Fight against little-known Zika virus applies lessons from Ebola
While the world's attention has been focussed on Ebola, another outbreak has been spreading in a number of countries across the world. Now, Oxford University infectious disease specialists are applying the lessons from the Ebola outbreak to try to support local medics and researchers to get ahead of this new pathogen.
14 jan 2016--Zika, carried by the Aedes mosquito, has been known about for some years, typically causing mild illness and a rash. Now, however, reports from South America suggest that it is causing birth defects in newborn babies of women who have had Zika.
The outbreak came to the attention of two Oxford-based organisations: The Global Health Network (TGHN), an online science park that guides and supports medical research around the world, especially in low and middle income countries and ISARIC, a global network of researcher groups whose aim is to enable research in disease outbreaks
Professor Trudie Lang explained: 'I was at an ISARIC meeting about Ebola when Fernando Bozza of the Oswaldo Cruz Foundation told us about the Zika outbreak He asked what we knew about the Zika outbreak. The answer was not much.
'He briefed the ISARIC team and it was clear this was another situation where the research community had to come together to ensure that evidence was gathered as early as possible this time, and that we should apply the lessons from Ebola that we were discussing at that very meeting.'
Zika has been known about since the late 1940s but major outbreaks were not recorded until a 2006 occurrence on the pacific island of Yap. In 2013 there were 30,000 cases in French Polynesia.
However, the South American outbreak is particularly concerning because if its apparent effect on foetal development. Dr Fernando Bozza said: 'Zika Virus has been reported in Brazil since April 2015 and up to mid-December, nine other countries in the Americas have reported local Zika transmission.
'In November, the Brazilian Ministry of Health reported an unusual increase in cases of microcephaly, with a causal link between Zika infection during pregnancy and congenital abnormalities. 2,401 microcephaly cases are under investigation in Brazil, with 134 cases confirmed related to Zika virus infection. Investigations are also ongoing to assess a possible relation between Zika and Guillain-Barré Syndrome and other neurological events.'
With Zika becoming a more serious disease, The Global Health Network recognised the need to move as rapidly as possible into obtaining data, which requires the integration of research into the medical and public health response. Developing research tools and strategies is key and this needed a resource for agreeing research priorities and sharing research documents
Professor Lang said: 'Medical research is vital to understand, manage and hopefully stop the outbreak. However, if samples and patient information are to be used for research purposes then protocols are needed that have been given ethical approval by regulatory authorities and patients need to be informed and asked for their consent. Robust studies need to be planned and this all takes time to put into place. However, a lesson from Ebola was that it can be done faster. The researchers in the affected regions are poised to run and lead these studies, and the international research community, through ISARIC, is working to support them and provide any input and external expertise that is needed.
'The Global Health Network's website for Zika has been set up for the local research community. It will make available documents like case record forms and consent forms, as well as sharing research priorities. By providing a common and open sharing space that is driven by the regional researchers in Brazil and other countries it should be possible to speed up getting this crucial data that is needed to understand, manage and eventually treat Zika virus infection.'
The hope is that a joined up approach, where frontline health organisations are supported by a global network, will mean Zika is understood quicker and that work on treatments can begin sooner.
22 oct 2014--The highly contagious Ebola virus, which has killed more than 4,500 people in west Africa since December and has fueled global alarm, is among the most dangerous ever identified.
Where did it come from?
Like AIDS, which began in Kinshasa in the 1920s before spreading worldwide, according to a recent study, Ebola was first identified in central Africa.
The tropical virus was named after a river in the Democratic Republic of Congo, where it came to light in 1976.
Five species have been identified to date (Zaire, Sudan, Bundibugyo, Reston and Tai Forest), the first being the most dangerous with death rates that have reached 90 percent among humans.
The death rate in the current epidemic of haemorrhagic fever is around 70 percent according to the World Health Organization (WHO).
How is it transmitted?
The virus' natural reservoir animal is probably the bat, which does not contract the disease itself.
Chimpanzees, gorillas, monkeys, forest antelope and porcupines have also been found to transmit Ebola to humans.
Only one certified contact with an animal has been recorded in the current outbreak, however, early on in Guinea, following which it has been passed on among humans.
