Outcomes of a Short-Duration, Large-Scale Canine Rabies Vaccination Campaign in Central Cambodia.

BACKGROUND: WHO and WOAH advocate for annual high-coverage canine rabies vaccination campaigns as the most sustainable approach to eliminate the risk of dog rabies transmission to humans. It is estimated that Cambodia has one of the highest human rabies deaths per capita of any country (5.8 human deaths per 100,000 people), highlighting the urgent need to implement an effective canine rabies vaccination program. To this end, a coalition of government and non-government organizations conducted a pioneering short-duration dog rabies vaccination campaign over 10 days across Phnom Penh and Kandal Provinces in May 2023. METHODS: Over 10 working days, 120 vaccination teams, each consisting of two vaccinators and one tuk-tuk driver, traveled door-to-door to deliver parenteral rabies vaccines to all dogs that could be held by the teams or members of the community. Spatial team management and data collection were conducted through the WVS Data Collection Application. RESULTS: A total of 74,983 dogs were vaccinated, giving a mean vaccination rate of 62.5 dogs per team per day. An additional 2145 cats were vaccinated. Of all dogs encountered by the teams, 84.0% could be vaccinated, with 99.1% of those being identified as owned. Post-vaccination surveys of 4356 households estimated a mean vaccination coverage of 70.7% in owned dogs across the districts of Phnom Penh Province. CONCLUSION: Short-duration, large-scale canine rabies vaccination campaigns can achieve high vaccination coverage using a door-to-door approach in urban centers of Cambodia. Data gathered through the campaign yielded insights to support the refinement and planning of a wider rabies control strategy and is anticipated to drive further support for subsequent campaigns in Cambodia.

Field and laboratory investigation of highly pathogenic avian influenza H5N6 and H5N8 in Quang Ninh province, Vietnam, 2020 to 2021.

BACKGROUND: Avian influenza (AI) is a contagious disease that causes illness and death in poultry and humans. High pathogenicity AI (HPAI) H5N6 outbreaks commonly occur in Quang Ninh province bordering China. In June 2021, the first HPAI H5N8 outbreak occurred at a Quang Ninh chicken farm. OBJECTIVES: This study examined the risk factors associated with HPAI H5N6 and H5N8 outbreaks in Quang Ninh. METHODS: A retrospective case-control study was conducted in Quang Ninh from Nov 2021 to Jan 2022. The cases were households with susceptible poultry with two or more clinical signs and tested positive by real-time reverse transcription polymerase chain reaction. The controls were households in the same village as the cases but did not show clinical symptoms of the disease. Logistic regression models were constructed to assess the risk factors associated with HPAI outbreaks at the household level. RESULTS: There were 38 cases with H5N6 clade 2.3.4.4h viruses (n = 35) and H5N8 clade 2.3.4.4b viruses (n = 3). Compared to the 112 controls, raising poultry in uncovered or partially covered ponds (odds ratio [OR], 7.52; 95% confidence interval [CI], 1.44-39.27), poultry traders visiting the farm (OR, 8.66; 95% CI, 2.7-27.69), farms with 50-2,000 birds (OR, 3.00; 95% CI, 1.06-8-51), and farms with ≥ 2,000 birds (OR, 11.35; 95% CI, 3.07-41.94) were significantly associated with HPAI outbreaks. CONCLUSIONS: Combining biosecurity measures, such as restricting visitor entry and vaccination in farms with more than 50 birds, can enhance the control and prevention of HPAI in Quang Ninh and its spread across borders.

A protocol and a data-based prediction to investigate virus spillover at the wildlife interface in human-dominated and protected habitats in Thailand: The Spillover Interface project.

