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Journal: Vector borne and zoonotic diseases (Larchmont, N.Y.)


Educational interventions to reduce Lyme disease (LD) among at-risk school children have had little study. The purpose of this study was to evaluate whether a short in-class LD education program based on social learning theory and the Health Belief Model (HBM) impacted a child’s knowledge, attitude, and preventive behavior.

Concepts: Psychology, Truth, Education, Educational psychology, Model theory, Learning, School, History of education


This is the first comprehensive epidemiological analysis of rabies in Costa Rica. We characterized the occurrence of the disease and demonstrated its endemic nature in this country. In Costa Rica, as in other countries in Latin America, hematophagous vampire bats are the primary wildlife vectors transmitting the rabies virus to cattle herds. Between 1985 and 2014, a total of 78 outbreaks of bovine rabies was reported in Costa Rica, with documented cases of 723 dead cattle. Of cattle outbreaks, 82% occurred between 0 and 500 meters above sea level, and seasonality could be demonstrated on the Pacific side of the country, with significantly more outbreaks occurring during the wet season. A total of 1588 animal samples, or an average of 55 samples per year, was received by the veterinary authority (SENASA) for rabies diagnostic testing at this time. Of all samples tested, 9% (143/1588) were positive. Of these, 85.6% (125/1588) were from cattle; four dogs (0.3% [4/1588]) were diagnosed with rabies in this 30-year period. Simultaneously, an extremely low number (n = 3) of autochthonous rabies cases were reported among human patients, all of which were fatal. However, given the virus' zoonotic characteristics and predominantly fatal outcome among both cattle and humans, it is extremely important for healthcare practitioners and veterinarians to be aware of the importance of adequate wound hygiene and postexpositional rabies prophylaxis when dealing with both wild and domestic animal bites.

Concepts: Epidemiology, Spanish language, Veterinary medicine, Bat, Rabies, Latin America, Nicaragua, Costa Rica


Problem: The emergence of novel coronavirus (SARS-CoV-2) in Wuhan, China, in November 2019 and a growing body of information compel inquiry regarding the transmissibility of infection between humans and certain animal species. Although there are a number of issues to be considered, the following points are most urgent: The potential for domesticated (companion) animals to serve as a reservoir of infection contributing to continued human-to-human disease, infectivity, and community spread. The ramifications to food security, economy, and trade issues should coronavirus establish itself within livestock and poultry. The disruption to national security if SARS-CoV-2 and its fairly well-established effects on smell (hyposmia/anosmia) to critical military service animals including explosive detector dog, narcotics detector dog, specialized search dog, combat tracker dog, mine detection dog, tactical explosive detector dog, improvised explosive device detector dog, patrol explosive detector dog, and patrol narcotics detector dog, as well as multipurpose canines used by special operations such as used by the U.S. customs and border protection agency (e.g., Beagle Brigade). This article presents in chronological order data that both individually (as received independently from multiple countries) and collectively urge studies that elucidate the following questions. 1.What animal species can be infected with SARS-CoV-2, the likely sources of infection, the period of infectivity, and transmissibility between these animals and to other animal species and humans? 2.What are the best diagnostic tests currently available for companion animals and livestock? 3.What expressions of illness in companion and other animal species can serve as disease markers? Although it is recognized that robust funding and methodology need to be identified to apply the best scientific investigation into these issues, there may be easily identifiable opportunities to capture information that can guide decision and study. First, it may be possible to quickly initiate a data collection strategy using in-place animal gatekeepers, such as zookeepers, veterinarians, kennel owners, feed lots, and military animal handlers. If provided a simple surveillance form, their detection of symptoms (lethargy, hyposmia, anosmia, and others) might be quickly reported to a central data collection site if one were created. Second, although current human COVID-19 disease is aligning around areas of population density and cluster events, it might be possible to overlay animal species density or veterinary reports that could signal some disease association in animals with COVID-19 patients. Unfortunately, although companion animals and zoo species have repeatedly served as sentinels for emerging infectious diseases, they do not currently fall under the jurisdiction of any federal agency and are not under surveillance.


