Disease Risks and Precautions
in Tropical South America
The material
provided below is for informational purposes only.
It may not be current, and it should not be considered definitive.
All travelers
should check the Center for Disease Control (CDC) website
for the most current disease risk and disease prevention information.
DISEASES
TRANSMITTED BY INSECTS
DISEASES TRANSMITTED THROUGH
FOOD AND WATER
DISEASES TRANSMITTED THROUGH
INTIMATE CONTACT
OTHER DISEASES
RECOMMENDATIONS FOR TROPICAL
SOUTH AMERICA
COUNTRIES IN REGION
Bolivia, Brazil, Colombia, Ecuador, French Guiana, Guyana, Paraguay,
Peru, Suriname, and Venezuela
GENERAL PRECAUTIONS
Travelers to Tropical South America may be exposed to potential
diseases from a number of sources. The most frequently reported
illness is traveler's diarrhea, but there are other diseases which
are unique to Mexico and Central America or the tropics. These
diseases are transmitted by insects, contaminated food and water,
or close contact with infected people. Specific diseases are discussed
under each of these topical headings.
In order to reduce the risk of infection travelers must (1) protect
themselves from insects, (2) ensure the quality of their food
and drinking water, and (3) be knowledgeable about potential diseases
in the region to be visited. Finally, diseases are not restricted
to cleanly defined geographical areas, i.e. mosquitoes can fly
over city or country borders, therefore, all travelers should
protect themselves by taking the basic preventive precautions.
DISEASES TRANSMITTED BY INSECTS
Many diseases are transmitted through the bite of infected insects
such as mosquitoes, flies, fleas, ticks, and lice. In general
travelers must protect themselves from insect bites by wearing
proper clothing, using bednets, applying an insect repellent to
exposed skin and clothing, and if possible, avoiding high risk
situations, i.e. outdoor activities during night time hours from
dusk to dawn when mosquitoes bite, unscreened living accommodations,
etc. If a mosquito net is unlikely to be available, consideration
should be given to purchasing a portable mosquito net.
MALARIA
Risk: Malaria exists throughout the year in many parts of the
Tropical South American countries including some urban areas.
P. falciparum (the most dangerous type), which has been reported
to be resistant to the drug chloroquine, has been confirmed in
most of these countries. Detailed risk
information: Bolivia: Malaria risk in rural areas only, except
no risk in the highland areas, i.e. Departments of Oruro, Southern
and Central Potosi, La Paz, and the Provinces of Ingavi, Los Andes,
Omasuyos, and Pacajes. Brazil: Malaria risk in Acre and Rondonia
States, Territories of Amapa and Roraima, and in rural areas of
Amazonas, Goia s, Maranahao, Mato Grosso,
and Para States. Travelers who will only visit the coastal states
from the "horn" south to the Uruguay border, including
Iguassu Falls, are not at risk and need not take preventive drugs.
Colombia: Malaria risk in rural areas only except no risk in Bogota
and vicinity. Malaria risk in the rural areas of Uraba (Antioquia
Dept.), Bajo Cauca-Nechi (Cauca and Antioquia Dept.), Magdalena
Medio, Caqueta (Caqueta Intendencia), Sarare (Arauca Intendencia),
Catatumbo (Norte de Santander Dept.), Pacifico Central and Sur,
Putumayo (Putumayo Intendencia), Ariari (Meta Dept.), Alto Vaupes(Vaupes
Comisaria), Amazonas, and Guainia (Comisarias). Ecuador: Malaria
risk in all areas in the providences along the eastern border
and the Pacific coast, i.e., El Oro, Esmeraldas, Guayas (including
Guayaquil), Los Rios, Manabi, Morona-Santiago, Napo, Pastaza,
Pichincha, and
Zamora-Chinchipe provinces. Travelers who visit only Quito and
vicinity, the central highlands tourist areas, or the Galapagos
Islands are not at risk and need not take preventive drugs. French
Guiana: Malaria risk in all areas. Guyana: Malaria risk in rural
areas in the southern interior and northwest coast, i.e., Rupununi
and North West Regions. Paraguay: Malaria risk in rural areas
bordering Brazil. Peru: Malaria risk exists in rural areas. Travelers
who will only visit Lima and vicinity, coastal areas south of
Lima, or the highland tourist areas of Cuzco, Machu Picchu, or
Lake Titicaca are not at risk and need not take preventive drugs.
