From Geriatric Pharmacy Intern, Amalia Castro, PharmD(c)
Nova Southeastern University College of Pharmacy
The Novel Influenza A, H1N1, or more commonly known as the Swine Flu Virus has caused quite an alarm during the last couple of months in the United States. It has become the most famous virus worldwide after being declared a global pandemic by the World Health Organization (WHO) in early June of this year, due to its sudden spread. According to the Center for Disease Control and Prevention (CDC), the swine flu has affected more than 70 countries and continues to spread around the world. Currently, numerous cases are being reported, especially on the southern half of the earth where flu season has officially begun. This H1N1 virus is transmitted, just like a regular seasonal influenza virus, mainly through coughs, sneezes or infected objects of people sick with this virus. Symptoms include sore throat, cough, body aches, fever, headaches, chills and fatigue.
The two drugs that are currently being used in the fight against the swine flu are the antiviral Tamiflu (oseltamivir) and Relenza (zanamivir). Relenza is an active drug that is inhaled only, which can present a disadvantage for asthmatics or for people with breathing difficulties, and the only form of absorption is through the respiratory tract. On the other hand, Tamiflu is orally absorbed and is a prodrug that has to be converted by the liver to its active form before reaching the rest of the body, making it a vulnerable drug and more prone to resistance.
On July 8th 2009, the World Health Organization was informed of three isolated cases of Tamiflu resistant swine flu. These nonfatal cases we reported in Denmark, China and the Special Administrative Region of Hong Kong, in which all of the patients recovered without any problems. Only one out of these cases links the U.S. to the Tamiflu resistance strain. It was the case of a teenager traveling from San Francisco to Hong Kong who reported flu-like symptoms upon her arrival. After isolating her virus, authorities in Hong Kong were able to find a mutation on a neuraminidase gene that made her resistant to the neuraminidase inhibitor, Tamiflu. The “worrisome” part of all this is that the patient was resistant to this drug without even taking it. Which means that she most likely acquired the resistant strain in U.S. before leaving the country.
The question that arises now is: Can this Tamiflu resistant strain be transmitted from one person to another? Is this strain resistant to the other antiviral drug, Relenza? Currently, there is no proof to show that this resistant strain can be spread from person to person, nor there is evidence to suggest widespread resistance, and certainly no Relenza resistance has been reported yet. Only time will tell.
With Flu season quickly approaching, the government is getting ready to fight against the swine flu virus by granting millions of dollars to fund vaccination drives and preparing hospitals for future cases. Educating the public, as well as, health professionals is another tool they are using in order to prevent chaos once flu season hits the States this fall.
According to the New York Times, vaccinations can start as soon as August if the vaccines prove to be safe and effective. The New England Journal of Medicine announced that pharmaceutical companies such as Novartis AG, which produced its first batch of the H1N1 vaccine back in June, and Baxter International, which has already begun its full-blown production, are working hard to reach their goal of being ready before flu season arrives.
Visit the CDC website for more information and updates on the progress of the swine flu. (http://www.cdc.gov/h1n1flu/)
Nova Southeastern University College of Pharmacy
The Novel Influenza A, H1N1, or more commonly known as the Swine Flu Virus has caused quite an alarm during the last couple of months in the United States. It has become the most famous virus worldwide after being declared a global pandemic by the World Health Organization (WHO) in early June of this year, due to its sudden spread. According to the Center for Disease Control and Prevention (CDC), the swine flu has affected more than 70 countries and continues to spread around the world. Currently, numerous cases are being reported, especially on the southern half of the earth where flu season has officially begun. This H1N1 virus is transmitted, just like a regular seasonal influenza virus, mainly through coughs, sneezes or infected objects of people sick with this virus. Symptoms include sore throat, cough, body aches, fever, headaches, chills and fatigue.
The two drugs that are currently being used in the fight against the swine flu are the antiviral Tamiflu (oseltamivir) and Relenza (zanamivir). Relenza is an active drug that is inhaled only, which can present a disadvantage for asthmatics or for people with breathing difficulties, and the only form of absorption is through the respiratory tract. On the other hand, Tamiflu is orally absorbed and is a prodrug that has to be converted by the liver to its active form before reaching the rest of the body, making it a vulnerable drug and more prone to resistance.
On July 8th 2009, the World Health Organization was informed of three isolated cases of Tamiflu resistant swine flu. These nonfatal cases we reported in Denmark, China and the Special Administrative Region of Hong Kong, in which all of the patients recovered without any problems. Only one out of these cases links the U.S. to the Tamiflu resistance strain. It was the case of a teenager traveling from San Francisco to Hong Kong who reported flu-like symptoms upon her arrival. After isolating her virus, authorities in Hong Kong were able to find a mutation on a neuraminidase gene that made her resistant to the neuraminidase inhibitor, Tamiflu. The “worrisome” part of all this is that the patient was resistant to this drug without even taking it. Which means that she most likely acquired the resistant strain in U.S. before leaving the country.
The question that arises now is: Can this Tamiflu resistant strain be transmitted from one person to another? Is this strain resistant to the other antiviral drug, Relenza? Currently, there is no proof to show that this resistant strain can be spread from person to person, nor there is evidence to suggest widespread resistance, and certainly no Relenza resistance has been reported yet. Only time will tell.
With Flu season quickly approaching, the government is getting ready to fight against the swine flu virus by granting millions of dollars to fund vaccination drives and preparing hospitals for future cases. Educating the public, as well as, health professionals is another tool they are using in order to prevent chaos once flu season hits the States this fall.
According to the New York Times, vaccinations can start as soon as August if the vaccines prove to be safe and effective. The New England Journal of Medicine announced that pharmaceutical companies such as Novartis AG, which produced its first batch of the H1N1 vaccine back in June, and Baxter International, which has already begun its full-blown production, are working hard to reach their goal of being ready before flu season arrives.
Visit the CDC website for more information and updates on the progress of the swine flu. (http://www.cdc.gov/h1n1flu/)