virology blog
About viruses and viral disease
From the European Congress of Virology in Rotterdam, Vincent and local co-host Ben Berkhout speak with Ron Fouchier, Rosina Girones, and Marie-Paule Kieny about their careers and their work on influenza virus, environmental virology, and developing an Ebola virus vaccine during an epidemic.
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Download TWiV 557 (41 MB .mp3, 67 min)
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Show notes at microbe.tv/twiv
Vincent visits the Smithsonian Institution and speaks with Sabrina Sholts, Jon Epstein, and Ed Niles about the exhibit Outbreak: Epidemics in a Connected World.
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Download TWiV 501 (54 MB .mp3, 90 min)
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Show notes at microbe.tv/twiv
On episode #327 of the science show This Week in Virology, the eTWiVicators review evidence that the HIV-1 group O epidemic began with a single cross-species transmission of virus from western lowland gorillas.
You can find TWiV #327 at www.microbe.tv/twiv.
The World Health Organization held a conference to assess the status of testing and eventual licensing of two candidate Ebola virus vaccines. The agenda and list of participants and the final report are available. I was interested in the following list of key expected milestones:
October 2014:
Mechanisms for evaluating and sharing data in real time must be prepared and agreed upon and the remainder of the phase 1 trials must be started
October–November 2014:
Agreed common protocols (including for phase 2 studies) across different sites must be developed
October–November 2014:
Preparation of sites in affected countries for phase 2 b should start as soon as possible
November–December 2014:
Initial safety data from phase 1 trials will be available
January 2015:
GMP (Good Manufacturing Practices) grade vaccine doses will be available for phase 2 as soon as possible
January–February 2015:
Phase 2 studies to be approved and initiated in affected and non-affected countries (as appropriate)
As soon as possible after data on efficacy become available:
Planning for large-scale vaccination, including systems for vaccine financing, allocation, and use.
I wonder how a phase 2 study will be conducted, the goal of which is to determine if it is effective and further evaluate its safety. Will this be done in west Africa, where protection against Ebola virus infection can be assessed? If so, will there be controls who receive placebo?
If indeed an Ebola virus vaccine is our best hope in limiting the current outbreak, it won’t be distributed for a while, according to the optimistic expectations of WHO – assuming all proceeds on time, and that the results are favorable.
On episode #305 of the science show This Week in Virology, Vincent, Alan, and Kathy continue their coverage of the Ebola virus outbreak in West Africa, with a discussion of case fatality ratio, reproductive index, a conspiracy theory, and spread of the virus to the United States.
You can find TWiV #305 at www.microbe.tv/twiv.
Given the extent of the Ebola virus outbreak in West Africa, transport of an infected individual to the US was bound to happen. The case is an adult who had contact with an Ebola virus-infected woman in Liberia, then traveled to Dallas. He had no symptoms before arriving in the US and therefore did not likely transmit the infection to airplane passengers. He sought medical care on 26 Sep 2014 and was admitted to Texas Health Presbyterian Hospital 28 Sep 2014 where he is currently under isolation. Samples sent to the CDC tested positive for Ebola virus. There are excellent summaries of the events at ProMedMail and the CDC website.
Apparently the Dallas patient told a healthcare worker during his first hospital visit that he had been in Liberia. This information was not transmitted to his physician. The word ‘Liberia’ should have set off alarm bells. Furthermore, if the physician did not receive the patient’s recent travel history, he/she should have requested it. There is no room for error when dealing with Ebola virus infection.
It is puzzling that travel (excluding healthcare workers) out of the affected West African countries is still permitted. As moderator JW notes on ProMedMail: “This chain of events illustrates the danger that anybody arriving from Liberia, even without symptoms on departure from there or on arrival in the USA (or anywhere else in Africa or overseas) may be incubating Ebola — but not international volunteers who have only been in contact with Liberians while wearing adequate PPE (personal protection equipment).”
Why is it important to stop travel out of the affected countries? While I’m confident that the US can detect and properly contain imported Ebola virus infections, not all countries will be able to do so. There are dozens of other countries that are unprepared to deal with an infected case, from diagnosis to isolation to treatment. I can easily imagine infection quickly getting out of control in such countries: millions are at risk. While the economics of stopping air travel out of Liberia, Sierra Leone, and Guinea will be severe, they cannot approach the devastation of having outbreaks burning simultaneously in multiple countries.
Update: NPR has a good explanation of the reproductive index, or the number of persons who can be infected by another infected person during an outbreak. For Ebola virus, this number is 1-2. This low number is why quarantine can be effective.