The California Pertussis Epidemic 2010: A Review of 986 Pediatric Case Reports From San Diego County.

BACKGROUND: The California Department of Public Health (CDPH) declared a pertussis epidemic on 23 June 2010. More cases were reported in 2010 (9146) than in any year since 1947. We describe the characteristics of pertussis epidemiology and disease from 986 reported cases in children in San Diego County (population 3.2 million). METHODS: Descriptive statistics were abstracted from CDPH pertussis case report forms that were completed by public health nurses investigating reports of positive laboratory results for pertussis and reports of illnesses compatible with pertussis. RESULTS: Of 1144 reported adult and pediatric cases, 753 (66%) were confirmed and 391 were probable/suspect. Children aged <19 years comprised 86% of all reported cases in San Diego County; of these, 22% were aged 11-18 years, 29% were aged 6-10 years, 27% were aged 1-5 years, and 22% were aged <1 year (with 70% aged <6 months). Case rates were highest in infants aged <6 months (651 per 100 000 population). Of those aged >1 year, the highest attack rates were in preschool children aged 1-5 years (114 per 100 000) and elementary school children aged 6-10 years (141 per 100 000). Of 51 children hospitalized, 82% were aged <6 months; 2 deaths occurred in these young infants. Paroxysmal cough was noted in over 70% of children in all age groups; post-tussive vomiting occurred in 36% (aged 11-18 years) to 57% (aged <6 months) of children. CONCLUSIONS: Pertussis vaccine efficacy may decrease more rapidly than previously believed, facilitating spread of pertussis in elementary school-aged children. The highest case rates and the only mortality occurred in infants aged <6 months.

Studies of the 1996-1997 inactivated influenza vaccine among children attending day care: immunologic response, protection against infection, and clinical effectiveness.

A randomized, blinded, pilot study of influenza vaccine administered to children attending day care centers was conducted during the 1996-1997 winter. Vaccine efficacy in preventing serologically proven influenza virus infection was 0.45 (95% confidence limit [CL]: -0.02, 0.69) for influenza B and 0.31 (95% CL: -0.95, 0.73) for influenza A(H3N2). For both influenza A(H3N2) and B, children without preexisting hemagglutination inhibition (HI) antibody to these antigens had lower antibody responses to vaccine, were less likely to develop a serological response, and were more likely to develop serological evidence of influenza infection. Although there were no reductions in respiratory or febrile respiratory illnesses among all vaccinated children, there was a trend for reductions in such illnesses among vaccinated children with preexisting HI antibodies to influenza A(H3N2) and B. Therefore, immunologic priming in young children may be important for vaccine response and for protection against infection. Larger studies are needed in other influenza seasons to assess vaccine efficacy and clinical effectiveness.

Predictors of human immunodeficiency virus counseling and testing among sexually transmitted disease clinic patients.

OBJECTIVES: To determine the predictors of prior or current, and repeat human immunodeficiency virus (HIV) testing. STUDY DESIGN: Cross-sectional survey. METHODS: Sexually transmitted disease (STD) clinic patients who participated in a blinded HIV seroprevalence survey completed a voluntary questionnaire regarding their reasons for accepting or declining HIV testing. RESULTS: Eighty-seven percent of participants reported a previous HIV test or were HIV testing the day they completed the questionnaire. African Americans were less likely to have been HIV tested (adjusted odds ratio 0.3, 95% confidence limits, 0.1, 0.8). The most common reasons for testing were to be reassured and to receive medical care if infected. The most common reason for not testing was that nontesters did not think that they were infected. Repeated testing was reported by 51% of the participants and was more frequent among patients who were older or members of high-risk groups (P < 0.05). Patients tested repeatedly to confirm a prior HIV test result or because of continued risky behavior. CONCLUSIONS: Testing for HIV is frequent among STD clinic patients but less so among African Americans. Receipt of medical care appears to be an important motivation for HIV testing, whereas lack of perceived risk may discourage testing. Continued high-risk behavior contributes to repeat HIV testing.

HIV transmission through donor artificial insemination.

OBJECTIVE: To investigate and report cases of human immunodeficiency virus (HIV) transmission through donor artificial insemination (AI) before 1986 at five infertility clinics. DESIGN: Two types of look-back studies were performed: (1) identification of an HIV-infected woman who reported previous AI, followed by identification of the infected donor(s) and contact tracing of women who were inseminated with his semen, and (2) identification of an HIV-infected donor and subsequent examination of women receiving AI procedures using his semen. SETTING: Five infertility clinics in Los Angeles County, California; San Diego County, California; Arizona; and Vancouver, British Columbia. PATIENTS: A total of 230 women were inseminated with semen from any one of the five identified HIV-infected donors; 199 (87%) consented to HIV testing. MAIN OUTCOME MEASURE: Seropositivity for HIV among AI recipients. RESULTS: Seven (3.52%) of the 199 women (95% confidence interval, 1.55% to 7.41%) who were artificially inseminated with semen from any of five HIV-infected donors and consented to HIV testing tested HIV-seropositive. Information on HIV risk was available for three of the five donors; all three reported a history of having sex with men. Four HIV-infected women were identified through uncommon circumstances, rather than through routine look-back studies of donors. CONCLUSION: Infection with HIV through donor AI performed before routine HIV screening of semen donors represents a potentially serious threat to women who underwent AI procedures. Public health policies requiring retrospective identification of HIV-infected semen donors and patients receiving AI before 1986, especially in acquired immunodeficiency syndrome (AIDS)-prevalent areas, should be considered routine. Women diagnosed with AIDS or HIV infection, in whom no identified risk of HIV acquisition is established, should be questioned about previous AI procedures.

Occurrence of hepatitis A, B, and non-A/non-B in the United States. CDC sentinel county hepatitis study I.

To determine the relative occurrence of hepatitis A, B, and non-A/non-B in the United States, serum samples and epidemiologic data were collected from patients with hepatitis in five selected counties. Overall, 41, 33, and 26 percent of the patients had hepatitis A, hepatitis B, and hepatitis non-A/non-B, respectively. The incidence, especially of hepatitis A, varied considerably. All three types of hepatitis occurred more frequently in those 15 to 44 years of age. Hepatitis A predominated in those less than 15 years of age and non-A/non-B predominated in those older than 44 years. There was a male predominance (65 to 62 percent) for hepatitis A and hepatitis B, but non-A/non-B occurred equally in both sexes. There was no seasonal pattern for any type. Risk factors for hepatitis A were previous contact with a patient with hepatitis (26 percent), homosexual (male) preference (15 percent), and day-care center contact (11 percent). For hepatitis B, risk factors included drug use (26 percent), previous contact with an infected person (22 percent), homosexual preference (12 percent), and a health-care occupation (12 percent). For hepatitis non-A/non-B, risk factors included drug use (16 percent), transfusion (12 percent), and previous contact with an infected person (12 percent). Previous hospitalization appeared to be a risk factor for both hepatitis B and hepatitis non-A/non-B.