Campylobacter in poultry.

Campylobacter in poultry. Campylobacter is a leading cause of foodborne gastroenteritis in humans worldwide. Campylobacter is, in general, highly prevalent on poultry farms, but the prevalence varies by region, seasons and production types, with reported Campylobacter-positive flocks ranging from 2% to 100%. Once a broiler flock is infected with Campylobacter, the majority of birds become colonized within a few days, and the overall within-flock prevalence reaches very high levels by processing age, leading to increased carcass contamination. Campylobacter is ubiquitous in the poultry farm environment, and the sources of flock infection and risk factors influencing Campylobacter introduction are complex but horizontal transmission from environmental sources is the primary way flocks become colonized. Some of the most common factors associated with Campylobacter colonization in commercial broilers are poor farm biosecurity; the presence of other animals in the vicinity of poultry houses such as other poultry species, livestock, pets and wildlife; older processing age; large flock size; the use of ventilators; the presence of flies and rodents; and the use of old litter. Campylobacter can be introduced onto poultry farms by farm equipment, transport vehicles and farm workers. The prevalence of colonization tends to be much higher during hot weather. Campylobacter is common in the farm environment and can contaminate poultry houses via many different routes, preventing flock colonization with this organism is not an easy task, but these measures could help. Biosecurity and hygiene: Implementing strict biosecurity and good hygiene measures can help prevent Campylobacter from entering the broiler house from the outside environment. Treatment of drinking water: Acidification of drinking water with organic acids such as lactic acid, acetic acid or formic acid and water chlorination, especially when combined with other approaches, may decrease the risk of Campylobacter colonization in broilers. Litter treatment: Acidification of litter with aluminum sulfate and sodium bisulfate may decrease Campylobacter colonization frequency and cecal loads. Litter treatment with a combination of sodium bisulfate, ammonium sulfate and magnesium sulfate can significantly reduce the pH and moisture of litter as well as the numbers of contaminating Campylobacter, subsequently reducing colonization of chickens. Feed additives: A combination of 2% formic acid and 0.1% potassium sorbate in feed has been shown to be effective for preventing the colonization of broilers.

Campylobacter in poultry: An elusive pathogen.

Campylobacter in poultry: An elusive pathogen. Campylobacter — primarily Campylobacter jejuni and Campylobacter coli — frequently colonize the intestinal tract of domestic poultry at high levels. The bacterium is well adapted to the avian host and, despite extensive colonization, it produces little or no overt disease in poultry. That makes it difficult to detect and control in live birds. Despite its insignificance for poultry health, Campylobacter is a leading cause of foodborne gastroenteritis in humans worldwide.The poultry reservoir, especially broiler meat, is the most commonly recognized source for human Campylobacter. Campylobacter is, in general, highly prevalent on poultry farms, but the prevalence varies by region, seasons and production types, with reported Campylobacter-positive flocks ranging from 2% to 100%. Once a broiler flock is infected with Campylobacter, the majority of birds become colonized within a few days, and the overall within-flock prevalence reaches very high levels by processing age, leading to increased carcass contamination. A unique feature of Campylobacter ecology in poultry is that birds younger than 2 to 3 weeks of age are almost never colonized by the organism in commercial production settings, which implies that young birds have a biological mechanism for colonization resistance. If the reasons for this colonization resistance are revealed, they could be used to design effective strategies to prevent birds from getting infected.

Avian flu: Virus with an Eggshell.

Avian flu: Virus with an Eggshell. Avian flu can be transmitted from birds to humans; transmission among humans, however, is limited. The reason may be an eggshell-like mineral layer that the virus acquires due to the high calcium concentration in the intestines of birds. As reported by Chinese researchers in the journal Angewandte Chemie, these mineralized viruses are significantly more infectious and, in addition, more robust and heat stable than the native viruses. Avian flu is a highly infectious disease among birds that has developed into a serious threat to human health. Close contact with diseased birds or their feces is considered to be the primary source of infections in humans. Transmission between humans is limited, however, which indicates that these viruses cannot directly infect humans. Previously it was assumed that these viruses crossed the species barrier as a result of mutation or recombination with another pathogen. More recent results demonstrate that avian flu viruses isolated from infected humans have the same gene sequences as those from birds.Avian flu: Virus with an Eggshell. So how is it that humans catch the disease from birds? Researchers working with Ruikang Tang at Zhejiang University (Hangzhou, China) claim that it is because the viruses acquire a mineral "shell" in the bird intestines. They discovered that viruses can become mineralized under calcium-rich conditions. Naturally, the digestive tract of birds--the primary location of avian flu viruses--provides just such a calcium-rich environment, so that the birds can make egg shells.Avian flu: Virus with an Eggshell. Experiments with a solution that imitates the bird intestine environment allowed the researchers to demonstrate that 5 to 6 nm shells of a calcium phosphate mineral form around H9N2 and H1N1 viruses. In both cell cultures and mice, these mineralized viruses proved to be significantly more infectious--and deadly--than the native viruses. In humans, avian flu viruses infect the airways and are then found in bodily fluids, where the calcium concentration is too low for mineralization.

