Back in late September, the press had a field day with a mathematical model developed by CDC that estimated that if left unchecked, the Ebola outbreak in West Africa could wind up infecting over 1.4 million people. Almost missed in the hysteria over that high number was the fact that this same model predicted that even with key public health measures (patient isolation, monitoring of at-risk population who had contact with infected people and safe burial practices) falling short of 100% implementation, the outbreak could be brought under control around January of next year.
Word has been leaking out for a while now that the rate of new Ebola infections in Liberia is falling. Reports in the Washington Post on October 29 and November 3 told us as much. A chart in the WHO Situation Report for November 5 drives home just how dramatic the decline in new cases has become:
As can be seen in the chart, the rate of new infections for the two most recent weeks is less than one fourth the rate at the peak of the outbreak. Unfortunately, the news for Sierra Leone is not as good. While the rate of new infections may be leveling off, it is not yet falling appreciably:
Digging into the WHO report a bit further, we can find some evidence for how this dramatic drop in new cases has been brought about. We see that 52% of cases are now isolated. The WHO target for December 1 has been set at 70%, with a target of 100% by January 1. When it comes to management of dead bodies, though, the December 1 target has already been surpassed. WHO reports that 87% of the dead are being “managed in a safe and dignified manner” while the targets were set at 70% for December 1 and 100% for January 1. Also, although no benchmarks are reported, WHO states that 95% of registered contacts were reached daily (although in the text of the report, there are suggestions this number may be somewhat overstated).
It should come as no surprise that progress in implementing these basic measures has had a huge impact on bringing down the rate of new infections. It fits perfectly with the CDC mathematical model and it also addresses the known biology of Ebola infections. Patients are most infectious at or near death, so establishing safe burial practices is vitally important. Conversely, identifying infected individuals through daily monitoring of the at-risk population and then isolating infected individuals once symptoms begin means that far fewer people are exposed to people producing large amounts of virus.
Sadly, those who remain exposed are the health care workers who are providing care to those who are infected. Despite shortages of equipment and supplies, WHO and other organizations are doing their best to overcome those shortages and to beef up training to reduce risk to these brave people on the front lines in the work to control the virus. As of this November 5 report, 546 health care workers have been infected, with 310 of them dying. Only four new infections were reported for the week ending November 2, so it is hoped that this rate is also dropping.
Had the alarmists who insisted that this was a new super-strain of Ebola capable of airborne transmission (or even a strain developed in a bioweapons laboratory), it is doubtful that these basic public health measures would have had such a dramatic impact on the rate of new infections. Perhaps those folks can go back to railing about chemtrails or the evils of vaccines, because basic boring science appears to be on the road to controlling the current outbreak before all of mankind succumbs.
In the meantime, we are at about two weeks into the three week incubation period both for anyone “exposed” by Craig Spencer or for Kaci Hickox (or anyone she “exposed”) to show symptoms. No reports of transmission so far, and the odds of any cases showing up are dropping very rapidly from the already very low levels where they started.
I’m either a lone voice in the wilderness or just another angry old man shouting at clouds on this, but, to me, the issue of personnel flow inside a facility treating a patient for Ebola is critical. Texas Health Presbyterian Dallas got that issue terribly wrong in the case of Thomas Duncan, and now, although they provide very good guidance on the issue of personal protective equipment and its use, new guidelines just released by CDC sadly fall short of correcting the problem I have highlighted.
The issue is simple and can even be explained on a semantic level. If a patient is being treated in an isolation ward, that isolation should apply not only to the patient but also to the staff caring for the patient. As I explained previously, National Nurses United complained that health care workers at Texas Health Presbyterian Dallas treated Duncan and then continued “taking care of other patients”.
Allowing care providers to go back to treating the general patient population after caring for an isolated patient is in direct contradiction to one of the basic recommendations by WHO in a document (pdf) providing guidance for treatment of hemorrhagic fever (HF, includes Ebola):
Exclusively assign clinical and non-clinical personnel to HF patient care areas.
By exclusively assigning personnel to care of the isolated patient, then the isolation is more complete.
The new CDC guidelines, released on Monday, offer updated recommendations on the types of personal protective equipment (PPE) to be used and how it is to be used. The guidelines also stress the importance of training on effective PPE use prior to beginning treatment of an Ebola patient. Unfortunately, though, the guidelines still leave open the possibility of health care workers moving between the isolation area and the general patient population.
In the preparations before treatment of an Ebola patient commences, the guidelines state:
Identify critical patient care functions and essential healthcare workers for care of Ebola patients, for collection of laboratory specimens, and for management of the environment and waste ahead of time.
