Airborne Infection with Bacillus anthracis��from Mills to Mail

The lack of identified exposures in 2 of the 11 cases of bioterrorism-related inhalation anthrax in 2001 raised uncertainty about the infectious dose and transmission of Bacillus anthracis. We used the Wells-Riley mathematical model of airborne infection to estimate 1) the exposure concentrations in postal facilities where cases of inhalation anthrax occurred and 2) the risk for infection in various hypothetical scenarios of exposure to B. anthracis aerosolized from contaminated mail in residential settings. These models suggest that a small number of cases of inhalation anthrax can be expected when large numbers of persons are exposed to low concentrations of B. anthracis. The risk for inhalation anthrax is determined not only by bacillary virulence factors but also by infectious aerosol production and removal rates and by host factors.     

Bacillus anthracis aerosolization associated with a contaminated mail sorting machine

On October 12, 2001, two envelopes containing Bacillus anthracis spores passed through a sorting machine in a postal facility in Washington, D.C. When anthrax infection was identified in postal workers 9 days later, the facility was closed. To determine if exposure to airborne B. anthracis spores continued to occur, we performed air sampling around the contaminated sorter. One CFU of B. anthracis was isolated from 990 L of air sampled before the machine was activated. Six CFUs were isolated during machine activation and processing of clean dummy mail. These data indicate that an employee working near this machine might inhale approximately 30 B. anthracis-containing particles during an 8-h work shift. What risk this may have represented to postal workers is not known, but this estimate is approximately 20-fold less than a previous estimate of sub-5 micro m B. anthracis-containing particles routinely inhaled by asymptomatic, unvaccinated workers in a goat-hair mill.     

Airborne micro-organisms and prevalence of byssinotic symptoms in cotton mills

The concentration of airborne microbes, their endotoxins and the prevalence of byssinotic symptoms among workers were measured in the cardrooms of seven cotton spinning, a wool spinning and two cotton waste mills and in a dusty workroom of a group of five willowing mills, a tea-packing plant and a pipe tobacco factory. The concentration of microbes cultured on endoagar plates were found to correlate with byssinosis prevalence (r greater than 0.95, P less than 0.001). The concentration of nutrient agar microbes correlated with prevalence less well (r greater than 0.77, P less than 0.01) and that of fungi and endotoxins not at all.     

Patterns of non-response to a mail survey

This paper describes a basic investigation of possible non-response bias in a mail survey. We compare characteristics of responders and non-responders to a mail survey of health outcomes among participants of a longitudinal study of physical activity, physical fitness, and health. Results indicate that, at the first clinic visit, the responders were essentially the same as the non-responders on personal health history and laboratory measurements, while reporting significantly more family history of specific chronic diseases (cardiovascular disease, hypertension, stroke). The male responders were younger and reported more positive health behaviors as well as better weight and treadmill times at the first clinic visit. These results suggest that both response groups were equally healthy at entry, and that individuals who had family members with certain chronic conditions and who had positive health behaviors were more likely to respond (participate) in this health-related survey. Differences of this type could affect interpretation of future analyses. This work illustrates the importance of incorporating methods to examine non-response into any epidemiologic study.     

Using direct mail to prompt smokers to call a quitline

Telephone quitlines efficiently deliver cessation services, but few smokers use them. This article describes an unsolicited direct mail campaign designed to increase calls to the New York State Smokers' Quitline. Two post-cards advertising the quitline and the availability of free nicotine patches were sent to 77,527 smoker households between August and October 2005. One postcard emphasized the effectiveness of the nicotine patch, whereas the other contrasted the risks of smoking and patch use. Response was evaluated using geographically linked calls to the quitline 15 days before and after each mailing. The postcard campaign increased call volume by 36%, with no difference between the two postcard versions. Those who reported calling the quitline in response to a mailing were more likely to request nicotine patches (91% versus 82%, p < .001). Direct mail can be used to increase quitline call volume and should be one of the promotional tools used by quitlines.     