The Spillover Interface Project aims at assessing the encounter of wildlife, domestic animals, and humans along a landscape gradient from a protected area to a residential community, through areas of reforestation and agricultural land. Here, we present the protocols of the project that combine virus screening in humans, bats, rodents and dogs with camera trapping, land-use characterization, and network analyses. The project is taking place in the sub-district of Saen Thong (Nan Province, Thailand) in collaboration with local communities, the District Public Health Office, and Nanthaburi National Park. To formulate a predictive hypothesis for the Spillover Interface Project, we assess the wildlife diversity and their viral diversity that could be observed in Saen Thong through a data science analysis approach. Potential mammalian species are estimated using data from the International Union for Conservation of Nature (IUCN) and their associated viral diversity from a published open database. A network analysis approach is used to represent and quantify the transmission of the potential viruses hosted by the mammals present in Saen Thong, according to the IUCN. A total of 57 viruses are expected to be found and shared between 43 host species, including the domestic dog and the human species. By following the protocols presented here, the Spillover Interface Project will collect the data and samples needed to test this data-driven prediction.

Economic and value chain analysis to support an investigation and risk mitigation efforts on Marek's disease in layers in the southern part of Thailand.

Background and Aim: Marek's disease (MD) is a common lymphoproliferative disease affecting chickens and causing economic losses in commercial poultry. The MD outbreak was noticed in the southern part of Thailand in 2019. The suspected cases were found with an abnormal number of cases of layers dying with clinical signs, for example, weakness and emaciation, with evidence of MD gross lesions. This study aimed to raise awareness of the MD outbreak through value chain analysis (VCA), identifying associated possible risk factors, and estimating the associated economic impact. Materials and Methods: Value chain analysis, including seasonal calendar, value chain diagram, and layer movement mapping of the layer industry, was conducted. High-risk stakeholders were identified on the basis of risk practices and interactions between stakeholders. A case-control study was conducted to determine risk factors associated with the MD outbreak on layer farms, and partial budget analysis was used to estimate economic losses associated with MD. Results: The value chain diagram showed the linkages between stakeholders, including estimation of the percentage of products moved from one stakeholder group to another and the negotiated price. Fourteen out of 35 layer farms were case farms. Farm size and source of birds were significantly associated with the MD outbreak. The MD outbreak caused total economic losses of 295,823 USD. Farms that slaughtered infected birds with additional revenues incurred losses of 140,930 USD, whereas farms that culled infected birds without additional revenue returned incurred losses of 1995 USD. Conclusion: The VCA provided a better understanding of the layer and egg businesses in South Thailand and guided the development of questionnaires for outbreak investigation. The potential risk factor findings suggested the need for further exploration of the source of the MD outbreak.

An exploratory study on the perceptions of rabies and ill-health causations and health seeking behaviours of school children and local communities in southern Bhutan.

BACKGROUND: The perception of illness and health-seeking behaviours, including rabies differ from one culture to another. Depending on the cultural setting of the society in which people live, the definition of the causal factors of illness may range from natural biological causes to supernational causes which greatly influence subsequent health-seeking behaviour. To ensure best health practices and plan effective health interventions for the control of dog-mediated-human rabies, we explored how school children and adult communities perceive and respond to illnesses, including rabies in southern Bhutan. METHODS: We collected quantitative data related to the causes of illness and health-seeking practices of school children using a questionnaire survey (QS). Qualitative data were collected through focus group discussions (FGDs) and in-depth interviews (IDIs) with older members of communities (≥ 18 years) that work closely with school children. Descriptive analysis was performed for the quantitative data and thematic analysis was performed for the qualitative data. RESULTS: The participants during the FDGsand IDIshave linked the illnesses to past actions, spirits, energy channels, planetary movement, sorcery, black magic, food, physical or environmental factors, individual habits and social factors. The survey of the school children reported microorganisms (75%), past actions (16.8%), spirits (9.6%) and black magic (9.1%) as causal factors for illnesses. Health seeking behaviours reported by the participants included visiting hospitals, performing spiritual or religious rituals and local treatments. Similarly, school children also mentioned that illnesses can be treated by visiting hospitals (98%), performing rituals (59.1%), and seeking traditional treatments practices (18.8%). Both school children and adult members of the communities that we interviewed were well aware on the causes of rabies and need for allopathic treatments rather than seeking spiritual or local treatments. CONCLUSION: There is a need for the consideration of the socio-cultural context in the planning and implementation of health-related policies, including the rabies prevention programs in Bhutan, by involving traditional healers and religious entities with "One Health" public health sectors.

