Malaria and Mosquito Repellents

Malaria and Mosquito Repellents

Prevention against mosquito bites is of prime importance, irrespective of whether prophylaxis is taken or not.

Such protective measures are:

• Sleeping in properly screened rooms and using a knockdown fly spray to kill any mosquitoes that may have entered the room during the day.
• If sleeping in a non-air-conditioned room, using mosquito nets around the bed, checking that there are no holes, and tucking the edges under the mattress before nightfall. Protection may be nhanced by soaking the net in permethrin, 0.2 g/m2 of material every six months.
• Using an electric mat to vaporize synthetic pyrethroids overnight or burning mosquito coils.
• Wearing long sleeved clothing and long trousers when out of doors after sunset and avoiding dark colours.
• Using repellents that contain N.N. diethylmetatoluamide (DEET), an ingredient present in many commercially available insect repellents. The actual concentration of DEET varies among repellents, ranging up to 95%. Some persons exposed to DEET have had potentially serious toxic encephalopathy. The possibility of adverse reactions to DEET will be minimized if the following precautions are taken: apply repellent sparingly only to exposed skin or clothing; avoid applying high-concentration products to the skin, particularly of children; do not inhale or ingest repellents or get them into the eyes; avoid applying repellents to portions of children’s hands that are likely to have contact with eyes or mouth; never use repellents on wounds or irritated skin; wash repellent treated skin after coming indoors; and if a suspected reaction to insect repellent occurs, wash treated skin and seek medical attention.
• Several new and safe low-dose DEET preparations may be available in your area (Repel, Ultrathon, Cutters, etc, along with a repellent known as Mosiguard made from a blend of Eucalyptus oils). These come in the form of spray, stick or gel. The June 2000 issue of Consumer Reports, a US consumer goods publication, has a nice summary on these products.
• When using sunscreen cream and mosquito repellent, use either one of the new combined products or applies the mosquito repellent approximately 30 minutes before the sunscreen lotion.
• Not relying on electronic buzzers, which are ineffective.

Malaria Prophylaxis

Your second line of defense in malaria areas, after protection from mosquito bites, is the use of medications to prevent malaria development in your body.

Obviously these pills cannot keep you from being bitten. Because malaria develops as an infection over several weeks it is absolutely critical that any pills be continued for the prescribed period (usually 4 weeks) after you leave the malaria area.

Recommendations for prophylactic tablets vary among various authorities (WHO, CDC, etc), in part because changing patterns of disease incidence and resistance to medication are constantly under study. Further, local advice may differ from what is printed in books or on websites, as local knowledge is more precise.

Medication used for prophylaxis is usually one of the following:

Mefloquine: 

Frequency:

• Once per week with a large meal.
• Start 1 week before, continue 4 weeks after.
• Usual adult dose is one 250 mg tablet.
• Children’s doses vary with age, height.

Potential Side Effects:

• Nausea, dizziness, sweating
• Seizures in those prone
• Depression or psychosis rarely
• Cannot be used in pregnancy

Chloroquine 250 mg alone or with Paludrine 100 mg

Frequency:

• Chloroquine – 2 tablets, weekly with food
• Paludrine – one daily (these doses must be adjusted in children, and are taken 1 week before and 4 weeks after exposure.

Potential Side Effects:

• Chloroquine – nausea, dizziness.
• Long-term may affect liver.
• Paludrine – nausea, headache.
• Both are safe in pregnancy

Doxycycline 100 mg

Frequency:

One daily with food. 3 days before, and 4 weeks after exposure. NOT for children under age 8.

Potential Side Effects:

• Abdominal pain
• Skin rash with sun exposure in some
• Cannot be used in pregnancy

Malarone

Frequency:

One tablet daily. One day before, and one week after exposure. Pediatric formulation available.