Hurricane Matthew, a destructive hurricane that traveled from the Caribbean to the United States impacting Florida and the Carolinas, has been recently buzzing in the news. As the hurricane receded, it has left standing bodies of water in Florida, a state that is most impacted by Zika. Damages in infrastructure have allowed mosquitoes to surreptitiously breed in areas such as broken poles, damaged gutters, etc. Although the hurricane itself may have temporarily decreased the mosquito population, those that survive will be able to take advantage of excellent breeding conditions. This theory is postulated because the number of West Nile cases doubled after the 2008 hurricane impacting Louisiana. Additionally, one must consider that human behavior and priorities change after a natural disaster. People impacted about the hurricane care more about opening the door inside a house with broken AC, fixing pipelines, and retrieving lost items, more than wearing insect repellent, wearing long sleeves, and avoiding standing bodies of water.
The hurricane has also impeded with mosquito control efforts that were already implemented in South Florida. As a first step to recovering after the hurricane, Florida Governor Rick Scott has asked residents to immediately address and eliminate standing bodies of water. However, addressing mosquito control measures for Zika do not currently remain as an important priority on the Florida Political Agenda.
Check out the article here: http://www.mcclatchydc.com/news/nation-world/national/article107108352.html
~Michelle Bach (Humans and Viruses 2016-2017)
Monday, October 10, 2016
Nanotube Array: Technology for Identifying New (Forms of) Viruses
One part of studying viruses is being on pace with them- being able to identify both new strains of known viruses and emerging viruses. So far, using PCR (polymerase chain reaction), virus isolation, and next-generation sequencing have been important tools. However, if only minute counts of a virus exists in a field sample, it could easily be overlooked.
A bioengineering group led by Si-yang Zheng and Mauricio Terrones has been working to increase our ability for virus surveillance and discovery. The nanotube array is a device that enriches the concentration of virus in field sample at least hundred-fold, by trapping virus particles and letting nontarget material to flow through. Viruses are trapped by an array of aligned, nitrogen-doped multiwalled carbon nanotubes, and the size of the array can be controlled-- meaning, scientists can control for the size of the virion they are looking for.
The device has already been put to the test, and has discovered a novel Turkey virus strain and an emerging avian influenza virus strain. The hope, then, is that this new device will help us discover and detect emerging viruses early enough so that viral outbreaks will be a thing of the past.
The Full Paper:
10.1126/sciadv.1601026
A Shortened Review of the Paper:
http://cen.acs.org/articles/94/i40/Nanotube-array-snags-viruses.html
-- Sharon Kam
A bioengineering group led by Si-yang Zheng and Mauricio Terrones has been working to increase our ability for virus surveillance and discovery. The nanotube array is a device that enriches the concentration of virus in field sample at least hundred-fold, by trapping virus particles and letting nontarget material to flow through. Viruses are trapped by an array of aligned, nitrogen-doped multiwalled carbon nanotubes, and the size of the array can be controlled-- meaning, scientists can control for the size of the virion they are looking for.
The device has already been put to the test, and has discovered a novel Turkey virus strain and an emerging avian influenza virus strain. The hope, then, is that this new device will help us discover and detect emerging viruses early enough so that viral outbreaks will be a thing of the past.
The Full Paper:
10.1126/sciadv.1601026
A Shortened Review of the Paper:
http://cen.acs.org/articles/94/i40/Nanotube-array-snags-viruses.html
-- Sharon Kam
Exponential Rise in Chikungunya Cases in New Dehli
Based on a recent article published by The Economic Times on October 3rd, 2016, Dehli has experienced an exponential rise in the number of Chikungunya (a vector borne disease spread via mosquitoes) Cases, a 43% increase in cases over th past week. Approximately 3,700 cases were reported up until September 24th; however, the current count indicates that at least 5.293 people have been diagnosed with Chikungunya. However, fatalities remain low to be approximately 15 cases resulting from Chikungunya related complications.
Many have attempted to identify the cause of such sharp increase in the number of Chikungunya cases. Some researchers have hypothesized a specific mutation in the viral genome; however, the All India Institute of Medical Science (AIIMS) states that the viral genome of the recent Chikungunya cases are identical to the genome of Chikungunya cases in 2006. The Chikungunya Virus also contains only one serotype with three genotypes consisting of Asian, West African, and East Central South African. Some contemplate that the increase could be a recent of increased immigration of people who were not exposed to the virus during the 2006 outbreak.
The reader should recognize the fact that these numbers indicate Chikungunya cases for one CITY, and there are many more people afflicted with the virus in the COUNTRY of India (with a total case count of approximately 19,617 cases).
