Alexis' Everything-Medical-About-Where-We're-Going Report

Okay, there are a lot of scary diseases out there, but as long as we exercise basic common sense -- boil/filter water, wash food, avoid snakes, kill mosquitoes, don't eat human flesh -- we should be fine. If you really want a nice summary of all the strange tropical diseases that exist, check out the CDC's pages on Tropical South America and esp. "Other" diseases.

Preventable measures are also nicely outlined by the CDC [check out http://www.cdc.gov/travel/travel.html, as guy says].

They can be summarized briefly as:

  1. protect yourself from animals using DEET and Mosquitoe Netting
  2. avoid unsafe food and water
  3. get the right shots

The right shots to my mind are (In that order of importance):

  1. Tetanus
  2. Hepatitis A
  3. Yellow Fever
  4. Rabies
  5. Typhoid

TELL YOUR MD IF YOU ARE:

  1. immunocompromised (HIV+)
  2. allergic to Eggs
  3. pregnant
  4. have a seizure disorder

The following dates are DEADLINES in order to ensure adequate vaccination for a departure date of 21 Feb 98.

21 Jan 98Tetanus (Toxoid, not immunoglobulin)
Hepatitis A (Havirax)
Rabies #1/3 (HDCV IM)

28 Jan 98 Yellow Fever (get certificate see link below)
Rabies #2/3 (one week later)

12 Feb 98 Typhoid (ViCS injectable)
Rabies #3/3 (one to two weeks later)

14 Feb 98 Begin Larium (not Chloroquine)

21 Feb 98 Call MD (with adverse effects of Larium)
Begin new anti-malarial prophylaxis if necessary
[alternates: http://www.cdc.gov/travel/rx_malar.htm]

Departure [yellow fever certificate http://www.cdc.gov/travel/vacccert.htm]


THE JUSTIFICATION FOR THE TIMETABLE

Hepatitis A is effective if given 4 weeks before travel, otherwise it must be given with an additional medication called an immunoglobulin (IG). IG may interfere with the efficacy of the other vaccinations. If IG is used, then it should be given AFTER the other vaccinations are complete.

It takes (on average) two weeks for a vaccine to become fully protective.

The Rabies series should be completed before starting malaria prophylaxis, because chloroquine interferes with its efficacy. The CDC says Larium does as well, so do not start Larium until two days after the last rabies dose. (Logically, you should wait two weeks, but you don't have to.)

Although you could take the Yellow Fever, Typhoid, Hepatitis and Rabies all on the first day, this will likely be accompanied by more severe side effects than by splitting them up.

Waiting until the last minute to call your MD with Larium side effects is cutting it close. However, the chance you'll have to stop is slim and you'll have some anti-malarial in your system before your trip begins.

THE JUSTIFICATION OF THIS CHOICE OF VACCINES

TETANUS

If you can remember a tetanus shot in the last 5 years, or if you can document one in the last 10 years, Then you don't need another one. In fact, studies have shown that getting them more often than every ten years increases the adverse effects of every subsequent tetanus shot you get.

Tetanus is actual a toxin and the shot stimulates your body to make an anti-toxin. The bacteria that make the toxin live on rusty nails (no joke) and if you don't already have a healthy supply of anti-toxin before they jab you, you'll probably die. Tetanus toxoid looks like the toxin (i.e., as opposed to the bacteria) and stimulates your immune system to produce anti-toxin antibodies (also called immunoglobulins) so they can inactivate the tetanus toxin right away. If you do step on a rusty nail, then the ER people will give you an injection of anti-toxin called an immunoglobulin (IG) just to make sure. It's a lot like getting snake anti-venom. This is useful immediately after exposure, but you don't want any IG before the trip, you want the Tetanus toxoid.

HEPATITIS A

This is a self-limited illness with a very low mortality rate. The worldwide prevalence is extremely high and the virus is easily passed from person to person through the fecal-oral route. Once you've had it, you're immune for life. But having it is unpleasant -- your liver swells up, you turn yellow, have diarrhea, fevers, sweats -- it's a real pain. The vaccine is safe and effective. Havirax and Vaqta are made in the US and are safer than others.

