Poliomyelitis, a disease caused by poliovirus (types A, B, C) of the Picornaviridae virus family, is still endemic to three countries in the world: Afghanistan, Pakistan and Nigeria. Incidence of poliomyelitis has been reduced by 99% since 1988, yet areas of the world with poor sanitation and violent conflict continue to struggle with eradication. Why? - Poliovirus is typically transferred by the faecal-oral route so poor sanitation increases the likelihood that poliovirus will be transmitted from one human to another. Also, conflict prevents healthcare workers from accessing, often vulnerable, populations in order to run vaccination programs.
Of particular concern to public health workers and polio eradication groups are countries experiencing high or rising levels of conflict, either at the local or national level. Violent conflict and a distrust of public health workers has continued to prevent full eradication of poliovirus in Afghanistan and Pakistan. In 2015, Nigeria was declared polio-free, yet this year, Nigeria was added back onto the polio endemic list by WHO due to the appearance of three wildtype poliovirus cases in the northeastern province of Borna. The three cases were discovered in areas that had just recently been cleared of Boko Haram militants. Now, public health workers blame Boko Haram, a group known to advocate against modern medicine, including vaccines, for preventing access to poliovirus vaccines among northern Nigerian populations. Similar concerns have arisen in regards to increasing violence in areas around the world, most notably in Syria. However, polio is no longer endemic in a number of other countries that were experiencing violent conflict during successful eradication (Cambodia, Colombia, the Philippines, Sri Lanka, etc.) meaning that eradication is possible even during intense periods of violence. Past strategies employed to address heightened risk for a polio outbreak include: emergency vaccination of freed populations or ceasefire negotiations for emergency vaccinations and refugee and internally displaced people camp vaccination programs. Find out more about these barriers here.
Carolyn Oliver
Sources:
1. http://polioeradication.org/
2. http://www.humanosphere.org/global-health/2016/09/conflict-zones-pose-final-threat-eradicating-polio/
3. PolioNow Interactive Map: http://polioeradication.org/polio-today/polio-now/
4. https://www.ncbi.nlm.nih.gov/pubmed/10812729
Thursday, October 6, 2016
FluMist is no longer recommended
This year, the American Academy of Pediatrics no longer recommends FluMist, a flu vaccine that is administered as a nasal spray. Each year,
a CDC committee reviews data to determine the effectiveness of FluMist and the
flu shot. Although FluMist has been successful in preventing the flu in the past, for the past
three seasons, FluMist has been ineffective. It is currently not known why
FluMist has been ineffective during the past few seasons.
The American Academy of Pediatrics
continues to recommend flu vaccines for anyone six months and older. As the
only needle-free flu vaccine, FluMist is favored by some parents. However,
doctors are not concerned about a decline in vaccination rates. So far, these
parents have simply had their children vaccinated via the flu shot instead. After
all, children can be cajoled into getting the shot and no one likes getting the
flu.
Furthermore, Dr. David Henderson, an OhioHealth pediatrician, believes that the 2009 swine flu epidemic, which resulted in many hospitalizations and even some deaths, has encouraged people to receive the flu shot.
In addition, the new flu vaccine guidelines affect a relatively small
percentage of patients, since the FluMist accounts for just a third of flu
vaccines given to children.
Article:
Scutti S. Pediatricians update flu vaccine guidelines to remove FluMist. CNN. 2016 Sep 6.
Other reference:
Grohskopf LA, Sokolow LZ, Broder KR, et al. Prevention and Control of Seasonal Influenza with Vaccines. MMWR Recomm Rep 2016;65(No. RR-5):1–54. DOI: http://dx.doi.org/10.15585/mmwr.rr6505a1.
Grohskopf LA, Sokolow LZ, Broder KR, et al. Prevention and Control of Seasonal Influenza with Vaccines. MMWR Recomm Rep 2016;65(No. RR-5):1–54. DOI: http://dx.doi.org/10.15585/mmwr.rr6505a1.
-Sally Tran
Wednesday, October 5, 2016
Zika Vaccine Economically Viable
In a recent article released by NBC News on October 4th, 2016, pharmaceutical companies have deemed the Zika vaccine to be an economically viable investment due to the vaccine's public health implications, especially for residents of the United States and Europe who are willing to pay higher prices for such vaccine. Because Zika is the only sexually transmitted mosquito borne illness, public health officials state that the fear towards the disease is much higher than presented although the disease itself may often times be asymptomatic or mildly symptomatic. A vaccine is predicted to be released in two years.
Though two years may be enough time for the Zika virus to subside in Latin American nations, many people in Latin America would be willing to receive the vaccine as a preventative measure, were the disease to re-emerge in the future. Those who travel often (business executives, diplomats, etc.) will be highly encouraged to receive the vaccine before traveling to areas infected with the virus. Joseph Kim, the chief executive of Inovio Pharmaceuticals, states that Zika-related markets may reach a level of more than $1 billion. Certain pharmaceutical companies envision the Zika vaccine to be similar to Gardasil in that the vaccine is administered to boys and girls before puberty.
