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rjzimmerman · 4 years

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Honeybees are having their own pandemic, which is another sledge hammer against human civilization.....we need bees. This story tells us that the absence of social distancing and touching their faces does a number on honeybee colonies. Sounds familiar.

Excerpt from this story from EcoWatch:

Honey bees guarding the entrances to their respective hives are twice as likely to allow access to virus-infected trespassers, suggesting that the pathogen is capable of altering the insect's behavior and physiology to boost its spread to neighboring colonies.

Israeli acute paralysis virus (IAPV) is a widespread virus that has been linked with colony losses, such as the mysterious outbreak of honey bee Colony Collapse Disorder across the U.S. Publishing their work in Proceedings of the National Academy of Sciences, researchers at the University of Illinois at Urbana-Champaign determined that the virus is capable of changing certain host behaviors and physical traits, particularly in social contexts, of one of the world's most critical pollinators.

"The most important finding of our study is that IAPV infection increases the likelihood that infected bees are accepted by foreign colonies," said lead study author and professor of entomology Adam Dolezal. "Somehow, the infected bees are able to circumvent the guards of foreign colonies, which they shouldn't be able to do."

IAPV is considered a "category of concern" and previous research has shown that honey bees infected with the virus are more likely to get lost when returning to their home hives. To determine how the pathogen manipulates host behavior, researchers built on previous work that employed an automated system to study bees' use of trophallaxis, the regurgitation of food and other liquids to feed colony members.

"Honey bees use trophallaxis to share food with each other as well as hormones and other signaling molecules that can affect their physiology and behavior. They do it in pairs by touching their mouthparts and antennae, and each bee does this with hundreds of partners a day," said study co-author and entomologist Gene Robinson.

"Trophallaxis is essential to the spread of information and nutrition throughout the hive, but unfortunately, a behavior performed with such close social contact also allows viral infections to be transmitted through a hive."

Bees were tagged with a barcode for continuous monitoring to determine how IAPV affects the use of trophallaxis. Observations showed that individuals infected with IAPV were just as mobile but engaged less in trophallaxis with home colony members, which protected their hive from viral infection. However, when a honey bee was placed at the entrance of a foreign hive, bees were more likely to engage through trophallaxis with guards – and those guards were then more likely to permit hive entrance to infected bees than healthy ones.

#honeybees #Israeli acute paralysis virus (IAPV)#bee pathogens

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beekeepingfiji · 4 years

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Disease Survey of Honey Bees in Vanuatu - PHAMA Technical Report 34

New Post has been published on https://www.beekeepingfiji.com/?p=3987

Disease Survey of Honey Bees in Vanuatu - PHAMA Technical Report 34

An AusAID initiative is to increase exports of high value primary products from Pacific Island Countries (PICs). The Pacific Horticultural and Agricultural Market Access Program (PHAMA) is designed to address constraints to market access for primary production products, including honey and other bee products. PHAMA funded the current bee disease survey to support the growth of the beekeeping industry in Vanuatu by establishing the disease status of the local honey bees and using this information as a basis for quarantine regulations and market access negotiations.

The bee disease survey was carried out by Byron Taylor and Tony Roper, AsureQuality Limited, New Zealand, from 17–27 October 2012. The last bee disease survey conducted in Vanuatu was done by Bettesworth and Grueber in 2000.

Gilbert Gibson has the largest hive holding in Vanuatu, currently managing approximately 250 colonies. A second beekeeper, Ian Shaw, operates around 70 colonies, and a number of individuals operate less than 6 hives.

Apiary Industry in Vanuatu

It is estimated that there are around 400 managed colonies in Vanuatu, with 90% or more on Efate. The annual honey crop is approximately 5 tonnes per year, all of which is consumed within Vanuatu. The estimated consumption is around 10 tonnes, with the shortfall being made up with imports of honey from Australia and France (Gilbert Gibson, pers. comm.).

Gilbert Gibson has been beekeeping in Vanuatu for many years but has recently moved to full-time beekeeping. It is his hope to increase his current hive numbers to increase production for local consumption in the short term, with the potential to move into export markets in the long term.

