Malaria

While the news has continued to focus on new developments in the Zika Virus, another, more-widespread virus, is utilizing mosquitos as a mode of transmission. Malaria is caused by Plasmodium parasites, and is transmitted to humans by the Anopheles mosquito. The life cycle of Plasmodium parasites occurs in both mosquitos and humans.

Malaria Lifecycle

Plasmodium life cycle  (CDC.gov)

When the parasite is brought to humans by the mosquito, the parasite infects and begins causing symptoms. In mosquitos, the parasite lives without affecting the host in a negative way. As seen in the map below, malaria is most commonly noticed in central Africa, parts of Asia, and some countries in South America. Malaria is also seen in less frequent amounts throughout central and eastern Asia, central America, and parts of Mexico. Children, pregnant women, those who have compromised immune systems, and those who have never traveled to a region with Malaria are most at risk to contract the disease.

Malaria Distribution

Distribution of malaria transmission rates throughout the world (CDC.gov)

 

Malaria usually presents 7-30 days after being bitten by an infected mosquito. Many times, malaria is treatable if diagnosed quickly. The primary symptoms include fever, sweats, headaches, chills, and vomiting. As the disease progresses, generally in the next 48 hours after symptoms are first observed, symptoms can worsen, including seizures, kidney failure, hypoglycemia, blood coagulation, and severe fevers. If not treated quickly, malaria can become fatal.

Fortunately, there are treatments available for those who are diagnosed with malaria, and many are effective if started quickly after diagnosis. Many drugs focus on killing the parasite that causes malaria. While these treatments exist in the United States and other developed countries however, they are not as accessible in many of the regions that are hit the hardest by malaria.

 

For more Information:

http://www.who.int/mediacentre/factsheets/fs094/en/

http://www.cdc.gov/malaria/index.html

The Problem with Under Reporting…

One of the most common problems noticed when a new disease emerges and the scientific community races to study it is the problem of under reporting. Under reporting in disease research can be seen at the case-reporting level (when local doctors incorrectly diagnose a disease and do not alert the proper authorities) or at a larger level, where whole countries do not properly understand and report the prevalence with a disease.

Under reporting can have serious consequences in infectious disease research because when scientists need to understand the severity of a disease, they will be unable to get an accurate and true picture. In the current Zika Virus outbreak in South America, one of the major problems being seen is the lack of accurate records as to the prevalence of microcephaly in children before the Zika outbreak. Scientists want to examine if there truly are more cases of microcephaly now than before, but the lack of records is proving to make the task difficult to complete.

Another example of where under reporting is proving to be a problem is in the study of Melioidosis, also known as Whitmore’s disease. Many people have never heard of this disease, (I haven’t heard of it before writing this post!!) but it is one of the most prevalent diseases spreading through many developing nations, such as India, Brazil, and other tropical areas. Melioidosis is caused by a shape-changing bacteria in contaminated soil and water, and it can infect both humans and animals. A new study, published in Nature Microbiology, estimates that this disease is under reported in 45 countries where it is known to exist, and is present in 34 more countries that do not report it yet. This is a serious problem because Melioidosis can be fatal within 48 hours of symptoms occurring. In these developing nations, where access to healthcare is limited and people live very close to one-another, this under reported disease can cause a serious problem in the future.