Mosquito-Borne Diseases from Travel

Is this your child's symptom?

  • Tropical diseases spread by mosquitoes
  • Includes malaria, yellow fever, dengue fever, chikungunya fever and Zika virus
  • Your child has no symptoms of tropical disease. If your child has symptoms, use other guides. These diseases start with high fevers.
  • Tropical diseases occur in people who travel to or live in high-risk countries. These mainly are developing countries near the Equator. You may have traveled to a high-risk country recently.
  • West Nile Virus is not included in this guide. See the Mosquito Bite guide.

How Tropical Mosquito-Borne Diseases are Detected by this Symptom Checker

  • These diseases can't be diagnosed over the phone. But, they can be suspected based on their symptoms. They are then referred to a medical setting where a diagnosis can be made.
  • Malaria will be picked up by the Fever guide. High fevers, prolonged fever and shaking chills will refer the child to be seen. The Headache or Leg Pain guides will also work. Reason: Malaria can also cause severe headache or muscle pain.
  • Yellow fever will be picked up by the Fever guide. High fevers, prolonged fever and shaking chills will refer the child to be seen. The Headache or Leg Pain guides will also work. Reason: Yellow fever can also cause severe headache or muscle pains.
  • Dengue fever will be picked up by the Fever guide. High fevers, prolonged fever and shaking chills will refer the child to be seen. The Headache or Leg Pain guides will also work. Reason: Dengue fever can also cause severe headache, joint pain or muscle pains.
  • Chikungunya fever will be picked up by the Fever guide. High fevers, prolonged fever and shaking chills will refer the child to be seen. The Arm Pain or Leg Pain guides will also work. Reason: Joint pains in the hands and feet are common. So are muscle pains.
  • Zika virus infection will be picked up by the Fever or Rash care guides.
  • Travel to a high risk country should raise the concern. However, common diseases that cause fever (such as colds) also must be ruled out. They occur more commonly in these countries than the serious diseases. But, severe symptoms or symptoms that last too long make us think about these other diseases.

World-wide Causes of Death in Children Under Age 5

  • 6.3 million children under the age of 5 died in 2013 worldwide.
  • These 5 infections account for over 50% of all early child deaths:
    1. Pneumonia and other respiratory diseases 19%
    2. Diarrhea disease 18%
    3. Malaria 8%
    4. Measles 4%
    5. HIV/AIDS 3%
  • Poor nutrition is a factor in over half who die older than one month of age.
  • Over 80% of deaths occur in Africa and Southern Asia. India accounts for 21% of under-five deaths.
  • More than half are due to diseases that we could prevent or treat.
  • Resource: WHO report, September 2014

Tropical Countries

  • Countries in the tropics are near the Equator. They have hot and humid climates.
  • The tropics are also defined as regions without a cold season.
  • Many diseases in these countries are spread by an insect bite.
  • In the tropics, insects never hibernate. They are present in large numbers year round.
  • Other diseases here are spread by germs that multiply in warm water. The water in the tropics usually stays warm.
  • Tropical diseases occur in people who live in or travel to high-risk countries.
  • Climate change is a factor that has allowed these diseases to spread.

Preventing Mosquito Bites During Travel

  • Wear long pants, a long-sleeved short and a hat.
  • Avoid being outside when the bugs are most active. Mosquitoes are most active at dawn and dusk. Limit your child's outdoor play at these times. The mosquito that transmits Zika is also active during the day.
  • Get rid of any standing water. Reason: it's where mosquitoes lay their eggs.
  • Keep bugs out of the home by fixing any broken screens.
  • If exposed to outside air, use bed nets to protect you during sleep.
  • To prevent mosquito bites, use insect repellents that have DEET. These products work well to protect you from bites. Read the label before using.

Preventing Bites - Use DEET on Skin and Permethrin on Clothing

  • DEET is a good mosquito repellent. It also repels ticks and other bugs.
  • The AAP approves DEET use for children more than 2 months old. Use 30% DEET or less. Use 30% DEET if you need 6 hours of protection. Use 10% DEET if you only need protection for 2 hours.
  • Don't put DEET on the hands if your child sucks their thumb or fingers. Reason: prevent DEET from being swallowed.
  • Warn older children who apply their own DEET to use less. A total of 3 or 4 drops can protect the whole body.
  • Put on exposed areas of skin. Do not use near eyes or mouth. Don't use on skin that is covered by clothing. Don't put DEET on sunburns or rashes. Reason: DEET can be easily absorbed in these areas.
  • Wash it off with soap and water when your child comes indoors.
  • Caution: DEET can harm clothing made of man-made fibers. It can also harm plastics (eye glasses) and leather. DEET can be used on cotton clothing.
  • Permethrin products can be applied to all types of clothing.
  • See Mosquito Bite care guide for more info on how to prevent bites.