In addition to European bees, the Asian Honey Bee (Apis cerana) has recently been discovered on Efate. It is unsure how long Apis cerana has been in Vanuatu but, judging by its distribution and comments from Gilbert Gibson, anywhere from 2 to 4 years is realistic.

A component of the current survey was to assess the spread of Apis cerana and, in particular, whether it is present on the islands of Espiritu Santo, Malekula and Tanna.

Currently, honey and other bee products entering New Zealand from a number of PICs must be accompanied by a zoosanitary certificate issued by the veterinary authority of the exporting country which certifies that:

The honey originates from that country; and

The country is free from European foulbrood (EFB) caused by Melissococcus pluton. 1

Vanuatu is not included on the list of PICs covered by this import health standard (IHS), so access to New Zealand would need to be separately negotiated.

New Zealand’s Ministry for Primary Industries (MPI), formerly the Ministry of Agriculture and Forestry, revised the IHS for Specified Processed Bee Products in June 2009. However, this standard is on hold while issues with a similar IHS for bee products from Australia are resolved.

European foulbrood (EFB)

EFB is a bacterial disease that affects the developing brood and is controlled in many countries by feeding antibiotics to beehives. EFB-causing bacteria can be transmitted in bee products, especially honey and pollen.

EFB disease has never been detected in Vanuatu or New Zealand but regular surveys by competent personnel, and reporting to international authorities, are required to confirm this status. EFB is present in Australia.

In addition, honey exported to the European Union must come from apiaries of known disease history. This usually means an apiary database is being maintained annual bee disease surveys are being carried out, and beekeepers are reporting on the presence of listed bee diseases.

The survey team inspected 193 beehives

The survey team inspected 193 beehives for bee diseases and pests, in particular EFB and its associated secondary bacterium Paenibacillus alvei.

Samples were also taken from 34 hives for testing for Deformed Wing Virus (DWV) and four known strains of Israeli Acute Paralysis Virus (IAPV), the microsporidian Nosema ceranae, the internal or tracheal mite Acarapis woodi and the external mites Varroa sp and Tropilaelaps.

All these diseases, except DWV, A. woodi and the external mites, were raised as pathogens of concern by the beekeeping industry in New Zealand following the risk analysis done by MPI to allow heat-treated honey from Australia into New Zealand. DWV was found in New Zealand in 2007, and A. woodi and the external mites Varroa sp and Tropilaelaps are not transmitted in honey.

Varroa destructor is endemic in New Zealand. Since the IHS was reviewed, MPI has confirmed the presence of P. alvei and Nosema ceranae in New Zealand. A nationwide survey, plus ongoing annual sampling and testing, has not detected the presence of IAPV in New Zealand, and it remains a bee disease of concern with New Zealand beekeepers (McFadden, Tham et al 2012).

Bees were tested for DWV, Nosema ceranae, the tracheal mite and Varroa spp and Tropilaelaps, in case Vanuatu is in a position to export live bees, queen cells or drone semen in the future. However, the presence of Apis cerana and Varroa jacobsoni could limit the export potential of this material.

No cases of EFB or American foulbrood (AFB) were detected, despite a case of AFB being discovered in the previous survey in 2000 and an additional case being discovered earlier this year by Mr Gilbert Gibson and Mr Nambo Moses. The recent find was in the same area as the original discovery in 2000.

American foulbrood (AFB)

AFB is one of the most widespread and serious honey bee diseases in the world. This disease is endemic in New Zealand and is controlled by inspection and total destruction of infected material.

Some approved beekeepers can recover infected equipment by dipping in paraffin wax heated to 1600C for at least 10 minutes. AFB is subject to a Pest Management Strategy in New Zealand. It is recommended that for Vanuatu, AFB is included in an annual surveillance program and that any infected material found is destroyed.

Varroa jacobsoni

Varroa jacobsoni was identified in European honey bee colonies during the survey. Samples of these mites were taken for morphological and molecular analysis, which confirmed the identification.