Although it is highly contagious, Ebola is transmitted less easily than some other diseases. An average of two people have been infected by each person who has contracted the disease since December.
This is because Ebola is transmitted by contact with the blood, body fluids, secretions or organs of an infected person, but not by air.
Those infected do not become contagious until the symptoms appear. They then become more and more contagious until just after their death, which poses great risks during funerals.
Following an incubation period of between two and 21 days, five being the average according to a Swiss study, Ebola develops into a high fever, weakness, intense muscle and joint pain, headaches and sore throats.
That is often followed by vomiting and diarrhoea, skin eruptions, kidney and liver failure, and internal and external bleeding.
How can it be treated?
Because there is no approved drug treatment at present, patients are essentially re-hydrated.
A series of experimental treatments have nonetheless resulted in positive results among several patients.
The best known is ZMapp, a cocktail of three monoclonal (single cell) antibiotics developed through a Canadian/US partnership, of which several hundred doses are expected to become available by the end of this year.
Avignan, an anti-flu treatment developed by the Japanese firm Toyama Chemical, could be available rapidly but it has not yet been proven sufficiently effective against the Ebola virus.
Toyama Chemical says it has enough Avignan in stock for more than 20,000 people.
Two vaccines have been deemed promising by the WHO and their development has been speeded up. They are the Canadian drug VSV-EBOV, of which 1,000 doses were sent to the WHO this week, and cAd3-ZEBOV, made by the British pharmaceutical group GlaxoSmithKline, which is not expected to be ready before 2016.
How can you protect yourself?
Ebola is best treated preventively, notably through hand-washing and using gel- or alcohol-based disinfectants. The required procedure is simple but must be done rigorously, and anyone suspected of exposure must check carefully for symptoms, especially fever.
It is recommended to keep a distance of several metres (yards) from infected people or bodies, and health-care providers must wear disposable protection clothing that includes masks and gloves.
Sites that have been contaminated must be disinfected.
How to defeat Ebola?
Patients must first be identified through laboratory tests because the symptoms resemble those of other diseases such as malaria. Those infected must be isolated.
Ebola treatment centres require substantial means: WHO estimates that it takes between 200-250 medical personnel to safely staff a centre of 70 beds.
All people in contact with an infected person must be closely watched for 21 days to ensure they have not contracted the disease.
The United Nations has estimated it will take around $1.0 billion (780 million euros) to fight Ebola over the next six months, but less than 40 percent of that amount has been received so far.
The money is needed to increase the number of available beds to 7,000 from 4,300 at present by December 1 and to provide the required number of personnel.
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Thursday, October 16, 2014
How are nurses becoming infected with Ebola?
Credit: CDC
16 oct 2014--American nurse Nina Pham is the second health worker to contract Ebola outside of West Africa while caring for patients with the virus, despite using personal protective equipment. Authorities were quick to attribute lapses in protocol for Pham's and Madrid nurse Teresa Romero Ramos' infection. But inadequate guidelines for personal protective equipment (PPE) may equally be to blame.
The World Health Organization (WHO), United States Centers for Disease Control (CDC), Australia and many countries recommend health workers treating Ebola wear surgical masks for protection, along with other personal protective equipment such gowns, gloves and goggles.
A glaring inconsistency of these guidelines is that lab scientists working with Ebola are recommended to use respirators, which offer more protection than surgical masks, while masks are deemed adequate for doctors and nurses at the front line. The hospital ward, however, is a far more contaminated and volatile environment than the sterile, highly controlled lab.
Nurses have the closest contact with patients, and deserve all available protection for their occupational health and safety. This means higher personal protective equipment, including respirators.
The CDC's most recent guideline update for putting on and removing protective wear suggest the second glove can be removed by hooking a bare finger under the glove (risking contact with the outside of the glove which could be contaminated), and does not mention protective boots at all.
Non-government organisations such as Medecins Sans Frontieres (MSF), however, have more comprehensive Ebola-specific protocols on glove removal, footwear and the use of respirators.
Ebola kills 50% to 90% of people who become infected, which is much higher than any other infection we are used to dealing with. The 2009 influenza pandemic killed less than 0.01% of those infected, and SARS killed 15%.
