By Julie Stachowiak, PhD
Multiple Sclerosis Guide; Guest blogger

Sure, you might be angry about the delay in vaccines, or the long lines, or what people are calling "empty promises" about the millions of H1N1 (swine flu) vaccine doses that have not yet materialized in expected numbers.

However, if you really want to place the blame on anyone, point your finger at the H1N1 virus itself. It seems like the little guys just do not want to multiply as quickly as seasonal flu in eggs, which is where the virus that is used for vaccine is grown.

To make virus for vaccine, live virus is injected into the tops of eggs, which are then cared for lovingly and kept at just the right temperature for a period of time. It is then harvested and rigorously tested for purity and safety (the entire process from injection of virus into eggs to a vaccine ready to put into a person takes 3 months). To the surprise (and dismay) of companies making the vaccine, they found that the eggs yielded much less virus than was expected, causing a big bottleneck in the vaccine pipeline. Early on, I heard that each egg was providing enough virus for only 1.5 vaccines, whereas the process usually yields enough virus for 4 vaccines per egg.

Company spokespeople and government officials are now assuring people that the problem has been fixed somehow and the virus (and vaccine) production are back on track, so that we should be seeing the millions of doses that we have been expecting very soon.

By Julie Stachowiak, PhD
Multiple Sclerosis Guide; Guest blogger

The simple answer is "it depends who is vaccinated."

Here is the good news and what we DO know. The H1N1 vaccine has an advantage over the seasonal flu vaccine (which has an efficacy of 70 to 90%), because those vaccines are based on educated guesses as to which strains of flu will be circulating a hemisphere away after a good 8 to 10 months has elapsed. Usually the guesses are pretty good, but there can be some "misses."

With H1N1, the vaccine is made of the exact virus that we know is circulating.

Here is something else we do know - one dose of the H1N1 shot has shown to produce adequate immunity in 92 percent of the pregnant women who were immunized.

However, it looks like children probably will still need two doses, as only about one-third of kids under 10 years old developed adequate antibody levels 10 days following the vaccine. It is possible that they could continue to build immunity, and further reports are going to be coming soon (although adults' antibody levels at 10 days post-vaccine and 21 days post-vaccine were about the same).

Also, it is possible that people who are immunocompromised, such as people with HIV, may require two doses to confer immunity. Trials are still ongoing to determine this.

Bottom line: The H1N1 vaccine works. Depending on who is getting vaccinated, two doses may be required.

By Julie Stachowiak, PhD
Multiple Sclerosis Guide; Guest blogger

Good news for anyone taking Lipitor, Crestor, Lescor, Zocor, Pravachol or Mevacor (drugs known as statins) to lower cholesterol - people taking one of these statins who were hospitalized for influenza (seasonal, not H1N1) were 50% less likely to die from the flu or flu complications.

The study looked at the records of 2,800 people who had been hospitalized during the 2007-2008 flu season and found that 2.1 percent of people who were taking statins died, while 3.2 percent of those not taking statins died. After controlling for certain factors, such as age and use of antiviral medications, this indicated that stains lowered risk of death from seasonal influenza by more than half.

One explanation is that statins help by lowering the inflammation that comes with infection and keeps the body from reacting in a dangerous way to the flu. Other researchers say that statins can also result in milder flu symptoms.

Read more about the statin drugs here on About.com's Heart Disease site: The Statin Drugs

By Julie Stachowiak, PhD
Multiple Sclerosis Guide; Guest blogger

A recent study shows that pregnant women who get the flu shot are doing something great for their babies - reducing risk of prematurity and low birth weight.

The US study from Emory University showed that during the whole flu season (October to May), babies born to vaccinated moms were 40 percent less likely to come early. Babies born during the months when the most flu was reported (usually between late November and early March) were 70 percent less likely to be born prematurely.

Other benefits of maternal flu shots to babies include:

• Higher birth weight - babies born to moms who had the shot weighed half a pound more than those born to unvaccinated mothers.
• Protection from flu - babies born to vaccinated moms were less likely to get the flu in their first year of life.

Unfortunately, less than 25 percent of pregnant women get the flu shot in any given season. There are a number of reasons for this - typically, pregnant women are reluctant to get shots or take medicine. Additionally, obstetricians often do not get the vaccine or do not know how to store it properly, according to some experts.

While the above studies looked at seasonal flu vaccines, it is even more important that pregnant women get vaccinated against H1N1 (swine flu), as that virus has proven deadly for pregnant women. Pregnant women are in the highest priority category for receiving the H1N1 shot.

For more information, read this article on About.com's Pregnancy site: What Pregnant Women Need to Know about the H1N1 Flu