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The duration of humoral and cellular immune memory following SARS-CoV-2 infection in populations in least developed countries remains understudied but is key to overcome the current SARS-CoV-2 pandemic. Sixty-four Cambodian individuals with laboratory-confirmed infection with asymptomatic or mild/moderate clinical presentation were evaluated for Spike (S)-binding and neutralizing antibodies and antibody effector functions during acute phase of infection and at 6-9 months follow-up. Antigen-specific B cells, CD4+ and CD8+ T cells were characterized, and T cells were interrogated for functionality at late convalescence. Anti-S antibody titers decreased over time, but effector functions mediated by S-specific antibodies remained stable. S- and nucleocapsid (N)-specific B cells could be detected in late convalescence in the activated memory B cell compartment and are mostly IgG+. CD4+ and CD8+ T cell immune memory was maintained to S and membrane (M) protein. Asymptomatic infection resulted in decreased antibody-dependent cellular cytotoxicity (ADCC) and frequency of SARS-CoV-2-specific CD4+ T cells at late convalescence. Whereas anti-S antibodies correlated with S-specific B cells, there was no correlation between T cell response and humoral immune memory. Hence, all aspects of a protective immune response are maintained up to nine months after SARS-CoV-2 infection and in the absence of re-infection.

To better understand the potential risks of Nipah virus emergence in Cambodia by studying different components of the interface between humans and bats.From 2012 to 2016, we conducted a study at two sites in Kandal and Battambang provinces where fruit bats (Our results confirmed circulation of Nipah virus in fruit bats (28 of 3930 urine samples positive by polymerase chain reaction testing). We identified clear potential routes for virus transmission to humans through local practices, including fruit consumed by bats and harvested by humans when Nipah virus is circulating, and palm juice production. Nevertheless, in the serological survey of 418 potentially exposed people, none of them were seropositive to Nipah virus. Differences in agricultural practices among the regions where Nipah virus has emerged may explain the situation in Cambodia and point to actions to limit the risks of virus transmission to humans.Human practices are key to understanding transmission risks associated with emerging infectious diseases. Social science disciplines such as anthropology need to be integrated in health programmes targeting emerging infectious diseases. As bats are hosts of major zoonotic pathogens, such integrated studies would likely also help to reduce the risk of emergence of other bat-borne diseases.Mieux comprendre les risques potentiels d'émergence du virus Nipah au Cambodge en étudiant différents composants de l'interface entre humains et chauves-souris.De 2012 à 2016, nous avons réalisé une étude à deux endroits dans les provinces de Kandal et Battambang, où nichent les chauves-souris frugivores (Nos résultats ont confirmé la circulation du virus Nipah chez les chauves-souris frugivores (28 échantillons d'urine sur 3930 se sont révélés positifs lors des tests de réaction en chaîne par polymérase). Nous avons clairement identifié plusieurs vecteurs de transmission potentiels aux humains liés aux pratiques locales, dont les fruits consommés par les chauves-souris et récoltés par les humains lorsque le virus Nipah circule, ainsi que la production de jus de palme. Néanmoins, une enquête sérologique menée auprès de 418 personnes potentiellement exposées a montré qu'aucune d'entre elles n'était séropositive au virus Nipah. Les différences au niveau des pratiques agricoles dans les régions où le virus Nipah est apparu pourrait expliquer la situation au Cambodge, et conduire à des actions qui permettront de limiter les risques de transmission du virus aux humains.Les pratiques humaines sont la clé d'une meilleure compréhension des risques de transmission associés aux maladies infectieuses émergentes. Certaines disciplines de sciences sociales telles que l'anthropologie doivent être intégrées dans les programmes de santé qui ciblent les maladies infectieuses émergentes. Étant donné que les chauves-souris sont porteuses d'agents pathogènes zoonotiques majeurs, des études intégrées de ce type pourraient contribuer à réduire le risque d'émergence d'autres maladies propagées par les chauves-souris.Entender mejor los riesgos potenciales de la aparición del virus Nipah en Camboya mediante el estudio de los diversos componentes de la interfaz entre los seres humanos y los murciélagos.De 2012 a 2016, se realizó un estudio en dos lugares de las provincias de Kandal y Battambang en donde habitan los murciélagos fruteros (Los resultados confirmaron la circulación del virus Nipah en murciélagos fruteros (28 de 3930 muestras de orina positivas en la prueba de reacción en cadena de la polimerasa). Se identificaron las rutas claras de transmisión del virus a los seres humanos a través de las prácticas locales, incluidas las frutas que consumen los murciélagos y que los seres humanos recolectan cuando el virus Nipah está en circulación, y la producción de zumo de palma. Sin embargo, según el estudio serológico de 418 personas potencialmente expuestas, ninguna de ellas fue seropositiva al virus Nipah. Es posible que las diferencias en las prácticas agrícolas entre las regiones en donde el virus Nipah se ha presentado expliquen la situación en Camboya y señalen las medidas para limitar los riesgos de transmisión del virus a los seres humanos.Las prácticas de los seres humanos son esenciales para entender los riesgos de transmisión asociados a las enfermedades infecciosas emergentes. Las disciplinas de las ciencias sociales, como la antropología, se deben integrar en los programas de salud que se ocupan de esas enfermedades. Teniendo en cuenta que los murciélagos son huéspedes de los principales patógenos zoonóticos, es probable que esos estudios integrados también ayuden a reducir el riesgo de aparición de otras enfermedades que se transmiten por los murciélagos.الغرض تحقيق فهم أفضل للمخاطر المحتملة لظهور فيروس نيباه في كمبوديا عن طريق دراسة المكونات المختلفة للتفاعل بين البشر والخفافيش. الطريقة من عام 2012 حتى عام 2016، قمنا بإجراء دراسة في موقعين في مقاطعتي كاندال وباتامبانج حيث تستوطن خفافيش الفاكهة (旨在通过研究人与蝙蝠之间相互接触的不同部分，更好地了解柬埔寨境内的尼帕病毒潜在风险。.从 2012 年至 2016 年，我们在坎达尔和马德望省的两个地点进行了研究，这些地方都栖息着果蝠（我们的结果证实了尼帕病毒在果蝠中的传播（通过聚合酶链反应测试发现 3930 个尿液样本中有 28 个呈阳性）。我们通过当地实践确定了将病毒传播给人类的明确潜在途径，包括传播尼帕病毒时蝙蝠食用的和人类收获的果实，以及棕榈汁的生产。尽管如此，在对 418 名潜在接触者进行的血清学调查中，没有人对尼帕病毒呈血清反应阳性。已经出现尼帕病毒的地区中在农业实践方面的差异可能说明了柬埔寨的情况以及限制病毒传播给人类的风险的行动指向。.人类实践是了解与新发传染病相关的传播风险的关键。需要将人类学等社会科学学科纳入针对新发传染病的卫生方案。由于蝙蝠是主要的人畜共患病病原体的宿主，因此此类综合研究还可能有助于降低其他蝙蝠传播疾病出现的风险。.Добиться лучшего понимания потенциальных рисков появления вируса Нипах в Камбодже за счет изучения разного рода компонентов взаимодействия людей и летучих мышей.В период с 2012 по 2016 год авторы провели исследование в двух районах провинций Кандаль и Баттамбанг со значительными колониями крыланов (Было подтверждено, что в организмах крыланов циркулирует вирус Нипах (28 из 3930 образцов мочи были положительными по результатам тестирования методом полимеразной цепной реакции). Авторы выявили четкие потенциальные пути передачи вируса людям через принятые в этих местностях практикуемые виды деятельности, включая сбор людьми фруктов, которыми питаются крыланы, во время циркуляции вируса Нипах и добычу пальмового сока. Тем не менее в серологическом исследовании 418 потенциально зараженных людей ни один человек не продемонстрировал положительного результата при серологической диагностике вируса Нипах. Различия в сельскохозяйственных практиках, существующие между регионами Камбоджи, где отмечается появление вируса Нипах, могут объяснять сложившуюся ситуацию и указывать на необходимые мероприятия с целью ограничения риска передачи вируса людям.Практикуемые людьми виды деятельности являются ключом к пониманию рисков, связанных с передачей новых инфекционных заболеваний. Социальные научные дисциплины, такие как антропология, должны быть включены в программы медицинского обслуживания, направленные на борьбу с новыми инфекционными заболеваниями. Поскольку летучие мыши являются переносчиками серьезных зоонозных патогенов, такие объединенные исследования могут способствовать снижению риска появления других заболеваний, передающихся через летучих мышей.

