Tag Archives: zoonotic diseases

Domestic Livestock and Public Health / Animales Domésticos Y Salud Pública

Small-scale livestock production plays an essential role as a source of income and nutrition for households in low-and middle-income countries, yet these practices can also increase risk of zoonotic infectious diseases, especially among young children.

The study upon which the video is based is: Detection of zoonotic enteropathogens in children and domestic animals in a semi-rural community in Ecuador. Appl & Env Microbiol, May 2016. Authors: Karla Vasco, Jay P. Graham and Gabriel Trueba.

Emerging Issues of Environmental Concern: UNEP Frontiers 2016 Report

Emerging Issues of Environmental Concern: UNEP Frontiers 2016 Report, 2016. UNEP.

The UNEP Frontiers 2016 edition presents six emerging issues. It highlights, for example, that the global significance of the financial sector should not confine itself only to enhancing global economic growth, but also to advancing environmental sustainability. The financial sector has a crucial role to play in investing in new low-carbon, resource efficient and environmentally sound assets, and shifting capital away from traditional assets that have high impacts on the environment. The report presents a number of emerging financial initiatives led by the financial sector as innovative solutions to sustainability challenges.

There is a worldwide increase in disease emergence and epidemics particularly from zoonoses – diseases that can be passed on between animals and humans. The report illustrates how the emergence and re-emergence of zoonotic diseases are closely interlinked with the health of ecosystems. The risk of disease emergence and amplification increases with the intensification of human activities surrounding and encroaching into natural habitats, enabling pathogens in wildlife reservoirs to spill over to livestock and humans.

The recent years have seen a growing presence of plastic pollution in the aquatic environment, particularly in form of microplastics. While stakeholders are increasing their efforts to reduce the use of microplastics through innovative approaches and policy change, the scientific community is racing to understand the level of exposure and physiological impacts of microplastic contaminants on various organisms, as well as the risk to human health through consumption of contaminated food.

The UNEP Frontiers report also highlights two critical issues associated with climate change. The issue of loss and damage to ecosystems due to changing climate has risen to global attention in recent years, and has led to the establishment of the Warsaw international mechanism for loss and damage associated with climate change impacts. The report introduces a number of case studies on recent sudden- and slow-onset events that have caused losses and damages to ecosystems and human systems, and presents a range of risk management tools needed to avoid harm.

 

 

Human fecal and pathogen exposure pathways in rural Indian villages and the effect of increased latrine coverage

Human fecal and pathogen exposure pathways in rural Indian villages and the effect of increased latrine coverageWater Research, Volume 100, 1 September 2016, Pages 232–244.

Authors: Mitsunori Odagiri, Alexander Schriewer, et al.

Highlights

  • Application of Bacteroidales MST to evaluate improved sanitation impacts
  • Widespread human and animal fecal contamination detected in homes.
  • Pathogens detected in drinking sources associated with subsequent child diarrhea.
  • Public ponds used domestically were heavily contaminated with multiple pathogens.
  • No decrease in human fecal or pathogen contamination from increased latrine coverage.

In conclusion, the study demonstrates that

  • (1) improved sanitation alone may be insufficient and further interventions needed in the domestic domain to reduce widespread human and animal fecal contamination observed in homes,
  • (2) pathogens detected in tubewells indicate these sources are microbiologically unsafe for drinking and were associated with child diarrhea,
  • (3) domestic use of ponds heavily contaminated with multiple pathogens presents an under-recognized health risk, and
  • (4) a 27 percentage point increase in improved sanitation access at village-level did not reduce detectable human fecal and pathogen contamination in this setting.

 

Endemicity of Zoonotic Diseases in Pigs and Humans in Lowland and Upland Lao PDR: Identification of Socio-cultural Risk Factors

Endemicity of Zoonotic Diseases in Pigs and Humans in Lowland and Upland Lao PDR: Identification of Socio-cultural Risk Factors. PLoS Neg Trop Dis, April 2016. Authors: Hannah R. Holt , Phouth Inthavong, et al.

In Lao PDR, pigs are an important source of food and income and are kept by many rural residents. This study investigated five diseases that are transmitted between pigs and humans (zoonoses), namely hepatitis E, Japanese encephalitis, trichinellosis, cysticercosis and taeniasis. Humans and pigs in Lao PDR were tested for antibodies against the agents (pathogens) responsible for these diseases. Human participants were classified into three groups or “clusters” based on hygiene and sanitation practices, pig contact and pork consumption.

Cluster 1 had low pig contact and good hygiene practice. Cluster 2 had moderate hygiene practices: around half used toilets and protected water sources; most people washed their hands after using the toilet and boiled water prior to consumption. Most people in this cluster were involved in pig slaughtering, drank pigs’ blood and were more likely test positive for antibodies against hepatitis E and Japanese encephalitis viruses. Finally, people in cluster 3 had lowest access to sanitation facilities, were most likely to have pigs in the household and had the highest risk of hepatitis E, taeniasis and cysticercosis.

The diseases in this study pose a significant threat to public health and impact pig production. This study identified characteristics of high-risk individuals and areas with high disease burden and could be used to target future disease control activities to those most vulnerable.

 

Ruminants contribute fecal contamination to the urban household environment in Dhaka, Bangladesh

Ruminants contribute fecal contamination to the urban household environment in Dhaka, Bangladesh. Env Sci Tech, April 2016. Authors: Angela Harris, Amy Janel Pickering, et al.

In Dhaka, Bangladesh, the sensitivity and specificity of three human, three ruminant, and one avian source-associated QPCR microbial source tracking assays were evaluated using fecal samples collected on site. Ruminant-associated assays performed well, while the avian and human assays exhibited unacceptable cross-reactions with feces from other hosts.

Subsequently, child hand rinses (n=44) and floor sponge samples (n=44) from low income-households in Dhaka were assayed for fecal indicator bacteria (enterococci, Bacteroidales, and Escherichia coli) and a ruminant-associated bacterial target (BacR). Mean enterococci concentrations were of 100 most probable number (MPN)/2 hands and 1000 MPN/225 cm2 floor. Mean concentrations of Bacteroidales were 106 copies/2 hands and 105 copies/225 cm2 floor. E. coli were detected in a quarter of hand rinse and floor samples. BacR was detected in 18% of hand rinse and 27% of floor samples.

Results suggest that effective household fecal management should account not only for human sources of contamination but also for animal sources. The poor performance of the human-associated assays in the study area calls into the question the feasibility of developing a human-associated marker in urban slum environments, where domestic animals are exposed to human feces that have been disposed in pits and open drains.