Animals keep viruses in the sea in balance

Date: March 27, 2020

Source: Royal Netherlands Institute for Sea Research

A variety of sea animals can take up virus particles while filtering seawater for oxygen and food. Sponges are particularly efficient. That was written by marine ecologist Jennifer Welsh from NIOZ this week, in a publication in Nature Scientific Reports. This Monday, Welsh will defend her thesis at the Free University of Amsterdam, through an online connection.

"When a virus infects a cell," says Jennifer Welsh of the Royal Netherlands Institute for Sea Research (NIOZ), "it uses its host to make new viruses. After those are released, they can, in turn, infect many more, new cells." However, Welsh discovered that the many virus particles in the sea -- over 150 million in a glass of sea water -- can also end up for, a large part, as the lunch of a diverse group of sea animals.

Filtering viruses

The Japanese oyster, for example, filters seawater to extract oxygen or food such as algae and bacteria. While doing this, it ingests virus particles. Welsh: "In our experiments, during which we did not offer the oysters any food and hence they only filtered the water for oxygen uptake, Japanese oysters removed 12 per cent of the virus particles from the water."

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Mosquitoes infected with bacteria to make them infertile released in battle against viruses

When the released males mate with wild female mosquitoes, the resulting eggs will not hatch 

Mythili Sampathkumar New York 

Wednesday 31 January 2018 21:40 GMT

In order to fight Zika and other similar viruses, researchers are going to release thousands of sterilised mosquitoes in south Miami, Florida this week.

Researchers infected the male of the species with a bacteria in a lab and when they mate with females, the resulting eggs will die before hatching.

The Miami-Dade County Mosquito Reduction Test Program is a collaboration from the University of Kentucky and Kentucky-based company MosquitoMate.

The project is an attempt to reduce mosquito populations in the region without artificial genetic modification.

The bacteria used to infect the males, wolbachia, is a naturally-occurring substance in 60 per cent of insects including butterflies and dragonflies.

It is not harmful to humans.

Continued  

Researchers identify mammals that are most likely to harbor viruses risky to humans

June 22, 2017 by Bob Yirka report

(Phys.org)—A team of researchers with the EcoHealth Alliance has narrowed down the list of animal species that may harbor viruses likely to jump to humans. In their paper published in the journal Nature, the group outlines the process they used to collect viral data on mammals around the globe, sorted them into groups and listed where they live. James Lloyd-Smith with the University of California offers a News & Views piece on the work done by the team in the same journal issue.

Scientists know that many of the viral threats we humans will face in the future are likely to come from viruses that already exist but reside in other species, particularly other mammals. The animal hosts have built up some degree of immunity to them, but we have not. Thus, if they jump to us, the result can be devastating. In this new effort, the researchers sought to catalogue all of the known viruses that infect mammals around the globe and identify which are most likely to jump to humans.

To create such a catalogue, the researchers created a database that held information on 754 mammal species, which represented 14 percent of all known mammals. They also added approximately 600 known viruses that infect mammals (of which a third were known to jump to humans) and which animals they infect. Next, they created mathematical models to use information in the database to provide useful information regarding the likelihood of a virus jumping to humans.

The researchers report that their models suggest that the likelihood of a virus jumping from a mammal species to humans depends heavily on species and geography. Bats were found to carry the largest number of viruses likely to jump to humans and the areas where it was most likely to occur were South and Central America. Primates posed the second largest risk factor, particularly in Central America, Africa and Southwest Asia. Rodents came in third with the risk most pronounced in North and South America and Central Africa.

Read more at:

Scientists Prove Ticks Harbor Heartland Virus, a Recently Discovered Disease in the United States

July 22, 2013 — Scientists have for the first time traced a novel virus that infected two men from northwestern Missouri in 2009 to populations of ticks in the region, providing confirmation that lone star ticks are carrying the recently discovered virus and humans in the area are likely at risk of infection. The findings were published online today in the American Journal of Tropical Medicine and Hygiene.

