IPB University Lecturer: Stay Alert with the New Type of Swine Flu, G4 EA H1N1

IPB University lecturer from the Department of Animal Disease and Veterinary Public Health, Faculty of Veterinary Medicine, Dr. Surachmi Setiyaningsih invites us to recall a decade ago, precisely in 2009, when the world was shaken by the emergence of a new flu virus that causes human respiratory disease. First reported in Mexico and the United States, the disease is contagious to people who come in contact with infected pigs.

But the subsequent spread was accelerated through human-to-human transmission, and as a result the disease spread to all continents. This prompted the world health agency, WHO to declare a swine flu pandemic in June 2009 and the cause of the virus known as pdm / 09 H1N1. The virus then settled and circulated among seasonal flu viruses, so WHO decided to end the pandemic status in August 2010.

Related to the discovery of a new swine flu virus in China which was widely reported by various global media at the end of June 2020, Dr. Surachmi said that the virus was a new variation of influenza virus. If pdm / 09 H1N1 is a cross between triple reassortant (TR) H1N1 and Eurasian avian-like (EA) H1N1, then the virus that appears in China is a mixture of EA H1N1, pdm / 09 H1N1 and TR H1N1.

The virus, named Genotype 4 (G4) EA H1N1, is suspected to be circulating for the first time in the pig population in China since 2016 with increasing dominance from year to year. The finding was made possible because China has a comprehensive and systematic influenza virus surveillance program.

When asked about the link between this new swine flu virus and the high number of swine deaths in Sumatra, Dr. Surachmi said that deaths in pigs that have spread in Sumatra and other parts of Indonesia since late 2019 were caused by infection with the African swine feveri (ASF) virus and / or Classical swine virus fever (CSF). Possibly because of the word "fever", it caused various media to refer to it as "swine flu" in its reporting.

ASF and CSF disease only attacks pigs and is deadly, but is not transmitted to humans. While influenza virus infections in pigs generally show mild to moderate respiratory symptoms and are rarely lethal, but can be transmitted to humans.

Regarding the danger of G4 EA H1N1 infection in humans when compared with COVID-19 infection, Dr. Surachmi cited evidence of the danger of G4 EA H1N1 infection in humans is still very little to be able to assess the virulence of the virus. Articles reporting viral infections in pig farm workers in China prove that about 10 percent (35 people) are exposed, but there is no clear information regarding the clinical symptoms of these workers. Likewise, the ferocity of the virus in humans is still not proven firmly.

A retrospective study in China found only two patients who were positive for G4 EA H1N1. Which were, one adult (age 46 years) showed symptoms of severe flu accompanied by pneumonia that led to death due to system failure and a case in a 9-year-old child showed only mild flu symptoms.

"The virus that causes COVID-19 (SARS-CoV-2) is easily transmitted between humans. But so far there has been no evidence of human G4 EA H1N1 transmission. As we know, SARS-CoV-2 which also first appeared in China has now spread throughout the world and holds a pandemic status, while circulation of the influenza G4 EA H1N1 influenza virus is still limited in China. However, there is concern that G4 EA H1N1 could potentially become a pandemic considering that the virus is a descendant of the swine flu virus that caused the 2009 pandemic, “ she added.

She further explained that the prediction was based on the findings of a group of Chinese scientists through laboratory experiments using animal models that showed the virus was able to infect and transmit through the air efficiently, very close to the pdm / 09 H1N1 character. In addition, genetic mixing in G4 EA H1N1 results in low antigenic variation and cross-reactivity with seasonal influenza vaccine viruses, so it is feared that the immunity of the existing population is unable to provide protection.

In addition, the ability of G4 EA H1N1 to infect humans will increase opportunities for viruses to adapt further. Therefore, WHO will continue to closely monitor the progress of this case, while emphasizing the importance of our vigilance against influenza, she continued.

In Indonesia, Dr Surachmi observed that the location of the pig pen near to the settlement is still commonly found, especially on people's farms. This increases the risk of transmission to humans as well as being an opportunity for mixing (reassorting) the genes of various strains of influenza viruses that can produce new variants. The importance of applying good biosecurity to pig farms is stressed. Among them maintaining the cleanliness of the cage and the environment by doing sanitation and disinfection, protecting themselves when in direct contact with pigs, and conducting surveillance of pig traffic. Not only that, it is also important to conduct socialization about "swine flu" to the general public and related business actors.

Considering the above, according to her, public health measures related to COVID-19, such as hand hygiene, good breathing ethics, wearing a mask, plus protecting yourself when in contact with pigs are important actions that can be taken to prevent viral infections respiration that can be transmitted through air or direct contact.

"In general, basic research on pathogenic microbial biology that causes animal and human diseases is still relatively small in Indonesia. While early detection is important to do for mitigation. There is no research related to the character of the swine influenza virus at IPB University, generally it is still limited to avian influenza or avian influenza in various avian species. Explorative virological studies on the presence of influenza viruses circulating in areas with high pig density are very important. Given the role of pigs as a vehicle for mixing (mixing vessel) that raises strains or new variants of influenza virus, " she concluded. (IAAS/ELS)

Published Date : 07-Jul-2020

Resource Person : Dr drh Surachmi Setiyaningsih

Keyword : SwineFlu, COVID-19, Pandemic, FKH IPB University, IPB Lecturer