Check out the article here: http://economictimes.indiatimes.com/news/politics-and-nation/delhi-nearly-5300-chikungunya-cases-43-per-cent-rise-over-last-week/articleshow/54658075.cms
~Michelle Bach (Humans and Viruses 2016-2017)
Many have attempted to identify the cause of such sharp increase in the number of Chikungunya cases. Some researchers have hypothesized a specific mutation in the viral genome; however, the All India Institute of Medical Science (AIIMS) states that the viral genome of the recent Chikungunya cases are identical to the genome of Chikungunya cases in 2006. The Chikungunya Virus also contains only one serotype with three genotypes consisting of Asian, West African, and East Central South African. Some contemplate that the increase could be a recent of increased immigration of people who were not exposed to the virus during the 2006 outbreak.
The reader should recognize the fact that these numbers indicate Chikungunya cases for one CITY, and there are many more people afflicted with the virus in the COUNTRY of India (with a total case count of approximately 19,617 cases).
Check out the article here: http://economictimes.indiatimes.com/news/politics-and-nation/delhi-nearly-5300-chikungunya-cases-43-per-cent-rise-over-last-week/articleshow/54658075.cms
~Michelle Bach (Humans and Viruses 2016-2017)
Culturable human norovirus
At last! What we've all been waiting for... an in vitro culture system for human norovirus.
Even if you've never heard of norovirus, chances are that you've head of its effects. From outbreaks of gastrointestinal illness on cruise ships to Chipotle's foodborne illness issues, norovirus's wrath is far-reaching and serious. For most, a norovirus infection is an undesirable but temporary condition. For the elderly, immunocompromised, and for children, an infection can lead to much more serious complications. In the developing world, about 200,000 deaths per year can be attributed to norovirus infection (Lopman et al. 2016).
Why haven't we done more to learn more about norovirus infection and how to prevent spreading the virus? In part, it's because there haven't been any methods to study the virus in vitro. Scientists have developed genetic assays to detect norovirus in food, water, and other samples, but there hasn't been a way to determine the infectivity of the virus if the genome was detected. Essentially, the virus's DNA can be present in food or water, but that doesn't mean that the virus can infect its host. This has been an issue for anyone trying to determine the risk that norovirus presents in a particular environment... until now. Scientists at Baylor University have reported a cell line that can propagate the virus. If this result is replicable, huge strides can be made in the understanding of human norovirus pathogenesis. Labs may now be able to make stocks of the infectious virus and perform experiments evaluating its infectivity, response to therapeutics, etc.. It may even help with the development of a norovirus vaccine.
Although this result is promising, it's just the beginning for norovirus culturing assays. We still need to replicate these experiments and confirm results. In the mean time, wash your hands and wash your produce thoroughly.
-Katy Graham
Sources:
Lopman BA, Steele D, Kirkwood CD, Parashar UD (2016) The Vast and Varied Global Burden of Norovirus: Prospects for Prevention and Control. PLoS Med 13(4): e1001999. doi:10.1371/journal.pmed.1001999
Even if you've never heard of norovirus, chances are that you've head of its effects. From outbreaks of gastrointestinal illness on cruise ships to Chipotle's foodborne illness issues, norovirus's wrath is far-reaching and serious. For most, a norovirus infection is an undesirable but temporary condition. For the elderly, immunocompromised, and for children, an infection can lead to much more serious complications. In the developing world, about 200,000 deaths per year can be attributed to norovirus infection (Lopman et al. 2016).
Why haven't we done more to learn more about norovirus infection and how to prevent spreading the virus? In part, it's because there haven't been any methods to study the virus in vitro. Scientists have developed genetic assays to detect norovirus in food, water, and other samples, but there hasn't been a way to determine the infectivity of the virus if the genome was detected. Essentially, the virus's DNA can be present in food or water, but that doesn't mean that the virus can infect its host. This has been an issue for anyone trying to determine the risk that norovirus presents in a particular environment... until now. Scientists at Baylor University have reported a cell line that can propagate the virus. If this result is replicable, huge strides can be made in the understanding of human norovirus pathogenesis. Labs may now be able to make stocks of the infectious virus and perform experiments evaluating its infectivity, response to therapeutics, etc.. It may even help with the development of a norovirus vaccine.
Although this result is promising, it's just the beginning for norovirus culturing assays. We still need to replicate these experiments and confirm results. In the mean time, wash your hands and wash your produce thoroughly.