When to Call for Mosquito-Borne Diseases from Travel

Call 911 Now

  • You think your child has a life-threatening emergency

Call Doctor or Seek Care Now

  • Tropical disease suspected and fever present
  • Tropical disease has been diagnosed and getting worse
  • Tropical disease has been diagnosed and fever returns after gone for several days
  • Tropical disease has been diagnosed and shaking chills return
  • Your child looks or acts very sick
  • You think your child needs to be seen, and the problem is urgent

Contact Doctor Within 24 Hours

  • Tropical disease suspected, but no fever
  • You think your child needs to be seen, but the problem is not urgent

Contact Doctor During Office Hours

  • Pregnant and recently traveled to or lives in a place with a Zika outbreak
  • You have other questions or concerns

Self Care at Home

  • Questions about malaria
  • Questions about yellow fever
  • Questions about dengue fever
  • Questions about Chikungunya fever
  • Questions about Zika virus

Seattle Children's Urgent Care Locations

If your child’s illness or injury is life-threatening, call 911.

Care Advice

Malaria Questions

  1. What You Should Know About Malaria:
    • It is a parasite disease spread by the bite of mosquitoes. The parasites enter red blood cells and destroy them.
    • World Impact: There are over 200 million new cases per year. It is a leading cause of death in the world. In Africa, one child dies every minute from it. It causes almost 1 million deaths per year.
  2. Symptoms:
    • Bouts of high fever occur every 2 to 3 days.
    • Shaking chills come before the fever.
    • The fever is followed by profuse sweating.
    • Severe headache, muscle pains and feeling very tired is common.
    • Sometimes, jaundice (yellow skin) occurs.
  3. Cause:
    • Malaria is caused by a tiny parasite (protozoan) carried by some mosquitoes.
    • Spread is mosquito to human.
    • The disease is carried by an infected mosquito. The mosquito becomes infected when it bites a human infected with malaria. The parasite is then passed on to healthy humans in the spit from a bite. It then enters the person's red blood cells.
  4. Time Period to Get Sick:
    • The time from the bite to symptoms is 5-15 days.
  5. Contagious Period:
    • Person to person spread of the illness does not occur.
    • Kissing or sharing a glass with a person who has malaria is safe.
  6. Tests and Treatment:
    • Blood smears and other blood tests are done to diagnose it.
    • It is treated with anti-malaria drugs.
    • For severe symptoms, patients will need care in a hospital.
  7. What to Expect:
    • Patients have good outcomes if treated early.
    • Deaths are highest in infants: up to 3%.
  8. How to Prevent:
    • Use insect repellents (such as DEET).
    • Bed nets can help protect you at night during sleep.
    • Malaria drugs are often prescribed before travel to a high risk zone.
    • There is no vaccine to prevent it.
  9. Countries with Malaria:
    • It occurs in Africa, lower Asia, Central and South America. Over 90% of cases occur in Africa.
    • It does not occur in the US except in travelers coming back. This results in about 1500 US cases per year.
    • For more info and for current high-risk countries, see the CDC website: Malaria.
  10. Call Your Doctor If:
    • You have other questions or concerns