Risk exists in rural areas of Departments of Amazonas, Cajamarca
(except Hualgayoc Prov.), La Libertad (except Otuxco, Santiago
de Chuco Prov.) Lambayeque, Loreto, Piura, (except Talara Prov.)
San Martin and Tumbes, Provinces of Santa (Ancash Dept.); parts
of La Convension (Cuzco Dept.), Tayacaja (Huancavelica Dept.),
Satipo (Junin Dept.). Suriname: Malaria risk exist in rural areas,
except no risk in the Paramaribo District and the coastal area
north of 5o N. Lat. Venezuela: Malaria risk exists in rural areas
of all border states and territories and the states of Barinas,
Merida, and Portuguesa. Travelers should note that regardless
of preventive method employed, it is still possible to
contract malaria. P. falciparum is reported in all these countries,
but less so in Peru and Paraguay. P. falciparum highly resistant
to chloroquine and Fansidar is reported.
Prevention: Most travelers to tropical South America (including
travelers to Peru's eastern and northern border provinces) at
risk for malaria should take MEFLOQUINE to prevent malaria. This
drug is marketed in the United States under the name Lariam. The
adult dosage is 250 mg (one tablet) once a week. MEFLOQUINE should
be taken one week before leaving, weekly while in the malarious
area, and weekly for 4 weeks after leaving the malarious area.
Minor side effects one may experience while taking MEFLOQUINE
include gastrointestinal disturbances and dizziness. More serious
side effects at the recommended dosage have rarely occurred. Consult
a physician for other precautions.
Mefloquine should NOT be used by:
- travelers with a history of epilepsy or psychiatric disorder,
- travelers with a known hypersensitivity to mefloquine.
In consultation with a physician, mefloquine may be used by pregnant
women and children less than 30 pounds, when travel to an area
with choloroquine- resistant malaria is unavoidable
Travelers to all areas of Peru, except the eastern and northern
border provinces, and Paraguay should take CHLOROQUINE to prevent
malaria. The weekly dosage for an adult is 500 mg once a week.
This drug should be taken one week before entering a malarious
area, weekly while there, and
weekly for 4 weeks after leaving the malarious area. For these
areas in Peru, no other anti-malarial drugs are needed.
In addition to using drugs to prevent malaria, travelers should
use measures to reduce exposure to malaria-carrying mosquitoes,
and protect themselves from mosquito bites. These mosquitoes bite
mainly during the evening and night, from dusk to dawn.
YELLOW FEVER
Risk: Outbreaks of yellow fever have occurred in Bolivia, and
Peru. Yellow fever is not always active in all countries of this
region, but there is a significant risk to all travelers throughout
the year, especially in travel or visits to rural settings. Areas
of higher risk: Bolivia: the Departments of Beni, Chuquisaca,
Cochabamba, Pando, Santa Cruz, Tarija, and part of La Paz. Brazil:
rural areas of Acre, Amazonas, Goias, Maranhao, Mato Grosso, Mato
Grosso do Sul, Para, and Rondonia States; and the Territories
of Amapa and Roraima. Colombia: middle valley of the Magdalena
River, foothills of the Cordllera Oriental from border of Ecuador
to Venezuela, Uraba, foothills of Sierra Nevada, Orinoquia, and
Amazonia. Peru: central and northern jungle regions. Venezuela:
State of Bolivar, forest around Lake Maracaibo, and San Camilo
jungle. Ecuador, French Guiana, Guyana, Paraguay, and Suriname
have reported only a few cases.
Prevention: In general, if you are traveling to an area of risk,
the easiest and safest thing to do is to get a yellow fever vaccination
and a signed certificate. Yellow fever vaccination, a one dose
shot, may be administered to adults and children over 9 months
of age. The vaccine is not recommended for persons who are pregnant
or whose immune systems are not functioning normally. In addition
to the vaccine, travelers should use measures to reduce exposure
to mosquitoes, and protect themselves from mosquito bites. These
mosquitoes bite mainly during the evening and morning hours.
CDC recommends and many countries require a yellow fever vaccination.