And then once treatment begins, we have this:
Identify and isolate the Ebola patient in a single patient room with a closed door and a private bathroom as soon as possible.
Limit the number of healthcare workers who come into contact with the Ebola patient (e.g., avoid short shifts), and restrict non-essential personnel and visitors from the patient care area.
So the facility is advised to identify the “essential” workers who will provide care to an Ebola patient and to limit the number of personnel coming into contact with the patient. And even though the patient is to be in an isolated room, the guidelines still fall short of the WHO measure of calling for the Ebola treatment staff to be exclusively assigned. Precautions for safely removing the PPE are described, but once removed, the workers presumably are free to go back to mixing with the general patient population. Hospitals are cautioned against allowing large numbers of care providers into the room and to avoid “short shifts”, but there still is no recommendation for workers to be exclusively assigned to the isolation area.
The first thing that comes to mind in this regard is to question whether the CDC recommendations fall short of the WHO call for exclusive assignment in order to allow US hospitals avoid the perceived expense of dedicating a handful of personnel to treatment of a single patient. Is the ever-constant push to reduce personnel costs responsible for this difference between CDC and WHO guidelines? In the US healthcare system, it appears once again that MBA’s can carry more weight than MD’s on critical issues.
The incompetence of Texas Health Presbyterian Hospital Dallas is staggering. In following today’s rapidly developing story of a second nurse at the hospital now testing positive for Ebola, this passage in the New York Times stands out, where the content of a statement released by National Nurses United is being discussed (emphasis added):
The statement asserted that when Mr. Duncan arrived by ambulance with Ebola symptoms at the hospital’s emergency room on Sept. 28, he “was left for several hours, not in isolation, in an area where other patients were present.” At some point, it said, a nurse supervisor demanded that Mr. Duncan be moved to an isolation unit “but faced resistance from other hospital authorities.”
The nurses who first interacted with Mr. Duncan wore ordinary gowns, three pairs of gloves with no taping around the wrists, and surgical masks with the option of a shield, the statement said.
“The gowns they were given still exposed their necks, the part closest to their face and mouth,” the nurses said. “They also left exposed the majority of their heads and their scrubs from the knees down. Initially they were not even given surgical bootees nor were they advised the number of pairs of gloves to wear.”
The statement said hospital officials allowed nurses who interacted with Mr. Duncan at a time when he was vomiting and had diarrhea to continue their normal duties, “taking care of other patients even though they had not had the proper personal protective equipment while providing care for Mr. Duncan that was later recommended by the C.D.C.”
From the context of both the New York Times article and the nurses’ statement, it seems most likely that this movement of nurses from treating Duncan to treating other patients took place during the period after Duncan was admitted to the hospital and before the positive test result for Ebola was known. However, from the nurses’ statement showing that at least some of the personnel on duty realized Duncan almost certainly had Ebola, proper isolation technique should have been initiated immediately.
And that movement of nurses from a patient who should have been in isolation back into the general patient population is a huge, and obvious, error. Consider this publication (pdf) put out in August by the World Health Organization, summarizing precautions to be taken in care of Ebola patients. The very first page of actual content, even before the section labeled “Introduction”, is a page with the heading “Key messages for infection prevention and control to be applied in health-care settings”. The page lists nine bullet points about dealing with ” hemorrhagic fever (HF) cases” (hemorrhagic fever diseases include Ebola). Here is the third entry on that list:
Exclusively assign clinical and non-clinical personnel to HF patient care areas.
There really is no point in saying a patient is isolated if staff are freely moving back and forth between the isolation area and the general patient population. I’m wondering how long it will be until there is a whole new management team at Texas Health Resources, the parent firm for the hospital.
Although not yet widespread, panic and disinformation are emerging surrounding the case of the first patient to have been diagnosed with Ebola while in the United States. The worst of the hysteria surrounds the fact that Thomas E. Duncan flew from Liberia to the United States on a trip that required 28 hours, ending at the Dallas-Fort Worth airport on September 20. It is known that Duncan was screened in Liberia and found not to have a fever when he boarded the first flight. Persons infected with Ebola but not yet exhibiting symptoms are incapable of spreading the disease, primarily because the disease spreads through direct contact of mucous membranes or open wounds with bodily fluids and symptom-free patients are not yet vomiting or having diarrhea, so no virus-carrying fluids are being produced or at risk of being spread in ways that other people will come into contact with them.
