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Ventilation standards, health, and indoor air quality have not been adequately examined for residential weatherization. This randomized trial showed how ASHRAE 62-1989 (n=39 houses) and ASHRAE 62.2-2010 (n=42 houses) influenced ventilation rates, moisture balance, indoor air quality, and self-reported physical and mental health outcomes. Average total airflow was nearly twice as high for ASHRAE 62.2-2010 (79 vs. 39 cfm). Volatile organic compounds, formaldehyde and carbon dioxide were all significantly reduced for the newer standard and first-floor radon was marginally lower, but for the older standard, only formaldehyde significantly decreased. Humidity in the ASHRAE 62.2-2010 group was only about half that of the ASHRAE 62-1989 group using the moisture balance metric. Radon was higher in the basement but lower on the first floor for ASHRAE 62.2-2010. Children in each group had fewer headaches, eczema, and skin allergies after weatherization and adults had improvements in psychological distress. Indoor air quality and health improve when weatherization is accompanied by an ASHRAE residential ventilation standard, and the 2010 ASHRAE standard has greater improvements in certain outcomes compared to the 1989 standard. Weatherization, home repair, and energy conservation projects should use the newer ASHRAE standard to improve indoor air quality and health. [ABSTRACT FROM AUTHOR]

Formaldehyde is a colorless, pungent gas commonly found in homes and is a respiratory irritant, sensitizer, carcinogen, and asthma trigger. Typical household sources include plywood and particleboard, cleaners, cosmetics, pesticides, and others. Development of a fast and simple measurement technique could facilitate continued research on this important chemical. The goal of this research is to apply an inexpensive short-term measurement method to find correlations between formaldehyde sources and concentration, and formaldehyde concentration and asthma control. Formaldehyde was measured using 30-min grab samples in length-of-stain detector tubes in homes ( n = 70) of asthmatics in the Boston, MA area. Clinical status and potential formaldehyde sources were determined. The geometric mean formaldehyde level was 35.1 ppb and ranged from 5 to 132 ppb. Based on one-way ANOVA, t-tests, and linear regression, predictors of log-transformed formaldehyde concentration included absolute humidity, season, and the presence of decorative laminates, fiberglass, or permanent press fabrics ( P < 0.05), as well as temperature and household cleaner use ( P < 0.10). The geometric mean formaldehyde concentration was 57% higher in homes of children with very poorly controlled asthma compared to homes of other asthmatic children ( P = 0.078). This study provides a simple method for measuring household formaldehyde and suggests that exposure is related to poorly controlled asthma. [ABSTRACT FROM AUTHOR]

The novel ectoparasiticide spinosad is a naturally occurring mixture of spinosyns A and D formed during a fermentation process. The spinosyns are tetracyclic macrolides with a unique ring system. Their mode of action differs from that of other commercially available insecticides. Laboratory and field trials were conducted to evaluate the use of spinosad in a chewable tablet at a dose range of 45 to 70 mg/kg for the treatment and control of flea infestations on dogs in Europe. Laboratory studies with artificially infested dogs confirmed persistent activity against Ctenocephalides felis of higher than 99 per cent at three weeks post-treatment with values of 96.5 to 97.8 per cent at four weeks. Two multicentric field trials with naturally infected client-owned animals in five European countries used selamectin as comparator. Monthly doses were given during the summer when many homes were heavily infested. Households with spinosad-treated dogs showed cumulative benefits with flea burdens reduced by about 97 per cent at 14 and 30 days and by 99.6 per cent at 60 and 90 days. Corresponding figures for selamectin were significantly lower (P<0.05) at all time points: between 88.5 and 91 per cent at 14 and 30 days, then 97.8 and 98.2 per cent at 60 and 90 days. Thus, the performance of spinosad compared favourably with that of the established reference product. [ABSTRACT FROM AUTHOR]

