Sunday, December 10, 2017
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.
Friday, April 8, 2016
Researchers have found antibodies to the newly discovered influenza D virus in pigs, cattle, horses, goats and sheep, but not poultry. A researcher has proven that the guinea pig can be used as an animal model and is developing a way to study the virus in living cells—trachea and lung epithelial cells from swine and cattle. To identify exposure to the virus, South Dakota State University doctoral student Chithra Sreenivasan tests blood samples for influenza D antibodies. Working with the Minnesota Poultry Testing Lab, she found no evidence of the new influenza strain in poultry; however, she did find antibodies to the virus in sheep and goats from the Midwest through blood samples archived at Washington State University. The virus has not been shown to be pathogenic in humans, the goal is to determine whether the virus can cause problems in humans.If the virus can undergo reassortment in combination with a closely related human influenza virus, it may be able to form a new strain that could pose more of a threat to humans. Using the bovine Influenza D strain, Sreenivasan proved that the guinea pig could be used as an animal model to study the virus. Though guinea pigs showed no symptoms, she successfully isolated antigens in tracheal and lung tissues. In addition, her research showed the virus is spread only through direct contact. Those results were published in the Journal of Virology, with Sreenivasan as the first author of the article. Influenza D has about 50 percent similarity to human influenza C. Human C affects mostly children, the most common symptom is a runny nose. It's not a serious disease as we all have some antibodies because we were infected as children. source; science daily.
Wednesday, March 16, 2016
Porcine Epidemic Diarrhoea virus (PEDv) is devastating in herds especially in Asia and North America although the recent outbreaks of PEDv-like strains in Europe appear less destructive. Porcine Epidemic Diarrhoea (PED) is an economically important enteric disease in pigs caused by a Corona virus. Corona viruses can be divided into the genera Alpha corona virus, Beta corona virus, Gammacoronavirus and Deltacoronavirus. The Alpha corona viruses including Transmissible Gastroenteritis virus (TGEv), Porcine Respiratory Coronavirus (PRCv) and Porcine Epidemic Diarrhoea virus (PEDv) are the most important in swine. While TGEv and PRCv belong to the Alpha corona virus 1 species, PEDv belongs to a separate species within the same genus. The Beta corona viruses induce severe diseases in humans like Severe Acute Respiratory Syndrome (SARS-Cov) or Middle East Respiratory Syndrome (MERS-Cov), the Beta corona virus affecting pigs called Hemagglutinating Encephalomyelitis virus (HEv) is of minor importance for the swine industry. The Delta corona virus infections (porcine Delta corona virus, PDCov) were reported in pigs in Asia and North America which caused enteric diseases similar to PEDv but of lower clinical impact and disease severity. PED first appeared as acute diarrhoea in finishing pigs in the early 1970s in the UK and subsequently spread fast across Europe causing acute outbreaks of diarrhoea in pigs of all age groups. The routes of PEDv transmission between different areas, countries and even continents remain poorly understood. The origin of recently identified PEDv strains in Europe showing high nucleotide similarity to US S-INDEL PEDv strains remains unclear. It is not known if those strains have been circulating in the European pig population for a long time or if they were recently introduced into Europe. The various methods to applied so far to control PED virus on farms, include the following 1) Increasing sow immunity can be achieved by giving feedback. This usually involves feeding intestines or diarrheic faces from acutely infected piglets to sows to convey immunity. Different protocols are followed; no additives should be added. 2) Weaning down is also a much applied strategy – this means weaning at about ten days of age. 3)Improving biosecurity. 4)Applying strict disinfection, e.g. using Synergize, Virkon S. 5)Vaccinating. There are two inactivated vaccines available. The best success is usually achieved in pre-infected herds.
Wednesday, February 17, 2016
Scientists/researchers have warned tourist/holiday enthusiast to stay away from animals including bats on such travelling.This advice came on the heels of a lady that died after she was bitten by a dog while on a trip in India for 2 weeks. Rabies is an acute viral infection of the central nervous system. The virus is usually transmitted through a dog bite, and results in at least 40,000 deaths worldwide every year.Around 90% of deaths occur in the developing world,particularly in India, where dogs that roam freely are largely responsible. Rabies is rare in the UK, where just 12 cases have been reported since 1977, 11 contracted abroad and one rare case acquired from a bat in the UK. A team of researchers describe the case of a woman in her late 30s who was admitted to hospital with shooting pain in her lower back and left leg. Three and a half months earlier, she had been bitten by a puppy on a lead during a two week holiday in Goa. It left a slight graze, but she did not seek medical help, and she had not received a vaccination before travelling. She was diagnosed with rabies and died after 18 days in hospital. This case serves as an important reminder of the risk of rabies for any traveler to a country where rabies is endemic, even tourists on a short visit to a holiday resort, say the authors. Travelers need to know whether they are visiting a country where rabies is endemic, and that any dog bite must be taken seriously,even an apparently innocuous bite from a pet. The risk can also be reduced by avoiding contact with animals that might be susceptible to rabies. stay away from roaming dogs ,cats or wildlife.
Wednesday, January 20, 2016
Rats are carriers of both the spirochete bacteria responsible for Leptospirosis in man and animals and also the Lassa fever virus which affects man. The rat spread both infection by contamination with urine, when rats urine contaminate food and water, they spread these diseases. The consumption of rats have also been fingered in the spread of Lassa fever. The signs of Lassa infection occurs 1-3 weeks after exposure to the virus. The signs could be mild or severe and these are 1) slight fever 2) general malaise 3) weakness 4) headache. The severe signs include 1) bleeding/hemorrhaging in gums, eyes and nose. 2) respiratory distress 3)repeated vomiting 4) facial swelling 5) pain in chest ,back, abdomen and neck. Lassa fever infection also show neurological signs such as tremors, encephalitis and deafness. The treatment is supportive therapy of fluids and vitamins and Ribavirin, an antiviral drug. The prognosis is hinged on early treatment. Death usually occurs within 2 weeks after onset of symptoms. The major form of prevention is pest control; ensure your house, farms and factories are rodent proof. The proper disposal of waste is advised, remove all unfinished food and store food material on rodent-proof containers. Regular de-ratization in premises is advised. Do not eat rats. Stay safe # kill rats don’t eat them