Tag: World Health Organization

An Overview of Swine Flu

Swine flu or influenza is a condition caused by strains of subtypes of Influenza A virus called H1N1, H1N2, H3N1, H3N2, and H3N3. These viruses are common in pigs located in midwestern United States, Canada, South America, Mexico, Mainland China, Japan, Taiwan, Europe, and other Eastern Asian countries.

Transmission of influenza virus from swine to humans is relatively uncommon and does not always result to human influenza but often leads to production of antibodies in the blood. When properly cooked, pig meat does not have the potential of passing the virus. Transmission that leads to human influenza is called zoonotic swine flu.

People who work with pigs, particularly those with direct exposure, are at greater risk of being infected with swine flu. Towards the middle of the 20th century, identification of influenza subtypes became likely paving the way for an accurate diagnosis of transmission to humans. Since then, 50 infections have been confirmed and recorded.

It is rare for these strains of swine flu to be transmitted from one human to another. In humans, the symptoms of swine flu are similar to common influenza as well as influenza-like illness such as chills, sore throat, fever, coughing, muscular pains, severe headache, and general discomfort.
The 2009 swine flu outbreak in humans was caused by a new strain of influenza A virus subtype H1N1 which have genes that closely resemble swine influenza. The root of this new strain is not known. According to the World Health Organization for Animal Health, this new strain has not been isolated in pigs. It is capable of human-to-human transmission and manifests the normal symptoms of influenza.

Swine can be infected with human influenza such as the case of the 1918 flu pandemic and the 2009 flu outbreak. Swine flu was first proposed as a disease associated with humans during the 1918 flu pandemic. During that time, pigs became simultaneously sick with humans.

Influenza virus as a cause of disease in pigs was first identified in 1930. For the next six decades, strains of swine influenza became almost exclusively H1N1. From 1997 to 2002, new strains of three varied subtypes and 5 different genotypes were identified as the cause of influenza among pigs in North America.

From 1997-1998, H3N2 strains developed. They included genes acquired through reassortment of human, avian, and swine viruses and have been a principal cause of wine influenza in North America. Reassortment between H1N1 and H3N2 resulted to the development of H1N2. In Canada, a strain of H4N6 resulted from the reassortment of avian and swine flu but was isolated on a single farm.

The H1N1 variant of swine flu is one of the descendants of the strain that brought about the 1918 flu pandemic. While persisting in pigs, the descendants of the 1918 virus have also been transmitted throughout the 20th century which resulted to the usual seasonal influenza outbreaks.
It is interesting to note that direct infection from pigs to humans is rare, with only 12 confirmed cases in the United States since 2005.

However, since the influenza strains remain in the pigs after they have disappeared in the human population can make these pigs a reservoir where the influenza virus could survive and later on transmitted to humans as soon as their immunity to the strain is no longe effective.

Swine flu has been recorded as zoonosis in humans several times, oftentimes with limited distribution and rarely with massive distribution. Swine outbreaks are common and can lead to significant economic losses in the industry, mainly leading to stunting and expanded market time. Swine influneza, for instance, the British meat industry has experienced 65 million of losses annually.

Vaccinations of Swine Flu

Vaccine against seasonal influenza strain H1N1 is not believed to protect us. Vaccines against the Swine Flu to cope with seasonal flu to minimize infection rates are typically developed, and yet annually it still kills around half a million of the worlds population. Today, they use an injection of “killed virus”, the worlds flu vaccines. Manufacturers are asked to produce a vaccine for H1N1, they are unlikely to be able to respond quickly enough if a global pandemic is declared.

About a billion doses of any one vaccine each year is the only they can produce, so that even if all the capacity was switched to fight a pandemic flu, as opposed to a seasonal flu. Few years ago, the supply of the vaccines they have produced were enough to epidemic but now is not enough for the total populations outbreak.

Deadlier wave of a new H1N1 strain they forecast will reappear this fall and they have to produce pandemic vaccines as early as now to prepare for a turn out as the vaccine may not be as effective will be sure to a big waste of resources with serious results, and there would also be a shortage of seasonal flu vaccine available. Only a few more weeks were needed for the World Health Organization (WHO) and Centers for Disease Control and Prevention) CDC to develop a “seed strain” of the pandemic virus on the first days May, but producers would then need four to six months before they could create large volumes of vaccine.

In other point of view, the WHO will attempt to make sure that a substantial amount is available and should a pandemic be declared and a vaccine produced, for the benefit of developing countries. Vaccine manufacturers and countries with standing orders, such as the U.S. and some European countries will be asked to share with developing countries from the moment the first batches are ready if an H1N1 vaccine is made.

2009-2010 flu seasons are ineffective against the new strain with the previous influenza vaccines for the north and south hemispheres. The WHO claims that two separate immunizations will be required for seasonal and swine flu, but no decision would be made on whether to begin producing a swine flu vaccine. The board will receive inputs from manufacturers (e.g. GlaxoSmithKline, Sanofi-Aventis, Novartis and Baxter International) regarding when they are able to finish manufacturing the seasonal shot and begin production of the swine flu vaccine, waiting from the WHO of their recommendations and “seed virus”, and some may be ready to proceed with production at that time.

There also antiviral drugs available for treatments of influenza, the virus is resistant to amantadine and rimantadine but sensitive to the oseltamivir and zanamivir. There remains concern that this strain may mutate develop resistance to oseltamivir in the future. For the treatment and prevention of the Swine Flu, the CDC recommended the use of Tamiflu (oseltamivir) and Relenza (zanamivir). Studies shows that the medication continues to maintain its effective that why the U.S. government had already extended the shelf life of federally stockpiled Tamiflu from their original five years to seven years.

