Ecotoxicological assessment of bauxite residue (red mud) overflow treated by dissolved air flotation (DAF).

In this study, the effluent from the Bayer process of transforming bauxite into alumina, followed by dissolved air flotation (DAF) treatment, was evaluated to identify the best experimental conditions that generate less toxic or nontoxic effluent for discharge. Two freshwater organisms, the Chlorophyceae microalga Raphidocelis subcapitata (96-h algal growth inhibition test), and the microcrustacean Daphnia similis (48-h acute immobility test), were used to analyze the efficiency of effluent treatment by detecting and comparing the toxicity of the treated effluent. Experimental factorial planning used different concentrations of the coagulant ferric chloride and the flocculant Nalco® N-99-005B, and different recycle ratios. The highest recycle ratio (30%) and highest flocculant concentration (150 mg/L) had the best solids removal efficiency, above 90%. Probably the higher concentration of flocculant led to the formation of a more stable froth, promoting an increase in the hydrophobic characteristics of the flocs. Two operating conditions were satisfactory according to acute and chronic bioassays, with removal efficiencies of total suspended solids and turbidity higher than 98%, for both variables. Producers, R. subcapitata microalga, were more sensitive than the primary consumers, D. similis microcrustaceans, indicating the importance of performing tests with different bioindicators.

Epidemiology and the economic assessment of a mumps outbreak in a highly vaccinated population, Orange County, New York, 2009-2010.

Studies assessing the economic burden of a mumps outbreak in a highly vaccinated population are limited. The Orange County Health Department (OCHD), New York State Department of Health (NYS DOH), and the Centers for Disease Control and Prevention conducted a mumps investigation in an affected village with a highly vaccinated population. To understand the epidemiology, standardized mumps case definition and active surveillance were used to identify mumps cases. In addition, an economic assessment of a combined outbreak investigation and third dose measles-mumps-rubella (MMR) vaccine intervention conducted by OCHD and NYS DOH was performed; estimated by retrospectively evaluating public health response-related activities including use of a third dose of MMR vaccine. From September 24, 2009, through June 15, 2010, 790 mumps cases were reported-64% were male and highest attack rate was among 11-17 year age group (99.1 cases per 1000 individuals). Of the 658 cases with known vaccination history, 83.6% had documentation of 2 doses of mumps containing vaccine. No deaths were reported. The 2 major exposure settings were schools (71.8%) and households (22.5%). Approximately 7736 h of public health personnel time were expended with the total approximate cost of US $463,000, including US $34,392 for MMR vaccine-the estimated cost per household was US $827. Mumps continues to be endemic in many parts of the world, resulting in importations into the United States. Large mumps outbreaks similar to this in highly vaccinated populations may require considerable investigation and control activities.

Risk factors for transmission of mumps in a highly vaccinated population in Orange County, NY, 2009-2010.

BACKGROUND: In 2009-2010, we investigated a mumps outbreak among a highly vaccinated Orthodox Jewish population in a village in Orange County, NY, to identify risk factors associated with mumps transmission among persons with 2 doses of mumps-containing vaccine. METHODS: Demographic and epidemiologic characteristics were collected on students in grades 6-12 in 3 schools. A mumps case was defined as a student, who self-reported parotitis, orchitis, jaw swelling and/or a mumps-related complication or whose mumps illness was reported to the Orange County Health Department during September 1, 2009, to January 18, 2010. Log-binomial regression analyses were conducted separately for boys and girls as they attended different schools and had different hours of study. RESULTS: Of the 2503 students with 2 documented doses of mumps-containing vaccine, 320 (13%) developed mumps. Risk of mumps increased with increasing number of mumps cases in the class [≥8 vs. ≤3 cases: boys aRR = 3.1; 95% confidence interval (CI): 2.0-5.0; girls aRR = 2.6; 95% CI: 1.6-4.1] and household (>1 vs. 0 cases: boys aRR = 4.3 95% CI: 3.7-5.6; girls aRR = 10.1 95% CI: 7.1-14.3). Age at first dose, time since last dose, time between first and second dose, school, class size, number of hours at school per week and household size were not significantly associated with having mumps. CONCLUSIONS: Two doses of mumps-containing vaccine may not be as effective in outbreak settings with multiple, prolonged and intense exposure. Additional studies are required to understand why such mumps outbreaks occur and how they can be prevented in the future.

Impact of a third dose of measles-mumps-rubella vaccine on a mumps outbreak.

BACKGROUND AND OBJECTIVE: During 2009-2010, a northeastern US religious community experienced a large mumps outbreak despite high 2-dose measles-mumps-rubella (MMR) vaccine coverage. A third dose of MMR vaccine was offered to students in an affected community in an effort to control the outbreak. METHODS: Eligible sixth- to 12th-grade students in 3 schools were offered a third dose of MMR vaccine. Baseline and follow-up surveys and physician case reports were used to monitor mumps attack rates (ARs). We calculated ARs for defined 3-week periods before and after the intervention. RESULTS: Of 2265 eligible students, 2178 (96.2%) provided documentation of having received 2 previous doses of MMR vaccine, and a high proportion (1755 or 80.6%) chose to receive an additional vaccine dose. The overall AR for all sixth- to 12th-grade students declined from 4.93% in the prevaccination period to 0.13% after vaccination (P < .001). Villagewide, overall AR declined by 75.6% after the intervention. A decline occurred in all age groups but was significantly greater (96.0%) among 11- to 17-year-olds, the age group targeted for vaccination, than among all other age groups. The proportions of adverse events reported were lower than or within the range of those in previous reports of first- and second-dose MMR vaccine studies. CONCLUSIONS: This is the first study to assess the impact of a third MMR vaccine dose for mumps outbreak control. The decline in incidence shortly after the intervention suggests that a third dose of MMR vaccine may help control mumps outbreaks among populations with preexisting high 2-dose vaccine coverage.

Adverse events following a third dose of measles, mumps, and rubella vaccine in a mumps outbreak.

During a 2009-2010 mumps outbreak in a New York State village, a third dose of measles, mumps, and rubella (MMR) vaccine was administered to children in three schools as a control measure. Information on local and systemic adverse events (AE) was collected by a self-report survey distributed to all children in grades 6-12. A comprehensive search for AE following MMR vaccination was conducted using physician records and the Vaccine Adverse Events Reporting System (VAERS). A literature search was performed for published reports pertaining to AE associated with mumps-containing vaccine, using the Jeryl-Lynn strain, from 1969 to 2011. A total of 1755 individuals received the third dose; 1597 (91.0%) returned the survey. Of those, 115 (7.2%) reported at least one local or systemic AE in the 2 weeks following vaccination. The most commonly reported AE were "pain, redness, or swelling at the injection site" (3.6%) and "joint or muscle aches" (1.8%). No serious AE were reported in the survey, physician records or through VAERS. The proportions of AE found in the present study were lower than or within the range of those reported in prior studies of first- and second-dose MMR vaccine studies. The results of this study suggest that a third dose of MMR vaccine administered in an outbreak setting is safe, with injection site reactions reported more frequently than systemic reactions. However, to assess risk for rare or serious AE after a third dose of MMR vaccine, longer term studies would be required.