Ebola crisis – Frequently asked questions about the Ebola crisis from the World Health Organisation.

Ebola crisis
Ebola crisis
Yesterday the World Health Organisation shared some responses to a number of frequently asked questions they have received from journalists and members of the public about the ongoing Ebola crisis.

At PatientTalk we thought it would be useful to share these with our readers.

Are the Ebola outbreaks in Nigeria and Senegal over?

Not quite yet.

If the active surveillance for new cases that is currently in place continues, and no new cases are detected, WHO will declare the end of the outbreak of Ebola virus disease in Senegal on Friday 17 October. Likewise, Nigeria is expected to have passed through the requisite 42 days, with active surveillance for new cases in place and none detected, on Monday 20 October.

For Nigeria, WHO confirms that tracing of people known to have contact with an Ebola patient reached 100% in Lagos and 98% in Port Harcourt. In a piece of world-class epidemiological detective work, all confirmed cases in Nigeria were eventually linked back to the Liberian air traveller who introduced the virus into the country on 20 July.

The anticipated declaration by WHO that the outbreaks in these 2 countries are over will give the world some welcome news in an epidemic that elsewhere remains out of control in 3 West African nations.

In Guinea, Liberia, and Sierra Leone, new cases continue to explode in areas that looked like they were coming under control. An unusual characteristic of this epidemic is a persistent cyclical pattern of gradual dips in the number of new cases, followed by sudden flare-ups. WHO epidemiologists see no signs that the outbreaks in any of these 3 countries are coming under control.

How does WHO declare the end of an Ebola outbreak?

A WHO subcommittee on surveillance, epidemiology, and laboratory testing is responsible for establishing the date of the end of an Ebola outbreak.

The date is fixed according to rigorous epidemiological criteria that include the date when the last case with a high-risk exposure completes 21 days of close medical monitoring and tests negative for the virus.

According to WHO recommendations, health care workers who have attended patients or cleaned their rooms should be considered as “close contacts” and monitored for 21 days after the last exposure, even if their contact with a patient occurred when they were fully protected by wearing personal protective equipment.

For health care workers, the date of the “last infectious contact” is the day when the last patient in a health facility tests negative using a real-time reverse-transcriptase polymerase chain reaction (RT-PCR) test.

For WHO to declare an Ebola outbreak over, a country must pass through 42 days, with active surveillance demonstrably in place, supported by good diagnostic capacity, and with no new cases detected. Active surveillance is essential to detect chains of transmission that might otherwise remain hidden.

Incubation period

The period of 42 days, with active case-finding in place, is twice the maximum incubation period for Ebola virus disease and is considered by WHO as sufficient to generate confidence in a declaration that an Ebola outbreak has ended.

Recent studies conducted in West Africa have demonstrated that 95% of confirmed cases have an incubation period in the range of 1 to 21 days; 98% have an incubation period that falls within the 1 to 42 day interval. WHO is therefore confident that detection of no new cases, with active surveillance in place, throughout this 42-day period means that an Ebola outbreak is indeed over.

The announcement that the outbreaks are over, in line with the dates fixed by the subcommittee on surveillance, epidemiology, and laboratory testing, is made by the governments of the affected countries in close collaboration with WHO and its international partners.

WHO recommendations for testing for Ebola virus disease and confirming a case

WHO is alarmed by media reports of suspected Ebola cases imported into new countries that are said, by government officials or ministries of health, to be discarded as “negative” within hours after the suspected case enters the country.

Such rapid determination of infection status is impossible, casting grave doubts on some of the official information that is being communicated to the public and the media.
• For early detection of Ebola virus in suspected or probable cases, detection of viral ribonucleic acid (RNA) or viral antigen are the recommended tests.
• Laboratory-confirmed cases must test positive for the presence of the Ebola virus, either by detection of viral RNA by RT-PCR, and/or by detection of Ebola antigen by a specific Antigen detection test, and/or by detection of immunoglobulin M (IgM) antibodies directed against Ebola.
• Two negative RT-PCR test results, at least 48 hours apart, are required for a clinically asymptomatic patient to be discharged from hospital, or for a suspected Ebola case to be discarded as testing negative for the virus.
• Laboratory results should be communicated to WHO as quickly as possible, in addition to reporting under the requirements and within the timelines set out in the International Health Regulations, which are administered by WHO.

WHO recommends that the first 25 positive cases and 50 negative specimens detected by a country without a recognized national reference viral haemorrhagic fever laboratory should be sent for secondary confirmatory testing to a WHO collaborating centre, designed as specialized in the safe detection (at biosafety level IV) of viral haemorrhagic fevers.

Similarly, for countries with a national reference laboratory for viral haemorrhagic fevers, the initial positive cases should also be sent to a WHO collaborating centre for confirmation.

If results are concordant, laboratory results reported from the national reference laboratory would be accepted by WHO.
• For more information read WHO recommendations on laboratory guidance for the diagnosis of Ebola virus disease

“Risk of Ebola spreading in Europe is very low” say World Health Authority

Ebola Crisis
Ebola Crisis
We have covered the Ebola virus before but with recent developments in the USA and the European Union we think it would be useful to extend our coverage during the crisis.

