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Epidemiological surveillance systems for pathogens in wild species have been proposed as a preventive measure for epidemic events. These systems can minimize the detrimental effects of an outbreak, but most importantly, passive surveillance systems are the best adapted to countries with limited resources. Therefore, this research aimed to evaluate the technical and infrastructural feasibility of establishing this type of scheme in Costa Rica by implementing a pilot program targeting the detection of pathogens of zoonotic and conservation importance in wildlife. Between 2018 and 2020, 85 carcasses of free-ranging vertebrates were admitted for post-mortem and microbiology analysis. However, we encountered obstacles mainly related to the initial identification of cases and limited local logistics capacity. Nevertheless, this epidemiological surveillance scheme allowed us to estimate the general state of health of the country's wildlife by establishing the causes of death according to pathological findings. For instance, 60% (51/85) of the deaths were not directly associated with an infectious agent. Though in 37.6% (32/85) of these cases an infectious agent associated or not with disease was detected. In 27.1% (23/85) of the cases, death was directly related to infectious agents. Furthermore, 12.9% (11/85), the cause of death was not determined. Likewise, this wildlife health monitoring program allowed the detection of relevant pathogens such as Canine Distemper Virus, Klebsiella pneumoniae, Angiostrongylus spp., Baylisascaris spp., among others. Our research demonstrated that this passive surveillance scheme is cost-effective and feasible in countries with limited resources. This passive surveillance can be adapted to the infrastructure dedicated to monitoring diseases in productive animals according to the scope and objectives of monitoring wildlife specific to each region. The information generated from the experience of the initial establishment of a WHMP is critical to meeting the challenges involved in developing this type of scheme in regions with limited resources and established as hotspots for emerging infectious diseases., Competing Interests: The authors have declared that no competing interest exist.

Eastern equine encephalitis and Venezuelan equine encephalitis are endemic neglected tropical diseases in the Americas, causing encephalitis in both horses and humans. In 2013, a cross-sectional study was performed in 243 horses located in the highlands and lowlands throughout Costa Rica. Serum samples were analyzed with an IgG ELISA and confirmed by the plaque-reduction neutralization test (PRNT80). Venezuelan equine encephalitis virus (VEEV) and Eastern equine encephalitis virus (EEEV) overall seroprevalences by the PRNT80 were 36% (95% confidence interval [CI]: 29.9-42.5; 78/217 horses) and 3% (95% CI: 1.3-5.9; 6/217 horses), respectively. Both the viruses occurred in the lowlands and highlands. Rainfall and altitude were associated with VEEV seropositivity in the univariate analysis, but only altitude <100 meters above sea level was considered a risk factor in the multivariate analysis. No risk factors could be identified for the EEEV in the multivariate analysis. This is the first study that estimates the seroprevalence of the EEEV and VEEV in Costa Rican horses. The VEEV is widely distributed, whereas the EEEV occurs at a much lower frequency and only in specific areas. Clinical cases and occasional outbreaks of both viruses are to be expected., (Copyright © 2020 The Author(s). Published by Elsevier Inc. All rights reserved.)

Leptospirosis and rabies are zoonotic diseases of public health importance and endemic diseases in tropical countries such as Costa Rica. Peridomestic wild animals such as raccoons ( Procyon lotor) have been implicated as competent hosts of Leptospira spirochetes and rabies virus. This study focused on understanding the role of urban raccoons in the dynamics of leptospirosis and rabies in a tropical environment. A total of 97 specimens of the common raccoon were captured within the Greater Metropolitan Area of Costa Rica; 32.6% (31/95) of raccoons presented evidence of antibodies (> 1: 100) against Leptospira sp. Attempts to cultivate Leptospira failed, but 19 serovars were identified, which are also responsible for causing disease in humans in Costa Rica. Detected titers ranged from 1: 100 to 1: 6400. Lymphoid hyperplasia in kidneys and spirochetes were demonstrated in 3 of 20 necropsied cases (15%). Twenty brain samples were analyzed by hematoxylin and eosin stain for evidence of encephalitis and Negri body detection and simultaneously frozen brain material was employed to perform a rapid immunoassay test for rabies antigen. All tested samples were negative. This study is the first report of Leptospira seroprevalence in raccoons that cohabit urban areas in Costa Rica. We also highlight the importance of the raccoon as one of their natural competent host and sentinel animals within highly populated urban environments in tropical cities.

Wild animals are involved in zoonotic disease transmission cycles. These are generally complex and poorly understood, especially among animals adapted to life in human ecosystems. Raccoons are reservoirs and effective carriers for infectious agents such as Salmonella throughout different environments and contribute to the transference of resistance genes. This study examined the presence of circulating Salmonella sp. in a population of raccoons in a tropical urban environment and evaluated resistance to antibiotics commonly used to treat salmonellosis. A total of 97 raccoons of different ages and sex were included in this study. 49% (38-60 CI) of the faecal samples were positive for Salmonella spp. The study identified 15 circulating serovars with the most prevalent being S. Hartford (7/15), S. Typhimurium (4/15) and S. Bovismorbificans (4/15). These serovars correspond to the serovars detected in humans with clinical symptoms in Costa Rica. 9.5% of the Salmonella strains recovered demonstrated ciprofloxacin resistance, and 7.1% showed resistance to nalidixic acid. This study provides evidence of multiple Salmonella serovars circulating in a population of urban raccoons in Costa Rica. Furthermore, the study confirms the existence of antimicrobial resistance to two antibiotics used to treat human salmonellosis. The findings emphasize the role of the raccoon as a reservoir of Salmonella in the Greater Metropolitan Area of Costa Rica (GAM) and stress the need for active monitoring of the presence and possible spread in antibiotic resistance due to this peri-domestic carnivore., (© 2019 The Authors. Zoonoses and Public Health published by Blackwell Verlag GmbH.)