The survey in Vanuatu achieved a hive inspection rate of 48% and a hive sampling rate of 8.5%, from a population of approximately 400 hives. New Zealand has a target inspection rate of 1.4% of hives under its exotic honey bee disease surveillance program. However, all hives in New Zealand must be inspected for AFB disease each year by an approved beekeeper, which increases the possibility of beekeepers finding a notifiable exotic bee disease or pest.

The survey team inspected 46 apiaries and 21 feral colony locations. While there is no official apiary register, it is estimated that we inspected around 80% of managed apiaries, compared to New Zealand’s target surveillance rate of 2.6%.

Apis cerana (Asian Honey Bee)

Apis cerana was confirmed on Efate and the two nearby islands of Pele and Emao, which lie north of Efate. Four samples were collected (three from Efate and one from Emao) and submitted to the laboratory for testing. These colonies were subjected to a brood inspection where possible.

Apis cerana was not detected on Santo, Malekula or Tanna. Eradication of the Asian bees (Apis cerana) from Efate, Pele and Emao is not feasible; however, awareness raising measures such as posters at ports and pamphlets for commercial and recreational sailors could help to reduce the chance of the Asian bees spreading between islands.

Laboratory analysis of bee samples did not detect any cases of DWV and IAPV, the tracheal mite Acarapis woodi, or the external mites Varroa destructor and Tropilaelaps. The external mites Acarapis externus and Acarapis dorsalis were detected on many bees. These mites are common in New Zealand and are not known to cause any damage to honey bees.

Nosema ceranae

The microsporidian Nosema ceranae was detected by polymerase chain reaction (PCR) in 13 of the 24 apiaries tested (54%). Previous surveys did not test for the presence of Nosema ceranae, so it is unclear how long it has been present in Vanuatu. Nosema ceranae has only recently been confirmed in New Zealand using PCR technology. It is not known what effect, if any, this species of nosema is having on honey bees either in New Zealand or in Vanuatu.

EFB disease has never been reported in Vanuatu and no evidence of this disease was found during this survey or during past surveys. No cases of tracheal mites or the Small Hive Beetle were found. There was no evidence of the African honey bee (Apis mellifera scutellata) or the Cape honey bee (Apis mellifera capensis). These diseases or pests are not transmitted through honey.

Other minor diseases were reconfirmed as being present, such as both the greater and lesser wax moths (which exist in New Zealand). Various species of ants, cockroaches, centipedes and lizards living in or around hives were also found, but these are not transmitted live in honey.

The risk pathways into Vanuatu

The risk pathways into Vanuatu for an exotic honey bee disease or pest are considerable, with ongoing importation of honey from France and Australia, regular shipping and air flights from a number of countries, plus visiting cruise ships and yachts, which could have honey on board.

The number of tourists representing a risk visiting Vanuatu has dropped slightly in recent years but has grown considerably since the last survey was completed.

As an indication, the number of accommodation rooms available almost doubled from 800 to more than 1500 between 2005 and 2011 (http://www.tms.com.vu/statisitics1.html).

Importation of honey into Vanuatu

Importation of honey into Vanuatu is managed under the “Animal Importation and Quarantine Act, 1988” and the “Animal Importation and Quarantine Regulations, 1994”. These documents require that honey imports are accompanied by an import permit which states:

“Permission for import is granted under the following conditions:

Contain no substances harmful to human health;

Have been processed, prepared, packaged, and transported according to the required public health legislation in the country of origin;

Have been heat treated or pasteurised;

No raw honey or combs are permitted entry.”

In order to retain stability in the local market as honey production increases, it will be necessary to investigate export opportunities. Export to New Zealand is currently allowed from some PICs; however, Vanuatu is not included in this IHS.

If Vanuatu were to negotiate its own conditions, New Zealand would likely require similar conditions to those currently imposed on other PICs.

This includes attesting to the country of origin of the product and certifying that Vanuatu is free of EFB. A surveillance program to address this issue is recommended and discussed in more detail in the report.

This surveillance program could also support the negotiation of export protocols to other export markets.

Disease Survey of Honey Bees in Vanuatu – PHAMA Technical Report 34

Download Disease Survey of Honey Bees in Vanuatu – PHAMA Technical Report 34

Disease Survey of Honey Bees in Vanuatu – PHAMA Technical Report 34 Download

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tachtutor · 4 years

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Virus-Infected Bees Practice Social Distancing

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If there’s one thing we know about viruses, it’s that they love to spread. The novel coronavirus is happy to use us humans as its host. Other viruses fancy honeybees. But like us, bees fight back.

