Yesterday was a diary by DWG that went over the Haitian Cholera outbreak. I commented that the outbreak was predicted back in February and someone asked why a vaccine schedule wasn't set up to prevent the outbreak. The same prediction was made for NOLA post Katrina. No Cholera outbreak occurred in NOLA, but that was because the U.S. has a better infrastructure than Haiti.
I'm sure many people in Haiti have been vaccinated. This would include aid workers, key personnel in the Haitian government and I'm sure wealthy Haitians got it (if they didn't leave altogether)
(yes, I know). There are a dozen of so reasons why mass vaccination of the Haitian population didn't happen.
I'll give you several reasons why mass vaccination didn't happen here. This is by no means a all inclusive list. It's just the first ones that came to my mind. NurseKelley (or any other nurse or doctor) may have something to say on the subject if she drops by the comment thread.
- Supply and demand. There isn't that many cases of Cholera world wide, so there isn't a big supply of the vaccine. Out of a world population, estimated around 6.9 billion people, 3-5 million people get Cholera and about 100,00-120-000 deaths occur annually due to Cholera. Taking the high end of the range, that's a world wide incidence rate of 0.0724% (.72 out of 1,000) and a mortality rate of 0.0017% (0.01 out of 1,000). Haiti had a pre-earthquake Cholera incidence rate that was below these numbers. Parts of Asia have prevalence numbers that are much higher and that's where the vaccine is. (The supply is quite limited according to WHO.) Policy makers in Haiti focused on getting public sanitation where it needed to be.
- As vaccines go, the Cholera vaccine isn't that effective. It offers 25-50% protection. People who are vaccinated are also advised to avoid contact with anything likely to be contaminated by Cholera. Most health care policy makers would go for providing safe water over vaccinating everyone, since vaccinated people will have to have clean water anyway.
- There's a lot of disclaimers with the Cholera vaccine. There's quite a few side effects for the benefits. It's not good for babies under 6mo. It hasn't been studied on the elderly, pregnant women or breast feeding women. It's also iffy for people with allergies to dyes and preservatives as well as people with other medical problems. So, you have a whole bunch of people who would want the vaccine, but it would be inappropriate to give it to them; which would inflame the passions of anyone denied the vaccine. Most health care policy makers would go for safe guarding the water supply and providing better sanitation over a mass vaccination program.
- The vaccine needs to be kept cold, but can't be frozen. The environmental needs for the vaccine are between 2-8 degrees Celsius (35-46 degrees F). That is problematic in a country that is really short on air conditioning and refrigeration right now. There are areas of the country where A/C and refrigeration is ok, but it can go out without notice. The problems could be solved, but again, better sanitation is the long term solution.
- The vaccine is delivered via suspension or injection in a series over a week or month and you have to get a booster shot every 6 months thereafter to assure good immunity. The record keeping alone would be overwhelming.
- It's recommended to complete the vaccination series before exposure. That's was out the window by January 30th, 2010.
- The Cholera vaccine isn't available in the United States. The U.S. would be the likely source for getting this vaccine and we don't have it. Which means go back to #1. Most of the vaccine is in areas that have higher Cholera prevalence rates.
- The vaccine doesn't prevent transmission of Cholera. Access to good sanitation has a greater impact on reducing the transmission of Cholera. If the public water is free of Cholera, then transmission will go down.
- Cholera treatment is done with relatively inexpensive fluid and salt replacement therapy. The problem is that Haiti, no doubt, will have a shortage of IV materials and personnel to monitor the lines in a matter of days if they aren't overwhelmed already.
- The Cholera bacteria is adaptable, making the usefulness of the current vaccines chancier.
If DrSteveB or any other physicians show up in this thread; I'm sure they'll add all the medical stuff that this health care administrator forgot.