Rabies is endemic in Cambodia. For exposed humans, post-exposure prophylaxis (PEP) is very effective in preventing this otherwise fatal disease. The Institut Pasteur du Cambodge (IPC) in Phnom Penh was the primary distributor of PEP in Cambodia until 2018. Since then, and to increase distribution of PEP, two new centers have been opened by IPC in the provinces of Battambang and Kampong Cham. Data on bitten patients, who sometimes bring the head of the biting animal for rabies analyses, have been recorded by IPC since 2000. However, human cases are not routinely recorded in Cambodia, making it difficult to establish a human burden of disease and generate a risk map of dog bites to inform the selection of future PEP center locations in high-risk areas. Our aim was to assess the impact of accessibility to rabies centers on the yearly rate of PEP patients in the population and generate a risk map to identify the locations where new centers would be the most beneficial to the Cambodian population. To accomplish this, we used spatio-temporal Bayesian regression models with the number of PEP patients as the outcome. The primary exposure variable considered was travel time to the nearest IPC center. Secondary exposure variables consisted of travel time to a provincial capital and urban proportion of the population. Between 2000 and 2016, a total of 293,955 PEP patient records were identified. Our results showed a significant negative association between travel time to IPC and the rate of PEP patients: an increase in one hour travel time from the living location to IPC PEP centers leads to a reduction in PEP rate of 70% to 80%. Five provinces were identified as the most efficient locations for future centers to maximize PEP accessibility: Banteay Meanchey, Siem Reap, Takeo, Kampot and Svay Rieng. Adding a PEP center in every provincial capital would increase the proportion of Cambodians living within 60 minutes of a PEP center from 26.6% to 64.9%, and living within 120 minutes from 52.8% to 93.3%, which could save hundreds of lives annually.

International audience; Cambodia is a rabid-endemic country. However, data on dog population characteristics are lacking, and there is no national dog vaccination program. We implemented the first extensive door-to-door longitudinal survey in 2 Cambodian provinces, namely Kandal and Battambang, to estimate dog population demographic parameters, identify dog ownership determinants, analyze dog management practices and estimate the yearly cumulative bite incidence and associated factors. During the first session, more than 5000 dogs were recorded and identified. Data on families, dogs and cats characteristics, as well as the number of bites experienced the year before in the family, were recorded. One year later, a second session was performed in both provinces to record missing dogs and the reasons for missing. Age-specific survival rates of the dog populations were computed using Kaplan-Meier estimates. Ownership determinants and bite risk factors were identified using a negative binomial regression model. Dog trade and dog meat consumption were often reported. We estimated high dog-to-human ratios (1:3.8 in Kandal, and 1:3.3 in Battambang). The mean age of dog populations was 26.4 months in Kandal against 24.3 in Battambang, with a survival rate of 52% at 24 months in Kandal (34% only in Battambang). They were no feral dogs, but the large majority of recorded dogs were free roaming. In both provinces, the number of dogs significantly increased in families with children younger than 15, and when the head of the family was a male. The estimated yearly cumulative bite incidences were 2.3 and 3.1% in Kandal and Battambang provinces respectively, and are among the highest in the world. Our survey provides valuable data to focus information programs, parametrize transmission models and identify efficient vaccination strategies to control rabies in Cambodia in the future.

Japanese encephalitis virus (JEV) is the main cause of human viral encephalitis in Asia, with a mortality rate reaching 30%, mostly affecting children. The traditionally described cycle involving wild birds as reservoirs, pigs as amplifying hosts and Culex mosquitoes as vectors is questioned, with increasing evidence of a more complex multi-host system involved in areas where densities of pigs are low, such as in Cambodia. In 2018, we examined pigs, chickens, ducks and dogs from Kandal province, Cambodia, for antibody response against JEV by hemagglutination inhibition and virus neutralization assays. Forces of infection (FOI) for flaviviruses and JEV were estimated per species and per unit of body surface area (BSA). JEV seroprevalence reached 31% (95% CI: 23&ndash, 41%) in pigs, 1% (95% CI: 0.1&ndash, 3%) in chickens, 12% (95% CI: 7&ndash, 19%) in ducks and 35% (95% CI: 28&ndash, 42%) in dogs. Pigs were most likely to be infected (FOI: 0.09 per month), but the FOI was higher in ducks than in pigs for a given BSA (ratio of 0.13). Dogs had a lower FOI than ducks but a higher FOI than chickens (0.01 per month). For a given BSA, dogs were less likely to be infected than pigs (ratio of 1.9). In Cambodia, the virus may be circulating between multiple hosts. Dogs live in close contact with humans, and estimating their exposure to JEV infection could be a relevant indicator of the risk for humans to get infected, which is poorly known due to underdiagnosis. Understanding the JEV cycle and developing tools to quantify the exposure of humans is essential to adapt and support control measures for this vaccine-preventable disease.