On Tuesday, the Director of the CDC, Dr. Tom Frieden, stated outright that there is zero risk to passengers who were on a flight with Duncan:
A national public health official today said there was “zero risk of transmission” of Ebola on a commercial airline flight that a Dallas patient who has tested positive for the disease flew on from Liberia earlier this month.
Centers for Disease Control and Prevention Director Tom Frieden said today in a live briefing from Atlanta that the person — a male who remained unnamed — showed no symptoms before boarding the plane and was not contagious. The CDC doesn’t “believe there is any risk to anyone who was on the flight at that time,” he said.
Despite Frieden’s clear statement that other passengers face no risk, the press continued to hound CDC and the airlines until Duncan’s itinerary was released. While CBS was moderately responsible in their coverage of the flight information, the Daily Mail asked breathlessly in their headline whether YOU were on a flight with Duncan. Even more incredibly, stocks in US airlines were dumped yesterday in response to the news of Duncan’s flights:
Investors were also selling stocks following news that the first case of Ebola had been diagnosed in the U.S. Investors dumped airline stocks and bought a handful of drug companies working on experimental Ebola treatments.
The story of just how Duncan became infected is a sad one. On September 15 (recall that he left Liberia on the 19th and arrived in Dallas the 20th), Duncan helped neighbors take their 19-year-old daughter to the hospital. Sadly, the hospital was already overwhelmed with patients and she was turned away, only to die early the next morning after returning:
In a pattern often seen here in Monrovia, the Liberian capital, the family of the woman, Marthalene Williams, 19, took her by taxi to a hospital with Mr. Duncan’s help on Sept. 15 after failing to get an ambulance, said her parents, Emmanuel and Amie Williams. She was convulsing and seven months pregnant, they said.
Turned away from a hospital for lack of space in its Ebola treatment ward, the family said it took Ms. Williams back home in the evening, and that she died hours later, around 3 a.m.
Mr. Duncan, who was a family friend and also a tenant in a house owned by the Williams family, rode in the taxi in the front passenger seat while Ms. Williams, her father and her brother, Sonny Boy, shared the back seat, her parents said. Mr. Duncan then helped carry Ms. Williams, who was no longer able to walk, back to the family home that evening, neighbors said.
The hospital in Dallas where Duncan is being treated has received a lot of criticism because he first went there on September 26 but was sent home when only exhibiting a low grade fever:
When Mr. Duncan first arrived at the hospital last Friday, six days after he had arrived in America, he told a nurse that he had come from West Africa. Public health officials have been urging doctors and nurses to be on the alert for Ebola in anyone who has been in Guinea, Liberia or Sierra Leone. But information about Mr. Duncan’s travel was not “fully communicated” to the full medical team, said Dr. Mark Lester, executive vice president of Texas Health Resources, the parent organization that oversees Texas Health Presbyterian Hospital.
As a result, that information was not used in the clinical diagnosis and Mr. Duncan was sent home, with the diagnostic team believing he simply had a low-grade fever from a viral infection, Dr. Lester said.
Those with whom Duncan had contact from the time of the onset of his symptoms until he returned the hospital on September
30 28 (corrected; September 30 was when tests confirmed Ebola after he returned to the hospital on September 28) in much worse condition and was then isolated are being monitored for signs that they may be infected:
Officials said Wednesday that they believed Mr. Duncan came into contact with 12 to 18 people when he was experiencing active symptoms and when the disease was contagious, and that the daily monitoring of those people had not yet shown them to be infected.
The incubation period (the time between exposure to the disease and the onset of symptoms in an infected person) for Ebola varies from 2 to 21 days. Recall that Duncan was exposed on September 15 and visited the hospital for the first time on September 26, so his incubation period was around eleven days. We are now around six days into the time since Duncan first visited the hospital, so those with whom he came into contact will need to be monitored for for another two weeks or so until at least 21 days have passed since their last contact with Duncan.
While there is some chance that one or more of those with whom Duncan had contact while he was contagious will become infected, as long as everyone who was in contact with him during that critical period is under observation now, there is virtually no chance of the disease spreading outside that small group of people. And you can rest assured that nobody from any of the flights Duncan was on will come down with disease from exposure to him.
As the Ebola outbreak in West Africa continues to grow, fresh attention was focused on it yesterday when the CDC announced that in a mathematical model they developed of the outbreak, failing to intervene in spread of the virus could lead to as many as 1.4 million people infected by late January. Somewhat lost in the response to the “wow factor” of a projection of over a million people being infected is that the model also very powerfully demonstrates how the viral outbreak can be contained simply through moderate adoption of the most basic aspects of an infection control program.