Serological Detection of Toxoplasma gondii among Free-Grazing Ducks from Central and Western Thailand-A One Health Perspective on Integrated Farming.

Toxoplasmosis is one of the most common zoonotic parasitic diseases infecting nearly all warm-blooded animals, including poultry (geese, turkeys, chickens, and ducks). It is caused by Toxoplasma gondii (T. gondii), which is an obligate intracellular protozoan belonging to the Apicomplexa group. In Thailand, duck meat production for domestic consumption and international trade is mainly bred and produced in the central and western parts of the country. Free-grazing ducks in integrated duck-rice production have significant benefits in rice cultivation, accounting for the popularity of this farming system in Thailand. However, ducks are considered particularly susceptible to consuming T. gondii oocysts from water contaminated with cat feces due to the fact of their feeding habits of free-grazing and dabbling. Hence, the prevalence of this zoonotic parasite in a large-scale integrated farming context is particularly challenging with respect to the contamination of the food chain of humans and farm animals. In the present study, we examined the overall prevalence of T. gondii infection in slaughtered free-grazing ducks originating from Central and Western Thailand, setting the stage for an in-depth One Health approach to assess and manage the risks of integrated farming practices. A representative sample size of 161 ducks was calculated using a two-stage sampling method. Specifically, serum samples were collected from 217 slaughtered free-grazing ducks originating in six provinces in Central and Western Thailand. Serum antibodies against T. gondii were detected using an indirect fluorescent antibody test (IFAT). The positive control serum samples were prepared from ducks experimentally immunized with T. gondii. Sixty-eight (31.3%) of the two hundred and seventeen ducks were seropositive with T. gondii. Two groups of fattening ducks and spent layers showed similar seropositivity rates at 29% and 32.3%, with the majority of positive samples being found in the low titer. In addition, a wide distribution of positive serum samples was observed in all six provinces in the present study. To the best of our knowledge, this is the first report on a serological prevalence snapshot in commercially produced duck populations that have high interaction with farmed environments in Thailand, revealing a high infection pressure in areas of integrated duck-rice farming. Importantly, contaminated duck meat for commercial use, as well as offal and carcasses from slaughterhouses, completes the transmission of T. gondii from the environment into the food chain of humans and domestic animals. Hence, from a One Health perspective, it is important to clarify whether this transmission chain extends further to the wild, i.e., predator-prey cycles that are independent of duck farming or are self-contained.

Assessment of the rabies education among middle secondary school students of southeastern Bhutan.

Rabies is one of the most important zoonotic diseases that mostly affect children. We conducted a rabies education among 129 secondary school children (intervention group = 94 students, control group = 35 students) in two schools in southeast Bhutan and evaluated the effectiveness of the lesson by comparing the knowledge, perception and safety behaviour score about rabies before and after education. We also assessed the knowledge retention capacity of the students at three months post intervention. Our findings indicated that short rabies lesson significantly (P<0.001) improved the mean knowledge score from 19.98(±2.72) to 26.96(±2.24) in the intervention group. Similarly, mean scores for perception and safety behaviour improved significantly (P<0.001) from 10.77 (±1.89) to 13.95 (±1.36) and 9.809 (±1.85) to 12.97 (±1.54), respectively. Although the scores have reduced significantly (P<0.001) at three months post intervention, most of the rabies information was largely retained by the students. In control group, significant increase in mean scores were also observed for perception from 10.17 (±2.38) to 11.2 (±2.44) and safety behaviour from 9.14(±1.44) to 10.74 (±1.95) after 3 months of education. The finding demonstrate that a short rabies lesson is effective in improving knowledge, perceptions and understanding of dog bites safety behaviour among the school children. However, there is a need for a frequent awareness program, at least quarterly or half yearly. Rabies education should focus on critical points such as dog bites being the main source of rabies and the importance washing a dog/animal bite wound with soap and water, and visiting the hospital for medical advice following animal bites.