International audience; The clinical presentation of dengue virus (DENV) infection is variable. Severe complications mainly result from exacerbated immune responses. Type I interferons (IFN-I) are important in antiviral responses and form a crucial link between innate and adaptive immunity. Their contribution to host defense during DENV infection remains under-studied, as direct quantification of IFN-I is challenging. We combined ultra-sensitive single-molecule array (Simoa) digital ELISA with IFN-I gene expression to elucidate the role of IFN-I in a well-characterized cohort of hospitalized Cambodian children undergoing acute DENV infection. Higher concentrations of type I IFN proteins were observed in blood of DENV patients, compared to healthy donors, and correlated with viral load. Stratifying patients for disease severity, we found a decreased expression of IFN-I in patients with a more severe clinical outcome, such as dengue hemorrhagic fever (DHF) or dengue shock syndrome (DSS). This was seen in parallel to a correlation between low IFNα protein concentrations and decreased platelet counts. Type I IFNs concentrations were correlated to frequencies of plasmacytoid DCs, not DENV-infected myloid DCs and correlated inversely with neutralizing anti-DENV antibody titers. Hence, type I IFN produced in the acute phase of infection is associated with less severe outcome of dengue disease.

International audience; Thirty-five human influenza A(H5N1) cases were reported in Cambodia during 2013-2014 after emergence of a clade 1.1.2 reassortant virus. We tested 881 villagers and found 2 cases of pauci- or asymptomatic infection. Seroprevalence after emergence of the reassortant strain (0.2%) was lower than the aggregate seroprevalence of 1.3% reported in earlier studies.

International audience; OBJECTIVES:This study aimed to investigate proteinuria occurring during dengue disease in children and assess if measurement of this parameter can help physicians in the clinical management of patients.METHODS:Proteinuria was assessed by dipstick and quantified by urine protein:creatinine ratio (UPCR) in samples from patients hospitalized with a confirmed dengue infection and in healthy controls.RESULTS:The dipstick tested positive in 42.9% of the patients presenting at hospital with dengue versus 20.0% in healthy controls. UPCR increased during the critical phase of the disease; peaking one week after fever onset then decreasing as the patients recovered. Patients with warnings signs or severe dengue were more likely to present with proteinuria detected by UPCR at the time of hospital admission compared to patients without warning signs. The sensitivity of this marker, however, was limited as only 16.1% of the patients with warning signs had proteinuria.CONCLUSIONS:Urine dipstick and UPCR do not seem to be very valuable for the triage of the patients at the time of the initial consultation but the observation of a decrease of the UPCR during the course of the illness appears to indicate an evolution towards recovery.

International audience; We describe a retrospective study on circulation of Zika virus in Cambodia during 2007-2016 among patients with dengue-like symptoms and Aedes aegypti mosquitoes. Our findings suggest that Zika virus in Cambodia belongs to the Asia genotype, is endemic, has low prevalence, and has had low-level impact on public health.

International audience; We investigated dengue virus (DENV) and asymptomatic DENV infections in rural villages of Kampong Cham Province, Cambodia, during 2012 and 2013. We conducted perifocal investigations in and around households for 149 DENV index cases identified through hospital and village surveillance. We tested participants 0.5–30 years of age by using nonstructural 1 rapid tests and confirmed DENV infections using quantitative reverse transcription PCR or nonstructural 1–capture ELISA. We used multivariable Poisson regressions to explore links between participants’ DENV infection status and household characteristics. Of 7,960 study participants, 346 (4.4%) were infected with DENV, among whom 302 (87.3%) were

International audience; Rabies causes 60,000 deaths worldwide annually. Rabies post-exposure prophylaxis is highly effective but often geographically and financially beyond reach in endemic developing countries. We conducted a retrospective study on clinical outcome at ≥6 months in 3318 Cambodians who received intradermal Vero cell vaccine post-exposure prophylaxis after a bite by a rabid or sick-looking but untested dog in 2003-2014. An external expert panel examined verbal autopsy reports to identify rabies deaths. 1739 (93.65%) persons bitten by rabid- and 1066 (72.96%) bitten by sick-looking but untested dogs were traced and 513 were lost to follow-up. Among the former, 1591 (91.49%) and 129 (7.42%) patients referred for 4+ and 3 post-exposure prophylaxis sessions, respectively. Three persons died of probable rabies so that the overall percentage of survival was 99.83% (95% exact confidence interval: 99.49-99.96%) in post-exposure prophylaxis recipients bitten by confirmed rabid dogs. No significant difference was found in survival among patients who received 3 vs. 4+ sessions (with or without rabies immunoglobin). The power of the study, however, was limited. The current four sessions/one month intradermal regimen can be reduced to a three sessions/one week at no detectable added risk to patients, with the limitation of study power at 49%. A clinical follow-up system should be adopted by rabies prevention centers, especially to monitor implementation of an abridged course. The Institut Pasteur in Cambodia regimen will improve vaccine equity by treating 33% more patients with available doses, reduce direct cost of vaccination, transportation and other indirect costs to vaccinees.

International audience; Postexposure prophylaxis (PEP) prevents human rabies and is accessible in Cambodia principally in Phnom Penh, the capital. Timely, affordable access to PEP is a challenge for the mainly rural population. We aimed to identify districts independently associated with PEP noncompletion to position frontline vaccination centers. We analyzed the 2009–2013 database at the Rabies Prevention Center at the Institut Pasteur du Cambodge, Phnom Penh. Logistic regressions identified nongeographic determinants of PEP noncompletion as well as the districts that were independently associated with noncompletion after adjustment for these determinants. The influence of distance by road was estimated using a boosted regression-trees model. We computed a population attributable fraction (rabies index (RI)) for each district and developed a map of this RI distribution. A cartographic analysis based on the statistic developed by Getis and Ord identified clusters of high-RI districts. Factors independently associated with noncompletion were pa-tients' district of residence, male sex, age 15–49 years, initial visit during rice harvest, the dog's status (culled or disappeared), and a prescribed PEP protocol requiring more than 3 PEP sessions (4 or 5). Four clusters of high-RI districts were identified using this analytical strategy, which is applicable to many vaccination or other health services. Positioning frontline PEP centers in these districts could significantly widen access to timely and adequate PEP.

International audience; Chikungunya virus (CHIKV) is an alphavirus circulating worldwide. Its presence in Asia has been reported since the 1950s, constituting the Asian genotype. Since 2005, strains from the Eastern, Central, and Southern African (ECSA) genotype have caused several outbreaks across Asia. Viruses from the ECSA genotype were also detected in Cambodia in late 2011 and led to an outbreak in a rural community in 2012. A former investigation from 2012 found a higher risk of infection in people younger than 40 years, suggesting a pre-existing herd immunity in the older Cambodian population due to infection with an Asian genotype. In 2016, we collected serum from equivalent numbers of individuals born before 1975 and born after 1980 that were also part of the 2012 study. We analyzed the 154 serum samples from 2016 for neutralization against the Cambodian ECSA isolate and three strains belonging to the Asian genotype. This experiment revealed that 22.5% (18/80) of the younger study participants had no CHIKV antibodies, whereas 5.4% (4/74) of the older population remained naive. Study participants infected during the ECSA outbreak had twofold neutralizing titers against the ECSA and the most ancient Asian genotype virus (Thailand 1958) compared to the other two Asian genotype viruses. The neutralization data also support the older population's exposure to an Asian genotype virus during the 1960s. The observed cross-reactivity confirms that the investigated CHIKV strains belong to a single serotype despite the emergence of novel ECSA genotype viruses and supports the importance of the development of a Chikungunya vaccine.

