How Ebola spread and became deadliest disease
The Ebola virus outbreak in West Africa has emerged as a new medical challenge and poses a serious threat to the rest of the African region and the world at large. Researchers are still trying to ascertain the causes, key factors involved, and are also trying to forecast the future eruption and movement of the virus.
The outbreak of the Ebola triggered with Ebola cases that turned up in Guinea, and subsequently spread to the neighbouring countries of Liberia and Sierra Leone. This is particularly surprising as until now, none of these three West African countries had ever experienced an Ebola outbreak, let alone cases of a type of Ebola virus that had been detected only in distant Central Africa.
But, as per scientists, despite the image of Ebola as a virus that furtively and randomly emerges from the forest, the sites of the cases are far from random. Scientists are of the view that the outbreak has a connection with the travel patterns of bats across Africa and current weather patterns in the region, as well as other factors.
Researchers have narrowed down to five potential reasons why this outbreak is so severe:
- Involvement of deadliest type of Ebola virus: The Ebola virus has 5 species, and each species has caused outbreaks in different regions. Surprisingly, instead of the Taï Forest Ebola virus, which is found near Guinea, it was the Zaire Ebola virus that is involved in the current outbreak. This virus was previously found only in three countries in Central Africa: the Democratic Republic of the Congo, the Republic of the Congo and Gabon. Zaire Ebola virus is the deadliest type of Ebola virus — in previous outbreaks it showed a fatality rate of up to 90% which means it kills 90 out of 100 people it infects. Scientists suspect bats to be the carrier of the virus that migrated from Zaire to Guinea. It is also possible that the virus was actually in West Africa before the current eruption, circulating in bats — and possibly even infected people but so infrequently that it was never reported. Some preliminary investigation of blood samples gathered from patients with other diseases before the outbreak indicates people in this region were exposed to Ebola previously but the finding still needs more research.
- Poorest countries getting affected: Guinea is one of the poorest countries in the world, which has been ranked as low as 178 out of 187 nations on the United Nations’ Human Development Index (HDI). Likewise, Liberia and Sierra Leone stand at 174th and 177th on the HDI respectively. Because of prevalent poverty, they are inadequately equipped to counter an outbreak and lack coordination to monitor people’s movements across regions.
- Lack of good health care systems: A poor economy translates into weak health care systems that are not ready to respond to an outbreak and lack even basic health resources. The hospitals in the region do not have even basic medical needs like protective gloves, masks, clean needles and disinfectants.
- Poverty forcing people to move towards forests: Normally the animals carrying or infected with the Ebola virus or other pathogens are not usually in the vicinity of humans, but rather deep in the forests with little possibility of coming into contact with people. However, poverty is pushing the people deeper into forest territories to search for resources.
- Extremely dry season may have been the trigger: The first case of Ebola was reported in Guinea in December 2013, at the start of the dry season. In other countries, too, outbreaks often occur during the transition from the rainy to dry seasons, when conditions become drier sharply. It is likely that drier conditions one way or another affect the number or proportion of bats infected with the Ebola virus, or the frequency of human contact with them.