The price of getting it wrong with flu guidelines might be a week in bed, but for Ebola it is far more likely to be death. The risk analysis equation we need to use must consider not only the probability of Ebola turning up on our shores, but also the consequences.
Unprecedented epidemic
The current West African Ebola outbreak has caused more than 8000 cases and more than 4000 deaths, with the epicentre being Guinea, Sierra Leone and Liberia. Official figures are underestimated because many cases are not reaching health-care facilities or being reported.
As the epidemic increases exponentially in West Africa there is a risk of imported cases occurring around the world. The first of these was in Dallas, Texas, but countries everywhere are on the alert for suspected cases. Experts have estimated that the risk of a travel-related case being imported into Europe is up to 75% by the end of October.
This epidemic is unprecedented because:
It is the largest and longest in history;
It is the first time Ebola has occurred in more than one country simultaneously;
It is the first time Ebola has affected urban areas and capital cities; and
It is the first time Ebola has been transmitted from person to person outside of Africa.
Health authorities such as the US CDC are conveying certainty that Ebola cannot be transmitted by any means other than direct contact. But it's a very poorly studied infection compared with other diseases and the sum of the evidence shows significant uncertainty around transmission.
The prevailing view is that infections can only be transmitted by one of three mutually exclusive routes – contact, droplet or airborne. But this is based on experiments from the 1940s and 50s using blunt instruments. There is plenty of evidence that pathogen transmission is far more complex than this, and that most pathogens can be transmitted by several modes. Take influenza, for example.
While the predominant mode of transmission of Ebola is contact, some scientists believe it could also be spread by aerosols. Studies in monkeys and pigs have demonstrated non-contact transmission of Ebola, which could be airborne or aerosol.
There is little research in humans, but in a 1995 outbreak in the Democratic Republic of Congo, five people contracted Ebola without reporting any direct contact with the index patient.
Health worker infections
The estimated infectious potential of Ebola in West Africa is similar to influenza. Each person with Ebola infects, on average, two other people, which is similar to estimates for the last pandemic of flu. It is a mystery why an infection that is supposedly only transmitted by contact has such a high infection rate.
Around 400 health-care workers have contracted Ebola during this outbreak, many of whom are unsure how they were infected. Dr Kent Brantley, for instance, is certain he did not get infected in the Ebola ward, as he used strict personal protective equipment. He guesses he might have been infected elsewhere, such as the emergency room.
Dr Sheikh Hummar Khan was the leading viral haemorrhagic fever expert of Sierra Leone, who had already treated over 100 Ebola patients using full personal protective equipment when he died from Ebola.
Why then are so many health workers contracting Ebola when it is supposedly so "hard to catch"? There are three possible explanations:
Lapses in infection control protocols, such as mistakes when putting protective equipment on or taking it off.
Inadequate guidelines that are failing to protect against other (non-contact) modes of transmission.
Health workers are becoming infected somewhere other than where they're in direct patient contact (where they do not expect to be at risk). This is possible in West Africa with such a large scale epidemic, but is unlikely in the United States and Spain.
There is no scientific evidence to explain why health workers using personal protective equipment are becoming infected, and nor has there been a reasoned approach to trying to explain it.
Instead, the blame has been placed on the health workers for lapsing in personal protective equipment protocols. It was reported Ramos might have touched her face with a glove as she removed her personal protective equipment.
In epidemiology, we are concerned about recall bias: the tendency of people with an illness to recall perceived risks more than well people, when prompted with a leading question. It is not hard to imagine that this nurse, perplexed about how she might have been infected, would have been susceptible to such a leading question.
Rather than guesses, we need a reasoned, scientific approach to establishing which of these explanations – and it may be a combination – are responsible.
Personal protective equipment guidelines should not be based on presumed mode of transmission alone, but also on uncertainty around transmission, on the severity of the disease, on health worker factors, and on other available treatments or preventions. If MSF has more comprehensive protocols on protective wear, it is hard to understand why Western countries are not heeding them.