HEPATITIS B

This is a good vaccine and worth it, but it takes six months to get all the shots. There is a new accelerated course of four shots and (if interested) ask if it's available. Hep. B is a nasty disease, so why risk it. However, it is transmitted the same way as HIV, so your risk probably doesn't merit it.

Hepatitis just means inflammation of the liver. There are lots of different types of hepatitis, they are labelled A, B, C, D, and E. A and E are transmitted through contaminated food/water and you get them once and then have life long immunity. D is a defective virus that depends on B to survive, but getting both means a really bad course of B. B and C are the worst. B and C can cause a chronic infection for life. They are transmitted through needle-sharing, sex, and through contaminated blood. They are more transmissable than HIV.

The viruses infect the liver and eventually your liver fails. You aren't eligible for transplant because your blood would just infect the new liver. Once your liver fails, you don't make proteins necessary for good blood clotting and you become a hemophiliac. Then one day you start bleeding and don't stop. Transfusions of blood and blood products might work, but usually don't. Watching people die this way is particularly agonizing since you can't keep transfusing them forever, but you could transfuse them for just another day. Most patients become encephalopathic (delirious) before they bleed. This is also how most end-stage alcoholics die.

RABIES

These shots are a major pain in the neck (three in all over 21 to 28 days) and they will hurt more than the others. However rabies is carried in two populations of animals -- domestic (dogs) and wild (bats, rodents). Rabies is reportedly especially prevalent in the Darien Gap. Travel guides recommend vaccine and a machete. Rabies is almost uniformly fatal (>99%). If you haven't had the vaccine and you get bitten then you have to have six days of 19 shots (over 91 days). If you have had the 3 shots of the vaccine, then you only need 2 more shots over 3 days. I recommend the vaccine because of the risk of the (rural) area, the lethality of the disease, and the complex post-exposure treatment course.

While there are only 1000 cases of rabies/year in the US, there are over 1,000,000 animal bites. Most ER MD s offer post-exposure rabies vaccine for bites that are (a) from animals acting strangely or (b) extensive. Post-exposure treatment includes vigorous washing of the bite, killing the animal and saving the head (to check for rabies virus later or observing animal for ten days for bizarre behaviour), and a post-exposure medication therapy of 1mL IM vaccine injections (1 on each of days 0,3,7,14,and 28) PLUS 0.1mL ID immunoglobulin (8 shots on day 0, 4 on day 7, 1 on day 28, 1 on day 91) or (if pre-vaccinated) two additional doses of HCDV on days 0 and 3 only.

Everyone has heard horror stories about rabies, it is probably worse than you think. It infects your brain and then preferentially replicates in the cortex (the part you think consciously with).

YELLOW FEVER

This is not required for travel in Panama. However the CDC reccommends it in both Panama and Colombia. It is required for travel to some countries [see http://www.cdc.gov/travel/yelfever.htm] Moreoever, Yellow Fever carries a mortality rate of 5-10%. Be sure to get a certificate (downloadable example at http://www.cdc.gov/travel/vacccert.htm) signed by your MD -- he also needs to stamp it (with his license number). Be sure he dates it correctly, it becomes valid only 10 days after vaccination.

Yellow Fever is transmitted by mosquitoes. Mortality is at 5%, mostly from internal bleeding. There is no treatment.

TYPHOID

This is not the greatest vaccine. It only confers 70-90% protection. There is a new injectable kind called ViCS. You can have it with any other vaccines at the same time. Then again, who wants diarrhea.

CHOLERA

This was a tough decision. There is an awful lot of cholera where we will be. But the vaccine only affords 50% protection, which is extremely poor for a vaccine. Most vaccines are 99 % effective. If you decide to get this vaccine, then ask about it early, there are two injections and it cannot be given with the yellow fever vaccine.

