ProMed Mail has a very interesting report of a possible case of Malaria in a Florida woman with no history of international travel. This could mean that malaria is occurring naturally in Florida. The species diagnosed is Plasmodium Falciparum which is known to be the most dangerous and drug resistant forms of malaria.
Fortunately, the woman is recovering well from the illness. Thus far for 2010 there have been 111 cases of malaria in Florida and all have acquired the parasitic infection in other countries. Locals are encouraged to be “on the lookout” for symptoms including fevers and muscle aches. Florida has been considered malaria free for many years due to aggressive mosquito control through spraying, habitat and breeding ground destruction and strong public health infrastructure. At present the case and how the woman acquired malaria is still under close investigation.
Here is a basic breakdown on malaria:
Malaria Basics: Parasitic infection of the red blood cells and liver that is acquired from the bite of an infected mosquito. Main symptoms include fatigue, muscle aches and a fever. Fever is known to undulate (come and go) approximately every 3 days. There are 4 main types: Plasmodium Vivax, Plasmodium Ovale, Plasmodium Malariae, and Plasmodium Falciparum.
Location: Most every tropical area of the world. P. Ovale is localized to West Africa. All other types are found worldwide.
Transmission: Transmitted by bite of infected Anopheles mosquito. Incubation period of 9-20 days, or longer.
Prevention: Avoiding outdoors at dawn and dusk (mosquito feeding times), long clothing to cover arms and legs, bed nets, permethrin treated clothing, DEET body spray, destroying mosquito breeding areas and anti-malaria medications.
Diagnosis: Blood smear that demonstrates Plasmodium species, try to draw blood during fevers.
Treatment: Based on species and sensitivity to medication. Chloroquine sensitive infections can be treated with quinine (600mg base initially then 300mg base at 6, 24 and 48 hours later) or with doxycycline for 7 days. Mefloquine (15mg/kg one time) is used for chloroquine resistant species. Multi-drug resistant strains can require artesunate.
Malaria Life Cycle:
First bite and liver stage: Humans get malaria by being bitten by a mosquito that is carrying malaria. The female mosquito carries malaria but does not get sick herself. She gets the malaria by biting another human that already has malaria. It is a vicious cycle. Once infected with malaria, the parasites travel to the person’s liver. There they begin to grow and mature within the cells of the liver. After a few days to months later, the parasites are ready to leave the liver. As they leave, they literally rupture the cells of liver.
Liver to the blood stream: From the liver the parasites migrate to the red blood cells (RBC). Once the parasites get into the red blood cells, they grow and mature some more. Then, you guessed it… They rupture out of the red blood cell (RBC). This causes the fever to appear to “come and go”. As the parasites are growing in the red blood cells there is no fever. Once they mature, they all rupture out of the RBCs together at the same time causing a fever. Once they leave the RBC the parasites infect other red blood cells. The cycle starts over again and the fever goes away. Once the new parasites mature in the red blood cells (after about 3-7 days), they rupture out and cause a fever. This goes on and on, over and over until treatment or death. If the person that carries malaria is bitten by a mosquito, the mosquito can carry the parasites to the next person they bite.
- Sickle Cell Trait (curved or sickled red blood cells) is believed to protect affected African-Americans from severe Plasmodium Falciparum infections
- Most Indigenous Africans have a natural resistance to Plasmodium Vivax due to am absence of Duffy Factor on their red blood cell surfaces
- The word “malaria” come from the two words “mal” and “aria” meaning bad air. This was because people first believed the disease was caused by bad air in the area. We know now that is it mosquitoes that transmit the disease.