Dubbed Heartland virus or HRTV, the infection causes fever, headaches, and low white blood cell and platelet counts. The two men infected in 2009, who live about 70 miles apart, were sufficiently ill to require hospitalization. They eventually recovered, and no other cases have been reported. Disease experts anticipate, however, that more people could become infected. The Missouri Department of Health and Senior Services is working with the US Centers for Disease Control and Prevention (CDC) to identify additional cases and determine the role of this novel virus as a human pathogen.

Read more

HIV-Like Viruses in Non-Human Primates Have Existed Much Longer Than Previously Thought

Jan. 24, 2013 — Viruses similar to those that cause AIDS in humans were present in non-human primates in Africa at least 5 million years ago and perhaps up to 12 million years ago, according to study published January 24 in the Open Access journal PLOS Pathogens by scientists at Fred Hutchinson Cancer Research Center. Until now, researchers have hypothesized that such viruses originated much more recently.

HIV-1, the virus responsible for AIDS, infiltrated the human population in the early 20th century following multiple transmissions of a similar chimpanzee virus known as SIVcpz. Previous work to determine the age of HIV-like viruses, called lentiviruses, by comparing their genetic blueprints has calculated their origin to be tens of thousands of years ago.

However, other researchers have suspected this time frame to be much too recent. Michael Emerman, Ph.D., a virologist and member of the Human Biology Division at Fred Hutchinson Cancer Research Center, and Alex Compton, a graduate student in the Emerman Lab, describe the use of a technique to estimate the extent to which primates and lentiviruses have coexisted by tracking the changes in a host immunity gene called APOBEC3G that were induced by ancient viral challenges.

Read more:  http://www.sciencedaily.com/releases/2013/01/130124183636.htm

Bats, a Reservoir of Resurgent Viruses

ScienceDaily (July 24, 2012) — Measles, mumps, pneumonia, influenza and encephalitis in man, Carré's disease in dogs, Ovine Rinderpest (PPR)… all of these diseases are caused by viruses from the same family: Paramyxoviridae. A vast international study(1), carried out in collaboration with IRD researchers and published in Nature Communications has led to the discovery of more than 60 new species of these dangerous infectious agents, almost double the number previously recorded. This family of highly diverse pathogens affects all animals, from canines to fowl, cattle and humans. As a result, it is not always easy to determine which host is responsible for these viruses. Thanks to testing carried across the globe, the research team has recently discovered their source: bats.


Continued:  http://www.sciencedaily.com/releases/2012/07/120724104258.htm

Bird Flu Pandemic Facts From The CDC

ForexTV.com (New York) by Conor Kelly

Viruses, like all living organisms are adaptive by nature.  However, they rely upon other organisms, or hosts, to survive and thrive.  The adaptive properties of viruses include the ability to change basic genetic structure to survive within their host.  Despite very rare cases of H5N1 viruses in humans, medical experts are becoming increasing concerned that the H5N1 virus could mutate, or adapt to human hosts and become more transmittable between humans.  In the case of the H5N1, or bird-flu the virus is most virulent in avian animals.  According to the Center for Disease Control (CDC) these include: 

·         Avian influenza A viruses have been isolated from more than 100 different species of wild birds from around the world. Most of these viruses were low pathogenic avian influenza A viruses.

·         The majority of these wild birds have been aquatic birds, including gulls, terns, and shorebirds, or waterfowl such as ducks, geese and swans. These wild birds are considered reservoirs (hosts) for avian influenza A viruses.

• Around the world, avian influenza A outbreaks occur among poultry from time to time.
• Currently, highly pathogenic avian influenza (HPAI) A (H5N1) virus is considered endemic among poultry in six countries (Bangladesh, China, Egypt, India, Indonesia, and Vietnam). This means the virus is commonly found in poultry in those countries. Sporadic outbreaks have occurred among poultry in other countries.

