Swine Flu and You

Chris Achola

The world wide threat of swine flu epidemic has many people living with HIV concerned about their health and safety. Poznews and Hivsingles check in with WHO and the CDC for the latest. In short: While there are reasons to be cautious, there’s no reason to panic. On April 30th, the US Centers for Disease Control and Prevention (CDC) published information on what is currently known about the symptoms of swine flu, along with recommendations concerning its treatment and prevention. 

Because there are limited data on swine flu, some of the guidance is based upon what is known about seasonal outbreaks of flu in people with HIV.

What is swine flu?

Swine flu is a respiratory disease common among pigs. Though people are not usually susceptible to swine flu, animal-to-human transmission has been documented, notably among farmers working closely with pigs. What’s unique about the particular strain now under surveillance—dubbed influenza type A/H1N1—is its ability to spread from person to person. 

A possible reason for this is the fact that pigs can be infected with not only swine influenza, but also flu viruses that affect humans and birds. The genetic material from multiple influenza viruses can then mix, a process known as reassortment. H1N1 contains genes from two strains of swine flu, one strain of bird flu and one strain of human influenza. In this way, the term "swine flu" is something of a misnomer—we're actually dealing with a new virus that was created in pigs and contains the necessary genetic makeup to spread and cause disease in humans.  

Is swine flu deadly?

All types of influenza that cause disease in humans can be deadly—approximately 200,000 people are hospitalized and 36,000 people die from flu-related complications every year in the United States. 

There is no reason to believe that the swine flu being reported is any more deadly than the regular seasonal flu. Of the 93 confirmed cases of swine flu in humans in the United States as of April 30, only one has resulted in death—a Mexican toddler visiting relatives in Brownsville, Texas. He entered the United States on April 4, became ill on April 8 and died April 27. No other members of his family were infected with the virus. 

No other deaths in the U.S. have been reported, nor have there yet been any fatalities in other countries with laboratory-confirmed cases: Austria, Canada, Germany, Israel, New Zealand, Spain and the United Kingdom.

Many are comparing H1N1 to the Spanish flu pandemic of 1918. Are they similar?

The current influenza infections and the Spanish flu definitely share some common traits. Both involve H1N1 virus and both were first documented at the end of the regular flu season, in spring, and are noted for their tendency to strike young and otherwise healthy people.

It is important to note, however, that initial studies conducted by the CDC and the National Institutes of Health suggest we are currently dealing with an H1N1 strain that's not nearly as lethal as the virus responsible for millions of Spanish flu-related deaths. According to Peter Palese, a microbiologist and influenza expert at Mt. Sinai Medical Center in New York who spoke to the Los Angeles Times, "There are certain characteristics, molecular signatures, which this virus lacks." In particular, the Times summarizes, the swine flu lacks an amino acid that appears to increase the number of virus particles in the lungs and make the disease more deadly.

Some experts caution that H1N1 can mutate to become more easily transmissible or lethal. Thus far, however, there is no evidence to suggest that such genetic changes in the virus are occurring.  

Isn't swine flu now a public health emergency in the United States?

What is of concern to public health experts is the fact that the disease is caused by a new influenza type A virus researchers know very little about, and the fact that the virus has been documented in a number of North American communities. Plus, many of those who died of influenza-like illness in Mexico appeared to be otherwise healthy young adults; in contrast, seasonal influenza tends to be most serious among the very young, the very old and people with other chronic health conditions.

According to the World Health Organization (WHO), H1N1 now calls for “Phase 5” pandemic preparedness planning. This means that the virus has been confirmed in at least two countries in one WHO region. While most countries will not be affected at this stage, the declaration of Phase 5 is "a strong signal that a pandemic is imminent and that the time to finalize the organization, communication, and implementation of the planned mitigation measures is short."

H1N1 has also been declared a public health emergency in the United States. But according to Janet Napolitano, Secretary of the Department of Homeland Security, speaking at a press conference last weekend, "this sounds more severe than it is” and is merely intended to allow funds to be released for public health efforts—such as educational campaigns and close communication with health care providers—and for wider distribution of medications to prevent and treat the infection.