Protecting health workers
Many dedicated health workers around the world are assisting with the response to Ebola. Some responders are non-clinicians, and that some clinician responders do not have extensive infectious diseases training. There is a clear occupational health and safety risk to health workers from this deadly disease, which is concerning.
To better protect health workers from Ebola, the ARM network, a group of Australian epidemiologists with skills in infectious diseases, is offering a free workshop on Ebola infection control to supplement routine training provided by deploying non-government agencies.
The workshop is for people intending to deploy to West Africa for the Ebola response. But due to expressions of interest, we have opened the workshop to domestic first-line responders (GPs, nurses, paramedics, police, defence, emergency workers) in Australia who may be faced with a local case.
In most responses, lack of knowledge about infection control may not be critical, but in the case of Ebola it may cost lives. If even one person learns something at this workshop which enhances their occupational health and safety, then we would have provided something useful for Australians involved in the response.
Provided by The Conversation
Saturday, October 11, 2014
Ebola toll passes 4,000 as fears grow worldwide
The death toll from Ebola has passed 4,000, the World Health Organization warned, as authorities worldwide tried to prevent panic over the deadly disease and a Spanish nurse fought for her life in hospital.
11 oct 2014--The WHO said 4,033 people have died from Ebola as of October 8 out of a total of 8,399 registered cases in seven countries. The sharp rise in deaths came as the UN said aid pledges to fight the outbreak have fallen well short of the $1 billion (800 million euros) needed.
Spanish government officials were due to meet on Saturday morning for a gathering of their new crisis committee to tackle the crisis after a Madrid nurse became the first person to get infected with the haemorrhagic fever outside of Africa.
They have called for calm and vowed to boost health safety protocol and investigate what failings led to the nurse, Teresa Romero, getting infected.
Almost all the deaths have occurred in west Africa, but after Romero's death fears spread beyond that region about the world's worst-ever Ebola epidemic.
The Canadian government advised its citizens on Friday to leave the west African countries hardest hit by Ebola, while taking measures at its own borders to screen for potentially exposed travelers.
The US and Britain also boosted screening at major airports.
The US Centers for Disease Control and Prevention predicted the number of cases could reach 1.4 million by January unless strong measures are taken to contain the disease.
From Australia to Zimbabwe, and Brazil to Spain, people who showed signs of fever or had recent contact with Ebola victims were whisked into isolation units or ordered to stay in their homes.
Authorities warned that hoaxes could trigger panic as a man was taken off a US flight by a bio-hazard team after he sneezed and reportedly said: "I have Ebola. You are all screwed."
Serious concerns remained in Spain over how the virus could have spread in a top specialist disease hospital.
Healthcare workers told AFP the quarantine floor of Carlos III hospital in Madrid, where 44-year-old Romero was infected, was shut last year as a result of spending cuts and only re-opened for the two missionaries flown back from Africa with the disease in August.
Prime Minister Mariano Rajoy visited the hospital, where Romero, who caught Ebola while caring for the missionaries, was said to be in a "stable but serious" condition.
Doctors there took in three more patients for observation Friday bringing to 17 the number under surveillance, including Romero, her husband and other medical staff.
More money needed
The United Nations and leaders of the Ebola-stricken nations of Guinea, Liberia and Sierra Leone pleaded for greater help for the frontline of the disease in Africa.
The president of Guinea, one of the West African nations hard-hit by the Ebola crisis, met Friday with IMF Director Christine Lagarde, who promised the organization was "ready to do more if needed" to fight the disease.
UN Deputy Secretary General Jan Eliasson said only a quarter of "the one billion dollars sought" to combat the disease had been pledged. He appealed for doctors, nurses and other healthcare personnel to come forward.
His comments echoed a plea on Thursday from UN Secretary-General Ban Ki-moon, who said resources to support the fight must be increased 20-fold.
"Cases are growing exponentially," Ban said. "Do not wait for consultation. Just take action."
"We have to work now so that it is not the world's next AIDS," CDC Director Tom Frieden warned the heads of the United Nations, World Bank and International Monetary Fund gathered in Washington Thursday.
In Liberia, where the official death toll was put at 2,316 by the WHO on Friday, the government said it had banned journalists from Ebola clinics, arguing it was to protect patients' privacy.
