Modeling Interventions in the Owned Cat Population to Decrease Numbers, Knox County, TN.

To find management strategies for controlling the owned cat population in Knox County, TN, the authors formulated a mathematical model using biological properties of such nonhuman animals and spay actions on certain age classes. They constructed this discrete-time model to predict the future owned cat population in this county and to evaluate intervention strategies to surgically sterilize some proportion of the population. Using the predicted population size and the number of surgeries for specific scenarios, they showed that focusing on specific age classes can be an effective feature in spay programs.

RABIES SURVEILLANCE AMONG BATS IN TENNESSEE, USA, 1996-2010.

Rabies virus (RABV) infects multiple bat species in the Americas, and enzootic foci perpetuate in bats principally via intraspecific transmission. In recent years, bats have been implicated in over 90% of human rabies cases in the US. In Tennessee, two human cases of rabies have occurred since 1960: one case in 1994 associated with a tricolored bat (Perimyotis subflavus) RABV variant and another in 2002 associated with the tricolored/silver-haired bat (P. subflavus/Lasionycteris noctivagans) RABV variant. From 1996 to 2010, 2,039 bats were submitted for rabies testing in Tennessee. Among 1,943 bats in satisfactory condition for testing and with a reported diagnostic result, 96% (1,870 of 1,943) were identified to species and 10% (196 of 1,943) were rabid. Big brown (Eptesicus fuscus), tricolored, and eastern red (Lasiurus borealis) bats comprised 77% of testable bat submissions and 84% of rabid bats. For species with five or more submissions during 1996-2010, the highest proportion of rabid bats occurred in hoary (Lasiurus cinereus; 46%), unspecified Myotis spp. (22%), and eastern red (17%) bats. The best model to predict rabid bats included month of submission, exposure history of submission, species, and sex of bat.

Baylisascaris procyonis in raccoons (Procyon lotor) in eastern Tennessee.

Raccoon (Procyon lotor) carcasses (n=118) were collected from July through December 2007 throughout eastern Tennessee. Necropsies were performed, and Baylisascaris procyonis was collected from the gastrointestinal tract of infected carcasses. Prevalence rates were determined for the overall sample population, males and females, and adults and juveniles. The sample population had a B. procyonis prevalence of 12.7%. Males and females had a prevalence of 15% and 11%, respectively; prevalence in adults and juvenile was 13% and 12.6%, respectively. There were no significant differences in prevalence rates between the different groups. Baylisascaris procyonis is an ascarid infection of raccoons that can infect humans and over 100 species of other animals. The presence of infection in raccoons, paired with the expansion of human populations in eastern Tennessee, is likely to lead to increased interactions between humans and raccoons and therefore an increased risk of human and domestic animal exposure to B. procyonis.

Estimating the time of death in domestic canines.

Because 36.1% of U.S. households have dogs, the time of death (TOD) of dogs at crime scenes can be useful to forensic investigators. However, there are few published studies based on postmortem changes in dogs. This study, conducted indoors in still air at approximately room temperature, monitored the postmortem reduction in rectal, liver, brain, and aural temperatures in 16 dogs for 32 h after death. Graphs of temperature reduction were prepared to estimate the TOD of dogs within the first 32 h postmortem. Sex, body mass, and hair coat density did not affect the rate of body temperature reduction, but increased body weight and volume slowed it. Rectal temperature was the most convenient, reasonable site for measuring body temperature. Vitreous humor potassium ion concentration [K(+)] was measured in both eyes at c. 1.5 and 7 h after death. Both eyes had the same [K(+)] when measured simultaneously, and [K(+)] increased after death.

Birth and death rate estimates of cats and dogs in U.S. households and related factors.

Studies report variable factors associated with dog and cat surpluses in the United States. Estimates of cat and dog birth and death rates help understand the problem. This study collected data through a commercial survey company, distributing questionnaires to 7,399 cat- and dog-owning households (HHs) in 1996. The study used an unequal probability sampling plan and reported estimates of means and variances as weighted averages. The study used estimates of HHs and companion animals for national projections. More than 9 million owned cats and dogs died during 1996-yielding crude death rates of 8.3 cat deaths/100 cats in HHs and 7.9 dog deaths/100 dogs in HHs. The study reported twice as many kitten as puppy litters, with an average litter size of 5.73 and 7.57, respectively. The study reported data on planned versus unplanned litters, reasons caregivers did not spay females, disposition of litters, and sources of animals added to HHs. These first national estimates indicate the magnitude of, and reasons for, animals leaving HHs. The crude birth rate was estimated to be 11.2 kittens/100 cats in HHs and 11.4 puppies/100 dogs in HHs.