In the case of one particular virus, called Israeli acute paralysis virus, a study shows that honeybees actually use a form of social distancing to prevent transmitting the infection within…

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chhatramani · 4 years

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Virus-infected honey bees more likely to gain entrance to healthy hives Latest Science News -- ScienceDaily Virus-infected honey bees more likely to gain entrance to healthy hives #EngineeringCy Honey bees that guard hive entrances are twice as likely to allow in trespassers from other hives if the intruders are infected with the Israeli acute paralysis virus, a deadly pathogen of bees, researchers report.

#Engineering Cy

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savethebeesdeb · 5 years

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Bee Conservation

Did you know that a commonly used pesticide is causing our fellow bees to die?

Neonincotinoids

Neonicotinoids is a toxic chemical that is used to maintain our garden and crops.

Now you may think to yourself, “How does this affect the bees?”

This chemical is used to help protect our crops from insects and mites who eat crops. It’s also used to keep weeds from overgrowing. This pesticide is used by farmers, gardeners or even homeowners in order to keep insects from eating plants and flowers.

This chemical is is sprayed onto crops and it gets absorbed by the plant.

Once the plant fully grows, a bee will pollinate the plant and intake the toxic chemical as well.This chemical is present in pollen and nectar, making it harmful for bees.

Another way it can harm bees is when farmers spray this toxic chemical onto crops, a bee may fly into a dusk of neonicotinoids and intake the chemical.

Israeli Acute Virus

Scientist also believe that viruses are another contributing factor to Colony Collapse Disorder.

One example would be Israeli acute paralysis virus.

Now you may think to yourself, “What is this virus exactly?”

This virus spread among honey bees and has been linked to colony losses around the world. This virus causes the wings of bees to shiver and darkened hairless abdomen, progressing into paralysis and then death. Researchers have performed a few studies by examining a healthy hive and fed the bees sugary water laden with Israeli acute paralysis virus in order for the bees to mimic some symptoms of Colony Collapse Disorder.

And the results were...Yes! The bees did mimic symptoms

But additional sampling was done and it was seen that some bees who had this virus were able to naturally get rid of the virus. This concludes that this virus is just a contributing factor.

Nosema Bombi

Another contributing factor to Colony Collapse Disorder is Nosema Bombi. This is a unicellular parasite that affects bumble bees. The parasite can be found in the gut lumen and Malpighian tubules of the infected bees’. It’s released into the environment through feces and decaying bee.

How can this parasite spread to other bees?

Scientist believe that commercial bees, which are bees who are strictly used to pollinate crops in a green house somehow find a way out and pollinate the same plant as wild bees.

Another way this parasite can spread is though feces, which is basically bee poop and a decaying bee,

Fun fact: Did you know that bees are clean insects! They don’t use the bathroom inside their hive, instead they go outside!

So lets sum of some of the many contributing factors to Colony Collapse Disorder.

1. Parasite

2.Pesticide

3.Virus

Remember, there are MANY other contributing factors, but scientist have NOT found the primary factor!

The link below will explain more how pesticide is harmful to our fellow pollinators!

youtube

#savethebees

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sciencespies · 4 years

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Honey Bee Virus Tricks Hive Guards Into Admitting Sick Intruders

https://sciencespies.com/news/honey-bee-virus-tricks-hive-guards-into-admitting-sick-intruders/

Honey Bee Virus Tricks Hive Guards Into Admitting Sick Intruders

Honey bees are known for running a tight ship. Their hexagonal honeycombs make the most mathematically efficient use of space for storing honey, they keep diseases from spreading by minimizing touching or feeding of sick hive-mates, and guards stationed at the hive entrance act as bouncers to keep out intruders.

But new research suggests a deadly virus tricks those normally vigilant guards into letting infected invaders into their hives, reports Erik Stokstad for Science.