The National Institutes of Health is also involved in vaccine production for a wide variety of infectious disease, Zika being one of them. The NIH had invested in a West Nile Virus vaccine, but the vaccine was not as popular due to the lack of alarm towards the disease. The NIH is currently investing in the Zika virus by launching their own project while also supporting pharmaceutical companies; however, the NIH has yet to invest solely to one pharmaceutical industry until efficacious results are presented.
Some pharmaceutical industries that are currently working on the Zika vaccine include Protein Sciences Corp, Sanofi in France, GSK, and Takeda in Japan.
Check out the article here: http://www.nbcnews.com/storyline/zika-virus-outbreak/zika-vaccine-could-actually-be-profitable-companies-say-n659276
~Michelle Bach (Humans and Viruses 2016-2017)
Though two years may be enough time for the Zika virus to subside in Latin American nations, many people in Latin America would be willing to receive the vaccine as a preventative measure, were the disease to re-emerge in the future. Those who travel often (business executives, diplomats, etc.) will be highly encouraged to receive the vaccine before traveling to areas infected with the virus. Joseph Kim, the chief executive of Inovio Pharmaceuticals, states that Zika-related markets may reach a level of more than $1 billion. Certain pharmaceutical companies envision the Zika vaccine to be similar to Gardasil in that the vaccine is administered to boys and girls before puberty.
The National Institutes of Health is also involved in vaccine production for a wide variety of infectious disease, Zika being one of them. The NIH had invested in a West Nile Virus vaccine, but the vaccine was not as popular due to the lack of alarm towards the disease. The NIH is currently investing in the Zika virus by launching their own project while also supporting pharmaceutical companies; however, the NIH has yet to invest solely to one pharmaceutical industry until efficacious results are presented.
Some pharmaceutical industries that are currently working on the Zika vaccine include Protein Sciences Corp, Sanofi in France, GSK, and Takeda in Japan.
Check out the article here: http://www.nbcnews.com/storyline/zika-virus-outbreak/zika-vaccine-could-actually-be-profitable-companies-say-n659276
~Michelle Bach (Humans and Viruses 2016-2017)
Shigellosis Outbreak in Flint, Michigan
Flint, Michigan is still in the midst of a water
crisis that started back in 2014 when Flint official sought a cheaper water
supplier. The change is water supply eventually led to a decline in water
quality and eventually it was found that lead levels were at a hazardous
amount. This crisis led to an increased lead level found amongst the Flint
children and has since caused a lot of distrust with the water of Flint, which
may have spurred this new outbreak.
This year there have been 53 cases of Shigellosis
within Flint. Considering that 53 of the 84 cases found within the entire
county were found in Flint alone leads many to turn toward the health quality
as a possible explanation. Shigellosis, according to the CDC, is an infectious
disease that causes those infected to “develop diarrhea, fever, and stomach
cramps.” The bacteria Shigella will resolve in 5-7 days and its stop can be
through frequent and careful handwashing. The problem in Flint, however, is
that the fear of using the water supply has led to a decrease hygiene measures,
such as washing hands and bathing. The county environmental health supervisor,
Jim Henry, said that the residents of Flint are more and more relying on baby
wipes as a form of cleaning their children and hand, but that method fails to
properly kill bacteria and should not be an alternative to handwashing.
While Shigella is a bacteria rather than a
virus, it is another form of an infectious disease outbreak and highlights the
importance of preventative measures, such as handwashing, to stop the spread of
the pathogen. While Shigellosis is not as death threatening as Ebola, measures
should still be quickly take to prevent further outbreaks.
Sources: https://www.cdc.gov/shigella/
--Jeanette Rios
Saturday, June 6, 2015
Contagiousness of MERS
The recent outbreak of MERS - Middle East respiratory syndrome virus - has infected at least 36 people in South Korea. As a result, the outbreak has been a source of concern for epidemiologists around the world. Efforts to quarantine people and camels have followed in an attempt to squash the outbreak.
Perhaps surprisingly, however, the MERS virus is not highly contagious; previous studies have found that its R0 is 2-3, meaning that the average infected person only infects two to three other people. In fact, MERS is thought to be spread primarily zoonotically (from camels to humans).
It is important to note that while the MERS virus is not highly contagious, it is still important to monitor the outbreak and prevent it from growing any larger. One issue commonly found in reports on the contagiousness of viruses is that there is an implication that less contagious viruses cannot manifest into epidemics and that they are less serious than highly contagious viruses. However, with HIV - a virus that is relatively low in contagion (e.g. exposure to the virus via an infected needlestick seldom leads to infection) - we see that it can still lead to a deadly epidemic. More recently, Ebola, a virus with an R0 if 1.5-2.5 manifested itself into the huge Ebola outbreak in West Africa.
Thus, articles reporting on the contagiousness of viruses should be taken just as a presentation of the facts, or as one of many indicators of the epidemic potential of a virus.
