A transmission electron micrograph shows Ebola virus particles in this undated handout image released by the U.S. Army Medical Research Institute of Infectious Diseases (USAMRIID) in Fredrick, Maryland.Reuters

The genetic structure of the current Ebola strain has undergone rapid changes over the years and could interfere with the treatments currently available to fight the deadly disease, latest research shows.

Researchers from the U.S. Army Medical Research Institute of Infectious Diseases (USAMRIID) in Frederick, Maryland, have identified about 600 genetic mutations called single nucleotide polymorphisms (SNPs) in EBOV/Mak, the strain involved in the current Ebola outbreak.

"The virus mutates rapidly and it's an ongoing concern," lead author of the study Jeffrey Kugelman, a viral geneticist at USAMRIID, said in a statement appeared in Medicalxpress.

Ebola drugs work by aiming either at a section of the virus's genetic sequence or a protein sequence acquired from the genetic sequence. A genetic change, so, can affect the proper functioning of the medication and fail to give the desired results.

The drugs developed in the early 2000's may be less effective as they were based on virus strains involved in the 1976 and 1995 Ebola outbreaks, the authors said.

During their research, the team conducted a comparative study of EBOV/Mak with the EBOV/Yam-May strain responsible for the 1976 outbreak in Yambuku and EBOV/Kik-9510621, which was involved in the 1995 outbreak in Kikwit. Both places are located in Democratic Republic of the Congo.

Of the total 60 mutations identified during the study, 10 posed a risk to the proper working of certain drugs developed to fight off the disease currently-monoclonal antibody, siRNAs (small-interfering RNA) and PMOs (phosphorodiamidate morpholino oligomer).

"The virus has not only changed since these therapies were designed, but it's continuing to change," Kugelman said. "Ebola researchers need to assess drug efficacy in a timely manner to make sure that valuable resources are not spent developing therapies that no longer work."

The study reported in mBio comes at a time when the deadly virus continues its successful stride across three South African countries -Liberia (8,331 cases and 3,538 deaths), Sierra Leone (10,124 cases and 3,062 deaths) and Guinea (2,806 cases and 1,814 deaths).

Ebola has, so far, killed 8,429 people and infected 21,296 people around the world.