Is swine flu a threat to people living with HIV?

People living with HIV—as well as those with other chronic conditions, such as heart disease, asthma and diabetes—are believed to face an increased risk of serious influenza-related symptoms. According to the CDC, there is often a spike in the number of heart- and lung-related hospitalizations among people living with HIV during the winter influenza season as opposed to other times of the year. Studies also indicate that influenza symptoms might be prolonged and the risks of influenza-related complications—including death—are higher for certain HIV-positive people.

It is not clear if this strain of swine flu poses any more or less of a risk to people living with HIV. One theory: Given that, at least in Mexico, swine flu mimics what was seen during the 1918 pandemic—it appears most serious among people between 18 and 35 years of age; those with healthy immune systems that become hyperactive in response to the virus and causes serious respiratory inflammation and disease—and may be less of a threat to those with compromised immune systems, such as people living with HIV. Unfortunately, it is not clear if this theory will hold up, given that many HIV-positive people are responding well to antiretroviral treatment and have been able to prevent or reverse HIV-induced depletion of the immune system.    

To help prevent seasonal flu, an annual vaccine is recommended for people with HIV to lower the risk of infection or serious disease if infection does occur. Unfortunately, a vaccine has not yet been developed against H1N1. But people living with HIV can take steps to prevent infection.

How can I protect myself?

The CDC and other public health experts list fairly simple ways to prevent the spread of H1N1. These include:

• Cover your nose and mouth with a tissue when you cough or sneeze. Throw the tissue in the trash after you use it.
• Wash your hands often with soap and water, especially after you cough or sneeze. Alcohol-based hand cleaners are also effective.
• Avoid touching your eyes, nose or mouth. Germs spread this way.
• Stay home if you get sick. CDC recommends that you stay home from work or school and limit contact with others to keep from infecting them.
• Very little is known about the benefits of wearing face masks to help control the spread of flu. Whenever possible, instead of relying on face masks, try avoiding close contact and crowded conditions—particularly if swine flu reaches pandemic status.
• No evidence shows that swine flu can be transmitted through food. Eating properly handled pork—cooked to an internal temperature of 160 degrees—is safe.
• Develop a household emergency plan as a precaution. This should include storing a supply of food, medicines, facemasks, alcohol-based hand rubs and other essential supplies.

Reports from the CDC and WHO indicate researchers are now working on a vaccine against H1N1. Though it would likely take at least four months to develop and mass produce a vaccine against H1N1, it could be available in time for a possible second wave of swine flu this coming winter in the northern hemisphere.   

What about medications against swine flu?

Good news. Initial tests suggest that H1N1 is sensitive to two widely available antiviral medications: Relenza (zanamivir) and Tamiflu (oseltamivir).  The flu medications Symmetrel (amantadine) and Flumadine (rimantadine) are not effective against this particular strain of influenza. What's more, there is little evidence to suggest that they cannot be safely combined with antiretrovirals (ARVs) used to treat HIV.

These medications work much like ARVs—they prevent the influenza virus from reproducing in the body. If someone becomes ill with influenza, including H1N1, Relenza or Tamiflu can minimize symptoms and speed up recovery. They may also prevent serious flu complications. For treatment, these medications work best if started soon after getting sick—within two days of symptoms—so call your doctor immediately if you experience flu-related signs. 

According to the CDC, people at high risk of serious influenza-related complications—including people living with HIV/AIDS—can take Relenza or Tamiflu if they are likely to be exposed to other people with influenza. For example, if a family or household member is diagnosed with influenza, the exposed person with HIV/AIDS should take either drug for seven days. Relenza or Tamiflu prescriptions might also be a good idea for HIV-positive people who live in institutions experiencing an influenza outbreak.

With the swine flu designated as a public health emergency, the U.S. government has released 25 percent of the 50 million doses of antiviral medications from the nation’s Strategic National Stockpile