Risk Of Zoonotic Disease Transmission Research Articles

Major zoonotic diseases of public health importance in Bangladesh

Zoonotic diseases cause repeated outbreaks in humans globally. The majority of emerging infections in humans are zoonotic. COVID‐19 is an ideal example of a recently identified emerging zoonotic disease, causing a global pandemic. Anthropogenic factors such as modernisation of agriculture and livestock farming, wildlife hunting, the destruction of wild animal habitats, mixing wild and domestic animals, wildlife trading, changing food habits and urbanisation could drive the emergence of zoonotic diseases in humans. Since 2001, Bangladesh has been reporting many emerging zoonotic disease outbreaks such as nipah, highly pathogenic avian influenza, pandemic H1N1, and COVID‐19. There are many other potential zoonotic pathogens such as Ebola, Middle East respiratory syndrome coronavirus, Kyasanur forest disease virus and Crimean–Congo haemorrhagic fever that may emerge in the future. However, we have a limited understanding of zoonotic diseases’ overall risk in humans and associated factors that drive the emergence of zoonotic pathogens. This narrative review summarised the major emerging, re‐emerging, neglected and other potential zoonotic diseases in Bangladesh and their associated risk factors. Nipah virus and Bacillus anthracis caused repeated outbreaks in humans. More than 300 human cases with Nipah virus infection were reported since the first outbreak in 2001. The highly pathogenic avian influenza virus (H5N1) caused more than 550 outbreaks in poultry, and eight human cases were reported so far since 2007. People of Bangladesh are frequently exposed to zoonotic pathogens due to close interaction with domestic and peri‐domestic animals. The rapidly changing intensified animal–human–ecosystem interfaces and risky practices increase the risk of zoonotic disease transmission. The narrative review's findings are useful to draw attention to the risk and emergence of zoonotic diseases to public health policymakers in Bangladesh and the application of one‐health approach to address this public health threat.

The merits of entomophagy in the post COVID-19 world

BackgroundIn 2020, human society underwent several drastic changes due to the coronavirus disease 2019 (COVID-19) pandemic, which generated an unprecedented global impact. Since the onset of the COVID-19 pandemic, various pressing concerns underlying food security, such as transport, production, and maintenance of the supply chain, have been raised. Scope and approachThe present study aimed to describe and review the merits of entomophagy in the post COVID-19 world, especially with regard to the low risk for zoonotic disease spread, high production rate, and future prospects for inducing entomophagy to enhance the diversity in the food system in comparison to conventional livestock. Key findings and conclusionsThe advantages of entomophagy in the post COVID-19 world have been elucidated herein, with particular emphasis on the minimal risk of zoonotic disease transmission and production efficiency, in addition to the future goal of establishment of entomophagy to expand redundancy and diversity in the food system as against the utility of conventional livestock. In the current scenario, as well as in the post COVID-19 situation, boosting entomophagy may play a pivotal role in global food security, as the aspects already touched upon have amply demonstrated.

Light Cross-Linkable Marine Collagen for Coaxial Printing of a 3D Model of Neuromuscular Junction Formation.

Collagen is a major component of the extracellular matrix (ECM) that modulates cell adhesion, growth, and migration, and has been utilised in tissue engineering applications. However, the common terrestrial sources of collagen carry the risk of zoonotic disease transmission and there are religious barriers to the use of bovine and porcine products in many cultures. Marine based collagens offer an attractive alternative and have so far been under-utilized for use as biomaterials for tissue engineering. Marine collagen can be extracted from fish waste products, therefore industry by-products offer an economical and environmentally sustainable source of collagen. In a handful of studies, marine collagen has successfully been methacrylated to form collagen methacrylate (ColMA). Our work included the extraction, characterization and methacrylation of Red Snapper collagen, optimisation of conditions for neural cell seeding and encapsulation using the unmodified collagen, thermally cross-linked, and the methacrylated collagen with UV-induced cross-linking. Finally, the 3D co-axial printing of neural and skeletal muscle cell cultures as a model for neuromuscular junction (NMJ) formation was investigated. Overall, the results of this study show great potential for a novel NMJ in vitro 3D bioprinted model that, with further development, could provide a low-cost, customizable, scalable and quick-to-print platform for drug screening and to study neuromuscular junction physiology and pathogenesis.

