Avian Influenza Strain (H5N8) May Now Spread to Humans? Breaking News from Russia.

H5N8 is an Influenza A virus (1). Influenza A viruses are highly pathogenic (2) which means they can cause high mortality and severe disease in poultry. This particular lineage (H5N8) has been found in nations across the world including (but not limited to): China, Germany, Japan, Italy, South Korea, the UK, and occasionally Canada and the U.S. (2).

When the H5N8 strand was examined by the Centers for Disease Control in 2014, it was determined to have a low-intermediate risk of being able to spread to humans from poultry and a low-intermediate risk to significantly impact public health (if it managed to be able to spread among people). At the time, there were no documented cases of the H5N8 Influenza A virus spreading to humans.

On October 31st, 2017, Russian scientists confirmed the possibility of an asymptomatic H5N8 human infection (1). The good news its that a  Russian government ministry on human well-being (Rospotrebnadzor) assured that they examined people who were in close contact with the infected birds, and these individuals had antibodies to the virus in their blood sera.

Nevertheless, the virus has never spread worldwide, and based on the information we collectively have on Influenza A strains, there may be minimal immunity.

Preventive measures against infection include avoiding exposure to infected birds, thorough handw washing, and good hygiene practices (1). For people who work with poultry, annual vaccinations, hand washing, and the use of personal protective equipment is highly recommended to prevent infection (4).

-EM

References:
1. http://www.promedmail.org/
2. http://www.who.int/influenza/human_animal_interface/avian_influenza/riskassessment_AH5N8_201611/en/
3. https://www.cdc.gov/flu/avianflu/influenza-a-virus-subtypes.htm
4. https://www.cdc.gov/flu/avianflu/prevention.htm

Enterovirus D68 in Argentina

The documented history of non-polio enteroviruses in the Americas has been rather persistent (the most famous enterovirus is definitely polio, but there's a whole genus of others!, grand right??); in the U.S. alone, they cause anywhere from 10 to 15 million infections ranging from asymptomatic to mild colds to more serious complications in immunocompromised patients. Enterovirus D68 specifically has had a sporadic presence; first identified in California in 1962, it has mostly only had a small presence in the U.S. with a abnormal spike in infections in 2014. A respiratory illness, this virus resides in mucus, saliva, and sputum, which explains its spread through coughs and sneezes.

Though it has not been widely documented in the U.S. since its 2014 outbreak, it has found it's way to other continents. Specifically, it caused a uproar in several European countries that recorded clusters of infections in 2016. Fast forward to 2017 and one finds that is has travelled to Sudamerica, taking up residence in Argentina. The equivalent of the Argentinian CDC discovered multiple cases of acute flaccid myelitis (AFM), a neurological disorder characterized by numb limbs with an otherwise idiopathic origin. AFM has previously been linked to D68, so this presentation of symptoms can be used to retroactively trace/identify D68 infection. These Argentinian infections appear only in children under the age of 15 (mostly identified in nasal aspirate but also observed in CSF of some, indicating its neuroinvasive capacity). The presence of this virus (and the related Enteroviruses B and C) emphasizes how little is known about the neuroinvasiveness of enteroviruses and their contribution to disease. Maybe events such as this will encourage future research!

Entero, hasta luego :) ;)

Javarcia Ivory

Yellow fever in Semen (make-up post for 10/16)

Yellow fever is one of the most historically relevant and influential virus of the past three to four centuries. A Flavivirus, it's famously transmitted by arthropods (google the Panama Canal), and its colored name and peppered past comes from its inducement of jaundice. Given these methods of transmission and clinical presentation, it's most common location for identification is blood. However, a recent publication has brought that into surprising question.
In Sao Paulo Brazil, a convalescent patient, who had recently travelled to another area of the country, was infected with Yellow fever, presenting the typical signs of fever, chills, myalgia, and nausea. Physicians originally tested for the related dengue (also flavivirus) and found no trace, but his symptoms worsened; so then they obtained more serum in addition to urine samples, deciding to test them for YFV (yellow fever virus). Here's the kicker: the serum originally tested negative with qRT-PCR;using the prior assay and a IgM-antigen capture ELISA, tested urine(!!!!) returned positive results. Specifically, it tested phylogenetically positive for the South American I strain cluster of these viruses. Other samples of these strain were obtained in a bordering area of Brazil to which our patient travelled (Minas Gerais).
The major changes in this viral samples genome were in NS5, the RdRp gene. These types of changes have previously been associated with alterations to viral replication, immune reactions, and protein interactions. These results, according to the paper authors, suggest that semen and urine may be new sources of samples to test for YFV.

I'll yellow feva, see-ya later! :) ;)

Javarcia Ivory

Reference: Date: January 2018 [ahead of print]
Source: Emerging Infectious Diseases 24 (1) [edited]
<https://wwwnc.cdc.gov/eid/article/24/1/17-1310_article>


Carla M. Barbosa, Nicholas Di Paola, Marielton P. Cunha, Manica J.
Rodrigues-Jesus, Danielle B. Araujo, et al. Yellow Fever Virus in
Urine and Semen of Convalescent Patient, Brazil.

