Ebola virus, a silent murderer
An epidemic of the disease Ebola virus unprecedented size continues in some parts of West Africa. For the first time, large urban centers such as Conakry, capital of Guinea, are affected. We did an observational study of patients with Ebola virus disease in three regions of Guinea Conakry, including with the aim of tracing the routes of transmission and evaluate the impact of interventions.
Methods to study the transmission of Ebola virus
Between February 10, 2014, and August 25, 2014, data LineList of all confirmed and probable Guinea (as of September 16, 2014) cases, a database of laboratory information on patients were obtained, and interviews with patients and their families and neighbors. With this information, we studied the transmission chains, identified adjustment infections most likely originated from (community, hospital or funeral), and calculate the specific numbers of context and reproduction in general.
Of the 193 confirmed and probable cases of the disease Ebola virus reported in Conakry, Boffa and Telimele, 152 (79%) were placed in chains of transmission. Health workers have contributed little to the transmission. In March 2014, people with the disease Ebola virus who were not infected health workers an average of 2 • 3 people (95% CI: 1 • 6-3 • 2): 1 • 4 (0 • 09/02 • 2) in the community, 0 • 4 (0 • 1-0 • 9) in hospitals, and 0 • 5 (0 • 2/1 • 0) at funerals. After application of infection control in April, the number of reproduction in hospitals and at funerals reduced to less than 0 • 1. In the community, the reproduction number was reduced by 50% for patients who were admitted to the hospital, but remained unchanged for those who were not. In March, hospital transmissions accounted for 35% (seven of 20) of all transmissions and transmissions funeral accounted for 15% (three); but from April until the end of the study period, they were only 9% (11 of 128) and 4% (five), respectively. 82% (119 of 145) of transmission occurred in the community and 72% (105) among family members. Our simulations show that a 10% increase in hospital admissions could have reduced the length of the chain by 26% (95% CI: 4-45).
In Conakry, interventions have the potential to stop the epidemic, but reintroductions of disease and poor cooperation of a few families led to prolonged low level expansion, showing the challenges of fighting disease Ebola virus in large urban centers. Monitoring of transmission chains is crucial to evaluate and optimize local control strategies disease Ebola virus.
Introduction of the Ebola virus epidemic
An epidemic of the disease Ebola virus unprecedented size has been ongoing for about a year in parts of West Africa. As of January 11, 2015, among suspected cases, confirmed cases and suspected cases have been counted 21,296 people affected by the Ebola virus and a total of 8,429 deaths.
1 With a fatality rate of 70% about 0.2 Guinea, Liberia and Sierra Leone have been the most affected, although Nigeria and Senegal have also reported cases. WHO3 declared the epidemic a public health emergency of international importance on Aug 8, 2014. The US Spain reported hospital and transmissions.
The transmission of Ebola virus disease occurs by direct contact with body fluids of symptomatic patients infected with Ebola virus. Care of patients in hospitals or family or community and funeral agencies are two important routes of infection. Since patients become infectious after 11 days (range 2-21 days) .The average incubation is 2 days.
The contacts that have been exposed to Ebola virus can be identified, monitored, and when symptoms appear, should be isolated to limit the spread. Therefore, strategies multifaceted check against disease Ebola virus including strict infection control in hospitals and funerals together with active case finding and isolation and identification and tracking contacts, It is believed to be sufficient to stop the epidemic. However, after the first failed containment, there has been general agreement so the dramatic improvement in control measures would be needed to stop this epidemic. As more resources become available strategic decisions, to control the epidemic, these should be based on the experience gained in the field.
Researchers have described the clinical, case fatality rates, and key periods of time, but a detailed quantification of transmission routes and the effect of specific interventions is also needed. Overall growth in the number of cases (for example, doubling times and overall figures of reproduction) have been characteristic, but many questions remain unanswered. What are the relative contributions of hospitals and funerals to spread? What has been the effect of infection control in these places? What is the effect of hospitalization in transmission in the community? Are the high population densities in urban centers to increase transmission opportunities? How mobility in and out of these areas are involved in the transmission and control?
Here the chains of disease transmission of Ebola virus are described and used Conakry, capital of Guinea being the first urban center where more and more affected by the Ebola virus disease, as a case study. From February to August 2014, Conakry was affected by three consecutive outbreaks of Ebola virus disease, which resulted in two new outbreaks in Boffa and Telimele. the role of the different modes of transmission and the effect of control measures in these three prefectures during this period was evaluated.
Follow all the news here.