Although on-animal topical treatment with compounds such as imidacloprid has revolutionized the control of the cat flea, Ctenocephalides felis (Bouché) (Siphonaptera: Pulicidae), the development of insecticide resistance is a continuing threat. As part of a highly co-ordinated and unprecedented resistance monitoring programme for C. felis, 1437 flea isolates were collected by veterinary clinics in Australia, Germany, France, the U.K. and 29 states in the U.S.A. from 2002 to 2009. About 65% of the collections were made from June to October each year and 71% of the collections were from cats. Collections of flea eggs were sent to one of five different laboratories, where they were tested with a diagnostic dose of imidacloprid (3 p.p.m.) applied to larval flea-rearing medium. Of the 1437 collections received, 1064 contained adequate numbers of eggs for testing. Of these isolates, untreated eggs failed to hatch in 22.7% and were not considered valid bioassays. Survival rates >5% and development of adult fleas (a threshold for further testing) occurred in only 22 isolates. They were re-tested with the same diagnostic dose and none produced >5% adult emergence. Complete dose-response bioassays were performed on three of the isolates that had triggered a second test and produced slopes, intercepts and LC values similar to those for existing susceptible laboratory strains. Results confirmed sustained susceptibility of C. felis to imidacloprid, despite its widespread use for over a decade. [ABSTRACT FROM AUTHOR]

Abstract. To investigate the persistence of flea larvicidal activity in the immediate environment of cats treated with imidacloprid, eggs of the cat flea Ctenocephalides felis felis Bouché (Siphonaptera: Pulicidae), from untreated donor cats, were incubated on samples of fleece blanket taken from the floor of cages used by treated or untreated cats for a total of 10 or 20 6-h periods over 2–4 weeks, respectively. Sufficient imidacloprid accumulated during these periods to reduce the emergence of adult fleas by 94.7–97.6% when the blankets were tested after 18 weeks' storage at room temperature. A typical laundry procedure (washing with detergent at 50°C and low temperature tumble drying) removed this biological activity. Unwashed control blankets did not support the flea life-cycle as effectively as washed blankets or a sand substrate. [ABSTRACT FROM AUTHOR]

SummaryControl strategies were evaluated over a 6-month period in a home simulation model comprising a series of similar carpeted pens, housing matched groups of six cats, in which the life-cycle of the flea Ctenocephalides felis felis Bouché (Siphonaptera: Pulicidae) had been established. Additional adult fleas were placed on the cats at intervals to mimic acquisition of extraneous fleas from outside the home. Treatment strategies included a single subcutaneous deposition of injectable lufenuron supported by initial treatments with a short-acting insecticidal spray, or monthly topical applications of imidacloprid or fipronil. An untreated control group indicated that conditions were suitable for flea replication and development. Controls had to be combed on 18 occasions to remove excessive flea burdens and two developed allergic reactions. Lufenuron cats were combed once and required two insecticidal treatments in the first month to achieve control. Even so, small flea burdens were constantly present thereafter. Imidacloprid and fipronil treatments appeared to give virtually complete control throughout. Single fleas were found on imidacloprid cats on two occasions, whereas none were recovered from fipronil cats at any time after the first treatment. Tracer cats were used to monitor re-infestation rates at the end of the trial period. Small numbers of host-seeking fleas were demonstrated in all treatment pens, indicating that total eradication had not been accomplished. It is concluded that the home environment simulation model incorporating tracer animals could provide a powerful tool for studying flea population dynamics under controlled conditions but improved techniques are needed for quantifying other off-host life-cycle stages. [ABSTRACT FROM AUTHOR]

Each of 10 set-stocked calves was given a fenbendazole sustained- release intraruminal bolus at turnout for the control of parasitic bronchitis while a group of 10 similar calves was left untreated. The respiratory rates of the control calves were not greatly increased during the grazing season, but persistent coughing was evident from early July when they all had patent lungworm infections. Only occasional coughing was reported from the bolus-treated calves except for a transient increase in its frequency in late September. In mid-August, one of the treated calves was passing lungworm larvae and when they were housed six of the 10 had patent infections. In August tracer calves picked up an average of 23.5 lungworms per day from the control paddock but only 2.1 from the paddock grazed by the treated calves. In September the corresponding figures were 7.6 and 19.2 lungworms per day, respectively, from the control and ‘treated’ paddocks. After housing, the post mortem worm counts after an experimental challenge with larvae were reduced by 99.2 and 98.7 per cent (P<0.0001), respectively, for the control and bolus-treated calves in comparison with weight-matched parasite-naive calves. Thus, despite a relatively low level of challenge during the grazing season, the treated animals had developed a considerable degree of protective immunity. [ABSTRACT FROM PUBLISHER]