An economic analysis of high milk somatic cell counts in dairy cattle in Chiang Mai, Thailand.

Mastitis in dairy cattle can lead to significant financial losses due to a reduction in milk yield, the withdrawal period after treatment when milk cannot be sold, and an increase in somatic cell count (SCC) which can reduce the milk's per liter commercial value. Dairy cooperatives point at high-SCC problems as an important factor leading to suboptimal levels of milk quantity and quality. This study aims at describing farm characteristics and milking practices associated with high SCC, identifying risk factors, and assessing the economic loss due to high SCC in three dairy cooperatives in Chiang Mai, Thailand. A cross-sectional study was conducted on 208 dairy cattle farms from July to September 2018. Structured interviews were conducted to collect the data. Univariate and multivariate analyses were performed to determine the degree of association between factors and high SCC. A retrospective cost assessment of high SCC was conducted to estimate the losses in affected farms, and two potential coping strategies were assessed: (1) culling and (2) treating the cow. More than 12% of farms had high SCC (SCC > 500,000 cells/ml). Inappropriate vacuum pressure and inappropriate pulsation rate of milking machines were identified as significant risk factors according to the multiple logistic regression (P < 0.01). Both factors can decrease the natural protection of teat tissue, increasing the likelihood of bacterial infection. The average economic loss of high SCC in affected farms was 557 USD for a three-month period. When comparing response strategies (i.e., treatment vs. culling), treating the affected cow was found to be more cost-effective. With a probability of successful treatment of 54%, treating an affected cow leads to 1,158.7 USD in gains over 3 years (vs. doing nothing). The results of this economic analysis can be used to advocate to cooperatives the value of veterinarians and for investigating and treating cases of mastitis.

Viability of Toxoplasma gondii tachyzoites in different conditions for parasite transportation.

Background and Aim: Toxoplasma gondii tachyzoite is the infective stage that causes acute infection, leading to severe toxoplasmosis. The tachyzoite stage has been extensively used for several inoculation purposes, including antigen production, immunological studies, nutrition mechanisms, and in vitro drug trials. The use of fresh tachyzoites is required for inoculation in either in vitro or in vivo studies. However, there is a lack of information on preserving live tachyzoites during transportation from laboratories to inoculation sites. Therefore, this study aimed to validate suitable preservative conditions for maintaining live parasites by determining the survival and viability of T. gondii tachyzoites on the basis of different media, temperatures, and incubation times. Materials and Methods: The free live T. gondii tachyzoites were evaluated on their viability when maintained in different media without 5% Carbon dioxide (CO2). The purified tachyzoites of the RH and PLK strains were individually suspended in normal saline (NS), phosphate-buffered saline (PBS), minimum essential medium (MEM), and MEM with 10% fetal bovine serum (MEM-FBS) and incubated for 6 h at ice-cold (IC; 3-9°C) and room temperature (RT; 25°C). Parasite survival was measured at the 0, 1st, 2nd, 3rd, 4th, 5th, and 6th h post-incubation using the trypan blue exclusion test. Results: The viability was in the range of 85.0%-91.0% for IC using NS and 81.0%-85.1% (IC) and 75.3%-77.5% (RT) using PBS. The viability was approximately 75.0%-83.0% (IC) and 70.0%-79.0% (RT) using MEM and MEM-FBS. There was a significant difference in the viability between the seven periods on the basis of one-way repeated Analysis of variance and Friedman analyses. Parasite survival slightly reduced (20.0%-30.0%) in NS and MEM-FBS at both temperatures during incubation. Notably, PBS could not support tachyzoite viability after 3 h post-incubation. Conclusion: NS was a suitable preservative for maintaining purified T. gondii tachyzoites during transportation at IC and RT without 5% CO2 supplementation. This could be a valuable medium for parasite transportation, especially when there is a large distance between the laboratory and inoculation site.

Analyses of Contact Networks of Community Dogs on a University Campus in Nakhon Pathom, Thailand.