International audience; Longitudinal surveillance of 2 live bird markets in Cambodia revealed year-round, high co-circulation of H5, H7, and H9 influenza viruses. We detected influenza A viruses in 51.3% of ducks and 39.6% of chickens, and co-infections, mainly by H5 and H9 viruses, in 0.8% of ducks and 4.5% of chickens.

Background Authorities have pledged to eliminate canine rabies by 2020 in Cambodia, a country with a very high rabies burden. Logistic and financial access to timely and adequate postexposure prophylaxis (PEP) is essential for preventing rabies in humans. Methods We undertook a survey of the few identified sites where PEP rabies vaccination and rabies immunoglobulin (RIG) are available in Cambodia. We examined the Rabies Prevention Center at Institut Pasteur du Cambodge (rpc@ipc) database and rpc@ipc order forms for 2012 to assess vaccine and RIG use. We conducted a rapid internet survey of centers that provide rabies vaccine and RIG in Cambodia, other than rpc@ipc. Results The cost of a full course of intramuscular or intradermal PEP in Cambodia, with and without RIG, was also estimated. Rabies vaccination is free of charge in one foundation hospital and is accessible for a fee at Institut Pasteur du Cambodge (IPC), some institutions, and some Cambodian private clinics. In 2012, 27,500 rabies vaccine doses (0.5 mL) and 591 equine RIG doses were used to provide intradermal PEP to 20,610 persons at rpc@ipc following animal bites. Outside of rpc@ipc, an estimated total of 53,400 vaccine doses and 200 RIG doses were used in Cambodia in 2012. The wholesale cost of full rabies PEP was estimated at 50% to 100% of a Cambodian farmer's monthly wage. Conclusions Local populations and travelers cannot be sure to locally access adequate and timely PEP due to high costs and low access to RIG. Travelers to high-endemic areas such as Cambodia are strongly encouraged to undergo pre-exposure vaccination or seek expert advice, as per World Health Organization (WHO) recommendations. State-subsidized, pre-positioned stocks of human vaccine and RIG in bite management centers would extend the rabies prevention centers network. Support from Institut Pasteur du Cambodge for staff training, cold chain, and quality control would contribute to reducing the risk of rabies deaths in Cambodia.

Dengue dynamics are shaped by the complex interplay between several factors, including vector seasonality, interaction between four virus serotypes, and inapparent infections. However, paucity or quality of data do not allow for all of these to be taken into account in mathematical models. In order to explore separately the importance of these factors in models, we combined surveillance data with a local-scale cluster study in the rural province of Kampong Cham (Cambodia), in which serotypes and asymptomatic infections were documented. We formulate several mechanistic models, each one relying on a different set of hypotheses, such as explicit vector dynamics, transmission via asymptomatic infections and coexistence of several virus serotypes. Models are confronted with the observed time series using Bayesian inference, through Markov chain Monte Carlo. Model selection is then performed using statistical information criteria, and the coherence of epidemiological characteristics (reproduction numbers, incidence proportion, dynamics of the susceptible classes) is assessed in each model. Our analyses on transmission dynamics in a rural endemic setting highlight that two-strain models with interacting effects better reproduce the long term data, but they are difficult to parameterize when relying on incidence cases only. On the other hand, considering the available data, incorporating vector and asymptomatic components seems of limited added-value when seasonality and underreporting are already accounted for. Keywords: Model selection, Dengue, Vector borne disease, Mathematical model, Cambodia

International audience; BACKGROUND:Highly pathogenic avian influenza A (H5N1) virus has been of public health concern since 2003. Probable risk factors for A(H5N1) transmission to human have been demonstrated in several studies or epidemiological reports. However, transmission patterns may differ according to demographic characteristics of the population and local practices. This article aggregates these data from three studies with data collected in the previous surveys in 2006 and 2007 to further examine the risks factors associated with presence of anti-A(H5) antibodies among villagers residing within outbreak areas.METHODS:We aggregated 5-year data (2006-2010) from serology survey and matched case-control studies in Cambodia to further examine the risks factors associated with A(H5N1) infection among villagers in the outbreak areas.RESULTS:Serotesting among villagers detected 35 (1.5 % [0-2.6]) positive cases suggesting recent exposure to A(H5N1) virus. Practices associated with A(H5N1) infection among all ages were: having poultry cage or nesting area under or adjacent to the house (OR: 6.7 [1.6-28.3]; p = 0.010) and transporting poultry to market (OR: 17.6 [1.6-193.7]; p = 0.019). Practices found as risk factors for the infection among age under 20 years were swimming/bathing in ponds also accessed by domestic poultry (OR: 4.6 [1.1-19.1]; p = 0.038). Association with consuming wild birds reached borderline significance (p = 0.066).CONCLUSION:Our results suggest that swimming/bathing in contaminated pond water and close contact with poultry may present a risk of A(H5N1) transmission to human.

To estimate the 2009-2010 death rates, causes, and patterns of mortality in rural Cambodia, we conducted active, population-based death surveillance in 25 rural villages of Cambodia from March 2009 to August 2010. Among the population of 28 053 under surveillance, 280 deaths were reported and explored by physician-certified verbal autopsies, using the International Classification of Diseases 10, yielding an overall mortality rate (MR) of 6.7/1000 persons-year (95% CI 5.74-7.68). The MR was 39.1/1000 live births for those younger than 5 years old. Infants accounted for 5.4% of all deaths. In children younger than 5 years, infectious and parasitic diseases were the leading causes of death. In children 5 to 14 years, 3 out of 4 deaths were due to injuries. Adult deaths were mainly attributed to noncommunicable diseases (52%). We conclude that this rural population is facing a substantial burden of noncommunicable diseases while still struggling with infectious diseases, respiratory diseases in particular.

Lien vers le texte intégral : http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=pubmed&dopt=Abstract&list_uids=22677620; International audience; The Dengue National Control Program was established in Cambodia in 2000 and has reported between 10,000 and 40,000 dengue cases per year with a case fatality rate ranging from 0.7 to 1.7. In this study 39 DENV-2 and 57 DENV-3 viruses isolated from patients between 2000 and were fully sequenced. Five DENV2 and four DENV3 distinct lineages with different dynamics were identified. Each lineage was characterized by the presence of specific mutations with no evidence of recombination. In both DENV-2 and DENV-3 the lineages present prior to 2003 were replaced after that date by unrelated lineages. After 2003, DENV-2 lineages D2-3 and D2-4 cocirculated until 2007 when they were almost completely replaced by a lineage D2-5 which emerged from Conversely, all DENV-3 lineages remained, diversified and cocirculated with novel lineages emerging. Years 2006 and 2007 were marked by a high prevalence of DENV-3 and 2007 with a large dengue outbreak and a high proportion of patients with severe disease. Selective sweeps in DENV-1 and DENV-2 were linked to immunological escape to a predominately DENV-3-driven immunological response. The complex dynamic of dengue in Cambodia in the last ten years has been associated with a combination of stochastic climatic events, cocirculation, coevolution, adaptation to different vector populations, and with the human population immunological landscape.