"Coffee with Polio Experts"

I admittedly don't listen to podcasts, BUT I would consider it to learn something about viruses. The Global Polio Eradication Initiative is a collective of health professionals who aim to eliminate polio in the world. Since the initiation of their eradication campaign in the 1980's, the incidence of paralysis from polio in children has dropped from 1.000 cases per day to 100 per year. Pakistan, Afghanistan, and Nigeria are the last countries battling polio, so the initiative focuses its vaccination drives there. They also publish short, informational videos that discuss their efforts through the experiences of their "field commanders" on the front lines. One video features a Dr. Naveed Sadozai who recalls an instance when he had to convince sheepherders to let him vaccinate his family. This is just one of many issues faced by these "field commanders," give them a listen! (Sources: here and here)

-Andrew

Egg-Based Flu Vaccines May be Less Effective: The Case of the H3N2 Vaccine

How are egg-based vaccines made?
Egg-based vaccines are made by injecting a virus into a fertilized, hen egg. The virus then continues to replicate in the egg as it is incubated, and then the virus is either killed ("inactivated") or weakened (attenuated). Inactivated viruses are more commonly used for flu shots, while nasal sprays commonly contain attenuated viruses (1).

Why are egg-based vaccines making headlines?
According to a study published on October 23rd, by researchers Wu, Zost, Thompson, Oyen, Nycholat, McBride, Paulson, Hensley,  and Wilson, egg-based vaccines appear to be getting less effective over time (2), and these observations may be possibly explained by the mutations that occur in the virus during the process of making egg-based vaccines (2). These mutations affect the structure of the virus, specifically receptor binding sites which are usually recognized by the immune system  and are critical for the immune system to recognize in order to build immunity(2). 

Wu et. al are recommending that manufacturers change their vaccine production method to a method in which the virus is less prone to mutations in these critical structures. An alternative method of vaccine production that has been proposed is cell-based flu vaccine production. The advantage to this method is that the virus can replicate more quickly, cells can be "frozen" and stored for later use, and the virus may be less likely to develop mutations which decrease its effectiveness (and which may be a product of the virus adapting to its egg host (4).

-EM

References:
1. https://www.cdc.gov/flu/protect/vaccine/how-fluvaccine-made.htm
2. http://journals.plos.org/plospathogens/article?id=10.1371/journal.ppat.1006682
3. http://www.contagionlive.com/news/egg-based-flu-vaccines-offer-lower-levels-of-protection-against-certain-virus-subtypes
4. https://www.cdc.gov/flu/protect/vaccine/cell-based.htm

New dengue virus confirmed in India

In India, researchers already knew that there were dengue virus that was prevalent, which are the strains of dengue virus (DENV) types 1-4. However, researchers had not found the Asian genotype of DENV-1 before in India. The other genotype of DENV-1 that was already existing in India prior to finding out about the Asian genotype is called the American-African genotype of DENV-1.

The Asian genotype of DENV-1 had already been circulating in other parts of the world, as there was an outbreak of it in Singapore in 2005. In addition, it is important to acknowledge that scientists finding this specific genotype of DENV-1 does not mean this genotype is more widespread in India. However, historically, DENV-1 has been much more widespread than the other strains, so it is concerning to find the presence of a new genotype of that strain.

It is important to collect many more samples before ever coming to a conclusion like that. The ratio between the Asian genotype and American-African genotype of DENV-1 is going to be closely looked at for the next couple of years to potentially prevent any future outbreaks in the nation of India.  

Eyasu Kebede

Source: https://timesofindia.indiatimes.com/home/science/new-dengue-virus-confirmed-in-india/articleshow/61377991.cms

http://www.sciencedirect.com/science/article/pii/S0042682217302155

In a First, Gene Therapy Halts a Fatal Brain Disease

A study in the New England Journal of Medicine has found that a new form of genetic therapy may help slow down the neurodegenerative effects of a disease called adrenoleukodystrophy (ALD). Researchers decided to use a “disabled form” of the HIV virus for proceeding with the treatment plan, which was considered quite risky at the time.

The plan of action consisted of the following: First, take a sample of bone marrow stem cells from a patient with a gene mutation heavily correlated with the ALD disease. Then, put in a desired gene in the bone marrow stem cells and put them back in the patient. The hope would be that the stem cells would enter the brain and become glial cells in order to stop further degeneration in the brain. The preferred timeline for all of this to occur was in about a year or so after putting the stem cells with the new genes back into the patient. The study showed that 15 out of the 17 participants no longer showed any symptoms after this form of treatment. This study is important because it shows promising outcomes to this type of therapy for perhaps other neurodegenerative diseases. I am excited as to what the future has to offer.

- Eyasu Kebede


Source:  https://www.nytimes.com/2017/10/05/health/gene-therapy-brain-disease.html