Elucidating the Biological Activity of Fish-Derived Collagen and Gelatine Hydrolysates using Animal Cell Culture - A Review

A large percentage of a fish's weight is generally discarded during fish processing. Reducing the waste products of marine origin is a subject of great interest within the scientific community. Pelagic byproducts, such as the structural protein collagen, which can be generated during the processing of fish, have been proposed as an alternative to terrestrial, mammalian sources due to advantages including high availability and low risk of zoonotic disease transmission. Gelatine has multiple possible applications, ranging from nutraceutical applications to cosmetics and has the advantage of being generally regarded as safe. In this multidisciplinary review, the chemistry of gelatine and its parent protein collagen, the chemical reactions to generate their hydrolysates, and studies on their biological activities using animal cell culture are discussed.

ANIMALS CAUSING INFECTIOUS DISEASE - A BRIEF REVIEW

Background: Zoonotic diseases are the infectious disease which is transmitted to people and vice versa. It is caused by all sorts of pathogens, including bacteria, rodents, fungi, viruses and prions. And though known for hundreds of years, the public health effect has risen in recent decades as a result of the effective combination of vaccination and efficient care to minimize the spread of human infectious diseases and the development of new zoonotic diseases.
 Objectives: To systematically review and describe the causes of infections.
 Methods: We searched Google search engine, Pubmed and other databases on the internet for the articles on topics related to infectious disease due to animals and zoonotic diseases. We searched reference lists of all primary and review articles based on the key words “zoonotic diseases, animals, infectious disease, spill over, pandemic etc.,” Data regarding zoonotic diseases was collected, summarized and analysed.
 Results: This review analyse what are all the possible ways the animals causing the infectious disease to the people and how to prevent from the infection.
 Conclusion: By strict use of personal protection and some precautious methods are used to prevent the transmission of infection. The advantages of pets far outweigh their fear of zoonotic infections cannot be absolutely prevented by people with animals. It is also their responsibility to provide the required training to provide the healthy use of animals and reduce the risk of zoonotic disease transmission for veterinarians, physicians and public health staff.
 Keywords: Animals, Infectious disease, Transmission, People , Pets, Personal protection.

Evaluation of Risk of Zoonotic Pathogen Transmission in a University-Based Animal Assisted Intervention (AAI) Program.

Introduction: Previous studies have shown that apparently healthy animals participating in Animal-Assisted Interventions (AAI) have the potential to asymptomatically carry and even transmit zoonotic pathogens to people, which is of particular concern for therapy animal teams visiting healthcare settings. This two-part study was designed to investigate the risk of zoonotic pathogen transmission within a university-based AAI program as a combination of the prevalence of these pathogens in the animal population as well as the handlers' understanding of the risks of zoonoses in AAI and their adherence to infection control practices.Methods: In part one of the study, AAI program records were retrospectively reviewed and infectious disease screening test results were compiled from 22 dogs and 2 cats. Screening tests for dogs and cats included a zinc sulfate fecal float, fecal culture, and nasal and perianal skin swabs for methicillin-resistant Staphylococcus aureus (MRSA) and methicillin-resistant Staphylococcus pseudointermedius (MRSP). Additional tests for cats were blood cultures for Bartonella henselae and Toxoplasmosis IgG and IgM antibody titers. In part two, a survey was conducted of 40 registered therapy animal handlers to assess knowledge, attitudes, and perceptions regarding risk of infectious disease transmission in AAI settings, including risk to the animal, the handler, and those being visited.Results: In part one, there were 17 total positive results of the 118 infectious disease screenings performed, 14 of which were potentially zoonotic organisms. In part two of the study, a majority (70%) of respondents expressed they had no concerns regarding infectious disease transmission in AAI settings. Despite handler education and guidelines, adherence to infection control practices was lacking.Discussion: The results of this study support prior findings that animals participating in AAI can be asymptomatic carriers of zoonotic organisms. Compliance with infection control practices and hand hygiene are paramount to mitigate risk of zoonotic disease transmission, but was inconsistent among this group of handlers. Given the popularity of AAI programs in the U.S., similar studies should be performed on a larger scale to determine the level of adherence to currently recommended practices and potential need for improvement in infectious disease control education and/or policies.