Yellow Fever Questions

  1. What You Should Know About Yellow Fever:
    • It is viral disease spread by the bite of mosquitoes. The virus attacks the liver and kidneys.
    • World Impact: Africa has 200,000 new cases each year. There are over 30,000 deaths each year. Now, it is rare in travelers because of the yellow fever vaccine.
  2. Symptoms:
    • High fevers with shaking chills occur.
    • Other symptoms are severe headache, backache and muscle pains.
    • Jaundice (yellow skin) is common. Hence, the name yellow fever.
    • If the disease progresses, bleeding from the skin, nose, gums and gut will occur.
  3. Cause:
    • Spread is mosquito to human.
    • The virus is carried by an infected mosquito. The mosquito becomes infected when it bites a human infected with yellow fever. The virus is passed on to healthy humans in spit from a bite.
  4. Time Period to Get Sick:
    • The time from the bite to symptoms is 3-6 days.
  5. Contagious Period:
    • Person to person spread of the illness does not occur.
    • Kissing or sharing a glass with a person who has yellow fever is safe.
  6. Tests and Treatment:
    • Blood tests are needed to diagnose it.
    • Patients need care in a hospital.
    • There are no anti-viral drugs for treating it.
  7. What to Expect:
    • The death rate in people with complications can be high.
  8. How to Prevent:
    • Vaccine: There is a yellow fever vaccine to prevent the illness.
    • Use insect repellents (such as DEET).
    • Bed nets can help protect you at night during sleep.
  9. Countries with Yellow Fever:
    • Mostly occurs in Africa.
    • Less common in South America (100 cases per year). Reason: Wide use of the vaccine.
    • It does not occur in the US except in travelers coming back.
    • For more info and for current high-risk countries, see the CDC website: Yellow Fever.
  10. Call Your Doctor If:
    • You have other questions or concerns

Dengue Fever Questions

  1. What You Should Know About Dengue Fever:
    • It is a viral disease spread by the bite of an infected mosquito.
    • World Impact: 90 million new infections each year in the world. It causes 20,000 deaths per year.
  2. Symptoms:
    • High fever with shaking chills occurs.
    • Patients can also have severe headache, eye pain, joint pain and muscle pains.
    • Bone pain can be severe.
    • A widespread pink rash is common.
    • If the disease progresses, bleeding from the skin, nose, gums and gut can occur.
  3. Cause:
    • Spread is mosquito to human.
    • The virus is carried by an infected mosquito. The mosquito becomes infected when it bites a human infected with dengue. The virus is passed on to healthy humans in spit from a bite.
  4. Time Period to Get Sick:
    • The time from the bite to symptoms is usually 3-7 days. Sometimes, it can be up to 14 days.
  5. Contagious Period:
    • Person to person spread of the illness does not occur.
    • Kissing or sharing a glass with a person who has dengue is safe.
  6. Tests and Treatment:
    • Blood tests are needed for people with severe disease.
    • Treatment consists of rest and lots of fluids.
    • For severe symptoms, patients need care in a hospital.
    • There are no anti-viral drugs for treating it.
  7. What to Expect:
    • Fever lasts up to 7 days.
    • Symptoms last up to 2 weeks.
    • Most people recover fully.
    • If bleeding occurs, the death rate can be 1%.
  8. How to Prevent:
    • Use insect repellents (such as DEET).
    • Bed nets can help protect you at night during sleep.
    • There is no vaccine to prevent it.
  9. Countries with Dengue Fever:
    • It occurs in Asia, Africa, South America and the Caribbean islands.
    • It does not occur in the US except in travelers coming back. A few cases have occurred in Florida and Texas.
    • For more info and for current high-risk countries, see the CDC website: Dengue.
  10. Call Your Doctor If:
    • You have other questions or concerns

Chikungunya Fever Questions

  1. What You Should Know About Chikungunya Fever:
    • It is a viral disease spread by the bite of an infected mosquito.
    • World Impact: It is a common disease, but rarely any deaths.
  2. Symptoms:
    • Most common symptoms are fever and joint pain.
    • The joint pain starts in the hands and feet.
    • This can progress to swollen joints.
    • Other symptoms are headache and muscle pains.
    • A widespread pink rash may occur.
  3. Cause:
    • Spread is mosquito to human.
    • The virus is carried by an infected mosquito. The mosquito becomes infected when it bites a human infected with Chikungunya. The virus is passed on to healthy humans in spit from a bite.
  4. Time Period to Get Sick:
    • The time from the bite to symptoms is 3-7 days.
  5. Contagious Period:
    • Person to person spread of the illness does not occur.
    • Kissing or sharing a glass with a person who has chikungunya is safe.
  6. Tests and Treatment:
    • Blood tests are done for people with severe disease.
    • Treatment is mainly rest and lots of fluids.
    • Medicines are given for pain and fever.
    • For severe symptoms, patients will need care in a hospital.
    • There are no anti-viral drugs for treating it.
  7. What to Expect:
    • Most symptoms are gone within a week.
    • In some people, the joint pain can last for months.
    • Deaths are very rare.
  8. How to Prevent:
    • Use insect repellents (such as DEET).
    • Bed nets can help protect you at night during sleep.
    • There is no vaccine to prevent it.
  9. Countries with Chikungunya:
    • It is common in Africa and Asia.
    • In 2013, the disease was first reported in the Caribbean islands.
    • It then spread to Central and South America.
    • Does not occur in the US except in travelers coming back.
    • No signs of the disease yet in US mosquitoes.
    • For more info and current high-risk countries, see the CDC website: Chikungunya Virus.
  10. Call Your Doctor If:
    • You have other questions or concerns

