New frontiers in applied veterinary point‐of‐capture diagnostics: Toward early detection and control of zoonotic influenza

Among the chief limitations in achieving early detection and control of animal‐origin influenza of pandemic potential in high‐risk livestock populations is the existing lag time between sample collection and diagnostic result. Advances in molecular diagnostics are permitting deployment of affordable, rapid, highly sensitive, and specific point‐of‐capture assays, providing opportunities for targeted surveillance driving containment strategies with potentially compelling returns on investment. Interrupting disease transmission at source holds promise of disrupting cycles of animal‐origin influenza incursion to endemicity and limiting impact on animal production, food security, and public health. Adoption of new point‐of‐capture diagnostics should be undertaken in the context of promoting robust veterinary services systems and parallel support for operationalizing pre‐authorized plans and communication strategies that will ensure that the full potential of these new platforms is realized.     

Respiratory and skin health among glass microfiber production workers: a cross-sectional study

Background  

Only a few studies have investigated non-malignant respiratory effects of glass microfibers and these have provided inconsistent results. Our objective was to assess the effects of exposure to glass microfibers on respiratory and skin symptoms, asthma and lung function.     

Transmission of the highly pathogenic avian influenza virus H5N1 within flocks during the 2004 epidemic in Thailand

This present study is the first to quantify the transmission of avian influenza virus H5N1 within flocks during the 2004 epidemic in Thailand. It uses the flock-level mortality data to estimate the transmission-rate parameter ( beta ) and the basic reproduction number (R(0)). The point estimates of beta varied from 2.26/day (95% confidence interval [CI], 2.01-2.55) for a 1-day infectious period to 0.66/day (95% CI, 0.50-0.87) for a 4-day infectious period, whereas the accompanying R(0) varied from 2.26 (95% CI, 2.01-2.55) to 2.64 (95% CI, 2.02-3.47). Although the point estimates of beta of backyard chickens and fighting cocks raised together were lower than those of laying hens and broiler chickens, this difference was not statistically significant. These results will enable us to assess the control measures in simulation studies. They also indicate that, for the elimination of the virus, a critical proportion of the susceptible poultry population in a flock (i.e., 80% of the population) needs to be vaccinated.     

Cost-Utility Analysis of Dasatinib and Nilotinib in Patients With Chronic Myeloid Leukemia Refractory to First-Line Treatment With Imatinib in Thailand

Background

Recently, the second-generation tyrosine kinase inhibitors dasatinib and nilotinib have emerged as alternative treatments in patients with chronic myeloid leukemia (CML) who are resistant to or intolerant of imatinib.

Objective

This article aimed to assess the cost utility and budget impact of using dasatinib or nilotinib, rather than high-dose (800-mg/d) imatinib, in patients with chronic phase (CP) CML who are resistant to standard-dose (400-mg/d) imatinib in Thailand.

Methods

A Markov simulation model was developed and used to estimate the lifetime costs and outcomes of treating patients aged ≥38 years with CP-CML. The efficacy parameters were synthesized from a systematic review. Utilities using the European Quality of Life–5 Dimensions tool and costs were obtained from the Thai CML population. Costs and outcomes were compared and presented as the incremental cost-effectiveness ratio in 2011 Thai baht (THB) per quality-adjusted life year (QALY) gained. One-way and probabilistic sensitivity analyses were performed to estimate parameter uncertainty.

Results

From a societal perspective, treatment with dasatinib was found to yield more QALYs (2.13) at a lower cost (THB 1,631,331) per person than high-dose imatinib. Nilotinib treatment was also found to be more cost-effective than high-dose imatinib, producing an incremental cost-effectiveness ratio of THB 83,328 per QALY gained. This treatment option also resulted in the highest number of QALYs gained of all of the treatment options. The costs of providing dasatinib, nilotinib, and high-dose imatinib were estimated at THB 5 billion, THB 6 billion, and THB 7 billion, respectively.

Conclusions

Treatment with dasatinib or nilotinib is likely to be more cost-effective than treatment with high-dose imatinib in CP-CML patients who do not respond positively to standard-dose imatinib in the Thai context. Dasatinib was found to be more cost-effective than nilotinib.     