Animal Husbandry Practices and Perceptions of Zoonotic Infectious Disease Risks Among Livestock Keepers in a Rural Parish of Quito, Ecuador.

Small-scale livestock production plays an essential role as a source of income and nutrition for households in low- and middle-income countries, yet these practices can also increase risk of zoonotic infectious diseases, especially among young children. To mitigate this risk, there is a need to better understand how livestock producers perceive and manage risks of disease transmission. Twenty semistructured, in-depth interviews were conducted with small-scale livestock producers in a semirural parish of Quito, Ecuador. Interviews explored livestock-raising practices, including animal health-care practices and use of antimicrobials, family members' interactions with livestock and other animals, and perceptions of health risk associated with these practices and activities. Interviews were analyzed for common themes. Awareness of zoonotic disease transmission was widespread, yet few study participants considered raising livestock a significant health risk for themselves or their families. Several study households reported handling and consuming meat or poultry from sick or dead animals and using animal waste as a fertilizer on their crops. Households typically diagnosed and treated their sick animals, occasionally seeking treatment advice from employees of local animal feed stores where medications, including antimicrobials, are available over the counter. Despite a basic understanding of zoonotic disease risk, this study identified several factors, such as the handling and consumption of sick and dead animals and purchasing medications for sick animals over the counter, that potentially increase the risk of zoonotic disease transmission as well as the development and spread of antimicrobial resistance.

Presence of Cryptosporidium parvum and Giardia lamblia in water samples from Southeast Asia: towards an integrated water detection system.

BackgroundAccess to clean and safe drinking water that is free from pathogenic protozoan parasites, especially Cryptosporidium parvum and Giardia lamblia that cause gastrointestinal illness in humans, is still an issue in Southeast Asia (SEA). This study is the first attempt to detect the aforementioned protozoan parasites in water samples from countries in SEA, using real-time polymerase chain reaction (qPCR) assays.MethodsA total of 221 water samples of 10 l each were collected between April and October 2013 from Malaysia (53), Thailand (120), the Philippines (33), and Vietnam (15). A physicochemical analysis was conducted. The water samples were processed in accordance with the US Environmental Protection Agency’s methods 1622/1623.1, microscopically observed and subsequently screened using qPCR assays.ResultsCryptosporidium oocysts were detected in treated water samples from the Philippines (1/10), with a concentration of 0.06 ± 0.19 oocyst/L, and untreated water samples from Thailand (25/93), Malaysia (17/44), and the Philippines (11/23), with concentrations ranging from 0.13 ± 0.18 to 0.57 ± 1.41 oocyst/L. Giardia cysts were found in treated water samples from the Philippines (1/10), with a concentration of 0.02 ± 0.06 cyst/L, and in untreated water samples from Thailand (20/93), Vietnam (5/10), Malaysia (22/44), and the Philippines (16/23), with concentrations ranging from 0.12 ± 0.3 to 8.90 ± 19.65 cyst/L. The pathogens C. parvum and G. lamblia were detected using using qPCR assays by targeting the 138-bp fragment and the small subunit gene, respectively. C. parvum was detected in untreated water samples from the Philippines (1/23) and Malaysia (2/44), whilst, G. lamblia detected was detected in treated water samples from the Philippines (1/10) and in untreated water samples from Thailand (21/93), Malaysia (12/44), and the Philippines (17/23). Nitrate concentration was found to have a high positive correlation with (oo)cyst (0.993).ConclusionThe presence of (oo)cysts in the water samples means that there is potential risk for zoonotic disease transmission in the studied countries. Detection using qPCR is feasible for quantifying both pathogenic C. parvum and G. lamblia in large water samples.

Orange County Vector Control and the County’s Feral Cat TNR Program: Ne’er the Twain Shall Meet?