Free-roaming dogs have been identified as an important reservoir of rabies in many countries including Thailand. There is a need for novel insights to improve current rabies control strategies in these countries. Network analysis is commonly used to study the interactions between individuals or organizations and has been applied in preventive veterinary medicine. However, contact networks of domestic free-roaming dogs are mostly unexplored. The objective of this study was to explore the contact network of free-roaming dogs residing on a university campus. Three one-mode networks were created using co-appearances of dogs as edges. A two-mode network was created by associating the dog with the pre-defined area it was seen in. The average number of contacts a dog had was 6.74. The normalized degree for the weekend network was significantly higher compared to the weekday network. All one-mode networks displayed small-world network characteristics. Most dogs were observed in only one area. The average number of dogs which shared an area was 8.67. In this study, we demonstrated the potential of observational methods to create networks of contacts. The network information acquired can be further used in network modeling and designing targeted disease control programs.

Knowledge, attitude, and practices associated with rabies in villages with different dog vaccination statuses in Cambodia.

BACKGROUND AND AIM: Rabies is a highly infectious but neglected zoonotic disease. Almost 99% of rabies-related human deaths are caused by dog-mediated rabies. Although canine rabies vaccination is highly effective and provides protection, nationwide rabies vaccination campaigns have been insufficient in Cambodia, resulting in a limited number of rabies vaccinated dogs. This study aimed to explore the rabies knowledge, attitude, and practices (KAP) among participants from both dog rabies vaccinated (DRV) and dog rabies unvaccinated (DRUV) villages located in the Kandal and Prey Veng Provinces, Cambodia. MATERIALS AND METHODS: A cross-sectional survey was conducted with dog owners in Kandal and Prey Veng Provinces, Cambodia, during August and September 2020. The structural questionnaire collected general sociodemographic information and the KAP associated with rabies transmission, clinical signs, management, and control. The data were then analyzed using Wilcoxon rank-sum test and Chi-square statistics. RESULTS: In total, 312 participants were interviewed: 137 participants from DRV villages and 175 from DRUV villages. Among them, 99.4% (310/312) had previously heard about rabies. Out of these 310, 93.5% (290/310) were aware that rabies is a fatal disease, while 96.5% (299/310) were willing to vaccinate their dog against rabies if the vaccination was provided for free. However, 32.9% (102/310) indicated that they would be willing to sell their own dog if it bit someone or showed aggression. More than one-third (115/310) of all the respondents had poor overall KAP regarding rabies. The respondents from DRV villages had significantly higher overall scores with regard to rabies KAP than those from DRUV villages (p<0.0001). According to the factors related to overall KAP, village type and education level were significantly associated with overall KAP of the respondents (p<0.0001). CONCLUSION: The rabies disease is recognized in Cambodia, and dog owners are willing to vaccinate their dogs if the vaccination is provided for free. The overall rabies-related KAP were poor among 30% of the respondents, and higher KAP scores were obtained for the DRV villages. The village type and education level were found to be associated with the different overall KAP of the participants.

Knowledge and Perception of Rabies among School Children in Rabies Endemic Areas of South Bhutan.

Rabies is endemic in southern Bhutan and children are the frequent victims of dog bites. We surveyed the knowledge, attitude, and practices on rabies among school children in three schools located in southern Bhutan. A total of 701 students (57.9% female, 42.1% male) with an age range of 12-21 years (mean: 15 years) participated in the survey, of which 98.2% had heard about rabies. Most of the students demonstrated a good level of knowledge (59.7%) and a favorable perception towards rabies (57.7%). Multivariable logistic analysis revealed the relation between knowledge and the awareness campaign (OR:1.5, 95% CI: 1.1-2.1). Similarly, higher grades of students (OR:1.9, 95%CI: 1.3-2.9) and employed mothers of the students (OR: 1.6, 95% CI: 1.0-2.7) were associated with more favorable perceptions. However, some knowledge gaps were identified in this study, such as students not being able to clearly mention the susceptible hosts of rabies, transmission routes, clinical signs, and prevention and control options. Therefore, regular awareness programs on rabies are necessary among school children in Bhutan.

