MyMD Miami’s Insights and Awarenes Local Malaria Cases
Eight homegrown Malaria cases found in the United States – the first in over 20 years!
Hello my name is Dr. Robert Freedman. I am an Internal Medicine specialist with a subspecialty in Infectious Diseases. I would like to talk to you today about Malaria, which has been in the news recently because of eight cases that were reported in Florida and Texas – the first homegrown Malaria cases contracted in the United States in twenty years.
The reason for concern and why these cases are newsworthy is because Malaria is not commonly seen in the United States. Normally, whenever we diagnose somebody with Malaria here, it is because the infected person had traveled to an endemic region like Sub-Saharan Africa, Haiti, India, or Southeast Asia – countries that are known to have areas where Malaria is seen. But, the recent eight cases are considered “home grown” because none of the eight patients who contracted Malaria gave a history of ever traveling to any place where Malaria is prevalent. Therefore, the assumption is they became infected here.
Malaria is a potentially deadly parasitic disease transmitted by the female Anopheles mosquito. No other mosquito can transmit malaria. It cannot be transmitted from human to human unless the Anopheles mosquito bit a human that was already infected with Malaria, and then bit another person. Or another way would be if two people were using IV drugs, one of them had an active case of Malaria, and they were sharing needles.
Symptoms of Malaria are nonspecific, meaning there is nothing that specifically makes one think of Malaria since many other illnesses, such as the flu, can cause these same symptoms. They include fever, chills, malaise, sweating, headache, cough, loss of appetite, nausea, vomiting, abdominal pain, diarrhea, joint pains, and muscle aches. These symptoms should be taken seriously, as Malaria can quickly become severe and in some cases, fatal.
The most common Malaria species are Vivax, Ovale, Falciparum, and Malariae. Of the four species, the most dangerous is Falciparum. This is because it has the highest degree of parasitemia (the number of parasites that enter the bloodstream) and it demonstrates drug resistance to some of the more commonly used medications.
The species that was isolated in Sarasota County, Florida and Cameron County, Texas however was Vivax. Treatment of uncomplicated non-falciparum Malaria (like Vivax or Ovale) is usually with chloroquine to kill the parasite in the blood, followed by a medication called primaquine, to kill the parasites in the liver.
But while Vivax is a less deadly parasite than Falciparum, it can remain dormant, hiding in cysts in the liver and possibly causing infections many years after the original onset of the illness. When the cysts in the liver phase rupture, they release the parasite into the bloodstream. People become ill with malaria and become symptomatic at this time, when the parasite enters the bloodstream. This explains what is known as relapsing Malaria and is why the incubation period for vivax can be long and extend to months or years; and why after treating vivax with chloroquine, you then must use primaquine to kill any potential liver cysts to prevent relapsing malaria.
Therefore, if you have traveled to an endemic area and develop these symptoms, you should see your doctor and give him/her the history of your travel. This will allow your doctor to include Malaria as a possible differential diagnosis for your symptoms and the doctor will order a thick and thin blood smear looking for malaria.
If you live in or near any of the areas where these recent cases of Malaria have surfaced, and you have symptoms, don’t assume your symptoms are just a flu like illness or other virus. See your doctor and check it out.