Anxiety and Depression among Patients with Uveitis and Ocular Inflammatory Disease at a Tertiary Center in Southern Thailand: Vision-Related Quality of Life,Sociodemographics, and Clinical Characteristics Associated

Purpose: To estimate the prevalence of positive anxiety and depression screening in patients with ocular inflammatory disease (OID). The predictors associated with anxiety and depressive symptoms were investigated.

Methods: A cross-sectional study was conducted. The Thai Hospital Anxiety and Depression Scale (HADS), a sociodemographic questionnaire, and the Thai Visual Functioning Questionnaire 28 were administered to all participants. Associations were estimated using the Cox regression.

Results: Of the 86 participants, 12.8% and 8.1% screened positive for anxiety and depression, respectively. Predictors of an increase in both HADS-Anxiety and HADS-Depression scores comprised poor understanding of OIDs [adjusted relative probability (aRP) = 1.56; p = 0.021 and 1.59; p = 0.012, respectively], and low overall composite score (aRP = 1.45; p = 0.022 and 1.6; p = 0.002, respectively).

Conclusions: Approximately one-tenth of our patients screened positive for anxiety and depression. Patients with poor understanding of their OID and poor self-reported visual function were at an increased risk.     

Respondent-driven sampling to assess characteristics and estimate the number of injection drug users in Bangkok, Thailand

BACKGROUND: Since early in Thailand's HIV epidemic, HIV seroprevalence among injection drug users (IDUs) in Bangkok has been around 40%. As Thailand moves to strengthen HIV prevention and care programs for Bangkok IDUs, information on current patterns of drug use and an estimate of the size and composition of the IDU population are essential. METHODS: We used respondent-driven sampling (RDS) to recruit Bangkok IDUs who reported injecting in the past 6 months. IDUs were interviewed with a standardized questionnaire. Logistic regression was used to compare IDUs currently or previously in treatment with those never treated. RDS software was used to estimate IDU population size based on the proportion in treatment. RESULTS: Of 963 IDUs recruited, 828 (86%) were men. One hundred and twelve IDUs (12%) reported never having attended a drug treatment clinic. Young age, unemployment, injection of single drug, and never having been HIV tested were significantly associated with never-in-treatment status. The estimated proportion of IDUs in treatment was 0.55 (95% confidence interval, 0.52-0.60). Dividing the known number of IDUs in treatment (1981 IDUs attending Bangkok drug treatment clinics during October 2003 through March 2004) by this proportion, we estimated the number of IDUs in Bangkok during the period of RDS to be 3595 (95% confidence interval, 3296-3810). CONCLUSIONS: Data obtained through RDS, although subject to limitations from co-existing government drug control policies and possible under-recruitment of out-of-treatment IDUs, will be useful in informing policy, strengthening prevention approaches, and improving methods to monitor the HIV epidemic among Thai IDUs.     

Incidence Rate and Risk Factors for Contralateral Eye Involvement among Patients with AIDS and Cytomegalovirus Retinitis Treated with Local Therapy

Purpose: To calculate the incidence of, and to identify the risk factors for developing contralateral eye involvement among patients with AIDS and unilateral cytomegalovirus retinitis (CMV retinitis), who were treated, in the era of highly-active antiretroviral therapy (HAART), with repetitive intravitreal ganciclovir injections.

Materials and Methods: The clinical records of 119 patients were included. The main outcome measurement was the occurrence of contralateral eye involvement.

Results: Over a mean follow-up period of 1.6 years, the overall incidence rate of contralateral involvement was 0.17/person-year. The cumulative incidence of contralateral involvement at 6 months and 1 year was 23.8% and 28.4%, respectively. Receiving HAART at the visit before the event was associated with a decreased risk of developing contralateral retinitis (hazard ratio [HR]?=?0.26, P?=?0.002).

Conclusions: The use of HAART, associated with subsequent immune recovery, significantly reduced the incidence of contralateral eye involvement by approximately 75% among patients in our setting.     

