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Showing posts with label zoonosis. Show all posts
Showing posts with label zoonosis. Show all posts

Friday, July 20, 2018

Cows and pigs are great livestock, but they can also make you really sick

Cows and pigs are great livestock, but they can also make you really sick.Sometimes in this world, it’s the little things that can cause the most problems. Really, really little things. This is especially true for anyone working around or with livestock in Maine, according to Dr. Anne Lichtenwalner, director of the University of Maine Veterinary Diagnostic Laboratory and associate professor of animal and veterinary science. Some farm animals can actually “share” parasites with their human companions. “There are actually just a handful of parasites that I worry about,” Lichtenwalner said. “These are critters that are parasites that can live inside you and tend not to be fatal, but that can cause some ugly surprises.” The two most common zoonotic parasites — those that can transfer from animals to humans — in Maine are Ascaris suum and Cryptosporidium. “You are protected by your innate and acquired immune system,”

How animal parasites find a home in humans.

How animal parasites find a home in humans. There has been a lot of buzz recently about a video shared by Oregon woman Abby Beckley, who describes removing worms from her eye. Researchers at the Centers for Disease Control and Prevention released a case report documenting Beckley’s infection as the first human case of the cattle eyeworm Thelazia gulosa. We certainly feel for Beckley having to go through this ordeal, and without a doubt, felt our skin crawl just thinking about it. But aside from the “creep” factor of this case, it does makes us wonder how a cow parasite ever ended up in a human eye. And it begs the more fundamental question: How are animal parasites able to infect humans? To answer this question, we need to understand more about parasites and their ecology. As a veterinarian and disease ecologist, my research examines what ecological factors influence the emergence of zoonoses — diseases that spread from animals to humans. The case of the cattle eyeworms is certainly intriguing. Transmission of parasites from one host to another can occur through several routes, depending on where the parasite resides in the host and how it is shed, for example through feces, blood or other bodily secretions. Direct contact, consumption of contaminated water or food (Cryptosporidium, Giardia), or via a vector like a tick or mosquito are all possible. Parasitic infections transmitted from animals to humans have occurred naturally throughout history.

Bacteria carried by unneutered dogs could put pregnant women at risk.

Bacteria carried by unneutered dogs could put pregnant women at risk. Intact dogs can carry Brucella canis bacteria, which can cause flu-like symptoms in people and pose risk to a pregnancy, according to a study in Emerging Infectious Diseases. Brucellosis infections can cause miscarriages in animals and are associated with fetal problems in pregnant women, and the CDC says pregnant women who may have been exposed to the bacteria should consult their health care provider. A bacteria carried by dogs that haven't been neutered can produce flu symptoms in humans and potentially jeopardize a pregnancy, a new study suggests. Brucellosis infection is most commonly spread by livestock like sheep, cattle, goats and pigs. But a strain of the bacterium carried by dogs -- Brucella canis -- could be widespread in humans, warned lead researcher Martha Hensel, a veterinarian with Texas A&M University. B. canis is carried by dogs that can still reproduce, Hensel noted. It's not clear exactly how the bacteria might spread to humans, but it's most likely passed through contact with reproductive organs or urine. People who regularly handle such dogs -- vets, dog shelter employees, dog breeders -- are most at risk for contracting brucellosis, Hensel said. However, pet ownership is a likely risk factor for infection, particularly for young children and people with compromised immune systems, Hensel and her colleagues explained. The researchers highlighted some case studies: 1) A 3-year-old New York City girl came down with brucellosis in 2012 after exposure to an infected puppy recently purchased from a pet store. 2)Several people with HIV have developed brucellosis in recent years, all linked to intact dogs they owned that were later diagnosed with B. canis infection. more

Monday, July 9, 2018

Transmission of NDM bacteria between dogs and humans established.

Transmission of NDM bacteria between dogs and humans established.The transmission of NDM bacteria between dogs and humans has been established for the first time. In 2015, a New Delhi-metallo-beta-lactamase (NDM) Escherichia coli bacteria was discovered in two Finnish dogs. An article recently published in the journal Eurosurveillance reveals that the dogs' owner did also carry the bacterium. This is presumably the first time in the world that the transmission of NDM-bacteria between a dog and a human has been reported. The NDM-bacteria that had originally been isolated from ear specimens from two dogs in the same family initiated an investigation about the spread and origin of the bacteria. Specimens were also taken from family members and the dogs. The relatedness of the bacteria were investigated by examining the nucleotide sequence of their genome. The study was a collaboration between the University of Helsinki, the National Institute of Health and Welfare, and the Finnish Food Safety Authority Evira.

Friday, July 6, 2018

Dogs can be a potential risk for future influenza pandemic.