Buying medications from online sources is not recommended by the WHO because they believed that half of the drugs they sold are counterfeited. Others are thinking if they grab up antiviral drugs for their safe even if they have no symptoms, the health officials warned them may eventually lead them to the Swine Flu virus developing drug resistance.

The Phases of Swine Flu

A process that happens if two different types of influenza virus infected a single cell and it can produce a new strain of influenza is called re-assortment. It will act as a “mixing vessel” in which re-assortment can occur between flu viruses of several species such as pigs are prone to influenza viruses that can also infect both humans and birds. This is because if the virus allows pieces of RNA from different viruses to mix together and form a novel type of virus as a new virus particles are being assembled from a virus splitting between eight independent pieces of RNA.

On the other hand, the World Health Organization raised the pandemic alert level from phase four to phase five, signaling that a pandemic is “imminent”.

To know more about different phases of Swine Flu as defined by the WHO, I enlisted six of them” defined by the WHO:

If a virus circulated among animals but there are no reported cases of infections to humans will fall under phase one. An example of this phase is an outbreak of flu symptoms in your hog race backyard.
In phase two there is an identified animal flu virus and caused infections to human, and it will be considered a potential pandemic threat.

An example is when the owner either the child or an adult within the hog race backyard got infected with a flu from their animal symptoms.
Phase 3 specified that a confirmed animal or human-animal flu virus has caused small outbreaks in human race, but has not resulted in human-to-human transmission that is sufficient to sustain community-level outbreaks. An example in this phase is when a child within the hog race backyard got infected together with his father, his mother and his siblings.

Radically in Phase 4, there is a cause of community-level outbreaks of human-to-human transmission of an animal or human-animal flu virus. This phase will focus to contain the spreading of the virus. The United Nations will then inform different countries asking to advice their people such as traveling to containment areas. All countries with infected with the swine flu must also consider in deploying a pandemic vaccine. An example of this when the infected family member went out from their backyard decided to talk to his friends and unaware that hes spreading the virus.

In the 5th phase, if there are at least two countries in one region and spread the virus by means of human-to-human transmission. The signal of the pandemic is imminently strong. The infected countries are required to advise people with respiratory illnesses to stay home. There should be an advisory of suspension of classes. An example of this is when a man-infected virus either a family member or any of his friends travel to another neighboring country.

The sixth and final phase also called the pandemic phase. A pandemic phase is just like a spread of virus in phase 5 but extended at least one other country outside their geographic region. There must be an implementation of contingency plans of health systems in all levels. An example of this is when a man-infected virus travel to another continent.

Whatever phases of Swine Flu outbreak, we are experiencing in our country or geographic region we must prepare and prevent it to spread to lessen the death toll.

The Lowdown on The 2009 Swine Flu Outbreak

The 2009 outbreak of swine flu or H1N1 virus is recently hugging the limelight due to the potential harm or effects it can have on a patient or on a community. Unfortunately, the source of the virus still cannot be traced.

Before the first case in the United States was discovered, the illness was believed to have started in Mexico which eventually spread to other countries. Recently, the first case of swine flu was reported in
Costa Rica. Alarmed that it could grow into a worldwide flu epidemic, the World Health Organization of the United Nations and the Center for Disease Control Prevention (CDC) in the United States raised its pandemic alert level to Phase 5, which signifies that a “pandemic is imminent.”
While experts believed that the recent outbreak is not as fatal as previous epidemics, such as the SARS virus, health officials believe that the number of cases could go up as the new flu is expected to make its way throughout the United States.

The new swine influenza strain is apparently a new variant of four strains of influenza A virus subtype H1N1. According to the Center for Disease Control and Prevention, one of the strain is endemic in humans and birds and a couple are endemic in pigs.

However, according to scientists the 2009 H1N1 outbreak is of swine origin which is associated with the virus isolated in North America in 1998. To hasten understanding of the current outbreak as well as in coming up with a vaccine, scientists from Canada have completed the full genetic sequencing of the H1N1 virus.

The new strain of H1N1 has become widespread in Mexico and the United States with confirmed cases in 18 countries and suspected cases in 42 others. Travelers have been warned not to travel to affected countries such as Iceland, Singapore, Thailand, South Korea, Hong Kong, Singapore, to name a few.

In addition, warnings have also been issued warnings to visitors of countries affected by the outbreak. It is advisable for visitors to see the doctor right away if they experience flu-like symptoms.
In Mexico, schools, universities, and all public events were suspended from April 24 to May 6, 2009. In the United States, over 400 schools were closed as of May 3, 2009, which included schools in Texas and about 250,000 confirmed or probable cases.

Dr. Keiji Fukuda, who is the Assistant Director-General for Health Securiy and Environment of the World Health Organization confirmed that efforts to control the outbreak is already too late and should now focus on lessening the effects of the virus. He also clarified that closing borders or limiting travel to infected areas will do little in stopping the spread of the H1N1 virus.

On April 28, 2009, the Center for Disease Control and Prevention suggested that as much as possible, people should avoid non-important travel to Mexico.

According to Dr. Ira Longini, who is an expert in the mathematics and statistics of epidemics, staying at home, seeking medical care, closing public venues, and making anti-flu medicines accessible can help reduce the sickness by almost two-thirds.

Finally, according to Dr. Longini, the focus of efforts is to slow transmission until there is a vaccine that can be developed and made available for controlling swine flu outbreaks.