Making direct mail direct. Indian River Memorial Hospital reaches newcomers with an improved direct mail campaign

New residents moving into a community are prime targets for new physicians and new hospitals. It's the hospital's chance to make a great first impression and establish a long-term relationship. Indian River Memorial Hospital in Vero Beach, Fla., has some experience in that area. They share their direct-mail ideas with you.     

Two cases of Bacillus infection and immunodepression

Objective

Members of the genus Bacillus are Gram-positive bacilli, ubiquitous in the environment. When isolated in clinical practice, it is frequently considered as due to environmental contamination. Bacillus cereus is the most frequent species isolated in clinical practice, nevertheless other Bacillus spp. are sometimes isolated. Bacillus bacteremia is uncommon, the affected patients are severely ill and frequently immunocompromised with hematological malignancies.

Study design

Two cases of bloodstream infection due to Bacillus species rarely described before are described, one due to Bacillus macerans and the other to Bacillus pumilus. Both patients presented with severe bacteremia and were immunodepressed after recent chemotherapy. They died a few days after admission to our ICU.

Conclusion

The initial report of Bacillus spp. isolated in blood culture in oncohematological patients indicates a potentially severe infection.     

Exposure to culturable microorganisms in paper mills and presence of symptoms associated with infections

BACKGROUND: Previous studies of paper machine operators have to a large extent focused on endotoxins as a possible health hazard, but not culturable micro-organisms (MOs). METHODS: Based on exposure assessment in 11 paper mills workers exposed to culturable bio-aerosols were grouped in three exposure groups. 781 exposed and 285 unexposed workers completed a questionnaire that provided data pertaining to infections and associated symptoms. RESULTS: Concentrations of culturable bacteria in process waters varied in the range 10(4)-10(6) colony forming units (cfu)/ml, and in bio-aerosols concentrations varied typically in the range 10(4)-->10(5) cfu/m3. Operators exposed to bio-aerosols reported higher cumulative incidence of symptoms associated with infections compared to the reference population (ORs = 1.7-5.9), and the group of highest exposed workers reported higher cumulative incidence than the group of lowest exposed (ORs = 1.2-3.6). CONCLUSION: Exposure to bio-aerosols containing culturable MOs may induce symptoms associated with infections among operators in paper mills.     

Occupational exposure to cotton dust in cottonseed oil mills

Air samples were collected at breathing height in the hulling-separation department of a modern cottonseed oil mill in Uzbekistan. The average elutriated mass concentration measured by standard cotton dust samplers was 4.6 mg/m3, much lower than the average total dust concentration measured by stationary personal samplers, 12.49 mg/m3, and by personal samplers attached to workers, 14.53 mg/m3. Differences in readings among the vertical elutriators, stationary personal samplers, and roving personal samplers are attributed to the distinct sampling nature and dynamics of these samplers. The data suggest that most of the dust consisted of particles larger than 15 microm, the particle size cutoff of the vertical elutriator. Differences in readings among stationary and roving personal samplers are statistically significant, presumably representing biased sampling by the roving personal samplers of regions characterized by high dust concentration (due to machines malfunctioning), the nonstatic nature of the sampling, and the interaction between the sampler and the worker (the personal cloud). Cotton dust concentrations in the hulling-separation room were nonuniform, peaking in front of and between the huller-separator pairs. The high total mass readings show that workers were exposed to very high levels of nonthoracic airborne dust, which upon inhalation tends to deposit in the extrathoracic airways. The high elutriated mass concentrations suggest that workers were exposed to respirable cotton dust at levels higher than 1 mg/m3 mean concentration, the current Occupational Safety and Health Administration (OSHA) Permissible Exposure Limit (PEL) for cotton dust. Regressions between dust concentrations measured by stationary vertical elutriators and by personal samplers attached to workers serve for estimating the potential occupational exposure to cotton dust of workers in the hulling-separation room.