Zika Virus Questions

  1. What You Should Know About Zika Virus:
    • Zika is a viral disease spread by the bite of mosquitoes.
    • A major outbreak was reported in Brazil in May 2015. It then spread through the Americas and the Caribbean.
  2. Zika Virus Symptoms:
    • 80% of infections have no clinical symptoms.
    • Mild illness: 20% of infections. Symptoms include fever, pink rash, joint pains, headache, body aches and red eyes. These symptoms last 3 to 6 days and go away without any treatment. Severe symptoms are not common.
  3. Birth Defects and Zika Virus:
    • A pregnant woman who gets a Zika infection can pass the virus to her baby. The baby may develop a severe birth defect called microcephaly. It causes babies to be born with a small head and brain damage. Eye defects have also been reported.
    • The risk of microcephaly is 1-5% depending on the time of pregnancy. The first 3 months of pregnancy carries the greatest risk of causing this birth defect.
    • Pregnant women who get Zika within 2 weeks of delivery can pass it to the newborn. The newborn will be ill, but not have birth defects.
    • Babies who get Zika from a bite have the same mild symptoms as others. They cannot develop microcephaly after they are born.
  4. Cause:
    • Spread is usually from mosquito to human.
    • The virus is carried by an infected mosquito. The mosquito becomes infected when it bites a human infected with Zika. The virus is passed on to healthy humans in spit from a bite.
    • Pregnant women can pass the virus to their baby.
    • Breastfeeding: it is not passed in breastmilk. Continue to breastfeed (CDC).
    • Sexual intercourse: it can be transmitted through sex. If their partner is pregnant, males who have been in high-risk areas should use condoms. Use these until the baby is delivered. If a man or woman travels to a Zika risk area, use condoms. Avoid pregnancy for 8 weeks.
  5. Time Period to Get Sick:
    • The time from the bite to symptoms is 3 days to 2 weeks.
  6. Tests and Treatment:
    • Blood tests are needed to diagnose Zika virus.
    • When do you need to get a blood test? Any pregnant woman who has recently traveled to or lives in a high-risk area for Zika virus. See CDC website. Blood tests are mainly available at CDC and some state public health labs. If you need a blood test, talk to your obstetrician (OB doctor).
    • There are no anti-viral drugs for treating it. Treat the symptoms with increased fluids and pain medicine.
  7. What to Expect:
    • If symptoms occur, they usually last less than 1 week.
  8. How to Prevent:
    • Use insect repellents such as DEET.
    • Bed nets can help protect you at night during sleep.
    • There is no vaccine to prevent it.
  9. Countries with Zika Virus:
    • Current outbreak South America, Central America, Mexico and the Caribbean. Also in isolated areas of Africa and Asia.
    • Until July 2016, mosquito transfer of Zika virus in the US did not occur. The disease only occurred in travelers coming back into the US. In 2016, there were more than 4,000 US cases associated with travel to high-risk countries.
    • In August 2016, a small outbreak transmitted by local mosquitoes began in Florida. Predictions are that it will eventually occur in several southern US states.
    • For up-to-date information and current high-risk areas, see the CDC website: Zika Virus.
  10. Call Your Doctor If:
    • You have other questions or concerns

And remember, contact your doctor if your child develops any of the 'Call Your Doctor' symptoms.

Disclaimer: this health information is for educational purposes only. You, the reader, assume full responsibility for how you choose to use it.

Last Reviewed: 10/11/2023

Last Revised: 12/30/2022

Copyright 2000-2023. Schmitt Pediatric Guidelines LLC.