“Somehow, the infected bees are able to circumvent the guards of foreign colonies, which they shouldn’t be able to do,” says Adam Dolezal, an entomologist at the University of Illinois and leader of the new research, in a statement.

The virus, called Israeli acute paralysis virus (IAPV), has also been shown to make forager bees more likely to get lost on their way home—upping their chances of spreading the virus to a neighboring hive.

By enabling these wandering bees to slip past an unfamiliar colony’s defenses, the virus has evolved a way to spread despite the sophisticated tactics bees deploy inside their colonies to tamp down infections.

“This is an interesting study that demonstrates an arms-race between a honey bee host and its viral pathogen at the behavioral level,” Eyal Maori, a virologist at Cambridge University who was not involved in the research, tells Rosie McCall of Newsweek.

IAPV infections have been linked to colony losses and are one of many environmental stresses—including parasitic mites, pesticides, pollution and loss of plant diversity—making life more difficult for some of the insect world’s hardest working farmhands. Without honey bees, roughly a third of the food eaten by Americans would disappear. Bees’ contributions to pollinating crops including apples, melons, cranberries, pumpkins, squash, broccoli and almonds are valued at more than $15 billion.

This new research suggests that the practice of stacking multiple hives next to each other in commercial beekeeping may play right into the hands of IAPV. Left to their own devices, bees tend to spread out, with just one or two hives per square mile.

Dolezal and his team wanted to study how IAPV spreads and had a hunch that it might make some strategic alterations to the behavior and physiology of infected bees. To track the insects’ behavior, the team tagged bees with barcode-like labels that could then be recognized and tracked by cameras attached to an automated computer system.

The system, capable of tracking up to 900 bees at once, was programmed to spot a behavior called trophallaxis, in which two bees smush their faces together while sharing regurgitated food and transmitting hormones or other chemical messages.

“Trophallaxis is essential to the spread of information and nutrition throughout the hive, but unfortunately, a behavior performed with such close social contact also allows viral infections to be transmitted through a hive,” says Gene Robinson, an entomologist at the University of Illinois and study co-author, in a statement.

youtube

The researchers used the automated system to track the behaviors of 90 to 150 IAPV-infected bees released into an experimental hive. The study found that bees infected with IAPV, as well as bees with stimulated immune systems designed to mimic infection, were shunned by their hivemates when they went looking for trophallaxis, the researchers report this week in the journal Proceedings of the National Academy of Sciences.

But the bees’ brand of social distancing inside the hive wasn’t enough to protect them from the virus. When the team placed individuals infected with IAPV outside a hive, the guards gave them special treatment—letting them in more often and engaging in more trophallaxis with them than with healthy or immune-stimulated bees.

The researchers suspect the guards’ sweet spot for the sick bees may be because of their smell, which is used by the guards to discern friend from foe. The researchers found that smelly compounds called hydrocarbons were chemically altered in bees infected with the virus. But these sick bees may slip past the velvet rope by simply being nicer to the guards, reports Science. The researchers observed sick bees being more submissive and sharing more food when approached by hostile guards.

The findings suggest that IAPV is evolving to infect as many hosts as possible, says Dolezal in a statement.

Other researchers say IAPV’s ability to modify the bees’ behavior to get from hive to hive might also increase the spread of additional threats. IAPV could aid the transmission of pathogens and pests, such as the varroa mite, to new colonies, Maori tells Newsweek. The mite feeds on bees’ fat reserves and has devastated colonies across the world.

More research is needed to determine if IAPV plays a big role in the spread of mites and other viruses, Maori tells Newsweek, which would represent a significant vulnerability in commercial beekeeping operations that keep many hives close together.

#News

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thatssorue · 4 years

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Virus-infected honey bees more likely to gain entrance to healthy hives

#Nature's Incredible!

