Medications similar to those used to cure malaria can prevent it if taken before, during, and after your trip. It's vital to take your medication as prescribed, even after you return home.
Before travelling, check with your doctor or travel clinic about the region's malaria status. Risk of infection also depends on:. Since mosquitoes are night feeders, stay away from danger zones — particularly fields, forests, and swamps — from dusk to dawn to avoid being bitten. Use permethrin-treated mosquito netting when sleeping, and place screens on doors and windows. Using mosquito coils and aerosolized insecticides containing pyrethroids may also help improve protection during this time.
Wear long sleeves and pants, and light-coloured clothing. Put mosquito repellent containing DEET on exposed skin. Do not apply more than 3 times a day on children 2 to 12 years old. DEET and sunscreen can be safely worn at the same time.
Apply the sunscreen first, wait 20 minutes, and then apply DEET. Be sure to wash your hands after application. All material copyright MediResource Inc. Terms and conditions of use.
The contents herein are for informational purposes only. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Source: www. Conditions A-Z M Malaria.
Malaria Tropical Diseases, Parasitic Infection. About this Condition. The Facts Malaria is a mosquito-borne parasitic infection spread by Anopheles mosquitoes. Acne Doctor Discussion Guide. Overview Malaria is a disease caused by a parasite. Request an Appointment at Mayo Clinic. Malaria transmission cycle Open pop-up dialog box Close. Malaria transmission cycle Malaria spreads when a mosquito becomes infected with the disease after biting an infected person, and the infected mosquito then bites a noninfected person.
Share on: Facebook Twitter. Show references AskMayoExpert. Mayo Clinic; Jameson JL, et al. In: Harrison's Principles of Internal Medicine. New York, N. Accessed Oct. Bennett JE, et al. Malaria plasmodium species. Elsevier; Accessed Dec. Merck Manual Professional Version. Brunette GW, et al. Oxford University Press; Breman JG. Clinical manifestations of malaria in nonpregnant adults and children. Daily J. Treatment of uncomplicated falciparum malaria in nonpregnant adults and children.
Malaria transmission has been eliminated in many countries of the world, including the United States. However, in many of these countries including the United States Anopheles mosquitoes are still present. Thus the potential for reintroduction of active transmission of malaria exists in many non-endemic parts of the world. All patients must be diagnosed and treated promptly for their own benefit but also to prevent the reintroduction of malaria. Biologic characteristics present from birth can protect against certain types of malaria.
Two genetic factors, both associated with human red blood cells, have been shown to be epidemiologically important. Persons who have the sickle cell trait heterozygotes for the abnormal hemoglobin gene HbS are relatively protected against P. Because P. In general, the prevalence of hemoglobin-related disorders and other blood cell dyscrasias, such as Hemoglobin C, the thalassemias and G6PD deficiency, are more prevalent in malaria endemic areas and are thought to provide protection from malarial disease.
Persons who are negative for the Duffy blood group have red blood cells that are resistant to infection by P. Since the majority of Africans are Duffy negative, P. In that area, the niche of P. Other genetic factors related to red blood cells also influence malaria, but to a lesser extent. More on: Sickle Cell and Malaria. Acquired immunity greatly influences how malaria affects an individual and a community.
After repeated attacks of malaria a person may develop a partially protective immunity. In areas with high P. As these antibodies decrease with time, these young children become vulnerable to disease and death by malaria.
If they survive repeated infections to an older age years they will have reached a protective semi-immune status. Thus in high transmission areas, young children are a major risk group and are targeted preferentially by malaria control interventions. In areas with lower transmission such as Asia and Latin America , infections are less frequent and a larger proportion of the older children and adults have no protective immunity.
In such areas, malaria disease can be found in all age groups, and epidemics can occur. Anemia in young children in Asembo Bay, a highly endemic area in western Kenya. Anemia occurs most between the ages of 6 and 24 months.
After 24 months, it decreases because the children have built up their acquired immunity against malaria and its consequence, anemia. The mother had malaria, with infection of the placenta.