Ferlaviruses (FV, previously referred to as ophidian paramyxoviruses, OPMV), are enveloped viruses with a negative-strand RNA genome, affecting snakes in captivity worldwide. Infection is characterized by respiratory and nervous clinical signs and carries high mortality rates, but no specific treatment or vaccine is currently available. Costa Rica has 16 species of vipers, found in captivity in collections essential for antivenom production, reintroduction, and public education. FV circulation in these populations was previously unknown, and the risk of introducing the viruses into naïve collections or free-ranging populations exists if the virus's presence is confirmed. The objective of this study was to determine seroprevalence and FV shedding in 150 samples from captive vipers in nine collections across Costa Rica. A hemagglutination inhibition (HI) assay was performed to determine the antibody titer against two Ferlavirus strains, Bush viper virus (BV) and Neotropical virus (NT), and reverse-transcriptase polymerase chain reaction (RT-PCR) and sequencing to determine virus secretion in cloacal swabs. Ferlavirus strains were replicated in Vero cells, and chicken anti-FV polyclonal antibodies were produced and used as a positive control serum for the HI. Results demonstrate that seroprevalence of anti-FV antibodies in viper serum was 26.6% (n = 40) for the BV strain and 30% (n = 45) for the NT strain in the population tested. Furthermore, molecular characterization of FV group A was possible by sequencing the virus recovered from three cloacal swabs, demonstrating circulation of FV in one collection. This study demonstrates for the first time serological evidence of FV exposure and infection in vipers in captivity in Costa Rica, and suggests cross reactivity between antibodies against both strains. Appropriate biosafety measures could prevent the spread of FV between and within collections of reptiles in the country.

The Asian tiger mosquito, Aedes albopictus (Skuse) (Diptera: Culicidae), is a vector of several human pathogens. Ae. albopictus is also an invasive species that, over recent years, has expanded its range out of its native Asia. Ae. albopictus was suspected to be present in Central America since the 1990s, and its presence was confirmed by most Central American nations by 2010. Recently, this species has been regularly found, yet in low numbers, in limited areas of Panamá and Costa Rica (CR). Here, we report that short sequences (∼558 bp) of the mitochondrial cytochrome oxidase subunit 1 (COI) and NADH dehydrogenase subunit 5 genes of Ae. albopictus, had no haplotype diversity. Instead, there was a common haplotype for each gene in both CR and Panamá. In contrast, a long COI sequence (∼1,390 bp) revealed that haplotype diversity (±SD) was relatively high in CR (0.72±0.04) when compared with Panamá (0.33±0.13), below the global estimate for reported samples (0.89±0.01). The long COI sequence allowed us to identify seven (five new) haplotypes in CR and two (one new) in Panamá. A haplotype network for the long COI gene sequence showed that samples from CR and Panamá belong to a single large group. The long COI gene sequences suggest that haplotypes in Panamá and CR, although similar to each other, had a significant geographic differentiation (Kst=1.33; P<0.001). Thus, most of our results suggest a recent range expansion in CR and Panamá., (© The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.)

Chromobacterium violaceum is a gram-negative saprobe bacterium that is a rare opportunistic pathogen in mammals. There are numerous reports in humans including fatalities, but no record exists in free-ranging nonhuman primates. Here we report an infection by C. violaceum in a wild adult male howler monkey (Alouatta palliata) captured at Ballena Marine National Park, in southwestern Costa Rica. The individual had severe skin lesions over its extremities; gross findings included multiple skin ulcers, white foci in liver, and lymphoid hyperplasia. Histologic results included deep dermatitis with presence of necrotic epithelial cells where clusters of coccoid-shaped bacteria were detected. In the liver, numerous neutrophils forming microabscesses, telangiectasia, and focal necrotic areas were observed. Necrotic liver tissue sampled for bacteriologic culture resulted in the isolation of C. violaceum. We could not ascertain the source or mechanism of infection in this case, although infection through skin microabrasions is suspected. To the best of our knowledge, this is the first report for this pathogen in a wild, nonhuman primate. This report also draws attention to this infectious agent as a potential emerging wildlife disease and consideration should be paid by regional veterinary and epidemiologic vigilance services.

Sloths may serve as host to a wide range of parasites. However, there is little information available on the types of parasites that affect Costa Rica's sloth population. During a 1-yr period, 65 specimens of Costa Rican sloth species (Choloepus hoffmanni; n = 56) and Bradypus variegates; n = 9) from a local zoo were sampled. Fecal samples were evaluated using two different diagnostic techniques, Sheather's flotation and sedimentation. Concurrently, these sloths were examined for ectoparasites. Gastrointestinal parasites were found in 14 sloths (21.5%), from which 13 animals were C. hoffmanni and one was B. variegatus. Gastrointestinal parasites were recognized as Coccidia 71.4% (10/14), Cestoda 21.4% (3/14), and Spiruroidea 7.1% (1/14). Coccidia and cestodes were seen in C. hoffmanni, and spirurids were identified in B. variegatus. Among 27 sloths examined, only six had dermal problems (five C. hoffmanni and two B. variegatus). Ectoparasites recovered were Sarcoptes scabiei (Acari, Sarcoptidae) mites and Amblyomma varium (Acari, Ixodidae) ticks. This is the first time that cestode strobilae and nematode eggs are reported in sloth feces and that Monezia benedeni and L. leptocephalus were found in captive sloths.