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milkdongcomics · 4 months

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World Bee Day 2024 世界蜜蜂日 ANIMAN - SICK BEE HEY HUMAN, SEE WHAT YOU DO!? Pre-order: https://a.co/d/6SrfkMf Instagram: milkdongcomics Facebook: Milk DoNg Comics

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frankkjonestx · 4 years

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Virus-infected honey bees more likely to gain entrance to healthy hives

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ruggerorespigo · 4 years

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Virus-infected honey bees more likely to gain entrance to healthy hives

Honey bees that guard hive entrances are twice as likely to allow in trespassers from other hives if the intruders are infected with the Israeli acute paralysis virus, a deadly pathogen of bees, researchers report. Latest Science News -- ScienceDaily https://www.sciencedaily.com/releases/2020/04/200427184138.htm

#IFTTT #Latest Science News -- ScienceDaily #ruggero respigo

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sciencebulletin · 4 years

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Virus-infected honey bees more likely to gain entrance to healthy hives

Honey bees that guard hive entrances are twice as likely to allow in trespassers from other hives if the intruders are infected with the Israeli acute paralysis virus, a deadly pathogen of bees, researchers report. Their new study, reported in the Proceedings of the National Academy of Sciences, strongly suggests that IAPV infection alters honey bees' behavior and physiology in ways that boost the virus's ability to spread, the researchers say. "The most important finding of our study is that IAPV infection increases the likelihood that infected bees are accepted by foreign colonies," said Adam Dolezal, a professor of entomology at the University of Illinois at Urbana-Champaign who led the new research. "Somehow, the infected bees are able to circumvent the guards of foreign colonies, which they shouldn't be able to do." Previous studies have shown that IAPV-infected honey bees are more likely than healthy bees to lose their way when returning home from foraging trips. In commercial beekeeping operations where hives are stacked much closer together than in the wild, the virus is even more likely to spread from one infected colony to nearby healthy ones. To capture the behavior of individual bees, researchers tagged each one with the equivalent of a QR code and continuously monitored their interactions. The scientists were able to simultaneously track the behaviors of as many as 900 bees. In previous work, study co-author U. of I. entomologist Gene Robinson and his colleagues developed this automated system to study bees engaged in trophallaxis, a process by which honey bees exchange regurgitated food and other liquids. They used this system to study how IAPV infection might affect the bees' trophallaxis social network. "Honey bees use trophallaxis to share food with each other as well as hormones and other signaling molecules that can affect their physiology and behavior. They do it in pairs by touching their mouthparts and antennae, and each bee does this with hundreds of partners a day," said Robinson, who directs the Carl R. Woese Institute for Genomic Biology at Illinois. "Trophallaxis is essential to the spread of information and nutrition throughout the hive, but unfortunately, a behavior performed with such close social contact also allows viral infections to be transmitted through a hive." In the new study, the scientists saw that honey bees altered their behavior in response to infection in their own hives. IAPV-infected bees—and bees that had had their immune systems stimulated to mimic infection—engaged in less trophallaxis than their healthy counterparts did. The infected bees were just as mobile as the other bees, so their lower rates of trophallaxis were not the result of sluggishness from being sick, Dolezal said. The researchers believe this change in behavior is a general response to a health threat and not specific to IAPV infection, which is in line with previous research. When the scientists placed honey bee workers at the entrance of a foreign hive, however, the infected bees engaged in more trophallaxis with the guards, the researchers found. The guards were more likely to admit them than to let in healthy bees or bees whose immune systems had been stimulated. This response was specific to IAPV infection. "Something about them must be different," Dolezal said. To test whether the IAPV-infected bees were giving off a different chemical odor than their healthy nest mates, the researchers analyzed the chemistry of the hydrocarbons that coat the bees' exoskeletons. They discovered distinct hydrocarbon profiles for healthy bees, IAPV-infected bees and immunostimulated bees. "It seems that the virus is changing how the bees smell, and perhaps the infected bees also are behaving in a way that is meant to appease the guards by engaging more in trophallaxus," Dolezal said. The new findings suggest that IAPV is evolving in ways that enhance its ability to infect as many hosts as possible, Dolezal said. "If you're a virus, it's much more valuable to get transmitted to a new family group, like traveling from one city to a new city," he said. "And so how do you get there? You increase the chances that the sick bees leaving colony A are more likely to get into colony B." Provided by: University of Illinois at Urbana-Champaign More information: Amy C. Geffre et al. Honey bee virus causes context-dependent changes in host social behavior. PNAS (2020). Image: Entomology professor Adam Dolezal and his colleagues found that infection with the Israeli acute paralysis virus increases the likelihood that infected bees are accepted by foreign colonies. Credit: Fred Zwicky Read the full article

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scienceblogtumbler · 4 years

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Virus-infected honey bees more likely to gain entrance to healthy hives

Their new study, reported in the Proceedings of the National Academy of Sciences, strongly suggests that IAPV infection alters honey bees’ behavior and physiology in ways that boost the virus’s ability to spread, the researchers say.