Pregnancy decreases immunity against many infectious diseases. Women who have developed protective immunity against P. Malaria during pregnancy is harmful not only to the mothers but also to the unborn children. The latter are at greater risk of being delivered prematurely or with low birth weight, with consequently decreased chances of survival during the early months of life. For this reason pregnant women are also targeted in addition to young children for protection by malaria control programs in endemic countries.
More on: Malaria During Pregnancy. Human behavior, often dictated by social and economic reasons, can influence the risk of malaria for individuals and communities. For example:. Human behavior in endemic countries also determines in part how successful malaria control activities will be in their efforts to decrease transmission. The governments of malaria-endemic countries often lack financial resources.
As a consequence, health workers in the public sector are often underpaid and overworked. They lack equipment, drugs, training, and supervision. The local populations are aware of such situations when they occur, and cease relying on the public sector health facilities.
Conversely, the private sector suffers from its own problems. Regulatory measures often do not exist or are not enforced. This encourages private consultations by unlicensed, costly health providers, and the anarchic prescription and sale of drugs some of which are counterfeit products. Correcting this situation is a tremendous challenge that must be addressed if malaria control and ultimately elimination is to be successful.
The sickle cell gene is caused by a single amino acid mutation valine instead of glutamate at the 6th position in the beta chain of the hemoglobin gene. Inheritance of this mutated gene from both parents leads to sickle cell disease and people with this disease have shorter life expectancy. On the contrary, individuals who are carriers for the sickle cell disease with one sickle gene and one normal hemoglobin gene, also known as sickle cell trait have some protective advantage against malaria.
As a result, the frequencies of sickle cell carriers are high in malaria-endemic areas. Most of this protection occurs between months of life, before the onset of clinical immunity in areas with intense transmission of malaria. Those who had the sickle cell trait HbAS had a slight survival advantage over those without any sickle cell genes HbAA , with children with sickle cell disease HbSS faring the worst. Lancet ; Malaria is transmitted to humans by female mosquitoes of the genus Anopheles.
Female mosquitoes take blood meals for egg production, and these blood meals are the link between the human and the mosquito hosts in the parasite life cycle. In contrast to the human host, the mosquito host does not suffer noticeably from the presence of the parasites. Map of the world showing the distribution of predominant malaria vectors.
Anopheles freeborni mosquito pumping blood Larger Picture. Sequential images of the mosquito taking its blood meal. There are approximately 3, species of mosquitoes grouped into 41 genera. Human malaria is transmitted only by females of the genus Anopheles. Of the approximately Anopheles species, only transmit malaria i. The rest either bite humans infrequently or cannot sustain development of malaria parasites. Anophelines are found worldwide except Antarctica. Malaria is transmitted by different Anopheles species in different geographic regions.
Within geographic regions, different environments support a different species. Anophelines that can transmit malaria are found not only in malaria-endemic areas, but also in areas where malaria has been eliminated. These areas are thus at risk of re-introduction of the disease. Like all mosquitoes, anopheles mosquitoes go through four stages in their life cycle: egg, larva, pupa, and adult. The first three stages are aquatic and last days, depending on the species and the ambient temperature.
The biting female Anopheles mosquito may carry malaria. Male mosquitoes do not bite so cannot transmit malaria or other diseases. The adult females are generally short-lived, with only a small proportion living long enough more than 10 days in tropical regions to transmit malaria. Adult females lay eggs per oviposition.
Eggs are laid singly directly on water and are unique in having floats on either side. Eggs are not resistant to drying and hatch within days, although hatching may take up to weeks in colder climates.
Mosquito larvae have a well-developed head with mouth brushes used for feeding, a large thorax, and a segmented abdomen. They have no legs. In contrast to other mosquitoes, Anopheles larvae lack a respiratory siphon and for this reason position themselves so that their body is parallel to the surface of the water. Top: Anopheles Egg; note the lateral floats. Bottom: Anopheles eggs are laid singly. Larvae breathe through spiracles located on the 8th abdominal segment and therefore must come to the surface frequently.
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