The move came as nurses at the largest government Ebola clinic in the capital Monrovia staged a "go slow" to demand hazard pay, defying a request by UN health officials to avoid industrial action during the crisis.
In France, a public building was briefly evacuated in a Paris suburb on Thursday when an African man felt ill. Earlier, the arrival of a group of schoolchildren from Guinea had sparked panic at a French school. Ebola was ruled out in both cases.
Macedonia quarantined people who had come into contact with a Briton who died on Thursday after exhibiting Ebola-like symptoms.
Brazilian health officials Friday quarantined a Guinean man feared to have Ebola, but stressed it was a precautionary measure and the man no longer had a fever or other symptoms.
The Moroccan government called for the 2015 Africa Cup of Nations to be postponed due to the epidemic.
Brazil quarantines Guinean feared to have Ebola (Update)
11 oct 2014--Brazilian health officials Friday quarantined a Guinean man feared to have Ebola, but stressed it was a precautionary measure and the man no longer had a fever or other symptoms.
The 47-year-old man had arrived from Africa last month. He checked into a clinic in the town of Cascavel having had a fever on Wednesday, and on Friday was taken in an air force plane from the southern state of Parana to the National Infectious Disease Institute (Fiocruz) in Rio de Janeiro.
"The patient is stable, he does not have a fever nor other symptoms," Health Minister Arthur Chioro told a press conference in Brasilia.
The minister added the patient had told Fiocruz monitors that he had confirmed before leaving Guinea, in a pre-travel screening, that "he had not been in any contact with (Ebola) cases."
However, his case was considered suspect, as the fever presented "within the incubation period" for Ebola of 21 days, Chioro told an initial news conference.
He stressed health authorities had the situation "under control" with all procedures undertaken within the proper response time.
Health officials logged 64 possible contacts between the patient and others after he went to the health center, but only three "direct" contacts with other people, the minister said.
Other patients who were in the clinic with him have also been isolated and the site disinfected, radio network CBN reported.
The patient, who arrived in Brazil on September 19, flew from the Guinean capital Conakry to Argentina, with a layover in Morocco.
He then traveled overland to Brazil, according to television network Globo News, which said he was seeking refugee status.
Parana state had two previous Ebola alerts which proved false alarms.
But the latest case is the first time the alert has reached the level of the national health ministry.
Symptoms of Ebola can resemble other diseases indigenous to Brazil, such as malaria and dengue fever.
Guinea, Liberia and Sierra Leone have been the countries hardest hit by the Ebola outbreak that erupted at the beginning of the year, killing nearly 4,000 people so far—roughly half of those infected.
The disease causes fever, diarrhea, vomiting and in some cases internal and external bleeding.
It is spread by contact and the exchange of bodily fluids.
Tuesday, October 07, 2014
Five things you should know about Ebola virus
Color-enhanced close-up of Ebola virus particles. Credit: Thomas W. Geisbert
07 oct 2014--Last week, the first case of the Ebola virus was confirmed in the United States, a fact that has no doubt caused concern as the number of fatalities in West Africa continues to rise. In an effort to get a little more educated about the disease and its threat now that it's reached the U.S., DrexelNow looked to Esther Chernak, MD, an infectious disease physician and associate professor in the School of Public Health, to provide some insight.
The current outbreak of Ebola virus disease in West Africa is unprecedented in scope. There have been over 20 outbreaks in Africa since the virus was first described in 1976, all of which were relatively limited in size. This outbreak is the only one that has spread to multiple countries. Prior outbreaks had been limited and generally affected no more than 500 people.
Ebola virus is transmitted through contact with the blood or body fluids of an infected person who is symptomatic. People who have been exposed but who are not symptomatic are not contagious. It is not spread through the air, through food or through water. Air travel is an important potential mechanism for the global spread of this disease because people can travel after an exposure to the virus during the long (up to 21 days) incubation period. But because people with the disease are not infectious until they are symptomatic, public information and efforts to screen for fever and symptoms prior to getting on an airplane will keep air travel itself safe for others who are flying.