Dogs can be a potential risk for future influenza pandemic.Dogs are a potential reservoir for a future influenza pandemic, according to a study published in the journal mBio. The study demonstrated that influenza virus can jump from pigs into canines and that influenza is becoming increasingly diverse in canines. Influenza can jump among animal reservoirs where many different strains are located; these reservoirs serve as mixing bowls for the genetic diversity of strains. Pandemic influenza occurs when viruses jump from animal reservoirs to humans; with no prior exposure to the virus, most people do not have immunity to these viruses. The main animal hosts for influenza are wild birds, poultry and other domestic birds in a species pack; swine; and horses. Some of the viral genes from the 2009 pandemic H1N1 virus originated in birds, from an avian virus that jumped to pigs, exchanged some of its genes with previously circulating swine viruses and then jumped from pigs into humans. Birds and swine are major reservoirs of viral genetic diversity, whereas equines and canines have historically been restricted to one or two stable influenza A viruses lineages with no or very limited transmission to humans.

Saturday, December 9, 2017

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.

Four in hospital isolation after contracting anthrax.

Four in hospital isolation after contracting anthrax. Four people have been put in an isolation ward at Mt Kenya Hospital Nyeri after been suspected to be infected with anthrax. Nyeri Central sub-county commissioner John Marete said the two brothers and their two neighbours from Thunguma village are reported to have eaten uninspected meat in Ruiru, Kiambu County before travelling to Nyeri on Friday. Mr Marete confirmed that the patients presented themselves at Nyeri Referral Hospital on Saturday morning and were immediately transferred to the health facility after screening. “They went to the county hospital in the morning and were immediately transferred to Mt Kenya hospital. They are receiving treatment at an isolation room since Anthrax is a contagious disease,” said Mr Marete.

Thursday, December 7, 2017

A new way to treat parasitic infections discovered.

A new way to treat parasitic infections discovered. UT Southwestern Medical Center researchers have identified a chemical that suppresses the lethal form of a parasitic infection caused by roundworms that affects up to 100 million people and usually causes only mild symptoms. The Centers for Disease Control and Prevention (CDC) reports that the soil-dwelling Strongyloides stercoralis nematode, or roundworm, is the primary strongyloides species that infects humans. Experts estimate that between 30 million and 100 million people are infected worldwide, and most of them are unaware of it because their symptoms are so mild. The parasite can persist for decades in the body because of the nematode's unique ability to reinfect the host, repeatedly going through the early stages of its life cycle. The nematode that causes the original infection exists in dirt on all continents except Antarctica, and it is most common in warmer regions, particularly remote rural areas in the tropics and subtropics where walking barefoot combined with poor sanitation leads to infection. However, in people with compromised immune systems -- such as those using long-term steroids for asthma, joint pain, or after an organ transplant -- the mild form of the illness can progress to the potentially lethal form, a situation called hyperinfection. Studies indicate that mortality from untreated hyperinfection can be as high as 87 percent. The World Health Organization reports that although the parasitic illness has almost disappeared in countries where sanitation has improved, children remain especially vulnerable in endemic regions due to their elevated contact with dirt. Further, the drug of choice, ivermectin, is unavailable in some affected countries.

Monday, December 4, 2017

Reverse zoonosis. How human pathogens affect animals.

Reverse zoonosis. The fact that diseases can pass from humans to animals is, perhaps, not such a surprise. An estimated 61.6 percent of human pathogens are regarded as multiple species pathogens and are able to infect a range of animals. Also, over 77 percent of pathogens that infect livestock are multiple species pathogens. One of the earliest studies demonstrating reverse zoonosis was conducted in 1988 and looked at dermatophytes - fungi that cause superficial infections of the skin, nails, and hair - including Microsporum and Trichophyton. The authors found that these fungi could be transmitted from animal to animal, human to human, animal to human, and human to animal. From 2000, studies began to emerge investigating the ability of certain parasites to pass from human to animal, including Giardia duodenalis (the parasite responsible of giardiasis), and Cryptosporidium parvum (a microscopic parasite that causes the diarrheal disease cryptosporidiosis).Reverse zoonosis. A study, published in the journal Veterinary Microbiology in 2006, looked at methicillin-resistant Staphylococcus aureus (MRSA) in pets and its transmission between humans and animals.The paper mentions a specific case in which a couple was repeatedly infected with MRSA. The re-infections only stopped once their dog was identified as the source and treated. It is presumed that the dog was initially infected by the couple and then passed the infection back to them each time they had been successfully treated. The emergence of MRSA in household pets is of concern in terms of animal health and the potential for animals to act as sources of infection or colonization of human contacts.Reverse zoonosis. A paper, published in 2004, describes the case of a 3-year-old Yorkshire terrier who arrived at the University of Tennessee College of Veterinary Medicine with anorexia, vomiting, and a persistent cough. After running a barrage of tests - including, sadly, an eventual postmortem - the authors concluded that it had contracted tuberculosis (TB) (Mycobacterium tuberculosis). The dog's owner had been receiving treatment for TB for 6 months. This was the first documented transmission of TB from human to canine. In 2009, the first recorded case of fatal human-to-cat transmission of the H1N1 flu virus occurred in Oregon. The owner of the cat had a severe case of influenza and had to be taken to the hospital. Her cat - an indoor cat with no exposure to other people or animals - later died of pneumonia caused by an H1N1 infection. Details of the case were published in the journal Veterinary Pathology. In 2011 and 2012, researchers identified more than 13 cats and one dog with pandemic H1N1 infection that appeared to have come from human contact. Interestingly, the animals' symptoms were similar to those experienced by human carriers - rapidly developing respiratory disease, a lack of appetite and, in some cases, death.

