Before 1970 only 9 countries had experienced severe dengue epidemics. Today, however, the disease is endemic in more than 100 countries and the World Health Organisation estimates that between 50 – 100 million infections occur worldwide every year. The Americas, South-East Asia and Western Pacific regions are the most seriously affected. If you are travelling to countries where dengue is prevalent (or, live in a country affected by dengue) then it’s vital that you take precautions.
This article was written with assistance from Dr. Vineet Datta and International SOS
What is Dengue Fever?
Dengue fever is an infectious tropical disease transmitted by the female Aedes aegypti mosquito; this species prefers to live in or near human habitats and tend to bite during the day (as opposed to malaria, where these mosquitoes attack during the night). Dengue is also known as ‘break bone fever’ owing to the severe joint and muscle pain victims experience.
Who can catch dengue fever?
Map showing where dengue is most prevalent in the world
Dengue fever may occur in people of all ages who are exposed to infected mosquitoes. The disease is most prevalent in the Indian subcontinent, Southeast Asia, Southern China, Taiwan, the Pacific Islands, the Caribbean, Africa, Mexico, Central and South America. Mosquitos carrying dengue are mostly likely to be found in urban and semi-urban areas.
In many parts of the tropics and subtropics, dengue is endemic, that is, it occurs every year, usually during a season when Aedes mosquito populations are high, often when rainfall is optimal for breeding. These areas are, however, additionally at periodic risk for epidemic dengue, when large numbers of people become infected during a short period.
Average number of dengue cases reported to WHO.
What are the symptoms of Dengue Fever?
Dengue fever is a flu-like illness characterised by a fever that may last from two to seven day. Additional symptoms include headache, eye pain, muscle and joint pains and a skin rash. In extreme cases, the disease develops into the life-threatening dengue hemorrhagic fever.
How soon do the symptoms appear and how long do they last
Dengue fever may occur from three to 13 days after being bitten by an infected mosquito. Symptoms usually appear within four to seven days and usually pass within a couple of weeks. However, it can take several weeks to make a full recovery. It’s common to feel very tired in this recovery period.
There are 4 distinct strains of the virus, and recovery from infection by one provides lifelong immunity against that particular serotype. Cross-immunity to the other serotypes after recovery is only partial and temporary. Subsequent infections by other serotypes increase the risk of developing severe dengue.
Treating Dengue Fever
There is no specific treatment for dengue fever. As soon as dengue-like symptoms occur, you should see your doctor. These include: high fever, nausea, vomiting, pain behind the eyes, joints and muscles pain, severe headache.
Those diagnosed with dengue are advised to rest and drink plenty of fluids – plain water, unsweetened fruit juices or nutritious soups. Soft drinks should be avoided. Some people who have suffered from dengue have found that drinking raw papaya juice helps increase their blood platelet count. Although this isn’t scientifically proven, it is always worth a try. Pomegranate juice and Aloe-Vera juice are also believed by some to be effective.
Natural Foods for Helping Dengue
The following are some additional natural remedies that may help you recover from dengue fever:
- Squeeze half a lemon into a glass of fresh apple juice and drink 2-3 times a day.
- Squeeze fresh papaya leaves until juice appears and drink two tablespoons, 1 – 2 times a day (don’t boil the leaves first).
- Drink grapefruit juice 2-3 times a day
- Boil lemon grass in water and add honey.
- Black grapes, tomatoes, pomegranate, cherries and watermelon juices have strong antioxidant properties believe to help increase platelet levels.
- Carrot and cucumber juice is though to help patients dealing with the after-effects of dengue
How to Prevent Dengue Fever
There is no vaccine against dengue fever, although research is ongoing. Dengue, however, is preventable and steps can be taken to prevent being bitten.
The following list is aimed at both visitors travelling to, and families living in, countries that are at risk of dengue.
- Use Mosquito Repellent
One of the most effective ways of preventing dengue is using mosquito repellents on exposed skin. DEET, Picaridin, Oil of Lemon Eucalyptus and IR3535 are effective. Clothing can also be treated with repellent.
For kids Health Canada recommends that DEET-based products be used on children between the ages of 2 and 12 only if the concentration of DEET is 10% or less and that repellents be applied no more than 3 times a day. Children under the age of 2 should not receive more than 1 application of repellent in a day. Generally, the duration of protection varies with the DEET concentration: higher concentrations protect longer. Do not apply repellent to kids’ hands so there is no chance of them ingesting it or rubbing and irritating their eyes. Oil of lemon eucalyptus is not recommended for kids under 3 years old.
Children should sleep in rooms with air conditioning or screened windows or sleep under bed nets, when available. Mosquito netting should be used over infant carriers. Children can reduce skin exposed to mosquitoes by wearing long pants and long sleeves while outdoors in areas where malaria is transmitted.
The following are some mosquito repellents we have used and found effective:
Mosquito patches & coil
- Mosquito patches These citronella-infused stickers can be stuck on the backs of kids’ clothing. The better quality ones can be reused (lasting for up to 3 days). Non-toxic, DEET-free and no skin contact.
- Odomos Available in India and other areas of the Indian Subcontinent, is this highly effective and clinically proven mosquito repellent that is safe for kids.
- Mosquito Repellent Bands Many of these citronella-infused silicone wristbands are long-lasting and waterproof. These are a good option for older kids (younger children might try and eat them!).
- Mosquito Wipes Like wet wipes these are easy to use and particularly good for little kids. Various brands are available; we’ve tried the DEET-free Pigeon anti-mosquito wet wipes and found them to be effective.
- Wear Protective Clothing
Cover as much of your skin as possible. Wear long sleeves, long pants / trousers, socks and covered shoes. Light coloured clothing is less attractive to mosquitoes than dark colours.
- Avoid mosquito-attracting smells
Perfume and sweat attract mosquitos like bees to pollen; shower to remove sweat and use unscented sunscreen and shampoos.
- Use mosquito deterrents in the home
Add a drop of citronella oil or lemon grass to the water you mop your floors with
- Numerous electronic vaporiser repellents for keeping mosquitoes at bay are available but it is important to remember that the fumes inhaled by kids might cause allergic reactions. You can also use mosquito repellents, which are either applied on the body or in contact with the skin. Various other alternatives available in India include Citronella Balm, Odomos Naturals, anti-mosquito wipes etc. These should be used in addition to long sleeve clothing as well as use of mosquito nets.
- Marigolds and lemon grass are natural insect repellents and can be planted around your house and garden. Add a drop of citronella oil or lemon grass to the water you mop your floors with.
- Use an insecticide-treated bed net. Make sure the net does not have any tears. Tuck the ends in under the mattress, or make sure it reaches the floor.
- When inside, use air conditioning if available.
- Make sure window and door screens are secure and free of holes.
- Homemade remedies such as cloves stuck into oranges or lemons may help to repel mosquitos – and flies!
Orange with cloves
- Avoid breeding grounds
Favourite breeding grounds of mosquitoes
Mosquitoes are more likely to be found in areas where they can breed, such as stagnant pools. Make sure there are no unnecessary collections of water in your home (e.g in paddling pools, old tyres, pot plant dishes, etc.)
- ‘Invisibility Cloak‘
Less Harry Potter and more a possible lifesaver for mosquito-plagued people are these ‘cloaks’ developed by US Scientists to block mosquitos’ ability to smell and target their victims. See more here.