New Swine Flu – G4 EA H1N1 – What to know? Facts around G4 EA H1N1

The fear and caution about new diseases are due to the impact of pandemic H1N1 and COVID-19, bringing everyone to high alert. As a result, the new swine flu news, made everyone to know about G4 EA H1N1. Here we can see many questions related to G4 EA H1N1 and the answers from the standard experimental conclusions published in the journal PNAS titled "Prevalent Eurasian avian-like H1N1 swine influenza virus with 2009 pandemic viral genes facilitating human infection".

What is new swine flu (G4 EA H1N1)?
Is G4 EA H1N1 a newly found virus in 2020?
What is the origin of new swine flu or G4 EA H1N1?
Did G4 EA H1N1 turn into a pandemic?
What is the source of spreading or transmitting this G4 EA H1N1?
What kind of test is available to detect new swine flu or G4 EA H1N1?
Does G4 EA H1N1 transmit human to human?
Clinical symptoms of the G4 EA H1N1 virus in humans?
Impact of G4 EA H1N1 in humans and severity?
What is the Genetic diversity of G4 EA H1N1?
Who are all affected by the G4 EA H1N1 or new swine flu?
Does swine flu vaccine help for the G4 EA H1N1 virus?
What kind of initiative is taken to control G4 EA H1N1?
Any possibilities of G4 EA H1N1 virus to become a pandemic?

What is new swine flu (G4 EA H1N1)?

Genotype 4 (G4) reassortant Eurasian avian-like (EA) H1N1 virus is simply tagged as 'G4 EA H1N1'. 

It is a hybrid virus-transformed from the fusion of different types of lineages. I used the word 'hybrid' to describe the G4 EA H1N1 virus. You know why? 

G4 EA H1N1 is a combination of different lineages and a mixture of humans and mammals. The lineages are classical swine flu lineage, North American triple-reassortant lineage, and Eurasian avian reassortant genotype 4.

Is G4 EA H1N1 a newly found virus in 2020?

No, it is not a new one. First, in 2001 Eurasian avian-like H1N1 was identified. Gradually, it becomes a huge pandemic spread in humans (2009) as H1N1. Later, China has initiated intense surveillance of swine influenza virus from 2011-2018. As a result, scientists have found six genotypes (G1-G6) based on the lineage classification in Eurasian avian H1N1.

"It's important, I think, to reassure people that this is not a new virus - this is a virus that is under surveillance," – Dr. Michael Ryan, Executive Director of the WHO Health Emergencies Program

What is the origin of new swine flu or G4 EA H1N1?

Pigs have H1N1 virus and North American triple-reassortant genes already. Along with these genes, the combination of Eurasian avian reassortant genotype 4 shows high infectivity and transmissibility. 

In 2013, the genotype 4 Eurasian avian H1N1 viruses emerged in southern China. Firstly, Eurasian avian reassortant genotype 4 were found in pigs. Later, the swine workers and some general population were identified with G4 EA H1N1 infections.

Did G4 EA H1N1 turn into a pandemic?

No, at present, there is no clear picture of a pandemic situation like coronavirus (COVID-19); however, scientists and WHO are seriously keeping track of the deadly virus pathways.

What is the source of spreading or transmitting this G4 EA H1N1?

Studies demonstrated that G4 EA H1N1 spread from pigs. The study model using ferret showed that G4 EA H1N1 could infect and transmit to others. Finally, the researchers concluded that G4 EA H1N1 could transmit through aerosols.

The first case was observed from swine workers who are closely related to swine. However, some cases were observed from the general population who do not have any direct contact or relation with swine or swine workers.

What kind of test is available to detect new swine flu or G4 EA H1N1?

The serological test is the only one method existing now for the detection of G4 EA H1N1. However, virologists started working to develop handy tools for the detection of new swine flu.

The existing general influenza virus detection test kits cannot identify the specific emerged strain 'G4 EA H1N1'. Hence, it is essential to customize this particular strain in the future as a preventive measure.

Does G4 EA H1N1 transmit human to human?

In general, Ferrets have been used as an experimental model to study the infection and transmission rate of the virus in humans. The virus transmission experiments in ferrets via direct contact and respiratory aerosol droplet showed that the G4 EA H1N1 virus efficiently transmitted to all other ferrets.

The G4 EA H1N1 virus binds to the human-like SAα2,6Gal receptor and replicates efficiently in human airway epithelial cells.

The studies revealed that G4 EA H1N1 viruses are highly transmissible through direct contact and respiratory aerosol droplets and suggested, G4 EA H1N1 virus can transmit human to human.

Clinical symptoms of the G4 EA H1N1 virus in humans?

The clinical symptoms are pyrexia, sneezing, wheezing, coughing, and weight loss. This is observed in the experimental model, ferrets.

This G4 virus infects the lungs (severe lesions) with hemorrhage, edema (peri bronchiolitis and bronchopneumonia).

Impact of G4 EA H1N1 in humans and severity?

The studies predicted that the impact of the G4 EA H1N1 virus could lead to severe infection and even death.

What is the Genetic diversity of G4 EA H1N1?

This hybrid virus has significant genes from the combination of three new lineages, namely, the ribonucleoprotein (vRNP) genes from the H1N1 lineage and matrix (M) gene from the EA H1N1 lineage, and nonstructural (NS) gene from TR lineage.

Who are all affected by the G4 EA H1N1 or new swine flu?

The young adult swine workers are prone to G4 EA H1N1 virus infection from pigs. As well as possible to transmit human to human.

However, there were cases, including children under 3-year-old reported in 2016 and 2019. More studies are required to predict the scenario accurately.

Does swine flu vaccine help for the G4 EA H1N1 virus?

"G4 EA H1N1 Viruses Exhibit Low Antigenic Cross-Reactivity with Human Influenza Vaccine Strains" – Sun et al. PNAS

The emergent G4 reassortant E4 H1N1 viruses are antigenically different from the current human influenza virus. Hence, the existing immunity developed from the present human seasonal influenza vaccines could not help to protect from G4 EA H1N1.

What kind of initiative is taken to control G4 EA H1N1?

The Eurasian avian-like H1N1 swine influenza virus has "been under surveillance by Chinese authorities and by the global influenza surveillance network around the world, and the WHO collaborating centers," – Dr. Michael Ryan, Executive Director of the WHO Health Emergencies Program

"China has been paying close attention to its development and will take all needed action to prevent its spread and any outbreaks." – Zhao Lijian, Chinese Foreign Ministry Spokesman

Any possibilities of G4 EA H1N1 virus to become a pandemic?

Yes, the new swine flu or G4 EA H1N1 has all the possibilities to boom as pandemic viruses.

"G4 EA H1N1 viruses possess all the essential hallmarks of being highly adapted to infect humans" – Sun et al. PNAS

The way we respond to the handling the G4 EA H1N1 viruses in pigs and close monitoring of swine neighbors will decide the phase transformation.

However, the strong surveillance and close association of scientific communities, as mentioned by the WHO and Chinese authorities, we can believe that the G4 EA H1N1 virus is under control.