International audience; Surveillance for avian influenza viruses (AIVs) in poultry and environmental samples was conducted in four live-bird markets in Cambodia from January through November 2013. Through real-time RT-PCR testing, AIVs were detected in 45% of 1048 samples collected throughout the year. Detection rates ranged from 32% and 18% in duck and chicken swabs, respectively, to 75% in carcass wash water samples. Influenza A/H5N1 virus was detected in 79% of samples positive for influenza A virus and 35% of all samples collected. Sequence analysis of full-length haemagglutinin (HA) and neuraminidase (NA) genes from A/H5N1 viruses, and full-genome analysis of six representative isolates, revealed that the clade 1.1.2 reassortant virus associated with Cambodian human cases during 2013 was the only A/H5N1 virus detected during the year. However, multiplex reverse transcriptase-polymerase chain reaction (RT-PCR) analysis of HA and NA genes revealed co-circulation of at least nine low pathogenic AIVs from HA1, HA2, HA3, HA4, HA6, HA7, HA9, HA10 and HA11 subtypes. Four repeated serological surveys were conducted throughout the year in a cohort of 125 poultry workers. Serological testing found an overall prevalence of 4.5% and 1.8% for antibodies to A/H5N1 and A/H9N2, respectively. Seroconversion rates of 3.7 and 0.9 cases per 1000 person-months participation were detected for A/H5N1 and A/H9N2, respectively. Peak AIV circulation was associated with the Lunar New Year festival. Knowledge of periods of increased circulation of avian influenza in markets should inform intervention measures such as market cleaning and closures to reduce risk of human infections and emergence of novel AIVs.

International audience; BACKGROUND:Leptospirosis is an emerging but neglected public health challenge in the Asia/Pacific Region with an annual incidence estimated at 10-100 per 100,000 population. No accurate data, however, are available for at-risk rural Cambodian communities.METHOD:We conducted anonymous, unlinked testing for IgM antibodies to Leptospira spp. on paired sera of Cambodian patients

International audience; Three-quarters of the estimated 390 million dengue virus (DENV) infections each year are clinically inapparent. People with inapparent dengue virus infections are generally considered dead-end hosts for transmission because they do not reach sufficiently high viremia levels to infect mosquitoes. Here, we show that, despite their lower average level of viremia, asymptomatic people can be infectious to mosquitoes. Moreover, at a given level of viremia, DENV-infected people with no detectable symptoms or before the onset of symptoms are significantly more infectious to mosquitoes than people with symptomatic infections. Because DENV viremic people without clinical symptoms may be exposed to more mosquitoes through their undisrupted daily routines than sick people and represent the bulk of DENV infections, our data indicate that they have the potential to contribute significantly more to virus transmission to mosquitoes than previously recognized.

SUMMARYRobust disease burden estimates are important for decision-making concerning introduction of new vaccines. Dengue is a major public health problem in the tropics but robust disease burden estimates are lacking. We conducted a two-sample, capture–recapture study in the largest province in Cambodia to determine disease under-recognition to the National Dengue Surveillance System (NDSS). During 2006–2008, community-based active surveillance for acute febrile illness was conducted in 0- to 19-year-olds in rural and urban areas combined with testing for dengue virus infection. Of 14 354 individuals under active surveillance (22 498 person-seasons), the annual incidence ranged from 13·4 to 57·8/1000 person-seasons. During the same period, NDSS incidence rates ranged from 1·1/1000 to 5·7/1000, which was 3·9- to 29·0-fold lower than found in the capture–recapture study. In hospitalized cases, the rate of under-recognition was 1·1- to 2·4-fold. This study shows the substantial degree of under-recognition/reporting of dengue and that reported hospitalized cases are not a good surrogate for estimating dengue disease burden.

Background Dengue laboratory diagnosis is essentially based on detection of the virus, its components or antibodies directed against the virus in blood samples. Blood, however, may be difficult to draw in some patients, especially in children, and sampling during outbreak investigations or epidemiological studies may face logistical challenges or limited compliance to invasive procedures from subjects. The aim of this study was to assess the possibility of using saliva and urine samples instead of blood for dengue diagnosis. Methodology/Principal Findings Serial plasma, urine and saliva samples were collected at several time-points between the day of admission to hospital until three months after the onset of fever in children with confirmed dengue disease. Quantitative RT-PCR, NS1 antigen capture and ELISA serology for anti-DENV antibody (IgG, IgM and IgA) detection were performed in parallel on the three body fluids. RT-PCR and NS1 tests demonstrated an overall sensitivity of 85.4%/63.4%, 41.6%/14.5% and 39%/28.3%, in plasma, urine and saliva specimens, respectively. When urine and saliva samples were collected at the same time-points and tested concurrently, the diagnostic sensitivity of RNA and NS1 detection assays was 69.1% and 34.4%, respectively. IgG/IgA detection assays had an overall sensitivity of 54.4%/37.4%, 38.5%/26.8% and 52.9%/28.6% in plasma, urine and saliva specimens, respectively. IgM were detected in 38.1% and 36% of the plasma and saliva samples but never in urine. Conclusions Although the performances of the different diagnostic methods were not as good in saliva and urine as in plasma specimens, the results obtained by qRT-PCR and by anti-DENV antibody ELISA could well justify the use of these two body fluids to detect dengue infection in situations when the collection of blood specimens is not possible., Author Summary Dengue is the most important arthropod-borne disease affecting humans and represents a huge public health burden in affected countries. Symptoms are often non-specific hence the need for an early, sensitive and specific diagnosis of dengue for appropriate management as well as for early epidemic detection. Currently, almost all laboratory diagnostic methods require a blood specimen that may be sometimes be difficult or inconvenient to obtain. In this study, we assessed the possibility to use saliva and urine samples as alternatives to blood specimens in dengue diagnosis. We demonstrated that the performances of the different diagnostic methods (RT-PCR, NS1 antigen detection and anti-DENV IgM/IgG/IgA ELISAs) were in general not as good in saliva and urine as in plasma, but that the use of these body fluids obtained by non-invasive methods could be of value in certain circumstances such as outbreak investigations or in young children (once they are old enough to comply to instructions), in addition to the situations when blood cannot be easily collected (e.g., lack of phlebotomist, refusal of the procedure, etc.).

To determine potential risk for bird-to-human transmission during influenza A virus (H5N1) outbreaks among backyard poultry in rural Cambodia, we collected environmental specimens. Viral RNA was detected in 27 (35%) of 77 specimens of mud, pond water, water plants, and soil swabs. Our results underscore the need for regular disinfection of poultry areas.

