustaining community transmission. Quantifying the effects of age on pH1N1 transmission is important for informing effective intervention strategies.

Hepatitis C virus infections from unsafe injection practices at an endoscopy clinic in Las Vegas, Nevada, 2007-2008.

BACKGROUND: In January 2008, 3 persons with acute hepatitis C who all underwent endoscopy at a single facility in Nevada were identified. METHOD: We reviewed clinical and laboratory data from initially detected cases of acute hepatitis C and reviewed infection control practices at the clinic where case patients underwent endoscopy. Persons who underwent procedures on days when the case patients underwent endoscopy were tested for hepatitis C virus (HCV) infection and other bloodborne pathogens. Quasispecies analysis determined the relatedness of HCV in persons infected. RESULTS: In addition to the 3 initial cases, 5 additional cases of clinic-acquired HCV infection were identified from 2 procedure dates included in this initial field investigation. Quasispecies analysis revealed 2 distinct clusters of clinic-acquired HCV infections and a source patient related to each cluster, suggesting separate transmission events. Of 49 HCV-susceptible persons whose procedures followed that of the source patient on 25 July 2007, 1 (2%) was HCV infected. Among 38 HCV-susceptible persons whose procedures followed that of another source patient on 21 September 2007, 7 (18%) were HCV infected. Reuse of syringes on single patients in conjunction with use of single-use propofol vials for multiple patients was observed during normal clinic operations. CONCLUSIONS: Patient-to-patient transmission of HCV likely resulted from contamination of single-use medication vials that were used for multiple patients during anesthesia administration. The resulting public health notification of approximately 50,000 persons was the largest of its kind in United States health care. This investigation highlighted breaches in aseptic technique, deficiencies in oversight of outpatient settings, and difficulties in detecting and investigating such outbreaks.

Outbreak of pneumonia associated with emergent human adenovirus serotype 14--Southeast Alaska, 2008.

BACKGROUND: In September 2008, an outbreak of pneumonia associated with an emerging human adenovirus (human adenovirus serotype 14 [HAdV-14]) occurred on a rural Southeast Alaska island. Nine patients required hospitalization, and 1 patient died. METHODS: To investigate the outbreak, pneumonia case patients were matched to control participants on the basis of age, sex, and community of residence. Participants in the investigation and their household contacts were interviewed, and serum samples and respiratory tract specimens were collected. Risk factors were evaluated by means of conditional logistic regression. RESULTS: Among 32 pneumonia case patients, 21 (65%) had confirmed or probable HAdV-14 infection. None of 32 matched control participants had evidence of HAdV-14 infection (P<.001 for the difference). Factors independently associated with pneumonia included contact with a known HAdV-14-infected case patient (odds ratio [OR], 18.3 [95% confidence interval {CI}, >or=2.0]), current smoking (OR, 6.7 [95% CI, >or=0.9]), and having neither traveled off the island nor attended a large public gathering (OR, 14.7 [95% CI, >or=2.0]). Fourteen (67%) of 21 HAdV-14-positive case patients belonged to a single network of people who socialized and often smoked together and infrequently traveled off the island. HAdV-14 infection occurred in 43% of case-patient household contacts, compared with 5% of control-participant household contacts (P = .005). CONCLUSIONS: During a community outbreak in Alaska, HAdV-14 appeared to have spread mostly among close contacts and not widely in the community. Demographic characteristics and illness patterns among the case patients were similar to those observed in other recent outbreaks of HAdV-14 infection in the United States.

Impact of routine hepatitis B immunization on the prevalence of chronic hepatitis B virus infection in the marshall islands and the federated States of micronesia.