Seroprevalence and risk factors of canine distemper virus in the pet and stray dogs in Haa, western Bhutan.

BACKGROUND: Canine Distemper Virus (CDV) is a highly contagious virus belonging to family Paramyxovirade, genus Morbillivirus and responsible for high morbidity and mortality in dogs worldwide. Infected domestic dogs can cause spillover infections to wild carnivores that are in contact. We conducted a seroprevalence survey of CDV in domestic dogs in two areas of western Bhutan (Haa district) located at the periphery of the Jigme Khesar Strict Nature Reserve, which is home to several endangered wildlife. A total of 238 serum samples, 119 each from the pet and stray dog, were collected during summer and winter seasons. Samples were tested for CDV antibodies using a sandwich enzyme-linked immune-sorbent assay (ELISA) test. RESULTS: The seroprevalence of CDV was found to be 11.3% (95% CI 6.7-14.2). Dogs sampled during winter were less likely to test seropositive against CDV antibodies than those sampled during summer (adjusted odds ratio: -2.6; 95% CI: - 1.2-6.1). Dogs in good body condition were found to be more likely to test seropositive against CDV than dogs in poor condition and obese dogs (adjusted odds ratio: 2.2; 95% CI: 0.1-5.9). There were no significant differences in the seroprevalence of CDV among different sexes, breeds and age classes, pet and stray dogs and between the two study sites. CONCLUSIONS: Our study indicates that CDV seroprevalence was equally distributed among pet and stray dogs. We suggest strengthening the management practices of dogs through responsible dog ownership, dog population management and waste management to minimize the transmission risk of infectious diseases to wildlife.

"Health in" and "Health of" Social-Ecological Systems: A Practical Framework for the Management of Healthy and Resilient Agricultural and Natural Ecosystems.

The past two decades have seen an accumulation of theoretical and empirical evidence for the interlinkages between human health and well-being, biodiversity and ecosystem services, and agriculture. The COVID-19 pandemic has highlighted the devastating impacts that an emerging pathogen, of animal origin, can have on human societies and economies. A number of scholars have called for the wider adoption of "One Health integrated approaches" to better prevent, and respond to, the threats of emerging zoonotic diseases. However, there are theoretical and practical challenges that have precluded the full development and practical implementation of this approach. Whilst integrated approaches to health are increasingly adopting a social-ecological system framework (SES), the lack of clarity in framing the key concept of resilience in health contexts remains a major barrier to its implementation by scientists and practitioners. We propose an operational framework, based on a transdisciplinary definition of Socio-Ecological System Health (SESH) that explicitly links health and ecosystem management with the resilience of SES, and the adaptive capacity of the actors and agents within SES, to prevent and cope with emerging health and environmental risks. We focus on agricultural transitions that play a critical role in disease emergence and biodiversity conservation, to illustrate the proposed participatory framework to frame and co-design SESH interventions. Finally, we highlight critical changes that are needed from researchers, policy makers and donors, in order to engage communities and other stakeholders involved in the management of their own health and that of the underpinning ecosystems.

Antimicrobial Resistance of Salmonella spp. Isolates and Heavy Metal Traces from Rodent Meat Purchased from Roadside Markets, Central Thailand.

Although game meat consumption is widespread across the globe, involving a great diversity of species in very different ecological and sociocultural environments, the safety of wild meat products is rarely assessed routinely. We conducted a survey to evaluate the safety of two rodents products (Rattus tanezumi and Bandicota indica) purchased from roadside markets in central Thailand. Total aerobic bacteria and Escherichia coli counts measured were above Thai poultry product standards for 83.3% and 100% of the samples, respectively (n = 108), although there was no difference between rat species (analysis of variance [ANOVA], p > 0.05). Salmonella spp. were isolated from 32% of the swabs collected (67/208), including 19 different serovars. All strains were resistant or partially resistant to at least 2 of the 16 antibiotics tested, with levels of resistance varying greatly among antibiotics (e.g., 97% of strains sensitive to ciprofloxacin and 98.5% of strains resistant to cloxacillin). Detectable traces of Cd and Pb were found in 98% and 46% of the samples analyzed, respectively (n = 61). Pb and Cd concentrations measured in the kidneys of R. tanezumi were significantly higher than in the liver and muscles and significantly higher than B. indica muscles and kidneys but not liver (ANOVA, p < 0.05). These results highlight potential health hazards that may be associated with rodent-meat consumption, including contamination by coliform bacteria, multiresistant Salmonella spp. strains, and heavy metals. The significance of these results for public health cannot be determined precisely in the absence of appropriate standards, and information gaps remain regarding the frequency of rodent-meat consumption and the origin of bacterial and heavy metal contaminations (i.e., capture environment or during carcass handling and processing). We suggest that appropriate information and training on best hygienic practices for preparing, cooking, and preserving rodent meat should be provided to the producers and to the consumers.