MALARIA

The type of malaria in this area is cholorquine resistant. You should take Larium and watch for side effects. There are workable alternate regimens (http://www.cdc.gov/travel/rx_malar.htm).

Malaria tends to be especially severe the first time you get it. This area is full of mosquitoes and full of warm shallow ponds to grow them in. Malaria will make you very sick. This region's particular type of malaria (Falciparum) is especially dangerous, can cause coma followed by death in a matter of days. Cerebral Malaria (infection of the brain) tends to occur more often in first timers (e.g., travellers), too.

That is probably more information than you wanted, feel free to write with specific questions.

And if somehow you still want more info...

From the Center for Disease Control:

Summary of Recommendations for MEXICO and CENTRAL AMERICA:

Travelers should (1) take the appropriate country specific malaria prevention measures (chloroquine or mefloquine (or equivalent), (2) follow precautions to prevent insect bites, (3) pay attention to the quality of their drinking water and food, (4) have a dose of Immune Globulin (IG) or the Hepatitis A vaccine, and (5) consider a booster dose of tetanus (Td) vaccine. (6) Depending on the locations to be visited, planned activities, and health of the traveler, the following vaccines should be considered: Hepatitis B, Yellow Fever, Typhoid, Rabies (pre-exposure), and Cholera. Details for these recommendations are found in this document. (7) Finally, the normal "childhood" vaccines should be up-to-date: Measles, Mumps, Rubella (MMR Vaccine); Diphtheria, Tetanus, Pertussis (DTP Vaccine) [ < 7 years of age], and Polio vaccine. Refer to: Vaccine Recommendations - Infants & Children less than 2 Years of Age; Vaccine Recommendations - 2 years of Age and Older. For further information on food and water precautions refer to "Traveler's Diarrhea & Food and Water Precautions." Pregnant travelers or travelers with children should check the CDC Travel Page for additional information.

This information comes from http://www.cdc.gov/travel/camerica.htm

From the World Health Organization:

Mainland Middle America (Belize, Costa Rica, El Salvador, Guatemala, Honduras, Mexico, Nicaragua, and Panama) ranges from the deserts of the north to the tropical rain forests of the south-east.

Of the arthropod-borne diseases, malaria and cutaneous and mucocutaneous leishmaniasis occur in all eight countries. Visceral leishmaniasis occurs in El Salvador, Guatemala, Honduras and Mexico. Onchocerciasis (river blindness) is found in two small foci in the south of Mexico and four dispersed foci in Guatemala. American trypanosomiasis (Chagas disease) has been reported to occur in localized foci in rural areas in all eight countries. Bancroftian filariasis is present in Costa Rica. Dengue fever and Venezuelan equine encephalitis may occur in all countries.

The food-borne and water-borne diseases, including amoebic and bacillary dysenteries and other diarrhoeal diseases, and the typhoid fevers are very common throughout the area. All countries except Panama reported cases of cholera in 1995. Hepatitis A occurs throughout the area and hepatitis E has been reported in Mexico. Helminthic infections are common. Paragonimiasis (oriental lung fluke) has been reported in Costa Rica, Honduras and Panama. Brucellosis occurs in the northern part of the area. Many Salmonella typhi infections from Mexico and Shigella dysenteriae type 1 infections from mainland Middle America as a whole have been caused by drug-resistant enterobacteria.

Other diseases. Rabies in animals (usually dogs and bats) is widespread throughout the area. Snakes may be a hazard in some areas.

This information comes from http://jupiter.who.ch/yellow/welcome.htm

Specific Eclipse Health

We need to have enough solar filters to safely look at the sun during the partial phases of the eclipse. Aluminated mylar glasses are good and cheap, but scratchable. Bulkier but more reliable are pieces of No. 14 welder's glass. It must be No. 14... any other rating is not strong enough. NASA maintains a list of suppliers for solar viewing glasses and filters.

Also, these things are cheap, no more than $2 each. So bring extras... too many is better than not enough, and maybe we can save some locals from going blind.

Alexis should be in the process of putting together a more complete summary.