Prevalence of endoparasitic infection in children and its relation with cholera prevention efforts in Mexico.

OBJECTIVE: To investigate whether increased knowledge and use of public health measures promoted for cholera prevention is reflected in lower prevalence of parasitic infection in households in a community in the state of Tamaulipas, Mexico, that is close to the border with the United States of America. METHODS: Between 1994 and 1997, fecal samples from 438 children were collected through convenience sampling and then examined for helminth eggs/larvae and protozoan cysts as biologic indicators of household compliance with recommended cholera prevention measures. The suggested measures were to wash hands before meals and after defecation, to drink purified water, to wash fruits and vegetables, and to eat well-cooked food. In addition, information on the knowledge of and the use of cholera preventive measures was collected by interviews with adult informants in 252 households (186 of those households also provided a fecal sample for analysis). RESULTS: Parasitic infections occurred in 131 of the 438 children (30%), who resided in 79 of the 186 households (42%) that provided fecal samples. Giardia lamblia accounted for 12.5% of all infections. Infections with Hymenolepis nana, Ascaris lumbricoides, Trichuris trichiura, Enterobius vermicularis, Ancylostoma/Necator, Strongyloides stercoralis, Entamoeba coli, Entamoeba hartmanni, Entamoeba histolytica, Endolimax nana, and Iodamoeba bütschlii were also noted. Infected children were older and more often had an infected sibling. Households with three or more children were also more likely to have an infected child. The primary caregivers in the households where at least one child had a parasitic infection were distinguished by their inability to list at least three cholera prevention measures from memory. CONCLUSIONS: The 42% household prevalence of parasitic infection was relatively high and indicates that some residents of this community may not have fully embraced the public health education efforts promoted for prevention of cholera. The occurrence of nonpathogenic protozoan parasites such as Endolimax nana, Entamoeba coli, Entamoeba hartmanni, and I. bütschlii are important bioindicators for the persistence of unhygienic behaviors that increase the risk of cholera and other infectious diseases dependent on fecal-oral transmission. Information obtained by similar studies can be useful for monitoring compliance with community health and hygiene programs and may indicate the need to intensify educational efforts for the prevention of diarrhea associated with enteric pathogens that cannot be controlled by drugs alone.

Prevalence of endoparasitic infection in children and its relation with cholera prevention efforts in Mexico

OBJECTIVE: To investigate whether increased knowledge and use of public health measures promoted for cholera prevention is reflected in lower prevalence of parasitic infection in households in a community in the state of Tamaulipas, Mexico, that is close to the border with the United States of America. METHODS: Between 1994 and 1997, fecal samples from 438 children were collected through convenience sampling and then examined for helminth eggs/larvae and protozoan cysts as biologic indicators of household compliance with recommended cholera prevention measures. The suggested measures were to wash hands before meals and after defecation, to drink purified water, to wash fruits and vegetables, and to eat well-cooked food. In addition, information on the knowledge of and the use of cholera preventive measures was collected by interviews with adult informants in 252 households (186 of those households also provided a fecal sample for analysis). RESULTS: Parasitic infections occurred in 131 of the 438 children (30 percent), who resided in 79 of the 186 households (42 percent) that provided fecal samples. Giardia lamblia accounted for 12.5 percent of all infections. Infections with Hymenolepis nana, Ascaris lumbricoides, Trichuris trichiura, Enterobius vermicularis, Ancylostoma/Necator, Strongyloides stercoralis, Entamoeba coli, Entamoeba hartmanni, Entamoeba histolytica, Endolimax nana, and Iodamoeba bütschlii were also noted. Infected children were older and more often had an infected sibling. Households with three or more children were also more likely to have an infected child. The primary caregivers in the households where at least one child had a parasitic infection were distinguished by their inability to list at least three cholera prevention measures from memory. CONCLUSIONS: The 42 percent household prevalence of parasitic infection was relatively high and indicates that some residents of this community may not have fully embraced the public health education efforts promoted for prevention of cholera. The occurrence of nonpathogenic protozoan parasites such as Endolimax nana, Entamoeba coli, Entamoeba hartmanni, and I. bütschlii are important bioindicators for the persistence of unhygienic behaviors that increase the risk of cholera and other infectious diseases dependent on fecal-oral transmission...