Bird flu in humans is very rare.  Since 2003, approximately 606 cases of bird flu have been reported world-wide.  However, those known infections carried a 60% mortality rate, mostly in adolescents between the ages of 11-18 and the elderly.  Although rare the CDC says that Avian influenza A viruses may be transmitted from animals to humans in two main ways:

·         Directly from birds or from avian influenza A virus-contaminated environments to people.

·         Through an intermediate host, such as a pig.

HPAI H5N1 viruses circulating among birds have evolved and are continuing to evolve into different subgroups of viruses, called ‘clades.’ Notably, there are geographic differences in the circulation of some HPAI H5N1 viruses. Because HPAI H5N1 viruses are evolving in unpredictable ways, it is critical to monitor the spread and circulation of these viruses among poultry and other birds, in order to understand the risk of spread to humans.

Now, scientists have engineered versions of the H5N1 bird flu that spread easily among mammals through droplets in sneezes and have concluded that the deadly virus could trigger a global pandemic in humans.

Vaccination and Treatment for HPAI H5N1 in Humans

HPAI H5N1 vaccine is being stockpiled for pandemic preparedness by the United States government. It is not currently available for use. It could be used if an HPAI H5N1 virus begins transmitting easily and efficiently from person to person.

Oseltamivir remains the primary recommended antiviral drug for treatment and chemoprophylaxis for HPAI H5N1.

http://www.forextv.com/forex-news-story/bird-flu-pandemic-facts-from-the-cdc

Rabies Snoozes While Bats Hibernate

How quickly deadly viruses evolve depends on many factors, new research suggests. For instance, rabies evolves slower while bats are hibernating. This means it also varies by location, since bats in the tropics don't hibernate.

Rabies viruses in tropical and sub-tropical bat species evolved nearly four times faster than those in bats in temperate regions.

"Species that are widely distributed can have different behaviors in different geographical areas," study researcher Daniel Streicker, of the University of Georgia, said in a statement. "Bats in the tropics are active year-round, so more rabies virus transmission events occur per year. Viruses in hibernating bats, on the other hand, might lose up to six months' worth of opportunities for transmission."

Viral evolution
Understanding the relationship between host ecology and viral evolution rates could reveal details about other viruses, such as influenza, that occur across regions, infect multiple host species or whose transmission dynamics are impacted by humans.

"If viral evolution is faster, it could potentially lead to greater genetic diversity in crucial parts of the viral genome that allow it to shift hosts," Streicker said. "For rabies, we don't yet know what those are, so identifying them will be key. Similarly, before understanding whether climate change will speed viral evolution, we need a better idea of how environmental changes will influence host ecology and behavior."

Continued:  http://www.livescience.com/20442-rabies-snoozes-bats-hibernate.html

Bats: An Unexpected Virus Reservoir

ScienceDaily (Apr. 24, 2012) — Where do viruses dangerous to humans come from, and how have they evolved? Scientists working with Prof. Dr. Christian Drosten, Head of the In¬stitute for Virology at the Universitätsklinikum Bonn, have made significant progress in answering this question. "We already knew from prior studies that bats and rodents play a role as carriers of paramyxoviruses," said Prof. Drosten. The many varied members of this large virus family cause, e.g., measles, mumps, pneumonias and colds. The highly dangerous Hendra and Nipah viruses cause types of encephalitis that result in death for one out of two patients. Paramyxoviruses also play a role in veterinary medicine, causing e.g., canine distemper or rinderpest.

Researchers double the number of known paramyxovirus species

With support from numerous scientific institutes in Germany and around the world, they tested a total of 9,278 animals from Europe, South America and Asia, including 86 bat and 33 rodent species. "These animals live in very large social communities with millions of individuals in some cases," reported the Bonn virologist. "Their close contact promotes mutual infection and provides for great variety in circulating viruses." Using molecular biology methods, the scientists identified which virus species are rampant in bats and rodents. According to their own estimates, they discovered more than 60 new paramyxovirus species. "That is about as many as the number that was already known," said Drosten.

Continued:  http://www.sciencedaily.com/releases/2012/04/120424120539.htm

American parents caught selling chickenpox-infected lollipops

American parents have been caught selling chickenpox-infected lollipops to other families who want their children to catch the virus while they are young.