French Guiana requires a yellow fever certificate for all travelers.
Bolivia, Brazil (age 6 months), Ecuador, Guyana, Peru (age 6 months),
and Suriname, require a yellow fever vaccination for all travelers
(Age > 1) arriving from all "Infected Countries".
Paraguay requires a certificate for travelers leaving the country
to "Infected Countries".
Brazil, Bolivia, Colombia and Peru, recommend a vaccination, especially
if visiting rural areas.
In addition if you are traveling TO / FROM a country listed below
you are required to have a yellow fever vaccination.
TRAVELING FROM "ENDEMIC" YELLOW FEVER INFECTED COUNTRIES
BELOW:
Africa:
Angola
Benin
Burundi
Burkina Faso
Cameroon
Central African
Republic
Chad
Congo
Cote d'Ivoire,
(Ivory Coast)
Equatorial Guinea
Ethiopia
Gabon
Gambia
Ghana
Guinea
Guinea Bissau
Kenya
Liberia
Mali
Mauritania
Niger
Nigeria
Rwanda
Sao Tome and Principe
Senegal
Sierra Leone
Somalia
Sudan
Tanzania
Togo
Uganda
Zaire
South America:
Bolivia
Brazil
Colombia
Ecuador
French Guiana
Guyana
Panama
Peru
Suriname
Venezuela
TRAVELING TO TROPICAL SOUTH AMERICAN COUNTRIES BELOW:
Bolivia
Brazil
Ecuador
French Guiana
Guyana**
Peru
Suriname
**for Guyana, add Belize, Costa Rica, Guatemala, Honduras, and
Nicaragua to the list of "FROM" countries
Yellow Fever Certificate: After immunization an International
Certificate of Vaccination is issued and is valid 10 days after
vaccination to meet entry and exit requirements for all countries.
The Certificate is good for 10 years. You must take the certificate
with you. Yellow fever vaccine is the ONLY vaccine that may be
officially required for entry into certain countries.
DENGUE FEVER
Risk: Dengue fever occurs naturally throughout Tropical South
America with recent epidemics in Brazil, Colombia, Ecuador, French
Guiana, Surinam, Venezuela, and the tropical parts of Bolivia,
Paraguay and Peru. The risk of infection is small for most travelers
except during periods of epidemic transmission.
Prevention: There is no vaccine for dengue fever therefore the
traveler should avoid mosquito bites. These mosquitoes bite mainly
in the daytime.
OTHER INSECT DISEASES
Risks: Other diseases spread by mosquitoes, sand flies, black
flies, or other insects are prevalent, especially in rural areas.
These diseases include: Filariasis (mosquito), leishmaniasis (sandfly),
Onchocerciasis (blackflies), Trypanosomiasis, American Chagas'
Disease ("cone nose or kissing" bug), Oropouche Virus
(gnats or midges), typhus (lice), and Plague (fleas).
PREVENTING INSECT BITES
To reduce mosquito bites travelers should remain in well-screened
areas, use mosquito nets, and wear clothes that cover most of
the body. Travelers should also take insect repellent with them
to use on any exposed areas of the skin. The most effective repellent
is DEET (N,N-diethyl meta-toluamide) an ingredient in most insect
repellents. Travelers should also purchase a flying insect-killing
spray to use in living and sleeping areas during the evening and
night. For greater protection clothing and bednets can be soaked
in or sprayed with PERMETHRIN, which is an insect repellent licensed
for use on clothing. If applied according to the directions, permethrin
will repel insects
from clothing for several weeks.
DISEASES TRANSMITTED THROUGH FOOD AND WATER
Food and waterborne diseases are the number
one cause of illness to travelers and are very common in Temperate
South America. Traveler's diarrhea is the most frequent health
problem for travelers. It can be caused by viruses, bacteria,
or parasites which are found universally throughout the region.
Transmission is most often through contaminated food or water.
Infections cause diarrhea and vomiting (typhoid fever, cholera,
and parasites), liver damage (hepatitis), or muscle paralysis
(polio).
CHOLERA
Risk: A recent epidemic of cholera has swept through the entire
Tropical South American area. The majority of cases have been
reported from Peru, Ecuador, Colombia, Guatemala, and Mexico.