Social Influence in Liver Fluke Transmission: Application of Social Network Analysis of Food Sharing in Thai Isaan Culture.

In northeastern Thai (Isaan) culture traditional raw fish dishes and raw fish-eating habits are common. Eating and sharing meals together among the community's members, especially relatives and neighbours, are a common practice in both daily life and social gathering events. Fish are a significant protein source and are associated with variety of traditional recipes. Cyprinid fish are one of the most preferred fish by Isaan villagers for daily consumption because they are accessible and affordable. Consumption of these fish probably causes the persistence of high endemicity of human liver fluke infection, particularly with Opisthorchis viverrini, in northeast Thailand. Because the consumption of raw cyprinid fish is a well-documented risk factor for liver fluke infection, sharing of risky raw fish dishes may influence disease transmission through a community. Social network analysis was used to investigate fish and fish-based meal sharing among household members in Isaan villages in liver fluke endemic areas. The findings from three studies confirmed the persistence of traditional Isaan raw fish consumption and food-sharing practice. Social connections via food sharing among villagers played an important role in liver fluke infection and transmission dynamics as a risk factor. Thus these sociocultural factors should be taken into account in designing strategies for control of opisthorchiasis and other food-borne illnesses at the community level.

Potentially hazardous Streptococcus suis strains latent in asymptomatic pigs in a major swine production area of Thailand.

PURPOSE: Carrier pigs have been considered as the major reservoir of Streptococcus suis and couldbe a significant source of human infection. Therefore, we investigated the prevalence and characteristics of latent S. suis in asymptomatic pigs in the pig-farming area of central Thailand, and compared the data to those previously reported in other regions. METHODOLOGY: We collected samples from 340 asymptomatic pigs. S. suis isolates from the samples were confirmed by species-specific PCR (recN PCR). The capsular polysaccharide synthesis gene (cps) types, virulence-associated gene profiles and sequence types (STs) of the isolates were investigated.Results/Key findings. The prevalence of S. suis found in this study was 37 % (125/340 pigs). The most prevalent genotype was mrp-/epf-/sly-. Among the 16 cps-types identified in 135 isolates, cps-type 16 was the most frequent (11 %), whereas 44 % of the isolates were non-typable. In common with the strains causing human sepsis in Thailand, two cps-type 9 isolates and a cps-type 24 isolate from slaughtered pigs belonged to ST16 and ST221, respectively. All the isolated cps-type 2 strains were confirmed as serotype 2 by co-agglutination tests, and these belonged to ST104, the unique ST commonly found in Thai patients; however, in contrast to the endemic areas, the prevalence of serotype 2 strains was relatively low (2 %) and no ST1 isolate was found. CONCLUSION: Our results showed the population structure differences between S. suis in central Thailand and other regions; however, zoonotic S. suis is certainly latent in asymptomatic pigs in this intensive swine production area.

Social network analysis of food sharing among households in opisthorchiasis endemic villages of Lawa Lake, Thailand.

