Tue | Jul 17, 2018

Why H1N1 is no longer swine flu

Published:Wednesday | March 30, 2016 | 12:00 AMAnastasia Cunningham

Although the H1N1 influenza (flu) virus is often referred to as the swine flu, that is no longer the case. The association was made because when it was first detected in 2009, the virus was similar to those found in pigs, and persons who caught it had had direct contact with pigs.

That changed several years ago, when a new virus emerged that spread among persons who had not been near pigs. Flu viruses are constantly changing, so it's not unusual for new ones to appear each year.

Today, the H1N1 virus is a human seasonal flu virus that also circulates in pigs. It is important to note, however, that although the virus also circulates in pigs, you cannot get it by eating properly handled and cooked pork, bacon, ham or pork products.

In 2009, H1N1 was spreading fast around the world, forcing the World Health Organization (WHO) to call it a pandemic.




Since then, cases continue to develop around the world with new strains, but not as bad. However, while the H1N1 is milder than few years ago, it still poses a threat, especially to persons in high-risk groups - children younger than five years, persons 65 years and older, pregnant women, persons with pre-existing medical conditions, and persons with weakened immune systems.

According to the WHO, influenza in general occurs globally with an annual attack rate estimated at five to 10 per cent in adults and 20 to 30 per cent in children. Illnesses can result in hospitalisation and death, mainly among the high-risk groups. Worldwide, these annual epidemics are estimated to result in about three to five million cases of severe illness, and about 250,000 to 500,000 deaths.

It is highly recommend that persons get their annual flu vaccine, especially those at greater risk as well as health-care workers.


Types of influenza


There are three types of flu viruses: A, B, and C.

1. Type A influenza virus - This type generally affects birds like ducks and chicken, and in some cases, humans. There are three variants of Type A influenza viruses: H1N1, which is very contagious and potentially fatal; H1N2; and H1N3. Type A flu virus is constantly changing and is generally responsible for the large flu epidemics.

2. Type B flu Virus - This type only infects humans and causes mild fever and is less harmful than Type A flu.

3. Type C flu virus - This type only infects humans and causes mild respiratory infections. The symptoms of Type C influenza resembles the symptoms of the common cold and is not pandemic.




Yearly influenza epidemics can seriously affect all populations, but the highest risk of complications occur among children younger than age five years and especially younger than two years; adults aged 65 years or older; pregnant women; persons of any age with certain medical conditions, such as chronic heart, lung, kidney, liver, blood or metabolic diseases (such as diabetes), any non-communicable disease, respiratory illnesses (asthma, bronchitis, etc); and persons with weakened immune systems.

Deaths are usually among persons in these high-risk groups.




Seasonal influenza, including H1N1, is highly contagious and spreads quite easily, sweeping through close-knit, highly populated areas like schools, workplaces, hospitals, children's homes, homes for the elderly, communities, etc.

It spreads from one infected person to others via:

- Coughing. When an infected person coughs, infected droplets get into the air and another person can breathe them in and be exposed.

- Sneezing

- Talking closely to persons

- Kissing

- Handshake

- Other forms of intimacy

At times, persons may become infected by touching a surface or object which was touched by an infected person, and then they may touch their faces (nose, mouth and eyes) and become infected.

Influenza is transmitted to a healthy person from an infected person through tiny droplets expelled from a runny nose or during sneezing, breathing or coughing. People with weak immune systems are more prone to getting infected.

Once the virus attaches itself to cell receptors, it replicates in large quantities and invades the entire body.

Infected persons can spread the virus one day before displaying symptoms and up to seven days after getting the virus. Children can be contagious for as long as 10 days.




Seasonal influenza is characterised by a sudden onset of high fever, cough (usually dry), headache, muscle and joint pain, severe malaise (feeling unwell), sore throat and runny nose. Cough can be severe and can last two or more weeks.

H1N1 symptoms are similar to any seasonal flu. They can include:

- Cough

- Fever

- Sore throat

- Stuffy or runny nose

- Muscle and joints aches and pains

- Headache

- Chills

- Fatigue

Some persons also have irritated eyes, wheezing, shortness of breath, abdominal and side pain, dizziness, confusion, vomiting and diarrhoea.

Like the regular flu, H1N1 can lead to more serious problems, including pneumonia, lung infection, and other respiratory problems. And it can make illnesses like diabetes or asthma worse.

If you are displaying the more severe symptoms, seek immediate medical attention.

Most people recover from fever and other symptoms within a week without requiring medical attention. But influenza can cause severe illness or death, especially in people at high risk.

The time from infection to illness, known as the incubation period, is about two days.




Because H1N1 presents with similar symptoms as other seasonal flu viruses, a lab test is the only way to confirm it. Here in Jamaica, it is classified as a category one illness, so medical practitioners must report all suspected cases within 24 hours to the health authorities. The samples will be sent to the Public Health Lab, which will then be sent to the newly upgraded Virology Laboratory at the University of the West Indies for testing and confirmation. Results are expected within a few days.




Recovery from H1N1 is largely dependent on bed rest, cough suppressants, increased fluid consumption, medication for fever and pain, and strengthening the immune system.

Severe cases may require intravenous hydration and other supportive measures. Antiviral agents may also be considered for treatment, or as a prophylaxis. Tamiflu is the chief medication used for severe cases.

Antibiotics are useless to fight the flu because the flu is caused by a virus, not bacteria.

Do not give aspirin or medication containing aspirin to children under age 18 because of the risk of Reye's syndrome.