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In March 2014, avian influenza in poultry in Laos was caused by an emergent influenza A(H5N6) virus. Genetic analysis indicated that the virus had originated from reassortment of influenza A(H5N1) clade 2.3.2.1b, variant clade 2.3.4, and influenza A(H6N6) viruses that circulate broadly in duck populations in southern and eastern China.

Although the majority of emerging infectious diseases can be linked to wildlife sources, most pathogen spillover events to people could likely be avoided if transmission was better understood and practices adjusted to mitigate risk. Wildlife trade can facilitate zoonotic disease transmission and represents a threat to human health and economies in Asia, highlighted by the 2003 SARS coronavirus outbreak, where a Chinese wildlife market facilitated pathogen transmission. Additionally, wildlife trade poses a serious threat to biodiversity. Therefore, the combined impacts of Asian wildlife trade, sometimes termed bush meat trade, on public health and biodiversity need assessing. From 2010 to 2013, observational data were collected in Lao PDR from markets selling wildlife, including information on volume, form, species and price of wildlife; market biosafety and visitor origin. The potential for traded wildlife to host zoonotic diseases that pose a serious threat to human health was then evaluated at seven markets identified as having high volumes of trade. At the seven markets, during 21 observational surveys, 1,937 alive or fresh dead mammals (approximately 1,009 kg) were observed for sale, including mammals from 12 taxonomic families previously documented to be capable of hosting 36 zoonotic pathogens. In these seven markets, the combination of high wildlife volumes, high risk taxa for zoonoses and poor biosafety increases the potential for pathogen presence and transmission. To examine the potential conservation impact of trade in markets, we assessed the status of 33,752 animals observed during 375 visits to 93 markets, under the Lao PDR Wildlife and Aquatic Law. We observed 6,452 animals listed by Lao PDR as near extinct or threatened with extinction. The combined risks of wildlife trade in Lao PDR to human health and biodiversity highlight the need for a multi-sector approach to effectively protect public health, economic interests and biodiversity.

African swine fever virus (ASFV) causes a deadly disease of pigs which spread through southeast Asia in 2019. We investigated one of the first outbreaks of ASFV in Lao People's Democratic Republic amongst smallholder villages of Thapangtong District, Savannakhet Province. In this study, two ASFV affected villages were compared to two unaffected villages. Evidence of ASFV‐like clinical signs appeared in pig herds as early as May 2019, with median epidemic days on 1 and 18 June in the two villages, respectively. Using participatory epidemiology mapping techniques, we found statistically significant spatial clustering in both outbreaks (p < 0.001). Villagers reported known risk factors for ASFV transmission – such as free‐ranging management systems and wild boar access – in all four villages. The villagers reported increased pig trader activity from Vietnam before the outbreaks; however, the survey did not determine a single outbreak source. The outbreak caused substantial household financial losses with an average of nine pigs lost to the disease, and Monte Carlo analysis estimated this to be USD 215 per household. ASFV poses a significant threat to food and financial security in smallholder communities such as Thapangtong, where 40.6% of the district's population are affected by poverty. This study shows ASFV management in the region will require increased local government resources, knowledge of informal trader activity and wild boar monitoring alongside education and support to address intra‐village risk factors such as free‐ranging, incorrect waste disposal and swill feeding.

Editor: Damia BarceloTrade of bushmeat and other wildlife for human consumption presents a unique set of challenges to policymakers who are confronted with multiple trade-offs between conservation, food security, food safety, culture and tradition. In the face of these complex issues, risk assessments supported by quantitative information would facilitate evidence-based decision making. We propose a conceptual model for disease transmission risk analysis, inclusive of these multiple other facets. To quantify several processes included in this conceptual model we conducted questionnaire surveys with wildlife consumers and vendors in semi-urban centers in Lao People's Democratic Republic (Lao PDR, Laos) and direct observations of consumer behaviors. Direct observation of market stalls indicated an estimated average of 10 kg j o u r n a l h o m e p a g e : w w w . e l s e v i e r . c o m / l o c a t e / s c i t o t e n v bushmeat biomass per stall per hour. The socio-demographic data suggested that consumption of bushmeat in urban areas was not for subsistence but rather driven by dietary preference and tradition. Consumer behavioral observations indicated that each animal receives an average of 7 contacts per hour. We provide other key parameters to estimate the risk of disease transmission from bushmeat consumption and illustrate their use in assessing the total public health and socio-economic impact of bushmeat consumption. Pursuing integrative approaches to the study of bushmeat consumption is essential to develop effective and balanced policies that support conservation, public health, and rural development goals.

. We found no correlation between in vitro susceptibility and in vivo protection (Spearman rank correlation coefficient ‫؍‬ ؊0.1; P > 0.05). Therefore, the in vivo efficacy of oseltamivir against highly pathogenic H5N1 influenza viruses cannot be reliably predicted by susceptibility testing, and more prognostic ways to evaluate anti-influenza compounds must be developed. Multiple viral and host factors modulate the effectiveness of NA inhibitor regimens against such viruses and new, more consistently effective treatment options, including combination therapies, are needed.

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Highly pathogenic porcine reproductive and respiratory syndrome (HP-PRRS) characterized by high fever, high morbidity, and high mortality in pigs of all ages emerged in China in 2006 and spread rapidly throughout Southeast Asia. In July 2010, a highly contagious swine disease with clinical signs similar to those of HP-PRRS was observed in the Lao People’s Democratic Republic (Lao PDR). A field investigation covering 8 pig farms and 1 slaughterhouse in 7 different districts in the capital city of Vientiane was conducted to identify the disease. Total mortality rates ranged from 6.02% in boars to 91.28% in piglets (mean 54.15%) across the farms investigated. Emergence of the HP-PRRS virus (HP-PRRSV) in Lao PDR was confirmed using real-time reverse transcription polymerase chain reaction as well as virus isolation and identification. An animal inoculation study was performed to characterize the HP-PRRSV responsible for this outbreak. Isolate Laos 1.13 was inoculated into 70-day-old specific pathogen–free pigs to study pathogenicity. Clinical signs of high fever, rubefaction, respiratory distress, nervous symptoms, and diarrhea were observed in inoculated pigs, as well as pathological hemorrhagic lesions consolidated in the lungs. Morbidity and mortality were 100% and 60%, respectively, in inoculated pigs. HP-PRRSV was re-isolated from the inoculated pigs. Results suggested that the newly emerged HP-PRRSV was responsible for recent outbreaks of the swine disease in Lao PDR. The current report highlights the importance of continuous surveillance in neighboring countries to prevent introduction of PRRS to new regions.