Re-emerging zoonosis: Fascioliasis.

Re-emerging zoonosis are zoonotic infections that have been recognized before and has protocol measures of prevention and treatment in place,but now these infections have higher incidences and wider geographic scope. Fascioliasis is one of such re-emerging zoonotic infections that was common in developing nations of Africa and sparse dispersion in America,Europe and Asia. Today this infection is widespread and with higher prevalence. The food-borne trematodes causing infection in man are Fasciola hepatica and gigantica are the 2 most common in the tropics. Transmission is by ingestion of flukes in under-cooked or poorly processed liver. Drinking water contaminated with the flukes and eating water plants or vegetables washed with such water. Accidental ingestion of flukes from infected liver as shown below is very common in developing countries. Butchers usually cut up affected liver in strips to cut out the white tracts formed by the flukes. This is usually called Eedo oni ishan, they typically sell to food vendors and people who want meat that you chew for long before swallowing. The next time you visit your butcher and observe livers cut up with tracts,donot buy.
Acute phase. when the immature worms penetrate the intestinal wall and the peritoneum, the protective membrane surrounding the internal organs .They puncture the liver's surface and eat their way through its tissues until they reach the bile ducts. This invasion kills the liver cells and causes intense internal bleeding. Typical symptoms include fever, nausea, a swollen liver, skin rashes and extreme abdominal pain and inflammation. Chronic phase. The chronic phase begins when the worms reach the bile ducts, where they mature and start producing eggs. These eggs are released into the bile and reach the intestine, where they are evacuated in faeces, thereby completing the transmission cycle. Symptoms include intermittent pain, jaundice and anaemia. Pancreatitis and gallstones. Patients with chronic infections experience hardening of the liver (fibrosis) as a result of the long-term. The fluke sometimes migrates from the liver to the eye and nervous tissue. The migration causes neurological signs such as tremors/seizures .Ocular lesions arise from migration to the eyes, where there is occasional moving out of fluke from orbit.

Tuesday, February 16, 2016

First confirmed human infection of zoonotic parasite reported in Vietnam.

Researchers have reported the first laboratory-confirmed case of Trypanosoma evansi infection in a Vietnamese woman with no deficiencies. They linked transmission of the parasite with bovid exposure. Over half of Vietnam’s population resides in rural areas, and most participate in small-scale animal production, which likely facilitates the transfer of pathogens from animals into humans,” the researchers wrote. “T. evansi is associated with acute disease in camels and horses and chronic disease in cattle and buffalo, and can be found in South America, North Africa, the Middle East, South and Southeast Asia.” There have been four probable cases of T. evansi infection reported worldwide that lacked molecular parasite speciation. One previous case was reported in India in 2005 with molecular confirmation, although the patient had a deficiency of Apolipoprotein L1 (APOL1), a serum component with trypanocidal activity. The present case, a previously healthy Vietnamese woman aged 38 years with no APOL1 deficiency, first presented to a health care facility with 18 days of fever, headache and arthralgia. She had no history of travel to any regions where T. evansi has been observed. Although initially treated for malaria, microscopic examination of blood samples revealed unicellular flagellate protozoa with the morphology of Trypanosoma. The patient received a treatment reported to have trypanocidal activity for 7 days, but returned with symptoms 6 weeks after discharge and subsequently treated with a first-line anti-trypanosomal treatment and eventually recovered with no complications. PCR amplification and serological testing of the patient’s serum confirmed the infecting species as T. evansi, and APOL1 testing found the patient’s concentrations to be within a healthy range. As the patient reported potential exposure while butchering locally reared beef, the researchers conducted a census of livestock farms surrounding the patient’s relatives’ household. Blood samples from some cattle and buffalo were indicative of T. evansi infection, and some farmers reported a mystery illness affecting their livestock. These data helped the researchers conclude that these bovid were the likely source of the patient’s infection. Furthermore, the parasite may have been circulating among Vietnamese livestock for some time while avoiding detection, and if endemic could have further economic and human health consequences for the region. “Subsequent field investigations demonstrated a high prevalence of bovids in the immediate environs of the patient with clinical and molecular evidence of T. evansi infection,” the researchers wrote. “Further research is required to better understand this zoonotic pathogen, including host susceptibility factors, potential vectors and therapeutic options for both human and animal infections.” – story source; Helio infectious news.oo