Mapping H5N1 highly pathogenic avian influenza risk in Southeast Asia

The highly pathogenic avian influenza (HPAI) H5N1 virus that emerged in southern China in the mid-1990s has in recent years evolved into the first HPAI panzootic. In many countries where the virus was detected, the virus was successfully controlled, whereas other countries face periodic reoccurrence despite significant control efforts. A central question is to understand the factors favoring the continuing reoccurrence of the virus. The abundance of domestic ducks, in particular free-grazing ducks feeding in intensive rice cropping areas, has been identified as one such risk factor based on separate studies carried out in Thailand and Vietnam. In addition, recent extensive progress was made in the spatial prediction of rice cropping intensity obtained through satellite imagery processing. This article analyses the statistical association between the recorded HPAI H5N1 virus presence and a set of five key environmental variables comprising elevation, human population, chicken numbers, duck numbers, and rice cropping intensity for three synchronous epidemic waves in Thailand and Vietnam. A consistent pattern emerges suggesting risk to be associated with duck abundance, human population, and rice cropping intensity in contrast to a relatively low association with chicken numbers. A statistical risk model based on the second epidemic wave data in Thailand is found to maintain its predictive power when extrapolated to Vietnam, which supports its application to other countries with similar agro-ecological conditions such as Laos or Cambodia. The model's potential application to mapping HPAI H5N1 disease risk in Indonesia is discussed.     

Incidence Rates and Risk Factors for Vision Loss among AIDS-Related Cytomegalovirus Retinitis Patients in Southern Thailand

Purpose: To describe the incidence of and risk factors for visual acuity (VA) loss in patients with AIDS and cytomegalovirus (CMV) retinitis.

Methods: A total of 132 patients were included. The main outcome measurements were the incidences of VA loss to ≤20/50 and ≤20/200.

Results: The incidences of VA loss to ≤20/50 and ≤20/200 were 0.22/eye-year (EY) and 0.12/EY, respectively. Risk factors for the incidence of VA loss to ≤20/50 were low nadir CD4⁺ T-cell count (adjusted hazard ratio [aHR], 3.1), large area of retinitis (aHR, 3.7), and no immune recovery (IR) (aHR, 13.9). Risk factors for the incidence of VA loss to ≤20/200 were not receiving highly active antiretroviral therapy (HAART) (aHR, 4.4) and large retinitis area (aHR, 2.1).

Conclusions: The incidence of VA loss in eyes affected by CMV retinitis was high. The use of HAART, particularly with subsequent immune recovery, substantially reduced the incidence of VA loss.     

A literature review of the use of environmental sampling in the surveillance of avian influenza viruses

This literature review provides an overview of use of environmental samples (ES) such as faeces, water, air, mud and swabs of surfaces in avian influenza (AI) surveillance programs, focussing on effectiveness, advantages and gaps in knowledge. ES have been used effectively for AI surveillance since the 1970s. Results from ES have enhanced understanding of the biology of AI viruses in wild birds and in markets, of links between human and avian influenza, provided early warning of viral incursions, allowed assessment of effectiveness of control and preventive measures, and assisted epidemiological studies in outbreaks, both avian and human. Variation exists in the methods and protocols used, and no internationally recognized guidelines exist on the use of ES and data management. Few studies have performed direct comparisons of ES versus live bird samples (LBS). Results reported so far demonstrate reliance on ES will not be sufficient to detect virus in all cases when it is present, especially when the prevalence of infection/contamination is low. Multiple sample types should be collected. In live bird markets, ES from processing/selling areas are more likely to test positive than samples from bird holding areas. When compared to LBS, ES is considered a cost‐effective, simple, rapid, flexible, convenient and acceptable way of achieving surveillance objectives. As a non‐invasive technique, it can minimize effects on animal welfare and trade in markets and reduce impacts on wild bird communities. Some limitations of environmental sampling methods have been identified, such as the loss of species‐specific or information on the source of virus, and taxonomic‐level analyses, unless additional methods are applied. Some studies employing ES have not provided detailed methods. In others, where ES and LBS are collected from the same site, positive results have not been assigned to specific sample types. These gaps should be remedied in future studies.