Novel anthrax type causes wildlife deaths
A research letter in Nature yesterday said that up to 40% of all animal deaths in the Ivory Coast's Tai National Park were caused by an unusual strain of the bacteria that causes anthrax. The strain, Bacillus cereus biovar anthracis, could even lead to extinction of the park's chimpanzee population, researchers said.
The letter expands the knowledge of how anthrax spores infect wild animals in tropical ecosystems. Though anthrax is known to kill wildlife in arid environments, it wasn't until 2001 that researchers monitoring the Tai National Park discovered that chimpanzees were dying from anthrax infection. In fact, 31 of the 55 chimpanzee carcasses collected from the park in the last 26 years died from the disease.
"We predict that this pathogen will accelerate the decline and possibly result in the extirpation of local chimpanzee (Pan troglodytes verus) populations," the authors concluded.
The researchers tested 75 carcasses collected from the park over the course of 3 decades and 204 fresh carcasses. They found anthrax was behind about 40% of all mammal deaths in the park. To date, this strain of anthrax bacterium has not infected humans, but the authors predict it would do so in a similar manner to Bacillus anthracis, the typical anthrax bacterium.
Aug 2 Nature letter
New botulism toxin discovered, could be therapeutic
According to a study published today in Nature Communications, scientists have identified a novel botulinum neurotoxin that could be therapeutic. This is the first new botulism serotype discovered since 1969.
The new strain of botulism, called BoNT/X, was first identified in a Japanese infant in 1996. The gene of BoNT/X was encoded on the chromosome of Clostridium botulinum strain 111, but researchers do not yet know if BoNT/X can be expressed or exhibit toxicity.
"BoNT/X may have the potential to modulate inflammatory secretion in immune cells," the authors wrote. Researchers are now working to understand the structure of the toxin and how it binds to nerve cells.
Though botulism is one of the deadliest toxins on earth, it's also used to treat more than 80 medical conditions, from migraine headaches to overactive bladder. When injected, the toxin temporarily paralyzes muscles.
Aug 3 Nat Commun study
Studies: Rotavirus vaccine tied to sharp drops in illness in children
Two new studies from the United States and Swaziland showed significant drops in rotavirus illnesses following the introduction of the rotavirus vaccine. Both studies were published this week in Vaccine.
Using insurance database information on children born from 2007 to 2011 (the rotavirus vaccine Rotarix was introduced in the United States in 2006), US and Canadian researchers found that infants who had received at least one dose of the vaccine were significantly less likely than their unvaccinated peers to visit the hospital for rotavirus-related visits. The incidence of rotavirus infection was 17% for fully vaccinated patients compared with the unvaccinated group, and 19% for partially vaccinated children.
Full vaccination status appeared to protect children from diarrhea-related healthcare visits, but children who were only partially vaccinated had similar rates of diarrhea-related inpatient and outpatient visits.
The study conducted in Swaziland showed that introducing the rotavirus vaccine in 2015 was associated with a reduction of the incidence of hospitalization for diarrheal disease of nearly half.
Researchers tested stool samples of children younger than 5 years for rotavirus in a hospital setting and found that, in 2013, 50.8% of samples were positive. By 2016, after vaccine introduction, only 29% of samples tested positive for the virus.
Aug 1 Vaccine US study
Aug 1 Vaccine Swaziland study