There is no specific treatment for Ebola virus, and no vaccine to prevent disease. Spread in communities is stopped by isolating infected people and ensuring that others who have physical contact with them are protected with barriers like gloves and gowns. All of the close contacts of Ebola cases must be identified and their health must be monitored closely for 21 days to ensure that signs of the disease are recognized early so they do not pose a threat to others. The best line of defense is a strong health care system, a strong public health system, and an informed public that understands how it is spread and who is at risk.
Ebola virus is not likely to spread in Texas, or anywhere else in the United States, including Philadelphia, even if additional travel-related cases occur, which is quite possible. Once it is recognized, the infection control measures necessary to contain it are well understood and readily available in health care facilities in this country. And the public health system here has great capacity to identify contacts of cases and monitor them to prevent transmission.
The magnitude and severity of the current West African outbreak is the result of a devastating perfect storm: countries with weak health care systems, profound poverty, traditional cultural practices such as the bathing of corpses before burials and touching them during funerals, and a legacy of government distrust after years of civil war, colonialism and corruption. This outbreak is now a humanitarian catastrophe – a slow motion tsunami – with problems above and beyond casualties from Ebola, as health care services and economies unravel.
We are already witnessing a rise in vaccine preventable diseases, complications of pregnancy, and untreated chronic diseases as access to primary medical care disappears. The major industries of Liberia, Sierra Leone and Guinea are suffering and unemployment is now a problem throughout the region. The events in West Africa are a tragic illustration of how investment in public health and health care is an inextricable component of development, and how global disparities in health care resources are both a human rights issue and a threat to global health security.
Provided by Drexel University
Tuesday, July 29, 2014
5 things to know about Ebola outbreak in W. Africa
In this photo taken on Sunday, July 27, 2014, a boy, center, selling soft drinks walk past a clinic taking care of Ebola patients in the Kenema District on the outskirts of Kenema, Sierra Leone. Liberia President Ellen Johnson Sirleaf has closed some border crossings and ordered strict quarantines of communities affected by the Ebola outbreak. The announcement late Sunday came a day after Sirleaf formed a new taskforce charged with containing the disease, which has killed 129 people in the country and more than 670 across the region.(AP Photo/ Youssouf Bah)
29 july 2014—There has been panic and fear about the deadly Ebola disease spreading ever since Nigerian health officials reported Friday that a Liberian man sick with the disease had traveled to Togo and then Nigeria before dying. Here are five things to know about Ebola and how it is spread:
1. THE WEST AFRICA EBOLA OUTBREAK IS NOW THE LARGEST IN HISTORY. The World Health Organization says more than 672 people have died from Ebola. A total of 1,201 cases had been reported as of last week in Guinea, Liberia and Sierra Leone. In addition, one Liberian man has died in Nigeria.
2. BUT SOME PEOPLE HAVE SURVIVED EBOLA. While the fatality rate for Ebola can be as high as 90 percent, health officials in the three countries say people have recovered from the virus and the current death rate is about 70 percent. Those who fared best sought immediate medical attention and got supportive care to prevent dehydration even though there is no specific treatment for Ebola itself.
3. EBOLA CAN LOOK A LOT LIKE OTHER DISEASES. The early symptoms of an Ebola infection include fever, headache, muscle aches and sore throat, according to the World Health Organization. It can be difficult to distinguish between Ebola and the symptoms of malaria, typhoid fever or cholera. Only in later stages do people with Ebola begin bleeding both internally and externally, often through the nose and ears.
4. EBOLA IS ONLY SPREAD THROUGH BODILY FLUIDS. The Ebola virus is not airborne, so people would have to come into contact with the bodily fluids of an infected person. These include blood, sweat, vomit, feces, urine, saliva or semen—making transmission through casual contact in a public setting unlikely.
5. FEAR AND MISINFORMATION THOUGH IS MAKING THINGS WORSE. In each of the affected countries, health workers and clinics have come under attack from panicked residents who mistakenly blame foreign doctors and nurses for bringing the virus to remote communities. Family members also have removed sick Ebola patients from hospitals, including one woman in Sierra Leone's capital who later died. Police had to use tear gas to disperse others who attacked a hospital in the country.