Breeding Resistant Chickens for Improved Food Safety.

Breeding Resistant Chickens for Improved Food Safety. A recent test developed by Agricultural Research Service (ARS) scientists in College Station, Texas, could make it easier to breed pathogen-resistant chickens. The test identifies roosters whose blood contains naturally high levels of two key chemicals, cytokines and chemokines. These chemicals mobilize the birds' innate immune response, according to ARS microbiologist Christi Swaggerty, in ARS's Food and Feed Safety Research Unit. Using the new test, commercial poultry breeders can single out roosters that have a strong immune response and use them to selectively breed a more robust flock. Such resistance, especially during the birds' first week of life, may lower costs related to animal well-being and food safety. Protecting chickens from pathogens involves sanitation, vaccination, biosecurity and use of antibiotics and other medications. But some chickens have an especially robust and efficient immune response and can resist pathogens, notes Swaggerty.

TB a leading cause of death among children worldwide.

TB a leading cause of death among children worldwide. Tuberculosis ranks among the top 10 causes of death among children around the world, a mathematical modeling study showed. Researchers wrote that the disease represents a “key omission” from analyses of mortality in children aged younger than 5 years. “The UN Inter-agency Group on Child Mortality Estimation tracks overall under-5 mortality, and breakdowns by cause of death have been estimated by the study group formerly known as the Child Health Epidemiology Reference Group, most recently in 2016,” Peter J. Dodd, PhD, of the University of Sheffield, UK, and colleagues wrote. “These estimates have been important in assessing progress toward targets, directing public health funding and spending and for advocacy. However, tuberculosis has never been explicitly mentioned in these reports. The researchers used a mathematical model to estimate deaths of children aged younger than 5 years in 217 countries and territories. Dodd and colleagues disaggregated WHO pediatric TB estimates by age, as well as treatment status and HIV status, using pediatric TB notification data and pediatric ART estimates. Most deaths –more than 70% – occurred in southeast Asia and Africa (n = 182,000; 95% CI, 140,000-239,000), the researchers reported. Seventeen percent (n = 39,000; 95% CI, 23,000-73,000) of children who died had HIV, with 31,000 of those children living in Africa (36%; 95% CI, 19,000-59,000). The vast majority of children who died (96%; n = 230,000; 95% CI, 185,000-289,000) did not receive treatment for TB, Dodd and colleagues wrote. The large mortality burden of undiagnosed pediatric tuberculosis should … not spur hopelessness, but action; these new estimates identify a prime opportunity to address an under-recognized and preventable cause of child deaths.

Surge in human H7N9 cases caused by poultry, not people.

Surge in human H7N9 cases caused by poultry, not people. New study findings indicate that the recent surge in human influenza A(H7N9) cases in China is probably due to increased spread from poultry to people and not because of a swell in human-to-human transmission. With a case fatality rate of around 40%, experts consider H7N9 to be one of the most troubling infectious disease threats in the world because of its potential to cause a deadly pandemic. So far, most of the more than 1,500 human cases since 2013 have been transmitted from poultry, not people. Since 2013, China has been struck by five epidemics of H7N9, the most recent one being by far the largest and most widespread. In addition to a record number of human cases, the fifth epidemic produced evidence that the virus had split into two strains, including one that was no longer susceptible to the old vaccine and was becoming harder to treat. The CDC developed a new vaccine, replacing the old one that was based on viruses taken after H7N9 emerged in 2013.

Many health care workers do not know correct influenza precautions.

Many health care workers do not know correct influenza precautions. In a small survey conducted at a St. Louis hospital, many health care personnel could not describe the correct transmission-based precautions for patients with influenza, and some even said they had reservations about the safety and effectiveness of the influenza vaccine. Hilary M. Babcock, MD, MPH, associate professor of medicine in the division of infectious diseases at Washington University School of Medicine, and colleagues surveyed 170 full- and part-time health care personnel (HCP) at a long-term care (LTC) facility with a mandatory influenza vaccination policy. Just 73 people responded to the survey. Among those, 42 reported closer contact with patients — including many nurses — and 21 said they had less patient contact working in jobs such as food service worker and administrator. Skip to main content