BACKGROUND: To evaluate the impact of routine hepatitis B (HB) vaccination on the prevalence of chronic hepatitis B virus (HBV) infection among children in Pacific Island countries where HBV infection was highly endemic, we conducted HB serosurveys during 2000 to 2007 among women of childbearing age born before implementation of HB vaccination and among children born after its implementation. METHODS: Serum specimens were collected from children aged 2 to 6 years and their mothers in Chuuk, Federated States of Micronesia in 2000, children aged 2 to 9 years and their mothers in Pohnpei, Federated States of Micronesia in 2005, and 5- to 9-year-old children and prenatal clinic patients in 2007 in Republic of the Marshall Islands (RMI). Specimens were tested for HB surface antigen (HBsAg) and antibodies to HB core antigen (total anti-HBc). HB vaccination coverage was determined from health department vaccination registries. We defined chronic HBV infection as the presence of HBsAg. RESULTS: Birthdose and 3 dose HB vaccination coverage was 48% and 87%, respectively, in Chuuk, 87% and 90% in Pohnpei, and 49% and 93% in RMI. Chronic HBV infection prevalence among children was 2.5% (9/362) in Chuuk, 1.5% (7/478) in Pohnpei and 1.8% (6/331) in RMI. Chronic HBV infection prevalence among women was 9.2% (21/229) in Chuuk, 4.4% (10/229) in Pohnpei, and 9.5% (11/116) in RMI. CONCLUSIONS: Hepatitis B vaccination has resulted in a substantial decline in chronic infection in children in the Pacific Islands. HB vaccine effectiveness is high in this region, despite challenges in providing HB vaccine at birth and completing vaccination series on schedule.

The epidemiology of hepatitis A virus infections in four Pacific Island nations, 1995-2008.

Historically, hepatitis A virus (HAV) has been highly prevalent in developing countries, with most infections occurring during childhood, when they are likely to be asymptomatic. Shifts in the acquisition of infection from childhood to adulthood, when clinical hepatitis is more likely, may leave populations vulnerable to large outbreaks. We conducted cross-sectional serosurveys from 1995 to 2008 in four Pacific Island nations to determine the proportion of people previously infected with HAV by measuring antibodies to HAV (anti-HAV). In American Samoa, 0.0% of 4- to 6-year-olds (95% CI 0.0-3.7) were anti-HAV positive. In Chuuk, FSM, 8.6% of 2- to 6-year-olds (95% CI 5.7-11.5) were anti-HAV positive compared with 98.3% of individuals > or =16 years old (95% CI 96.6-100). In Pohnpei, FSM, 0.8% of 2- to 9-year-olds (95% CI 0.0-1.6) were anti-HAV positive compared with 95.1% of > or =16 year-olds (95% CI 92.2-98.0). In RMI, 85.7% (95% CI 81.9-89.5) of 4- to 9-year-olds were anti-HAV positive. In Palau, 0.7% of 7- to 8-year-olds were anti-HAV positive (95% CI 0.0-1.8). The low HAV seroprevalence among children in American Samoa, FSM and Palau may indicate a vulnerability to hepatitis A morbidity among these populations. These data will be useful for evaluating the need for hepatitis A surveillance and vaccination programs.

Chronic liver disease among Alaska-Native people, 2003-2004.

OBJECTIVES: A higher proportion of deaths among American-Indian/Alaska-Native (AI/AN) people has been attributed to chronic liver disease (CLD) compared with other racial/ethnic groups in the United States. The objectives of this study were to determine CLD prevalence and to define its etiologies and complications among AN and AI people, who received health care from an urban hospital center. METHODS: We conducted a retrospective, cross-sectional study of AN and AI people > or =18 years old who had at least one patient encounter at the Alaska Native Medical Center during January 2003-December 2004. RESULTS: A total of 1,886 (7.2%) of 26,166 AI/AN people met criteria for having CLD. The most commonly identified etiologies were alcohol-related liver disease (42%), nonalcoholic fatty liver disease (31%), chronic hepatitis C virus infection (26%), and chronic hepatitis B virus infection (8%). Compared with women, men had a higher overall prevalence of CLD (81.9 vs. 64.7 per 1,000), but were less likely to die from a CLD-related cause (1.5 vs. 2.7 per 1,000). These differences in the CLD deaths were mostly attributed to alcohol-related liver disease. CONCLUSIONS: This is the first known population-based study to examine the burden and etiology of CLD among AN people. Causes of CLD were similar among AI/AN people as those reported among other racial/ethnic groups in the United States. Identifying specific etiologies of CLD among populations can help target appropriate prevention and treatment strategies as they are specific to the causes of CLD.

Hepatitis A among international adoptees and their contacts.

We identified 27 cases of hepatitis A among international adoptees (5 persons), their direct or indirect contacts (20 persons), and unvaccinated travelers to the adoptees' countries (2 persons). Most cases occurred among nontraveling contacts of adoptees, suggesting the need to extend prevention guidelines to include hepatitis A vaccination for at-risk nontravelers.