Source: http://abcnews.go.com/Health/infectious-mers-virus-compared-viruses/story?id=31535945
--Andrew Duong
Perhaps surprisingly, however, the MERS virus is not highly contagious; previous studies have found that its R0 is 2-3, meaning that the average infected person only infects two to three other people. In fact, MERS is thought to be spread primarily zoonotically (from camels to humans).
It is important to note that while the MERS virus is not highly contagious, it is still important to monitor the outbreak and prevent it from growing any larger. One issue commonly found in reports on the contagiousness of viruses is that there is an implication that less contagious viruses cannot manifest into epidemics and that they are less serious than highly contagious viruses. However, with HIV - a virus that is relatively low in contagion (e.g. exposure to the virus via an infected needlestick seldom leads to infection) - we see that it can still lead to a deadly epidemic. More recently, Ebola, a virus with an R0 if 1.5-2.5 manifested itself into the huge Ebola outbreak in West Africa.
Thus, articles reporting on the contagiousness of viruses should be taken just as a presentation of the facts, or as one of many indicators of the epidemic potential of a virus.
Source: http://abcnews.go.com/Health/infectious-mers-virus-compared-viruses/story?id=31535945
--Andrew Duong
Thursday, June 4, 2015
Inexpensive Blood Test Reveals Your Viral Exposure History?
A international team of scientists has just developed a
comprehensive screening mechanism called VirScan. This technology is a
high-throughput method that comprehensively analyzes antiviral antibodies using
immunoprecipittion and parallel DNA sequencing of a bacteriophage library that
displays proteome-wide peptides from all known human viruses. While it might
not be a complete history, VirScan revealed the presence of antibodies to 10 or
more different viral species per person in a 569-person study that included
subjects from the United States, Peru, Thailand, and South Africa. At least two
of the individuals tested had at least antibodies against 84 different viral
species. The study found 206 different viral species in total, and over 1000
strains.
Widespread adoption
of VirScan could be a great diagnostic and research tool. Current serological
testing is usually focused on testing for one pathogen at a time. The analysis
costs about $25 per person and only 1 microliter of blood. One of the
unexpected results of VirScan was that different people produced structurally
similar antibodies to a small number of “public” epitopes for many different
viral species. The team hopes that VirScan can be used to study the effect of
host-virome interactions on human health, and possibly be expanded for test for
bacterial, fungal, and protozoan pathogens.
Clinically,
VirScan could be used to identify antibodies for a virus that a patient might
not be aware he/she was exposed to, especially latent viruses that can lead to
cancer (e.g. hepatitis C). VirScan could also be used to draw associations
between viruses and chronic conditions such as diabetes and chronic fatigue
syndrome.
Other Sources:
http://news.sciencemag.org/biology/2015/06/new-test-could-reveal-every-virus-thats-ever-infected-you
--Joe
Wednesday, June 3, 2015
A New Way to Look at Viruses—Weighing by Mass Spectrometry
There are
various techniques that have been used over the years to study viruses.
Scientists have studied their pathological effects in living systems, their
cytopathic effects in cell culture. We can directly observe viruses through
x-ray crystallography.
Pathological Approach:
Cytopathic Effect:
Characteristic deformities that certain viruses cause to the
cells they infect. For example, some herpes viruses cause multinucleation.
Respiratory syncytia virus (Paramyxoviridae) causes syncytia (fusion of
multiple cells into one large one).
--multinucleation (wikimedia commons)
X-Ray Crystallography:
Was used to produce the first pictures of DNA--it involves studying the diffractions of x-rays from crystalline atoms.
--X-ray crystallography of Poliovirus type 1
Scanning Electron Microscopy:
Scanning electron microscopes produce 3-dimensional images.
They can show topographical details of a virus.
HSV-1 SEM, http://coldsoreshomeremedies.ca/index.php/2009/02/what-is-a-cold-sore/
Transmission Electron Microscopy:
TEM has a higher magnification and greater resolution, but
produces 2-dimensional rather than 3-dimensional images.
However, there has just been a study to use a different
imaging technique to study viruses: mass spectrometry. For the first time ever,
we can weigh an intact virus. Specifically, the study used heavy-ion mass
spectrometry MS to study a mixture of intact virus particles. The team, led by Carnegie
Mellon University’s Mark Bier and his graduate student Logan Plath, used
samples containing two varieties of a cowpea (black-eyed pea) mosaic virus (a
plant virus); they found that one virus weighted 5.65 megadaltons, and the
other 4.84 megadaltons. Both of these numbers were approximately that of the
theorized masses of the viruses.
Previously, mass spectrometry’s use in virology has been
limited because intact viruses have been too large. To get around this problem,
Bier’s group used a cryodetector-based matrix-assisted laser
desorption/ionization time of flight mass spectrometer (that’s a real mouthful),
called a Macromizer. The 3.75 meter-long apparatus can analyze low charge heavy
ions with greater sensitivity than standard mass spectrometers.
--black-eyed pea mosaic virus--what's it gonna do with all those megadaltons inside that trunk?
http://phys.org/news/2015-06-chemists-intact-virus-mixture-mass.html
http://www.sciencedirect.com/science/article/pii/S0166093414004443
--Joe
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