Background Lopinavir/ritonavir (LPV/r) is widely used in Cambodia with high efficacy but scarce data exist on long-term metabolic toxicity. Methods We carried out a cross-sectional and retrospective study evaluating metabolic disorders and cardiovascular risk in Cambodian patients on LPV/r-based antiretroviral therapy (ART) for > 1 year followed in Calmette Hospital, Phnom Penh. Data collected included cardiovascular risk factors, fasting blood lipids and glucose, and retrospective collection of bioclinical data. We estimated the 10-year risks of coronary heart disease with the Framingham, Ramathibodi-Electricity Generating Authority of Thailand (Rama-EGAT), and the Data Collection on Adverse Effects of Anti-HIV Drugs (D:A:D) risk equations. We identified patients with LDL above targets defined by the French expert group on HIV and by the HIV Medicine Association of the Infectious Disease Society of America and the Adult AIDS Clinical Trials Group (IDSA-AACTG). Results Of 115 patients enrolled—mean age 40.9 years, 69.2% male, mean time on LPV/r 3.8 years—40 (34.8%) had hypercholesterolemia (> 2.40 g/L), and 69 (60.0%) had low HDL cholesterol (< 0.40 g/L). Twelve (10.5%), 28 (24%) and 9 (7.7%) patients had a 10-year risk of coronary heart disease ≥ 10% according to the Framingham, D:A:D, and Rama-EGAT score, respectively. Fifty one (44.4%) and 36 (31.3%) patients had not reached their LDL target according to IDSA-AACTG and French recommendations, respectively. Conclusion Prevalence of dyslipidemia was high in this cohort of HIV-infected Cambodian patients on LPV/r. Roughly one third had high LDL levels requiring specific intervention.

International audience; A case of confirmed rabies in a French resident is a wake-up call for improved access to timely and adequate rabies post-exposure prophylaxis for all those living in Cambodia, as well as for improved pre-exposure prevention in travellers to Cambodia and other highly endemic settings.

Please cite this paper as: Arnott et al. (2013) Human bocavirus amongst an all-ages population hospitalised with acute lower respiratory infections in Cambodia. Influenza and Other Respiratory Viruses 7(2) 201–210. Background Human bocavirus (HBoV) is a novel parvovirus that is associated with respiratory and gastrointestinal tract disease. Objectives To investigate the prevalence and genetic diversity of HBoV amongst hospitalized patients with acute lower respiratory infection (ALRI) in Cambodia. Study Design Samples were collected from 2773 patients of all ages hospitalised with symptoms of ALRI between 2007 and 2009. All samples were screened by multiplex RT-PCR/PCR for 18 respiratory viruses. All samples positive for HBoV were sequenced and included in this study. Results Of the samples tested, 43 (1·5%) were positive for HBoV. The incidence of HBoV did not vary between the consecutive seasons investigated, and HBoV infections were detected year-round. The incidence of HBoV infection was highest in patients aged

Background Disease incidence data are needed to guide decision-making for public health interventions. Although dengue is a reportable disease in Thailand and Cambodia, the degree that reported incidence underrecognizes true disease burden is unknown. We utilized dengue incidence calculated from laboratory-confirmed outpatient and inpatient cases in prospective cohort studies to estimate the magnitude of dengue underrecognition and to establish more accurate disease burden estimates for these countries. Methods and Findings Cohort studies were conducted among children aged 95,000 children in Thailand and >58,000 children in Cambodia were estimated to be hospitalized due to dengue. Conclusion Calculating MFs by comparing prospective cohort study data to locally-reported national surveillance data is one approach to more accurately assess disease burden. These data indicate that although dengue is regularly reported in many countries, national surveillance data significantly underrecognize the true burden of disease., Author Summary Dengue is a major public health problem especially in tropical and subtropical countries of Asia and Latin-America. An effective dengue vaccine is not yet available, but several vaccine candidates are currently being evaluated in clinical trials. Accurate country-level incidence data are crucial to assess the cost-effectiveness of such vaccines and will assist policy-makers in making vaccine introduction decisions. Existing national surveillance systems are often passive and are designed to monitor trends and to detect disease outbreaks. Our analyses of data from prospectively followed cohorts with laboratory confirmation of dengue cases show that, in Thailand and Cambodia, dengue incidence is underrecognized by more than 8-fold. The magnitude of the outpatient burden caused by dengue is not assessed or reflected by the national surveillance data. We estimate that a median of more than 340,000 symptomatic dengue virus infections occurred annually in children less than 15 years of age in Thailand in Cambodia between 2003 and 2007.

Background Dengue vaccines are now in late-stage development, and evaluation and robust estimates of dengue disease burden are needed to facilitate further development and introduction. In Cambodia, the national dengue case-definition only allows reporting of children less than 16 years of age, and little is known about dengue burden in rural areas and among older persons. To estimate the true burden of dengue in the largest province of Cambodia, Kampong Cham, we conducted community-based active dengue fever surveillance among the 0-to-19–year age group in rural villages and urban areas during 2006–2008. Methods and Findings Active surveillance for febrile illness was conducted in 32 villages and 10 urban areas by mothers trained to use digital thermometers combined with weekly home visits to identify persons with fever. An investigation team visited families with febrile persons to obtain informed consent for participation in the follow-up study, which included collection of personal data and blood specimens. Dengue-related febrile illness was defined using molecular and serological testing of paired acute and convalescent blood samples. Over the three years of surveillance, 6,121 fever episodes were identified with 736 laboratory-confirmed dengue virus (DENV) infections for incidences of 13.4–57.8/1,000 person-seasons. Average incidence was highest among children less than 7 years of age (41.1/1,000 person-seasons) and lowest among the 16-to-19–year age group (11.3/1,000 person-seasons). The distribution of dengue was highly focal, with incidence rates in villages and urban areas ranging from 1.5–211.5/1,000 person-seasons (median 36.5). During a DENV-3 outbreak in 2007, rural areas were affected more than urban areas (incidence 71 vs. 17/1,000 person-seasons, p, Author Summary Dengue is a major public health problem in South-East Asia. Several dengue vaccine candidates are now in late-stage development and are being evaluated in clinical trials. Accurate estimates of true dengue disease burden will become an important factor in the public-health decision-making process for endemic countries once safe and effective vaccines become available. However, estimates of the true disease incidence are difficult to make, because national surveillance systems suffer from disease under-recognition and reporting. Dengue is mainly reported among children, and in some countries, such as Cambodia, the national case definition only includes hospitalized children. This study used active, community-based surveillance of febrile illness coupled with laboratory testing for DENV infection to identify cases of dengue fever in rural and urban populations. We found a high burden of dengue in young children and late adolescents in both rural and urban communities at a magnitude greater than previously described. The study also confirmed the previously observed focal nature of dengue virus transmission.