Consumption of raw fish is a well-documented risk factor for Opisthorchis viverrini infection. Sharing of food, especially raw fish recipes may influence the spread of disease through a community. Using social network analysis of an ego network, we investigated food sharing among households in an Opisthorchis-endemic area. Network centrality properties were used to explain the differences in O. viverrini transmission and control between villages with a low and high prevalence of infection. Information on demography and O. viverrini infection in 2008 from villagers in the Lawa Lake area was extracted from the Tropical Disease Research Center database. The two villages that had the lowest and the highest O. viverrini infection at the household level were recruited. Ten percent of households of each village were randomly sampled. Participatory epidemiology and face-to-face structured interviews guided by a social network questionnaire were used to collect data on livelihood, agricultural patterns, food sources, raw fish eating habits, and other food sharing during daily life and social gatherings. The number of contacts including in-degree and out-degree varied from 0 to 7 in the low-infection village and 0 to 4 in the high-infection village. The mean number of contacts for the food-sharing network among the low- and high-infection villages was 1.64 and 0.73 contacts per household, respectively. Between these villages, the mean number of out-degree (p=0.0125), but not in-degree (p=0.065), was significantly different. Food-sharing differed in numbers of sharing-in and sharing-out between the two villages. Network analysis of food sharing may be of value in designing strategies for opisthorchiasis control at the community level.

Risk factors for Clonorchis sinensis infection transmission in humans in northern Vietnam: A descriptive and social network analysis study.

Clonorchis sinensis is major fish-borne trematode, endemic in North Vietnam. Risk factors described so far include individual eating behaviors and environmental factors. Here, additional to conventional risk factors, we report on socially influenced liver fluke transmission in endemic communities. A cross-sectional study on risk factors and fish sharing networks was conducted in 4 villages of Gia Thinh Commune, Ninh Binh Province. A total of 510 residents in 272 households were recruited for risk factor analysis while 220 households, 28 fishermen and 10 fish-sellers were enrolled for social network study. Fecal examination for C. sinensis eggs was performed. Average C. sinensis infection rate at Gia Thinh commune was 16.5% (range 2% to 34.4%). Higher infection rates were significantly associated with males, lower educational levels, eating raw fish, and location of the villages. Social network analysis (SNA) showed a strong positive correlation between ego network size (number of households in fish sharing network) and quantity of raw fish consumed (r=0.603, P<0.05). The infection rate in people who ate raw-fish caught from a nearby river was significantly higher than those who consumed fish taken from farmed ponds (P<0.05). The amount of raw-fish meal consumed per resident/year was significantly higher in villages that had a strong network of sharing raw-fish food (P<0.001). This study reports for the first time on fish-food sharing among neighbors, proximity to water bodies, frequency of eating raw fish from natural water bodies and low education were key risk factors in C. sinensis infection transmission in northern Vietnam.

A framework to promote collective action within the One Health community of practice: Using participatory modelling to enable interdisciplinary, cross-sectoral and multi-level integration.

As Southeast Asia (SEA) is characterized by high human and domestic animal densities, growing intensification of trade, drastic land use changes and biodiversity erosion, this region appears to be a hotspot to study complex dynamics of zoonoses emergence and health issues at the Animal-Human-Environment interface. Zoonotic diseases and environmental health issues can have devastating socioeconomic and wellbeing impacts. Assessing and managing the related risks implies to take into account ecological and social dynamics at play, in link with epidemiological patterns. The implementation of a One Health (OH) approach in this context calls for improved integration among disciplines and improved cross-sectoral collaboration, involving stakeholders at different levels. For sure, such integration is not achieved spontaneously, implies methodological guidelines and has transaction costs. We explore pathways for implementing such collaboration in SEA context, highlighting the main challenges to be faced by researchers and other target groups involved in OH actions. On this basis, we propose a conceptual framework of OH integration. Throughout 3 components (field-based data management, professional training workshops and higher education), we suggest to develop a new culture of networking involving actors from various disciplines, sectors and levels (from the municipality to the Ministries) through a participatory modelling process, fostering synergies and cooperation. This framework could stimulate long-term dialogue process, based on the combination of case studies implementation and capacity building. It aims for implementing both institutional OH dynamics (multi-stakeholders and cross-sectoral) and research approaches promoting systems thinking and involving social sciences to follow-up and strengthen collective action.