Tuesday, February 9, 2010

Natural Immunity to Ebola- Olivia Cvitanic

A recent study conducted in rural Gabon has concluded that there may be some natural immunity people have acquired to combat Zaire ebolavirus (ZEBOV) in areas where the disease is especially prevalent. The researchers tested 4,349 people from 220 randomly selected villages in Gabon using the ELISA method. Out of the people tested, 15.3 % tested positive for ZEBOV. This figure increased to almost 20% in especially forested areas. Individuals were tested using the Western blot which determined whether an individual had anti-ZEBOV IgG. IgG is an immunoglobin. Immunoglobins are proteins that make up antibodies. Also, researchers studied individuals’ CD8 T cells and tested for an antibody response upon “ZEBOV stimulation.” The results indicate that a significant portion of the population living in very rural areas of Gabon “have both humoral and cellular immunity to ZEBOV.” One theory as to why people in these rural areas exhibit higher levels of immunity suggests that many of the tropical fruits growing in rural Gabon have been contaminated by bat saliva. Fruit bats have been known to spread the disease so this theory is possible. While Ebola is not a serious problem in the United States, there are serious outbreaks that occur in Africa. In order to prevent future outbreaks or even eradicate the disease completely in Africa, is it possible to use these ZEBOV immune people’s blood serum in the same way it was done with Lassa virus? In The Coming Plague, a missionary nurse, Ms. Pinneo, survived Lassa fever and anti- Lassa antibodies were present in her blood afterwards, though she suffered debilitating effects from the disease later on. Since, in the case of Ebola, there are only two strains Ebola-Zaire and Ebola-Sudan, I don’t see why a vaccine could not be developed to prevent future outbreaks or at least “a serum” to help treat infected persons as was used to treat a researcher infected with Lassa fever in The Coming Plague. To be honest, this article was a little difficult for me to understand because of all the medical and biological jargon; however, the presence of Ebola immunity was news to me and I thought deserved attention. Many of the terms such as seroprevalence and IgG I had to look up on my own. If you would like to read more, here’s the link:http://www.flutrackers.com/forum/showthread.php?t=140894

1 comment:

Anonymous said...

There are actually 5 species of Ebola virus, namely Zaire, Sudan, Cote d'Ivoire, Bundibugyo and the putative non pathogenic to humans Reston ebolavirus. Several isolates for each species have been so far identified.
Beyond the theoretical naturally acquired immunity of people living in such rural endemic areas, we should count also the possibility of subclinical infections naturally occurring among people.
Please, if interested in filoviruses world, take a look to FILOVIR website.
Thanks, Luca.