Background Since 2005, eight patients with H5N1 infection were laboratory confirmed in Cambodia. Despite the widespread of highly pathogenic avian influenza H5N1 virus and the intense exposure to poultry, there is growing evidence that H5N1 viruses may not be easily transmitted to human. Objectives To evaluate the frequency of H5N1 transmission in rural Cambodia, to identify potential risk factors for H5N1 in humans and to explore the extent of asymptomatic and clinically mild illness among humans. Study design A seroepidemiologic survey was conducted, 9 weeks after the recognition that H5N1 infection caused the death of a 13 years old female in April 2007. Blood specimens were collected from 700 participants for H5N1 serological testing. All participants were interviewed with standardized questionnaire to collect information about poultry exposure. Results Eighteen (2.6%) of the 700 villagers were tested positive cases for H5N1 antibodies. These 18 individuals were more likely than seronegative participants to report bathing or swimming in the community pond (p = 0.04). Conclusions The seroprevalence of H5N1 antibodies was higher than previously reported in the other investigations conducted in Cambodia and Thailand. This finding reinforces the overwhelming evidence that the virus continues to circulate widely in settings where human have high exposure to poultry. Our results, provides additional evidence suggesting that bathing or swimming in the community ponds, remains important potential risk factor for H5N1 infection. Both wild birds and domestic poultry have free access to these ponds which are also used for aquaculture through the dumping of poultry feces for fish feeding.

Background Since 2004, 21 highly pathogenic avian influenza H5N1 outbreaks in domestic poultry and eight human cases have been confirmed in Cambodia. As a result, a large number of avian influenza education campaigns have been ongoing in provinces in which H5N1outbreaks have occurred in humans and/or domestic poultry. Methodology/Principal Findings Data were collected from 1,252 adults >15 years old living in two southern provinces in Cambodia where H5N1 has been confirmed in domestic poultry and human populations using two cross-sectional surveys conducted in January 2006 and in November/December 2007. Poultry handling behaviors, poultry mortality occurrence and self-reported notification of suspect H5N1 poultry cases to animal health officials in these two surveys were evaluated. Our results demonstrate that although some at risk practices have declined since the first study, risky contact with poultry is still frequent. Improved rates of reporting poultry mortality were observed overall, but reporting to trained village animal health workers decreased by approximately 50%. Conclusions/Significance Although some improvements in human behavior have occurred, there are still areas—particularly with respect to the handling of poultry among children and the proper treatment of poultry and the surrounding household environment—that need to be addressed in public health campaigns. Though there were some differences in the sampling methods of the 2006 and 2007 surveys, our results illustrate the potential to induce considerable, potentially very relevant, behavioral changes over a short period of time.

BACKGROUND: We conducted investigations in 2 villages in Cambodia where outbreaks of influenza H5N1 occurred among humans and poultry to determine the frequency of and risk factors for H5N1 virus transmission. METHODS: During May 2006, approximately 7 weeks after outbreaks of influenza H5N1 among poultry occurred, villagers living near households of 2 patients with influenza H5N1 were interviewed about potential H5N1 exposures and had blood samples obtained for H5N1 serological testing by microneutralization assay. A seropositive result was defined as an influenza H5N1 neutralizing antibody titer of 1:80, with confirmation by Western blot assay. A case-control study was conducted to identify risk factors for influenza H5N1 virus infection. Control subjects, who had seronegative results of tests, were matched with H5N1-seropositive persons by village residence, households with an influenza H5N1-infected poultry flock, sex, and age. RESULTS: Seven (1.0%) of 674 villagers tested seropositive for influenza H5N1 antibodies and did not report severe illness; 6 (85.7%) were male. The 7 H5N1-seropositive persons, all of whom were aged

BackgroundThe Cambodian National Influenza Center (NIC) monitored and characterized circulating influenza strains from 2009 to 2011.Methodology/principal findingsSentinel and study sites collected nasopharyngeal specimens for diagnostic detection, virus isolation, antigenic characterization, sequencing and antiviral susceptibility analysis from patients who fulfilled case definitions for influenza-like illness, acute lower respiratory infections and event-based surveillance. Each year in Cambodia, influenza viruses were detected mainly from June to November, during the rainy season. Antigenic analysis show that A/H1N1pdm09 isolates belonged to the A/California/7/2009-like group. Circulating A/H3N2 strains were A/Brisbane/10/2007-like in 2009 before drifting to A/Perth/16/2009-like in 2010 and 2011. The Cambodian influenza B isolates from 2009 to 2011 all belonged to the B/Victoria lineage represented by the vaccine strains B/Brisbane/60/2008 and B/Malaysia/2506/2004. Sequences of the M2 gene obtained from representative 2009-2011 A/H3N2 and A/H1N1pdm09 strains all contained the S31N mutation associated with adamantanes resistance except for one A/H1N1pdm09 strain isolated in 2011 that lacked this mutation. No reduction in the susceptibility to neuraminidase inhibitors was observed among the influenza viruses circulating from 2009 to 2011. Phylogenetic analysis revealed that A/H3N2 strains clustered each year to a distinct group while most A/H1N1pdm09 isolates belonged to the S203T clade.Conclusions/significanceIn Cambodia, from 2009 to 2011, influenza activity occurred throughout the year with peak seasonality during the rainy season from June to November. Seasonal influenza epidemics were due to multiple genetically distinct viruses, even though all of the isolates were antigenically similar to the reference vaccine strains. The drug susceptibility profile of Cambodian influenza strains revealed that neuraminidase inhibitors would be the drug of choice for influenza treatment and chemoprophylaxis in Cambodia, as adamantanes are no longer expected to be effective.

Following almost 30 years of relative silence, chikungunya fever reemerged in Kenya in 2004. It subsequently spread to the islands of the Indian Ocean, reaching Southeast Asia in 2006. The virus was first detected in Cambodia in 2011 and a large outbreak occurred in the village of Trapeang Roka Kampong Speu Province in March 2012, in which 44% of the villagers had a recent infection biologically confirmed. The epidemic curve was constructed from the number of biologically-confirmed CHIKV cases per day determined from the date of fever onset, which was self-reported during a data collection campaign conducted in the village after the outbreak. All individuals participating in the campaign had infections confirmed by laboratory analysis, allowing for the identification of asymptomatic cases and those with an unreported date of fever onset. We develop a stochastic model explicitly including such cases, all of whom do not appear on the epidemic curve. We estimate the basic reproduction number of the outbreak to be 6.46 (95% C.I. [6.24, 6.78]). We show that this estimate is particularly sensitive to changes in the biting rate and mosquito longevity. Our model also indicates that the infection was more widespread within the population on the reported epidemic start date. We show that the exclusion of asymptomatic cases and cases with undocumented onset dates can lead to an underestimation of the reproduction number which, in turn, could negatively impact control strategies implemented by public health authorities. We highlight the need for properly documenting newly emerging pathogens in immunologically naive populations and the importance of identifying the route of disease introduction., Author Summary During the recent resurgence of chikungunya, the scale of imported cases into previously unaffected countries has caused great concern due to the presence of a competent vector (Aedes albopictus) in many of these regions. This study describes a mathematical model for a chikungunya outbreak in the rural Cambodian village of Trapeang Roka, where a chikungunya epidemic was recorded and documented in March 2012. The outbreak data is unique, in that all infections were confirmed by laboratory analysis, enabling the identification of asymptomatic individuals, in addition to individuals who failed to report details of their infection. A stochastic model, partitioning the infectious population into three distinct classes, is implemented using Gillespie's algorithm. We show that the incorporation of both biologically-confirmed symptomatic cases undocumented by date of fever onset and asymptomatic cases yields a higher estimate of the reproduction number. Our results highlight how reproduction numbers could be underestimated by limiting analysis to the epidemic curve. Carefully documenting cases and performing laboratory testing in cluster regions, such as the village considered here, could provide a more comprehensive insight into the true infection dynamics.