The key to preventing spread of the virus is for those who care for infected patients, whether they are health care workers at a hospital or family members in the home, is preventing contact with fluids from the patient. CDC has prepared an informative guidance document for how health care workers can control the spread of Ebola in their facilities. The key steps are to provide protective clothing to cleaning staff, use an effective disinfectant, avoid re-use of materials with pourous surfaces and dispose (as regulated medical waste) of all textiles, linens, pillows and mattresses that may be contaminated.
Because practices such as these are routinely implemented in US health facilities when patients with high risk infectious diseases are being treated, there is little to no chance of Ebola spreading within the US. As noted in the previous Ebola post, the extreme poverty of the health care systems in the affected countries in Africa is what has allowed the disease to spread, as health care facilities there simply cannot afford the materials they need for implementing safe practices.
Here is the output of the model for Ebola spread in Liberia and Sierra Leone if infection control is not implemented beyond the current level. As noted in the NYTimes article linked above, the current estimate is that 18% of patients in Liberia and 40% of patients in Sierra Leone are treated in facilities that prevent spread of the virus. The model predicts both the number of infected patients in the two countries and the number of beds devoted to care of those patients (“corrected” means that the estimate for number of infected individuals is corrected for the assumption that 2.5 times more patients are infected than have been officially reported):
As noted above and widely cited in the press yesterday, if the virus outbreak is left unchecked, the model predicts a cumulative total 1.4 million infected patients in the two countries by January 20 (many of whom are dead by then) and a need for up to 100,000 beds for treatment of these patients.
The good news that is buried in the CDC model is that stopping the virus outbreak does not require implementation of virus control measures for treatment of every infected patient. In the graphs below, we see the output from the model under the assumption that viral control practices start to be implemented now and expand to a level of 70% of infected patients (25% of them in hospitals and 45% in home treatment) being treated under safe practices by December:
Note that the cumulative number of cases levels off between 25,000 and 30,000 and the total number of beds needed peaks at around
13,000 1300 before dropping rapidly.
This model demonstrates very clearly that the highest priority for stopping the Ebola outbreak should be rapid and widespread implementation of basic infection control practices. Spreading this information into homes where patients are being treated is key. Convincing families of the importance of removing infected clothing and bedding seems likely to be the pivotal aspect of the public information campaign. Help from the West will be essential in providing the huge amount of disposable protective clothing and the necessary cleaning and disinfecting supplies. Replacement clothing, linens, mattresses and pillows should be provided as many of the affected families will be hard-pressed to replace these items under the already difficult conditions of an infected family member.
Further good news is that these projections were based on conditions in August and there is reason to believe that the situation may already be getting better. From the Times, again:
The caseload projections are based on data from August, but Dr. Thomas R. Frieden, the C.D.C. director, said the situation appeared to have improved since then because more aid had begun to reach the region.
“My gut feeling is, the actions we’re taking now are going to make that worst-case scenario not come to pass,” Dr. Frieden said in a telephone interview. “But it’s important to understand that it could happen.”
Let’s hope that Dr. Frieden is correct.
Recall that last fall, Barack Obama spent some time altering the public record on when CIA-trained death squads first entered Syria to move the date from just before the Ghouta sarin attack to just after (while also trying to shrink the size of those first groups). But the US was a month behind Pakistan’s Taliban, who also sent fighters to Syria, ostensibly on the same side as us this time, to fight pro-Assad forces. But while these efforts on the same side in Syria are having little success as Assad remains in power and might even be gaining the upper hand, the work of the CIA and Taliban on opposite sides in Pakistan has produced a devastating result, with the World Health Organization announcing yesterday that it has declared a Public Health Emergency of International Concern over the spread of polio to countries where it previously had been eradicated:
After discussion and deliberation on the information provided, and in the context of the global polio eradication initiative, the Committee advised that the international spread of polio to date in 2014 constitutes an ‘extraordinary event’ and a public health risk to other States for which a coordinated international response is essential. The current situation stands in stark contrast to the near-cessation of international spread of wild poliovirus from January 2012 through the 2013 low transmission season for this disease (i.e. January to April). If unchecked, this situation could result in failure to eradicate globally one of the world’s most serious vaccine preventable diseases. It was the unanimous view of the Committee that the conditions for a Public Health Emergency of International Concern (PHEIC) have been met.
Although fundamentalist Islamic groups have long accused vaccination campaigns, and especially polio vaccinations, of being efforts by the West to sterilize Muslims, the very high profile case of Dr. Shakeel Afridi carrying out a hepatitis vaccination ruse on on behalf of the CIA in an effort to obtain blood samples from Osama bin Laden’s compound in Abbottabad provided a refreshed incentive for attacks on vaccine programs.