In 2006, flea-borne rickettsiosis (flea-borne typhus), a zoonotic disease caused by either Rickettsia typhi or R. felis and transmitted primarily by two flea species, the Oriental rat flea and the cat flea, re-emerged as an important vector-borne disease in Orange County, California. The Orange County Mosquito and Vector Control District (OC Vector Control) has investigated 142 human cases of flea-borne rickettsiosis. Results of these investigations have established a link with Rickettsia-infected cat fleas, opossums, feral cats, and disease transmission to humans; no cases have been associated with rats and their fleas. Since initiation of a Trap-Neuter-Return (TNR) Program by Orange County (OC) Animal Care in 2009, OC Vector Control has been working with OC Animal Care to minimize the potential public health risks associated with the TNR Program. Interagency discussions have led OC Animal Care to prohibit the release of TNR cats at locations with a high risk for zoonotic disease transmission to humans, such as schools, parks, and health care facilities, and also to disclose the release sites to OC Vector Control. OC Animal Care has not agreed to OC Vector Control’s request for a zoonotic disease review of its TNR Program, nor has it provided a procedural manual to verify the verbal agreements reached by the two agencies. In agreement with OC Vector Control’s concerns, an investigation in 2015 by the Orange County Grand Jury of OC Animal Care’s TNR Program recognized the Program’s potential to increase zoonotic disease transmission to the public and other wildlife. We discuss the conflicting views arising from two governmental agencies, which perceive the zoonotic diseases risk associated with a TNR program at significantly different thresholds of concern.

Perceptions of zoonotic and animal diseases in the Van Gujjar community of North India

Humans living in and around forest areas are at increased risk of zoonotic disease transmission. The transhumant Van Gujjars of North India are one such population, but there is an absence of health data, including evidence of zoonotic diseases, in this community. Pastoral communities can have a wide breadth of knowledge of livestock diseases, but not necessarily of human diseases. This study investigated the perceptions that the Van Gujjars have specifically of zoonotic diseases, using participatory epidemiological methods, including semi-structured interviews, ranking, proportional piling, transect walks and direct observation, triangulated by informal interviews with local veterinarians. The community did not have a wide appreciation of zoonotic diseases, apart from rabies and potentially zoonotic skin diseases. In contrast, animal diseases were of much greater concern to the community; the locally-named surra (trypanosomiasis), ajar, khuriya (foot-and-mouth disease), dakhutra, gheru, taku, and ‘blood in urine’ (possibly babesiosis), being of most concern. A participatory epidemiological approach was found to be an effective method of data collection and analysis; and the findings suggest that access to health services, particularly veterinary health services, should be improved for Van Gujjars.

Cultural and Economic Motivation of Pig Raising Practices in Bangladesh.

The interactions that pig raisers in Bangladesh have with their pigs could increase the risk of zoonotic disease transmission. Since raising pigs is a cultural taboo to Muslims, we aimed at understanding the motivation for raising pigs and resulting practices that could pose the risk of transmitting disease from pigs to humans in Bangladesh, a predominantly Muslim country. These understandings could help identify acceptable strategies to reduce the risk of disease transmission from pigs to people. To achieve this objective, we conducted 34 in-depth interviews among pig herders and backyard pig raisers in eight districts of Bangladesh. Informants explained that pig raising is an old tradition, embedded in cultural and religious beliefs and practices, the primary livelihood of pig herders, and a supplemental income of backyard pig raisers. To secure additional income, pig raisers sell feces, liver, bile, and other pig parts often used as traditional medicine. Pig raisers have limited economic ability to change the current practices that may put them at risk of exposure to diseases from their pigs. An intervention that improves their financial situation and reduces the risk of zoonotic disease may be of interest to pig raisers.

Detection of Hepatitis E Virus Antibodies in Dogs in the United Kingdom.