International audience; BACKGROUND: Few data exist on viral and bacterial etiology of acute lower respiratory infections (ALRI) in ≥ 5 year -old persons in the tropics. METHODS: We conducted active surveillance of community-acquired ALRI in two hospitals in Cambodia, a low-income tropical country. Patients were tested for acid-fast bacilli (AFB) by direct sputum examination, other bacteria by blood and/or sputum cultures, and respiratory viruses using molecular techniques on nasopharyngeal/throat swabs. Pulmonologists reviewed clinical/laboratory data and interpreted chest X-rays (CXR) to confirm ALRI. RESULTS: Between April 2007 - December 2009, 1,904 patients aged ≥5 years were admitted with acute pneumonia (50.4%), lung sequelae-associated ALRI (24.3%), isolated pleural effusions (8.9%) or normal CXR-related ALRI (17.1%); 61 (3.2%) died during hospitalization. The two former diagnoses were predominantly due to bacterial etiologies while viral detection was more frequent in the two latter diagnoses. AFB-positive accounted for 25.6% of acute pneumonia. Of the positive cultures (16.8%), abscess-prone Gram-negative bacteria (39.6%) and Haemophilus influenzae (38.0%) were most frequent, followed by Streptococcus pneumoniae (17.7%). Of the identified viruses, the three most common viruses included rhinoviruses (49.5%), respiratory syncytial virus (17.7%) and influenza viruses (12.1%) regardless of the diagnostic groups. Wheezing was associated with viral identification (31.9% vs. 13.8%, p < 0.001) independent of age and time-to-admission. CONCLUSIONS: High frequency of H. influenzae and S. pneumoniae infections support the need for introduction of the respective vaccines in the national immunization program. Tuberculosis was frequent in patients with acute pneumonia, requiring further investigation. The relationship between respiratory viruses and wheezing merits further studies.

Wet markets are common in many parts of the world and may promote the emergence, spread and maintenance of livestock pathogens, including zoonoses. A survey was conducted in order to assess the potential of Vietnamese and Cambodian live bird markets (LBMs) to sustain circulation of highly pathogenic avian influenza virus subtype H5N1 (HPAIV H5N1). Thirty Vietnamese and 8 Cambodian LBMs were visited, and structured interviews were conducted with the market managers and 561 Vietnamese and 84 Cambodian traders. Multivariate and cluster analysis were used to construct a typology of traders based on their poultry management practices. As a result of those practices and large poultry surplus (unsold poultry reoffered for sale the following day), some poultry traders were shown to promote conditions favorable for perpetuating HPAIV H5N1 in LBMs. More than 80% of these traders operated in LBMs located in the most densely populated areas, Ha Noi and Phnom Penh. The profiles of sellers operating at a given LBM could be reliably predicted using basic information about the location and type of market. Consequently, LBMs with the largest combination of risk factors for becoming virus reservoirs could be easily identified, potentially allowing control strategies to be appropriately targeted. These findings are of particular relevance to resource-scarce settings with extensively developed LBM systems, commonly found in South-East Asia.

Background Rabies, a fatal but preventable zoonosis, is a major public health problem in developing countries. In Cambodia the disease burden is largely underestimated because patients with encephalitis following dog bites are rarely hospitalized and die at home. Since 1998 Institut Pasteur in Cambodia (IPC), Phnom Penh has been the only source of free post-exposure prophylaxis (PEP) and post-mortem diagnosis. Methods The 1998–2007 data compiled by IPC was analyzed to describe all treated patients for PEP, results of human testing and confirmed rabies cases, and results of animal testing. From dog bites' characteristics, we defined a suspected rabid dog bite injury (SRDBI) in humans as a bite that was unprovoked, from a dog that died spontaneously, or from a dog that was reported sick. We applied a deterministic probability model to estimate 2007 rabies human mortality nationwide from the estimated incidence of rabid dog bites, the body distribution of bite wounds, and the probability of PEP access. Results During 1998–2007, 124,749 patients received PEP at IPC (average 12,470; range 8,907–14,475), and 63 fatal human cases presenting with encephalitis following a dog bite were reported, in which 73% were confirmed positive for rabies by direct immunofluorescence assay or by reverse-transcriptase polymerase chain reaction. During 1998–2007, IPC tested 1,255 animal brain samples; 1,214 (97%) were from dogs including 610 (49%) positive samples. In 2007, 14,475 patients received PEP (100 PEP/100,000 people in Cambodia) including 95% who resided in Phnom Penh (615 PEP/100,000) or five neighboring provinces. The predictive model estimated 810 human rabies deaths would occur in 2007 (95%confidence interval [CI] 394–1,607), an incidence of 5.8/100,000 (95% CI 2.8–11.5). Conclusions Access to PEP is only sufficient for Phnom Penh residents. In 2007, the estimated rabies related mortality exceeded that of malaria and that of dengue. A national rabies control program is needed to improve surveillance and access to PEP, and to initiate vaccination campaigns in dogs., Author Summary In Cambodia, rabies still elicits fear in the communities. Since 1998 the Institut Pasteur in Cambodia (IPC), Phnom Penh has been the only source of free post-exposure prophylaxis (PEP) and post mortem diagnosis. During 1998–2007, on average ∼12,400 patients received PEP annually at IPC (range 8,907–14,475) and 63 fatal human cases presenting with encephalitis following a dog bite were reported including 73% who tested positive by fluorescent-antibody test on brain samples or/and by reverse-transcriptase polymerase chain reaction on skin, cerebrospinal fluid, or urine. In 2007, 14,475 patients received PEP (100 PEP/100,000 people in Cambodia) including 95% who resided in Phnom Penh city (615 PEP/100,000) or five neighboring provinces. Using a step-by-step probability model, we estimated that 810 human rabies deaths would occur in 2007 (95% confidence interval [CI] 394–1,607); an incidence of 5.8/100,000 (95%CI 2.8–11.5). As a result, despite high attendance at the IPC's PEP center most Cambodians living in peripheral provinces in Cambodia may not have adequate access to PEP. Finally, the model generated one of the highest incidences of rabies worldwide. A national rabies control program is needed to improve surveillance and access to PEP, and to initiate vaccination campaigns in dogs.