Abstract. As the ferret, Mustela putorius furo L. (Carnivora: Mustelidae), is becoming increasingly popular as a pet animal and as it is susceptible to the cat-flea, Ctenocephalides felis felis Bouché (Siphonaptera: Pulicidae), an experimental model was established for evaluating insecticidal treatments on this host. A high establishment rate (76.7–91.8%) was recorded when 60 unfed adult C. felis were placed on ferrets. This provided an adequate infestation for chemotherapeutic evaluation without causing undue discomfort to the host. Twelve ferrets were allocated to two groups matched for sex and individual ability to sustain a flea population. One group was treated topically with an imidacloprid spot-on formulation at a dose rate of 10 mg/kg body-weight on Day 0. All ferrets were infested with C. felis on Days - 1, 7, 14, 21 and 28, and flea counts were performed 8 and 24 h post-treatment and one day after each subsequent infestation. Fleas were removed at all but the 8 h count (when they were returned to their host). Flea burdens were reduced by 95.3% (P < 0.001) within 8 h of treatment and 100% efficacy was recorded at 24 h. At 1, 2, 3 and 4 weeks post-treatment, protection against re-infestation was 92.9% (P < 0.001), 55.7% (P < 0.02), 18.3% (NS) and 7.4% (NS), respectively. Thus, at this dose rate, imidacloprid gave excellent efficacy against a resident C. felis population and provided a high level of residual activity for at least one week after treatment. [ABSTRACT FROM AUTHOR]

Pyriproxyfen is a new insect growth regulator with potent activity against developing stages of the cat flea, . To determine its duration of action after application as a spot-on topical treatment, 20 cats were allocated to two groups. One group acted as untreated controls, and each cat in the other was given a single dose of 1 mg/kg pyriproxyfen. Each cat was infected with fleas at weekly intervals and caged. Eggs were collected and their viability determined as a measure of the effect of the agent on adult fleas. The effect of the transfer of pyriproxyfen from each cat to its immediate surroundings was monitored by observing the development of fertile flea eggs placed on samples of blanket taken from each cage. Results from untreated control cats showed that the experimental conditions were favourable for the lifecycle of the flea. Flea reproduction on treated cats was inhibited completely for seven weeks and substantially for at least a further two weeks. Blankets used by cats treated up to two weeks previously prevented flea development entirely and substantial control was still achieved up to four weeks after treatment. [ABSTRACT FROM PUBLISHER]

Four groups of six cats were kept in carpeted pens similarly infected with . One group was left untreated, but the other groups were treated every 28th day with either an insecticide (fenthion at 30 mg); or an inhibitor of insect development (lufenuron at 133 or 266 mg) or with both. A sudden upsurge in the numbers of fleas occurred on the control cats after 50 days. At this time, the three control strategies had reduced the counts by 91.3, 72.5 and 98.6 per cent, respectively. Thereafter, welfare considerations demanded the limitation of the flea burden on the control cats, but conditions were shown to be favourable for flea development throughout the study. The mean numbers of fleas on the treated groups after six months were 1.2, 11.0 and 0.4, respectively. After this, in addition to the fleas acquired in the pen, the cats were each infected weekly with five fleas to mimic roaming animals introducing extraneous fleas into the home. This produced no obvious effect on the counts and the mean values three months later were 0.5, 11.0 and 0.2, respectively. None of the strategies eradicated the flea population but they all reduced the numbers considerably and worked equally well whether or not small numbers of new fleas were introduced into the system. Significantly lower flea counts were maintained in the early and later stages of the study by the strategies including the insecticide. [ABSTRACT FROM PUBLISHER]

The article reports on the study which seeks to estimate the extent of the toxocaral soil contamination of children's play areas in Southern England. Toxocara species are most common ascaroid nematodes of dogs, foxes and cats which infect human through the feces of their host. Samples of topsoils collected from 24 sites in Southern England between June 19 to July 7, 2006 are studied. The study showed that there is a continuing presence of small numbers of Toxocara species in the area.

Three groups of six cats were kept in similar carpeted pens in which a self-replicating population of had been established. One group was left untreated, but the other groups were treated every 28th day with 0.5 ml of a 10 per cent fipronil spot-on formulation, and the cats in one of the treated groups also wore a methoprene collar. No fleas were found on any of the treated cats, either during the first 13 weeks of the study, when heavy flea burdens were developing in the control pen, or over the next 11 weeks when a declining number of fleas was present on the control group. [ABSTRACT FROM PUBLISHER]