Cholera has been reported in coastal cities and inland areas of
most of these countries. Cholera has also been reported in Cuzco
in Peru and in the Galapagos Islands of Ecuador. Other countries
to report cases include Argentina, Belize, Bolivia, Brazil, Chile,
Costa Rica, El Salvador, French Guiana, Guyana, Honduras, Nicaragua,
Panama, Suriname, and Venezuela. Bolivia has reported cases from
the departments of Oruro and La Paz. Cholera has been reported
from five states in Brazil: Amazonas, Mato Grosso, Rondonia, Amapa,
and Para. Several municipalities near the mouth of the Amazon
River have been affected. Cholera cases were first recognized
in Peru in the last week of January 1991. Cholera has been reported
in a small number of U.S. residents traveling to Peru and Ecuador.
The risk of infection to the U. S. traveler is very low, especially
those that are following the usual tourist itineraries and staying
in standard accommodations. Travelers should consider the vaccine
if they have any problems with their stomach, such as anti-acid
therapy, ulcers, or if they will be living in less than sanitary
conditions in areas of high cholera activity.
Prevention: Travelers to cholera infected areas should follow
the standard food and water precautions of eating only thoroughly
cooked food, peeling their own fruit, and drinking either boiled
water, bottled carbonated water, or bottled carbonated soft drinks.
Persons with severe cases respond well to simple fluid and electrolyte-replacement
therapy, but medical attention must be sought quickly when cholera
is suspected. The available vaccine is only 50% effective in reducing
the illness, and is not recommended routinely for travelers.
TYPHOID FEVER
Risk: Travelers to Tropical South America are at risk for typhoid
fever, especially when traveling to smaller cities, villages,
or rural areas. Typhoid fever is more common in Brazil, Colombia,
Ecuador, French Guiana, and Peru.
Prevention: By drinking only bottled or boiled water and eating
only thoroughly cooked food, a traveler lowers the risk of infection.
Currently available vaccines have been shown to protect 70- 90%
of the recipients. Therefore, even vaccinated travelers should
be cautious in selecting their food and water. Two available vaccines
provide equivalent protection against typhoid fever- oral and
injectable.
Recommendations: CDC recommends a typhoid vaccination for those
travelers who are going off the usual tourist itineraries, traveling
to smaller cities and rural areas, or staying long term, that
is, a traveler for six weeks or more. Typhoid vaccination is not
required for international travel.
HEPATITIS A
Risk: Travelers are at high risk for Hepatitis A, especially if
travel plans include visiting rural areas and extensive travel
in the countryside, frequent close contact with local persons,
or eating in settings of poor sanitation. A study has shown that
many cases of travel-related hepatitis A occur in travelers to
developing countries with "standard" itineraries, accommodations,
and food consumption behaviors.
Prevention: The virus is inactivated by boiling or cooking to
85 degrees centigrade for one minute, therefore eating thoroughly
cooked foods and drinking only treated water serve as general
precautions. Havrix, the hepatitis A vaccine currently licensed
for use in the U.S., or immune globulin (IG) is recommended before
travel for persons 2 years of age orolder. Hepatitis A vaccine
is preferred for persons who plan to travel repeatedly or reside
for long periods of time in intermediate or high risk areas.
Recommendations: CDC recommends hepatitis A vaccine or IG for
protection against hepatitis A. Immune globulin should be used
for travelers < 2 years of age. Immune globulin is recommended
for persons of all ages who desire only short term protection.
PARASITES
Parasitic infections are acquired by eating or drinking contaminated
food or water, through direct contact with soil or water containing
parasites or their larva, or by contact with biting insects.
Symptoms and evidence of infection may include, but are not limited
to fever, swollen lymph nodes, rashes or itchy skin, digestive
problems such as abdominal pain or diarrhea, eye problems, and
anaemia.
Risk: Travelers to Tropical South America are at risk of parasitic
infections. There are many types of parasites and infection may
occur in several ways: by eating undercooked meats infected with
parasites or their larva; by eating food or drinking water contaminated
with parasites or their eggs; by contact with soil or water infected
with parasites; or through insect bites. Several types of parasites
can penetrate intact skin and travelers are advised to wear shoes
and avoid swimming, wading, or washing in fresh water.