Hepatitis E virus (HEV) genotypes 3 and 4 are zoonotic pathogens, with pigs predominantly implicated in disease transmission. The rapid rise in human cases in developed countries over the past decade indicates a change in epidemiology of HEV, and it has been suggested that additional animal species may be involved in transmission of infection. Multiple studies have identified contact with dogs as a risk factor for HEV infection in industrialised nations, and a low seroprevalence to HEV has previously been reported in dogs in low-income countries. In this study we aimed to evaluate the possibility that dogs are susceptible to HEV, and determine the frequency with which this occurs. Serum samples from UK dogs with and without hepatitis were screened for HEV-specific antibodies, and canine liver and stool samples were analysed by qPCR for the presence of HEV RNA. We describe evidence to show HEV infection occurs at low levels in dogs in the UK, but the strain of origin is undetermined. The low seroprevalence level of HEV in dogs implies the risk of zoonotic disease transmission is likely to be limited, but further investigations will be required to determine if HEV-infected dogs can transmit HEV to man.

Best practices for planning events encouraging human-animal interactions.

Educational events encouraging human-animal interaction include the risk of zoonotic disease transmission. It is estimated that 14% of all disease in the USA caused by Campylobacter spp., Cryptosporidium spp., Shiga toxin-producing Escherichia coli (STEC) O157, non-O157 STECs, Listeria monocytogenes, non-typhoidal Salmonella enterica and Yersinia enterocolitica were attributable to animal contact. This article reviews best practices for organizing events where human-animal interactions are encouraged, with the objective of lowering the risk of zoonotic disease transmission.

Roosting behaviour and habitat selection of Pteropus giganteus reveals potential links to Nipah virus epidemiology.

1. Flying foxes Pteropus spp. play a key role in forest regeneration as seed dispersers and are also the reservoir of many viruses, including Nipah virus in Bangladesh. Little is known about their habitat requirements, particularly in South Asia. Identifying Pteropus habitat preferences could assist in understanding the risk of zoonotic disease transmission broadly, and in Bangladesh, could help explain the spatial distribution of human Nipah virus cases. 2. We analysed characteristics of Pteropus giganteus roosts and constructed an ecological niche model to identify suitable habitat in Bangladesh. We also assessed the distribution of suitable habitat in relation to the location of human Nipah virus cases. 3. Compared to non-roost trees, P. giganteus roost trees are taller with larger diameters, and are more frequently canopy trees. Colony size was larger in densely forested regions and smaller in flood-affected areas. Roosts were located in areas with lower annual precipitation and higher human population density than non-roost sites. 4. We predicted that 2-17% of Bangladesh's land area is suitable roosting habitat. Nipah virus outbreak villages were 2.6 times more likely to be located in areas predicted as highly suitable habitat for P. giganteus compared to non-outbreak villages. 5. Synthesis and applications. Habitat suitability modelling may help identify previously undocumented Nipah outbreak locations and improve our understanding of Nipah virus ecology by highlighting regions where there is suitable bat habitat but no reported human Nipah virus. Conservation and public health education is a key component of P. giganteus management in Bangladesh due to the general misunderstanding and fear of bats that are a reservoir of Nipah virus. Affiliation between Old World fruit bats (Pteropodidae) and people is common throughout their range, and in order to conserve these keystone bat species and prevent emergence of zoonotic viruses, it is imperative that we continue to improve our understanding of Pteropus resource requirements and routes of virus transmission from bats to people. Results presented here can be utilized to develop land management strategies and conservation policies that simultaneously protect fruit bats and public health.

Dynamics of Rodent-Borne Zoonotic Diseases and Their Reservoir Hosts: Invasive Rattus in South Africa

Lack of adequate sanitation and pest control, and poor housing conditions that prevail in much of both rural and urban South Africa, cause rodent populations to thrive, promoting contact with humans, which results in increased risk of zoonotic disease transmission. This study focused on bacterial pathogens involved in potential zoonoses present in three commensal and invasive Rattus spp., namely Rattus norvegicus, R. rattus, and R. tanezumi, from rural and urban South Africa. Bacterial prevalence and diversity was determined through amplification and sequencing of the mitochondrial 16S gene region, using four primer sets: two that have a broad bacterial species recognition range, and two genus-specific sets that target the genera Streptococcus and Streptobacillus. An overall bacterial prevalence of 32% (n = 84) in kidney samples was obtained using the 16S universal primer sets. Subsequent sequence analyses found bacterial prevalence per host species to be 41% for R. norvegicus, 42% for R. rattus, and 8% for R. tanezumi, with representatives of diverse bacterial taxa such as Clostridium sordelli (toxic shock syndrome), Bacillus cereus (diarrhoeal disease), and Enterococcus faecalis (nosocomial infections) being characterised. The primer set targeting Streptobacillus moniliformis was used to determine the prevalence of this zoonotically-important bacterial taxon, which is transmissible via a bite from Rattus to humans, whilst Streptococcus-specific primers were used to assess environmental shedding of this agent via the urinary route. The results highlight the public health implications especially for immune-compromised individuals, as these rodent-borne pathogens can cause opportunistic infections that in such individuals are not readily diagnosed or treated.