-Katy Graham
Sources:
Lopman BA, Steele D, Kirkwood CD, Parashar UD (2016) The Vast and Varied Global Burden of Norovirus: Prospects for Prevention and Control. PLoS Med 13(4): e1001999. doi:10.1371/journal.pmed.1001999
K. Ettayebi et al., Science
10.1126/science.aaf5211 (2016).
West Nile Virus and Snakes
I always thought that the West Nile virus was a tropical disease
that only affected rugged explorers of the Nile River–I mean it has to be
called the West Nile virus for a reason. This virus has certainty made is presence
known in the US, since as of October 4th 2016 the CDC reported 1,162 cases of West Nile Virus infection. The
virus’s name does offer some historical insight as WNV was first identified in
the West Nile region of Uganda in a woman in 1937. The virus mysteriously made its way to the US
in 1999, and within five years it spread to Canada, the Caribbean, and Central
America. While the virus affects humans, it is also capable of infecting birds.
However, a recent journal has reported that wild snakes can harbor WNV. This study also raised important
questions in the role of snakes in the eco-epidemiology of WNV, while also
reporting that oral swabs of snakes can successfully report WNV
infection.
This study was important as it offered an explanation for why the
WNV outbreak in the northeastern US was unusually severe this year.
According to the study, infected snakes that hibernate over the winter incubate the virus, and then mosquitos bite the snakes and pass the virus to
birds and humans.
Establishing the link between snakes and WNV is good news for
control efforts, since controlling the snake virus reservoir could reduce WNV
human infection rates.
I think a round of applause is in order for the researchers who
did mouth swabs of snakes to help further our understanding of WNV.
A cottonmouth snake, which has been shown to harbor West Nile
Virus (Image credit)
-Cynthia Taylor
Sunday, October 9, 2016
Mayaro Virus Causes Increased Concern Amongst Scientists
There seems to be a virus that
has many scientists are turning their attention to recently—the Mayaro virus.
Mayaro is mosquito-borne virus in the Togaviridae family that was first
identified in 1954 in Trinidad. While it has not caused the same impact and
commotion as say Zika or Ebola have, this relative of the Chikungunya virus is
causing concern due to its similarity to chikungunya and dengue.
While Mayaro has typically
only been found in certain areas around the Amazon, recent diagnoses of an
8-year-old Haitian boy increased the concerns from scientists. The director of
the Emerging Pathogen Institute at U of Florida, Glenn Morris, commented on
how, “We need to recognize that while Zika understandably has all the
attention, it’s not the first virus to move through in epidemic form, nor is it
going to be the last.” Considering how viral diseases such as Ebola and Zika
spiraled throughout different areas in an epidemic manner, scientists believe
that Mayaro has a similar capability to be the new hot topic, which is
something that is obviously undesirable. So far the 8-year-old is the only
known case so the scientists don’t want to jump to conclusions but they believe
that if another case is detected then it can be an alarm for growing concern
within the Caribbean region. With viral epidemics, it is hard to detect the source
before they become, well an epidemic, so these scientists’ concerns are very
much real and may be enough to stop Mayaro from infecting more individuals.
Article Reference:
Japanese Encephalitis in India
The Malkangiri district in India is experiencing a surge of deaths from Japanese encephalitis, a viral infection that can cause brain inflammation. As of October 8th, the death toll had grown to 42, with two children being the most recent victims. Though, while there is a vaccination for Japanese encephalitis, Dr. A.C. Dhariwal, the director of the National Vector Borne Disease Control Programme, is not encouraging vaccination due to the worry that the vaccine could be falsely associated with the acquisition of the disease if it continues to spread. He further emphasized that “We should not be too enthusiast [sic] to protect the community by vaccination during transmission period” as it did not work in two other Indian states, Tripura and Assam (Pradhan).
 |
| Geographic Distribution of Japanese Encephalitis Risk Areas (CDC) |
To add a little more about Japanese encephalitis, it is caused by Japanese encephalitis virus, a flavivirus. It is transmitted to humans via Culex genus mosquitoes, but it “is maintained in a cycle between mosquitoes and vertebrate hosts, primarily pigs and wading birds.” Because of its vector, its transmission is often seasonal and dependent on standing water for the mosquitoes. While less than 1% of those infected get a serious illness, 20-30% of those that get encephalitis will die (“Japanese Encephalitis”).
References:
Pradhan, Ashok. “Japanese encephalitis vaccination may boomerang: Centre.” The Times of India, 8 Oct. 2016. Web.
“Japanese Encephalitis.” Centers for Disease Control and Prevention, 5 August 2015. Web. 9 Oct. 2016.
- Devon Zander
- Devon Zander
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