Bats and bat hunters in northeast India carry reactive antibodies to the Ebola and Marburg viruses according to the research, indicating that the filoviruses associated with the disease circulate among the local bat population. This presents the opportunity for animal-to-human (zoonotic) transmission of the disease which, in the worst case scenario, could result in an outbreak of Ebola similar to that witnessed in the Democratic Republic of the Congo (DRC).
Fears of Ebola spreading to India were voiced earlier this year by Dr Balram Bhargava, director general of the Indian Council of Medical Research (ICMR). Bhargava said that “nearly 30,000 Indians live in Uganda, where Ebola has been reported. Some of our troops are also present in the [DRC], where the viral infection has led to an outbreak situation at present.”
The disease is currently running rampant throughout the civil war-ravaged DRC. Due to conflicts, treatment efforts have been impeded and the disease is beginning to spill across the borders into neighbouring nations such as Uganda – hence Bhargava’s fears.
Ebola ranks among the most prominent causes of potential future epidemics due to the fact that it is not only highly contagious, but has a mortality rate of around seventy percent. The disease is spread through bodily fluids. Much like India’s struggle with cholera, open defecation in rural areas could exacerbate the spread of the condition should it reach India.
“At this point, it is unclear if any human was infected with a filovirus at any point, keeping in mind that the exposure to noninfectious parts of the virus can give rise to an immune response,” said Dr Ian Mendenhall, principal research scientist in the Laboratory of Virus Evolution at Duke-National University of Singapore Medical School.
According to the study, no filovirus genetic material was detected in bat blood or tissues. This means that no bats studied currently harboured the Ebola virus. However, Mendenhall and colleagues found filovirus antibodies in 5.9 percent of human samples, 6.2 percent of E. spelaea samples and 13.3 percent of R. leschenaultii samples. The implication of this is that these cases had been exposed to at least partial antigens of the virus.
It was noted by the study that the potential virus present in the bats may not be an exact copy of the virus responsible for the present outbreak in the DRC. It may be less pathogenic, and therefore far less likely to spread to humans. They note that as of yet there is no evidence that the area is prone to an outbreak, though have used the study to highlight the need for zoonotic analysis for potential disease cases.