Prevention: Travelers should eat only thoroughly cooked food,
drink safe water, wear shoes, refrain from swimming in fresh water,
and avoid contact with insects, particularly mosquitoes, biting
flies, gnats, and midges.
DISEASES TRANSMITTED THROUGH INTIMATE CONTACT
HIV / AIDS
Risk: AIDS is found throughout the region. In Tropical America,
heterosexual transmission is now the predominant mode of transmission,
with the largest number of cases in males, and there are high
numbers of HIV-positive injecting drug users. The risk to a traveler
depends on whether the traveler will be involved in sexual or
needle-sharing contact with a person who is infected with HIV.
Receipt of unscreened blood for transfusion poses a risk for HIV
infection.
Prevention: No effective vaccine has been developed for HIV. Travelers
should avoid sexual or needle-sharing contact with a person who
is infected with HIV. If a blood transfusion is necessary, screened
blood should be from an HIV-negative blood donor.
Recommendations: Travelers should avoid activities known to carry
risks for infection with HIV.
HEPATITIS B
Risk: The risk of Hepatitis B virus infection is highest in the
interior Amazon Region and moderate for the rest of Tropical South
America. The risk to the individual international traveler is
determined by the extent of: (1) direct contact with blood or
other body fluids, etc.; (2) intimate sexual contact with an infected
person; (3) the duration of travel.
Prevention: The primary prevention consists of either vaccination
and/or reducing intimate contact with those suspected of being
infected. For those travelers expecting to reside in countries
of high risk, as well as all health workers, vaccination is strongly
recommended. Vaccination should ideally begin 6 months before
travel.
Recommendations: CDC recommends vaccination for any of the following
people: any health care worker (medical, dental, or laboratory)
whose activities might result in blood exposure; any traveler
who may have intimate sexual contact with the local population;
any long-term (6 months or more)
traveler, e.g. teachers, who will reside in rural areas or have
daily physical contact with the local population; or any traveler
who is likely to seek either medical, dental, or other treatment
in local facilities during their stay. Hepatitis B vaccination
is not required for travel to any country.
OTHER DISEASES
SCHISTOSOMIASIS
Risk: In Tropical South America, schistosomiasis infection may
be found in parts of Brazil, Suriname, and Venezuela. For travelers
visiting these areas, the risk is a function of the frequency
and degree of contact with contaminated fresh water for bathing,
wading, or swimming.
Prevention: The traveler cannot distinguish between infested and
non-infested water. Therefore, swimming in fresh water in rural
areas should be avoided. Bath water should either be heated to
50 degrees C (122 degrees F) for five minutes or treated with
chlorine or iodine as done for drinking
water. If exposed, immediate and vigorous towel drying or application
of rubbing alcohol to the exposed areas may reduce the risk of
infection. Screening procedures are available for those who suspect
infection, and schistosomiasis is treatable with drugs.
Recommendations: Avoid contact with potentially contaminated water.
RABIES
Risk: For most countries in Tropical South America, there is a
risk of rabies infection particularly in rural areas, or in areas
where large numbers of dogs are found.
Prevention: Do not handle any animals! Any animal bite should
receive prompt attention. When wounds are thoroughly cleaned with
large amounts of soap and water, the risk of rabies infection
is reduced. Exposed individuals should receive prompt medical
attention and advice on post-exposure preventive treatment.
Recommendations: There are no requirements for vaccination, but
pre-exposure vaccination is recommended for:
- travelers visiting, for more than 30 days, foreign areas where
rabies is known to exist;
- veterinarians and animal handlers;
- spelunkers; and
- certain laboratory workers.
Pre-exposure vaccination does not nullify the need for post exposure
vaccine, but reduces the number of injections.
Recommendations for TROPICAL SOUTH AMERICA
Travelers should (1) take appropriate country specific malaria
prevention measures (chloroquine - in northern Argentina only),
(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
booster doses of tetanus (Td) and polio (eIPV) vaccines. (6) Depending
on the locations to be visited, planned activities, and health
of the traveler, the following vaccines should be considered:
Hepatitis B, Japanese Encephalitis, Typhoid, Rabies (pre-exposure),
and Cholera. (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.
Disease risks and precautions