“The most important finding of our study is that IAPV infection increases the likelihood that infected bees are accepted by foreign colonies,” said Adam Dolezal, a professor of entomology at the University of Illinois at Urbana-Champaign who led the new research. “Somehow, the infected bees are able to circumvent the guards of foreign colonies, which they shouldn’t be able to do.”

Previous studies have shown that IAPV-infected honey bees are more likely than healthy bees to lose their way when returning home from foraging trips. In commercial beekeeping operations where hives are stacked much closer together than in the wild, the virus is even more likely to spread from one infected colony to nearby healthy ones.

To capture the behavior of individual bees, researchers tagged each one with the equivalent of a QR code and continuously monitored their interactions. The scientists were able to simultaneously track the behaviors of as many as 900 bees.

In previous work, study co-author U. of I. entomologist Gene Robinson and his colleagues developed this automated system to study bees engaged in trophallaxis, a process by which honey bees exchange regurgitated food and other liquids. They used this system to study how IAPV infection might affect the bees’ trophallaxis social network.

“Honey bees use trophallaxis to share food with each other as well as hormones and other signaling molecules that can affect their physiology and behavior. They do it in pairs by touching their mouthparts and antennae, and each bee does this with hundreds of partners a day,” said Robinson, who directs the Carl R. Woese Institute for Genomic Biology at Illinois. “Trophallaxis is essential to the spread of information and nutrition throughout the hive, but unfortunately, a behavior performed with such close social contact also allows viral infections to be transmitted through a hive.”

In the new study, the scientists saw that honey bees altered their behavior in response to infection in their own hives. IAPV-infected bees – and bees that had had their immune systems stimulated to mimic infection – engaged in less trophallaxis than their healthy counterparts did.

Photo by Tim Gernat

Researchers tagged each honey bee with the equivalent of a QR code and used an automated system to study trophallaxis, a process by which the bees exchange regurgitated food and other liquids. The system allowed them to track how infection with IAPV affected the bees’ trophallaxis social network.

The infected bees were just as mobile as the other bees, so their lower rates of trophallaxis were not the result of sluggishness from being sick, Dolezal said. The researchers believe this change in behavior is a general response to a health threat and not specific to IAPV infection, which is in line with previous research.

When the scientists placed honey bee workers at the entrance of a foreign hive, however, the infected bees engaged in more trophallaxis with the guards, the researchers found. The guards were more likely to admit them than to let in healthy bees or bees whose immune systems had been stimulated. This response was specific to IAPV infection.

“Something about them must be different,” Dolezal said.

To test whether the IAPV-infected bees were giving off a different chemical odor than their healthy nest mates, the researchers analyzed the chemistry of the hydrocarbons that coat the bees’ exoskeletons. They discovered distinct hydrocarbon profiles for healthy bees, IAPV-infected bees and immunostimulated bees.

“It seems that the virus is changing how the bees smell, and perhaps the infected bees also are behaving in a way that is meant to appease the guards by engaging more in trophallaxus,” Dolezal said.

The new findings suggest that IAPV is evolving in ways that enhance its ability to infect as many hosts as possible, Dolezal said.

“If you’re a virus, it’s much more valuable to get transmitted to a new family group, like traveling from one city to a new city,” he said. “And so how do you get there? You increase the chances that the sick bees leaving colony A are more likely to get into colony B.”

The Christopher Family Foundation, National Academies Keck Futures Initiative, American Pollinator Protection Campaign and U.S. Department of Agriculture’s National Institute of Food and Agriculture supported this research.

source https://scienceblog.com/515892/virus-infected-honey-bees-more-likely-to-gain-entrance-to-healthy-hives/

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