Animal viruses can be more deadly than their human
counterparts

Over those two years, at least three waves of flu struck killing over 600,000 people in the U.S. and a staggering 30-50 million people worldwide.  People died at such a high rate that cities ran out of caskets and dead bodies were stacked on porches and in the streets.

Governments have been concerned that history might repeat itself because the two flues share one thing in common–they both started out as animal viruses.  And our bodies are not particularly good at fighting off viruses new to humans.

Each year a new flock of flu strains kicks off the flu season.  Almost always these strains are variations of human flues from previous years.  What this means is that we have seen cousins of these viruses in the past and so have a leg up on mounting an attack and defeating them.

We do not have this same leg up on animal viruses.  Our immune systems haven't seen anything like them and so can't mount a quick attack.  The end result is that the percentage of people who die from animal flues tends to be much higher than from run of the mill human flues.

In any flu season, the CDC estimates that 5-20% of the U.S. population ends up with the flu.  And that 36,000 of these people die.  The numbers of deaths would be much higher if a truly deadly animal flu virus like the bird flu from a few years back were to emerge and gain the ability to spread from person to person.  (The bird flu was never more than a few isolated cases since it never gained this ability.)

At first blush, this is what the swine flu looked like.  The disease spread easily among people and, in Mexico at least, appeared to be more deadly than normal flues.  So governments around the world sprang into action.  Since flu is spread through contact, governments tried to keep people away from each other.

They closed schools at the fist sign of trouble.  Mexico closed restaurants, theaters and museums too.  All of this was done in an attempt to prevent the spread of a disease like the flu of 1918.

At least outside of Mexico, this flu does not seem to be too much worse than other flues.  So it may be that governments overreacted this time.  But I would prefer that they overreact like this as opposed to ignoring a deadly pandemic.  We don't want another 1918 on our hands.

More info on The 1918 Flu in San Francisco

The swine flu virus. Credit: C. S. Goldsmith and A. Balish, CDC.

As this story is being produced, the reports on swine flu are changing hourly. Cases are popping up closer and closer to home, and the CDC is updating several times a day on the spread of the virus, and plans to fight it.

The $64,000 question is how worried we should be.

Swine flu is largely untreatable: The two effective antiviral drugs, Tamiflu and Relenza, must be taken within 48 hours of infection to stop the spread of the virus.

That leaves a vaccine. Vaccines are relatively straightforward to create, but they take time. If swine flu becomes a deadly pandemic (meaning it's not only widespread — a pandemic – but more lethal than it appears to be so far) the demand for vaccines would likely far outpace supply. According to Art Reingold, at UC Berkeley's School of Public Health, it could take years for doses to reach everyone in the world who's vulnerable to the disease. Here in the US, we have very few vaccine producing facilities, which means we'd be competing with other countries' priorities to treat their own citizens.

Our story focuses on what could, one day, be the answer to pandemics like this one: a universal vaccine. Scientists like Harvard Medical School's Wayne Marasco believe that, in just a few years, we might be able to inoculate ourselves against nearly all influenza viruses – like a tetanus shot, against the flu. Universal vaccines will come too late for our current swine flu pandemic. But they may well be our response to pandemics of the future.

Listen to the Swine Flu and You radio report online.

The swine flu virus, up close (and colorized!)
Credit: C. S. Goldsmith and A. Balish, CDC

Swine Flu has been blanketing the news as of late. On April 29th, the Centers for Disease Control and Prevention (CDC) reported the first US fatality occurring in Texas. The CDC has determined that this swine influenza A(H1N1) virus is contagious and spreading from human to human. Yet at this time, they do not know how easily the virus spreads between people. At our museum, we have taken this very seriously and staff has been asked to stay home if symptoms arise.

CDC is recommending that those who come down with flu-like symptoms stay home from work in order to decrease the rate of infection. The Swine Flu is a viral infection rather than a bacterial infection, which makes it harder to treat. Much of the care for viruses is preventive; viruses are hard to treat after they have entered a living host.

Many people do not know the difference between a viral infection and a bacterial one and consider them interchangeable. Yet they are quite different. Viruses are sub-microscopic particles ranging in size from 20 to 300 nanometers (about 1000 times smaller than the width of a human hair). Viruses must have a living host to function. They remain dormant until they infect a living cell. Within a cell, they then change the genetic material of the cell to replicate the virus. AIDS and Influenza are both created by this process of taking over the normal function of a cell in order to replicate viral cells.

Bacteria do not take over cells. Bacteria are much larger than viruses, usually 10 to 100 times bigger than a virus. Their shapes include curved rods, spheres, rods and spirals. They are known as intercellular organisms because they live between cells. All viruses are harmful to the host because they alter cells, but bacteria can be beneficial (like the species that live in our guts and help us digest our food).

Harmful bacteria in the body create infections like Strep throat or Small Pox. Bacteria can grow and reproduce in both living and non-living environments. Antibiotics are used to treat harmful bacterial growth and infection in the body. Antibiotics; however, are ineffectual against treating viruses.

Because the Swine Flu is a virally spread disease, it is even more important to practice prevention. The CDC sees this disease being spread like a common flu – mainly from person to person through coughing or sneezing by people with influenza. People can also become infected by touching something with flu viruses on it and then touching their mouth or nose. Taking simple precautions like washing your hands and covering your mouth when sneezing is effective prevention. Working in a museum,we take this extra seriously considering how often we come in contact with lots of people and their germs. Many of my co-workers, myself included, have hand sanitizer at our desks, wash our hands often, and carry tissues. It is a simple way to combat an evasive illness.

For more about how to protect yourself from swine flu, check out this podcast from the CDC.

The reasons why African Americans are so burdened with HIV are complicated, says doctor Edward Machtinger, director of the Women's HIV Program at UCSF. The high rate of incarceration of African American men plays an important role, with men carrying HIV back to their female partners when they get out of prison.

HIV/AIDS is a disease of poverty. "Sexually transmitted diseases, in general, disproportionately afflict the poor," says Ruth Greenblatt, who is the founder of the Women's HIV Program and the principal investigator of the Northern California site of the Women's Interagency HIV Study. "If you have poor access to health care, you're less likely to see a doctor early on in your HIV infection, and thus you may be more likely to transmit infection, and you may be less likely to be able to afford condoms and medication."

HIV is now the leading cause of death for African American women between 24 and 35 years old. "Women tend to get sicker and die faster and more often than their male counterparts with HIV," says Machtinger. "One reason is that women don't perceive themselves to be at risk."

In its report, the Black AIDS Institute says that turning the tide is possible, but that it will require better planning and more funding from the federal government, and a stronger commitment from African American leaders. And the report calls for people to get tested. "Knowing your HIV status early can save your life," it concludes.

For patients who have access to drugs, infection with the virus ceased to be a death sentence in 1995, when combinations of drugs called highly active antiretroviral therapy (HAART) were developed. For some patients, drugs can reduce the amount of virus to undetectable levels.

But some virus always hides in the body's immune cells and attacks again if the patient stops taking their medication. Researchers are working on developing a drug to wipe out this latent virus, which could mean the end of AIDS.

Find out more about new research into HIV treatment and a possible cure by watching our HIV Research: Beyond the Vaccine television story report online.