Abstract Urban Norway and black rats (Rattus norvegicus and Rattus rattus) are the source of a number of pathogens responsible for significant human morbidity and mortality in cities around the world. These pathogens include zoonotic bacteria (Leptospira interrogans, Yersina pestis, Rickettsia typhi, Bartonella spp., Streptobacillus moniliformis), viruses (Seoul hantavirus), and parasites (Angiostrongylus cantonensis). A more complete understanding of the ecology of these pathogens in people and rats is critical for determining the public health risks associated with urban rats and for developing strategies to monitor and mitigate those risks. Although the ecology of rat-associated zoonoses is complex, due to the multiple ways in which rats, people, pathogens, vectors, and the environment may interact, common determinants of human disease can still be identified. This review summarizes the ecology of zoonoses associated with urban rats with a view to identifying similarities, critical differences, and avenues for further study.

Concepts: Epidemiology, Bacteria, Microbiology, Rat, Yersinia pestis, Brown rat, Zoonosis, Old World rats and mice


Recent reports of Zika virus (ZIKV) isolates from Culex species mosquitoes have resulted in concern regarding a lack of knowledge on the number of competent vector species for ZIKV transmission in the new world. Although observations in the field have demonstrated that ZIKV isolation can be made from Culex species mosquitoes, the detection of ZIKV in these mosquitoes is not proof of their involvement in a ZIKV transmission cycle. Detection may be due to recent feeding on a viremic vertebrate, and is not indicative of replication in the mosquito. In this study, susceptibility of recently colonized Culex species mosquitoes was investigated. The results showed a high degree of refractoriness among members of Culex pipiens complex to ZIKV even when exposed to high-titer bloodmeals. Our finding suggests that the likelihood of Culex species mosquitoes serving as secondary vectors for ZIKV is very low, and so that vector control strategies for ZIKV should remain focused on Aedes species mosquitoes. Our demonstration that Culex quinquefasciatus from Vero Beach, FL, is refractory to infection with ZIKV is especially important and timely. Based on our data, we would conclude that the autochthonous cases of Zika in Florida are not due to transmission by C. quinquefasciatus, and so control efforts should focus on other species, logically Aedes aegypti and Aedes albopictus.

Concepts: Mosquito, Yellow fever, Aedes aegypti, Aedes, Dengue fever, Culicidae, Pest insects, Culex


Abstract Salmonella enterica is a pathogen with a wide host-range that presents great concern in developed and developing countries. To determine and characterize Salmonella strains found in Chile’s waterfowl, we sampled 758 birds along 2000 km of the Chilean coast. In this sample, 46 isolates from 10 serotypes were detected, several with multidrug resistance phenotypes and different combinations of virulence-associated genes (virulotypes). These results suggest that Salmonella infection in waterfowl in Chile could have impacts on public and animal health.

Concepts: Gene, Bacteria, Evolution, Microbiology, Salmonella enterica, Salmonella, Chile, 1984 Rajneeshee bioterror attack


Abstract Wild species are essential hosts for maintaining Ixodes ticks and the tick-borne diseases. The aim of our study was to estimate the prevalence, the rate of co-infection with Babesia, Bartonella, and Anaplasma phagocytophilum, and the molecular diversity of tick-borne pathogens in roe deer in Poland. Almost half of the tested samples provided evidence of infection with at least 1 species. A. phagocytophilum (37.3%) was the most common and Bartonella (13.4%) the rarest infection. A total of 18.3% of all positive samples from roe deer were infected with at least 2 pathogens, and one-third of those were co-infected with A. phagocytophilum, Bartonella, and Babesia species. On the basis of multilocus molecular studies we conclude that: (1) Two different genetic variants of A. phagocytophilum, zoonotic and nonzoonotic, are widely distributed in Polish roe deer population; (2) the roe deer is the host for zoonotic Babesia (Bab. venatorum, Bab. divergens), closely related or identical with strains/species found in humans; (3) our Bab. capreoli and Bab. divergens isolates differed from reported genotypes at 2 conserved base positions, i.e., positions 631 and 663; and (4) this is the first description of Bart. schoenbuchensis infections in roe deer in Poland. We present 1 of the first complex epidemiological studies on the prevalence of Babesia, Bartonella, and A. phagocytophilum in naturally infected populations of roe deer. These game animals clearly have an important role as reservoir hosts of tick-borne pathogens, but the pathogenicity and zoonotic potential of the parasite genotypes hosted by roe deer requires further detailed investigation.