We would also be very interested in finding out what your ideas are to stop the spread of the virus. That being said the World Health Organisation shared the following with us yesterday. “Sporadic cases of Ebola virus disease in Europe are unavoidable. This is due to travel between Europe and affected countries.

However, the risk of spread of Ebola in Europe is avoidable and extremely low. European countries are among the best prepared in the world to respond to viral haemorrhagic fever (VHF) including Ebola.

There is a risk of accidental contamination for people exposed to Ebola patients: this risk can be and must be mitigated with strict infection control measures. Health care workers are on the frontline of the Ebola fight and they are those most at risk of infection. They need to be protected and supported by all means.

All countries have protocols and procedures that must be implemented when a case is suspected and it is important that these are followed diligently. WHO is, as always, ready to provide help and support where requested.”

The latest edition of the Ebola Response Roadmap Situation Report was published yesterday. You can read it here.

Study warns swift action needed to curb exponential climb in Ebola outbreak – says New England Journal of Medicine

Ebola Outbreak News
Ebola Outbreak News
Like many of my readers I have been following the recent Ebola outbreak with some concern. I was send the following information this morning which I thought would be useful to share.

Unless Ebola control measures in West Africa are enhanced quickly, experts from the World Health Organization (WHO) and Imperial College, London, predict numbers will continue to climb exponentially, and more than 20,000 people will have been infected by early November, according to a new article in the New England Journal of Medicine released six months after WHO was first notified of the outbreak in West Africa.

In the article, public health epidemiologists and statisticians reviewed data since the beginning of the outbreak in December 2013 to determine the scale of the epidemic, better understand the spread of the disease, and what it will take to reverse the trend of infections.

Scale of epidemic

Although WHO was first notified of the outbreak on 23 March 2014, investigations retroactively revealed the outbreak started in December 2013. Between 30 December 2013 and 14 September 2014, a total of 4507 cases were reported to WHO.

The data in the study help clarify some details of who is most affected by this outbreak. For example, there have been mixed reports on whether women might be harder hit because they are more likely to care for sick, or whether it would be men who might be more likely to bury the highly-infectious dead bodies.

“This study gave us some real insight into how this outbreak was working, for example, we learned there is no significant difference among the different countries in the total numbers of male and female case patients,” says Dr Christopher Dye, Director of Strategy for WHO, and co-author of the study. “There may be differences in some communities, but when we actually looked at all the data combined, we saw it was really almost split 50-50.”

The extensive review of data also allowed for a closer look at case fatality rate.

“Assessing the case fatality rate during this epidemic is complicated by incomplete information on the clinical outcomes of many cases, both detected and undetected,” says Dye. “This analysis shows that by 14 September, a total of 70.8% of patients with definitive outcomes have died. This rate was consistent among Guinea, Liberia and Sierra Leone.”

But the case fatality rate was lower when only hospitalized patients were considered, supporting evidence that getting patients to good, supportive health care quickly makes a difference.

Spread of infection

The examination of the data also showed the spread more clearly. In late December, the first cases were reported in the forest areas of Guinea. By March, when the government sounded the alarm to WHO, cases had already spread from the forest area to the capital of Conakry. In May, the focus of the outbreak in Guinea expanded strongly to Sierra Leone and in June it really took hold in Liberia. From July onward, there were sharp increases in case numbers in all three countries.


Although the current epidemic in West Africa is unprecedented in scale, the clinical course of infection and the transmissibility of the virus are similar to those in previous Ebola outbreaks.
“We infer that the present epidemic is exceptionally large, not primarily because of biologic characteristics of the virus, but in part because of the attributes of the affected populations, the condition of the health systems, and because control efforts have been insufficient to halt the spread of infection,” says Dye.

There are challenges in this region that exacerbate the struggles to contain the virus quickly. Most importantly the health systems in all three countries were shattered after years of conflict and there was a significant shortage of health workers, leaving the system weaker than in other countries with Ebola outbreaks. In addition, certain characteristics of the population may have led to the rapid spread of the disease, for example, the populations of Guinea, Liberia, and Sierra Leone are highly interconnected, with extensive cross-border traffic at the epicentre and relatively easy connections by road between rural towns and villages and the densely populated capital cities.
“The large intermixing population has facilitated the spread of infection, but a large outbreak was not inevitable,” says Professor Christl Donnelly, Professor of Statistical Epidemiology, Imperial College and the MRC Centre for Outbreak Analysis and Modelling. “In Nigeria, for example, where health systems are stronger, the number of cases has so far been limited, despite the introduction of infection into the large cities of Lagos and Port Harcourt.“

The critical determinant of outbreak size appears to be the speed of implementation of rigorous control measures.

“Forward projections suggest that unless control measures – including improvements in contract tracing, adequate case isolation, increased quality of care and capacity for clinical management, greater community engagement, and support from international partners – improve quickly, these three countries will soon be reporting thousands of cases and deaths each week,” says Dye.
Experimental therapeutics and vaccines offer promise for the future, but are unlikely to be available in the quantities needed to make a substantial difference in control efforts for many months, even if they are proved to be safe and effective.

The risk of continued expansion of the Ebola outbreak is real. This study provides the evidence needed for an urgent wakeup call requiring intensive scaling up of control measures while working towards rapid development and deployment of new medicines and vaccines.