Overview of aging research using nonhuman primate models

Overview of aging research using nonhuman primate models

Hunting of flying foxes and perception of disease risk in Indonesian Borneo

Widespread hunting of flying foxes has generated concern regarding population declines and the spread of emerging infectious diseases. To investigate the potential impacts of this trade, we conducted questionnaires in 45 settlements across 12 population centres within Central Kalimantan, Indonesia, a region previously identified as a hunting hotspot. By combining results from 63 hunter and 88 vendor interviews, we highlight two population centres (Palangka Raya and Buntok/Tamiang Layang) with higher hunting rates than other areas, which act as flying fox trading hubs. Flying fox populations were perceived to be declining province-wide: declines in captures and sales were reported by 81% of hunters and 60% of market vendors, who also reported availability as the key factor underlying temporal variations in trade. There was substantial risk of zoonotic disease transmission between bats, hunters and traders: the vast majority of respondents were unaware that flying foxes carry potentially fatal viruses, and so few people protected themselves from physical contact. Moreover, both hunters and vendors were frequently bitten and the majority of bites drew blood. Most hunters (58%) also reported unintentional by-catches that included keystone bird species and slow lorises. The scale of hunting over Central Kalimantan represents a serious threat to the long-term viability of flying fox populations (and potentially those of other species), and could have serious public health implications. Reducing or eliminating hunting and trade would mitigate the risk of disease transmission, while maintaining the economic and ecosystem benefits that flying foxes provide, in terms of pollination and seed dispersal.

Investigating Vietnam’s Ornamental Bird Trade: Implications for Transmission of Zoonoses

Global wildlife trade is financially lucrative, frequently illegal and increases the risk for zoonotic disease transmission. This paper presents the first interdisciplinary study of Vietnam's illegal wild bird trade focussing on those aspects which may contribute to the transmission of diseases such as Highly Pathogenic Avian Influenza (HPAI) H5N1. Comparing January 2009 data with that of May 2007, we found a five-fold increase to 9,117 birds on sale in Hanoi. Ninety-five percent of Hanoian bird vendors appear unaware of trade regulations and across Vietnam vendors buy birds sourced outside of their province. Approximately 25% of the species common to Vietnam's bird trade are known to be HPAI H5N1 susceptible. The anthropogenic movement of birds within the trade chain and the range of HPAI-susceptible species, often traded alongside poultry, increase the risk Vietnam's bird trade presents for the transmission of pathogens such as HPAI H5N1. These results will assist in the control and monitoring of emerging zoonotic diseases and conservation of Southeast Asia's avifauna.

Human–Bird Interactions in the United States Upland Gamebird Industry and the Potential for Zoonotic Disease Transmission

Since 1997, highly pathogenic avian influenza subtype H5N1 has emerged to cause severe disease in humans in over 15 countries. Humans who have regular contact with poultry or wild birds may be at greater risk of infection with highly pathogenic avian influenza and other zoonotic avian diseases. To develop preventative measures for transmission of avian influenza to high-risk human populations in the United States, we examined human-bird interactions in the upland gamebird industry. Upland gamebird permit holders were surveyed for information on human-bird contact, biosecurity practices, facility management practices, flock/release environment, and bird health. Results suggest that some upland gamebird facilities provide an environment for extensive and intimate human-bird interaction such that humans associated with these facilities may be at greater risk for zoonotic disease transmission.