Viruses that cause avian influenza are capable of replicating at temperatures higher than a typical fever, according to a study in in vitro models and mice. ‘Fever-resistant replication could help explain why avian viruses and pandemic influenza viruses with avian PB1 cause more severe disease in humans,’ the authors write in the journal Science.
US Department of Health Secretary Robert Kennedy Jr's proposal to let bird flu spread in turkeys and chickens to identify surviving animals would be "dangerous and unethical", a group of scientists warns in a policy forum article published by Science. In addition to the suffering of infected animals, allowing a highly lethal, rapidly evolving and contagious virus to follow a natural course of infection "would prolong exposure for farmworkers, which could increase viral adaptation and transmission risks for poultry, other peridomestic animals, and humans," they warn.
A team in the US has tested the efficacy of baloxavir, an antiviral already on the market for treating common flu, against avian influenza in mice. The results, published in the journal Nature Microbiology, show that it is more effective than the currently recommended oseltamivir (Tamiflu) except when the infection is via the mouth, in which case it is equally effective. According to the authors, baloxavir ‘could be considered for the potential treatment of serious H5N1 virus infections in humans’.
A team of researchers from the USA has analyzed the B lymphocytes of seven healthy people in whom no exposure to H5 influenza viruses, such as the avian flu virus, had been documented. The results show that they present antibodies capable of recognizing this type of virus, which, according to the authors, could represent “a first line of defense” in the event of a pandemic. The results are published in the journal Science Immunology.
A review published in Science estimates that 2 % of rodent species are hyper-reservoirs, hosting and transmitting more than three pathogens to humans, including Lyme disease, Lassa fever and plague. In addition, the authors estimate that 10 % of rodents are reservoirs for one to three pathogens. These are especially so-called synanthropic species - animals that live close to humans and are able to adapt to these environments - such as black rats, Norway rats and house mice.
A study carried out in China has analyzed tissues from 461 fur animals, mostly farm-raised. They found 125 virus species, 39 of which presented a high risk of interspecies transmission. According to the authors, who publish the results in the journal Nature, “there is a need for more extensive and regular surveillance to assess the public health risks that could result from fur animal farming”.
The H5N1 avian influenza virus can be transmitted between mammals, according to a study published in Nature. The research team isolated the virus from the milk of an infected cow in New Mexico (USA) and found that it spreads in mice and ferrets, reaching the mammary glands of both animals. In addition, the virus was also transmitted from infected lactating mice to their offspring. The European Centre for Disease Prevention and Control (ECDC) has issued a press release on Monday recommending increased surveillance for these viruses.
The World Health Organisation (WHO) has announced that a 59-year-old man infected with the H5N2 avian influenza virus died in Mexico on 24 April. This is the first confirmed human infection with the virus. The patient had multiple underlying medical conditions and had been bedridden for three weeks for other reasons before showing symptoms. The source of infection is unknown. The WHO assesses the risk to the general population as low.
The European Centre for Disease Prevention and Control (ECDC) reported that on January 29th, Spanish authorities notified a possible case of human infection with swine flu virus A(H1N1)v in a worker from a Catalan pig farm. After being diagnosed with bronchitis, subsequent laboratory analyses confirmed it as swine flu A(H1N1)v. The ECDC informs that the patient has fully recovered, and to date, no new cases have been detected among close contacts or among the worker's colleagues at the farm.
A review examines the role of domestic and semi-domestic animals, such as cats, in the emergence of potential zoonoses due to their close contact with humans. The paper, published in the journal Science Translational Medicine, concludes that companion animal health risks will become increasingly problematic with climate change and rapid urbanisation.