Prosecutors in Tennessee have been forced to issue a warning that sending viruses or diseases by post is illegal, after parcels of the infectious sweets were discovered on sale over the internet.

Wendy Werkit, of Nashville, offered to send other parents a "fresh batch of pox" on lollipops or cotton-buds in return for $50 (£31) via PayPal.

Mrs Werkit told a local television station that she had been inspired to sell the products because parents were frustrated that "they can't get it the normal way any more".

Her advertisement was placed on a Facebook page intended to help parents find a "pox party" in their local area, where children can mix and pick up the virus, which can be more dangerous if suffered later.

Advice for the best way to send chickenpox emerged in a thread of postings on the site. "Tuck it inside a ziplock baggie then put it in the envelope," it said. "Don't put anything identifying it as pox."

Jerry Martin, the US attorney for the Middle District of Tennessee, condemned the practice and said that it was a federal crime to send diseases or viruses across state lines.

"If you are engaged in this type of behaviour, you're not only potentially exposing innocent people to dangerous viruses and illnesses and diseases, you're also exposing yourself potentially to federal criminal prosecution," he said.
http://www.telegraph.co.uk/health/healthnews/8875158/American-parents-caught-selling-chickenpox-infected-lollipops.html

Animal genomes riddled with the 'skeletons' of ancient viruses

It’s time for animals - including humans - to admit that the bacteria, viruses and other microbes have won. Our bodies are home to many times more bacterial cells than animal cells and countless trillions of viruses. Ancient retroviruses make up a good size chunk of our genome. Now, scientists have discovered that most any virus can set up shop in an animal's genomes and lay dormant for millions of years.


A scan of 44 mammal genomes, plus those of several mosquito and tick vectors and two birds that could serve as reservoirs, has uncovered DNA sequences that can be traced to 10 different families of viruses, including some related to viruses that cause hepatitis B, Ebola, rabies and dengue. Most of the viral sequences are riddled with enough mutations to be considered junk, but some appear to encoding working genes co-opted by their host. The work is published online today in the journal PLoS Genetics.

It’s not obvious how all these viruses got into animal genomes. The researchers, Aris Katzourakis at the University of Oxford, UK, and Robert Gifford at Rockefeller University in New York, searched specifically for viruses that aren’t retroviruses, which are obligated to copy their DNA into hosts. Many but not all of the viruses infect their hosts persistently or replicate inside of the nucleus, however, offering ample opportunity to take up residence in the genomes of germ cells.

The work is just a first look at all the non-retroviruses in the animal genome, but Katzourakis and Gifford turned up a few interesting findings. For instance, their scan identified sequences from filoviruses, the family Ebola belongs to, in the genomes of bats, tarsiers, several rodents, opossums and even wallabies. This hints that filoviruses have a much wider host range than the primate and bat species which these viruses are known to infect.

The paper also hints at unknown ancient transmissions of viruses between hosts. The bottlenose dolphin genome, it turns out, is home to sequences of a kind of parvovirus similar to one found in birds, suggesting that the viruses may have jumped between mammals and birds in the past.

Most of these sequences are junk, so filled with mutations that they can’t make working proteins. But some of the viral sequences might do something inside their hosts. One example is a bornavirus gene called EBLN-1 that took up residence in ancient primate genomes some 50 million years ago and survives intact in many modern primates, including humans. A similar protein latches onto RNA in bornaviruses, so it might do the same in primates as part of a viral defence mechanism, Gifford speculates.

Like the ancient retroviruses locked inside animal genomes, these viruses offer a window into infections that occurred millions of years ago.

“People who are looking at the ecology of those diseases, they very much work in recent time and they have no assumptions that it’s an old system that might have evolved over billions of years,” says Gifford. "The data that we’re finding is really contradicting that and providing the first evidence that these are really old relationships between hosts and viruses, and I think it’s really critical to how we underestand them to get that context right."