Concepts: Genetics, Epidemiology, Disease, Biology, Infection, Deer, Lyme disease, Tick


The recent emergence of the mosquito-borne Zika virus (ZIKV) in the Americas has become a global public health concern. We describe a series of experimental infections designed to investigate whether animals within certain taxonomic groups in North America have the potential to serve as ZIKV amplifying or maintenance hosts. Species investigated included armadillos, cottontail rabbits, goats, mink, chickens, pigeons, ground hogs, deer mice, cattle, raccoons, ducks, Syrian Golden hamsters, garter snakes, leopard frogs, house sparrows, and pigs. Infectious virus was isolated from blood only in frogs and armadillos; however, the magnitude of viremia was low. In addition, neutralizing antibodies were detected after infection in goats, rabbits, ducks, frogs, and pigs. This study indicates that the animals tested to date are unlikely to act as animal reservoirs for ZIKV, but that rabbits and pigs could potentially serve as sentinel species. Understanding the transmission cycle and maintenance of ZIKV in animals will help in developing effective surveillance programs and preventative measures for future outbreaks.

Concepts: Infection, United States, Bird, Transmission and infection of H5N1, Mammal, North America, Americas, Latin America


During the last decades, large tularemia outbreaks in humans have coincided in time and space with population outbreaks of common voles in northwestern Spain, leading us to hypothesize that this rodent species acts as a key spillover agent of Francisella tularensis in the region. Here, we evaluate for the first time a potential link between irruptive vole numbers and human tularemia outbreaks in Spain. We compiled vole abundance estimates obtained through live-trapping monitoring studies and official reports of human tularemia cases during the period 1997-2014. We confirm a significant positive association between yearly cases of tularemia infection in humans and vole abundance. High vole densities during outbreaks (up to 1000 voles/hectare) may therefore enhance disease transmission and spillover contamination in the environment. If this ecological link is further confirmed, the apparent multiannual cyclicity of common vole outbreaks might provide a basis for forecasting the risk of tularemia outbreaks in northwestern Spain.

Concepts: Time, Population ecology, Natural environment, Rodent, Francisella tularensis, Vole, Microtus, Common Vole


The sera from healthy individuals aged 10-59 years randomly selected from the general population during repeated cross-sectional surveys were stored at -20°C at the serum bank of the National Institute of Public Health in Prague. The sera included in the present study were collected in the 1980s and in 2001 in eight districts of the Czech Republic. The proportional representation of the study localities was similar in both periods. The sera were uniformly distributed in 5-year age groups for 10- to 19-year-olds and in 10-year age groups for 20- to 59-year-olds. Males and females were nearly equally represented in both periods. Altogether 704 sera, 434 from the period 1978-1989 and 270 from 2001, were screened for antibodies against tick-borne encephalitis virus (TBEV) by the virus neutralization test. The seroprevalence rates were 11.5% in the 1980s and 26.3% in 2001. From the logistic regression model, it follows that the chance of detecting anti-TBEV antibodies was more than twice higher in 2001 than in 1978-1989 (odds ratio [OR]=2.22). The differences between males and females were not statistically significant, nor was sex-period interaction. The time trends in the seropositivity rates were similar in all age groups, with the exception of the 10- to 14-year-olds (p=0.914). The rate of seropositives in the age group 15-59 years increased 1.9 times, whereas that in the age group 10-14 years rose 5.1 times. In areas comparable to those where the study sera were collected, the average incidence rates of tick-borne encephalitis (TBE) per 100,000 population aged 10-59 increased significantly from 3.35 in 1978-1989 to 8.96 in 2001 (p<0.001). The age-specific antibody trends in adult age groups in both periods suggest that clinically manifest or inapparent TBE cases do not induce lifelong immunity, but they are likely to reflect the previous epidemiological situation.

Concepts: Antibody, Regression analysis, Epidemiology, Statistics, Demography, Czech Republic, Encephalitis, Tick-borne encephalitis