Marcy pointed out the stupidity of Leon Panetta’s confirmation that Afridi worked with the CIA in the ruse the day before Panetta’s 60 Minutes segment ran:
Not only does this presumably put more pressure on Pakistan to convict Afridi of treason (he remains in custody), but it exacerbates the problem of having used a vaccination campaign as cover in the first place, confirming on the record that similar campaigns in poor countries might be no more than a CIA front.
I presume someone in the White House gave Panetta permission to go blab this on 60 Minutes; I assume he’s in no more legal jeopardy than Dick Cheney was when he insta-declassified Valerie Plame’s identity.
But shit like this discredits every single claim national security experts make about the need for secrecy. I mean, how are CIA officers ever going to recruit any more assets when the assets know that the CIA director may, at some time in the future that’s politically convenient, go on 60 Minutes and confirm the relationship?
Afridi was eventually sentenced to 30 years imprisonment, not on treason but on other dubious charges and in a shopped venue. And the fallout in Pakistan’s tribal areas from US confirmation of the vaccination ruse was exactly as might be expected: multiple deadly attacks on polio vaccine workers and many new cases of paralyzed children.
While the polio virus circulating in Syria doesn’t appear to have come directly with the Taliban fighters sent from Pakistan, it is indeed a strain from Pakistan’s tribal areas that is in Syria now:
Thirteen cases of wild poliovirus type 1 (WPV1) have been confirmed in the Syrian Arab Republic. Genetic sequencing indicates that the isolated viruses are most closely linked to virus detected in environmental samples in Egypt in December 2012 (which in turn had been linked to wild poliovirus circulating in Pakistan).
WHO is recommending drastic measures, primarily calling for all travelers from Pakistan, Cameroon and Syria to be vaccinated for polio, preferably at least four weeks prior to international travel, but at least at departure if it hasn’t been done earlier. WHO is also calling for increased efforts in vaccinations in countries (Afghanistan, Equatorial Guinea, Ethiopia, Iraq, Israel, Somalia and Nigeria) where the virus is known to be present but from which transmission has not been seen.
So the fears from two years ago on the impact of the CIA’s actions on polio eradication are now met. But keep in mind that it’s not just vaccine programs that were put at risk by this incredibly stupid move. A large alliance of humanitarian groups complained directly to the CIA that all humanitarian groups were put at risk by the move, since the CIA ruse was carried out under cover of a humanitarian organization. Will John Brennan be able to heed this advice?
Yesterday, we got the tremendous news that after having lead the world in the number of polio cases as recently as 2009, the World Health Organization announced that there have been zero polio cases in India for three consecutive years. In today’s Express Tribune, we see a discussion of whether and how Pakistan can now rise to the challenge of polio eradication. In the article, we learn that the US drone killing of Pakistan Taliban leader Hakimullah Mehsud not only disrupted the developing plans for peace talks between the Taliban and Pakistan’s government, but it also affected polio vaccinations in North and South Waziristan:
According to the State Minister for National Health Services, Regulations and Coordination Saira Afzal Tarrar, NWA and South Waziristan did not receive any immunisation in months, contrary to former North Waziristan Agency (NWA) surgeon Jan Mir Khan, who was part of recent polio efforts. “After the drone strike that killed Hakimullah, it all stopped. Not just the peace talks, but also our efforts,” she says.
The terrible impact of the CIA’s vaccination ruse employing Dr. Shakeel Afridi in the search for Osama bin Laden has been extensively documented here, but this is the first time I have seen a suggestion that backlash to a drone strike directly resulted in polio vaccines being denied to children. Tarrar is not ready to give up, however, and believes that Pakistan and the Taliban will eventually come to an agreement that will allow vaccinations to resume:
Saira Tarrar also emphasised that the people of the area need to be part of the solution. “Parents are now sick of the ban; this pressurises the Taliban.”
“There is an accessibility problem in Fata, but by 2014, we will get a bargain and get some access.” And access is key, as far as Elias Durray, the head of Polio Eradication at the World Health Organization in Pakistan is concerned. “Immunisation prevents circulation. The virus won’t vanish on its own.”
Let us hope that Pakistan can achieve full vaccine coverage and have polio disappear as quickly in Pakistan as it did in India. Of course, this will require the US actually letting peace negotiations between the Taliban and Pakistan come to fruition, so success is far from guaranteed.
There are public calls on a remarkable number of different fronts for a renewed commitment to polio vaccination in the Khyber Pakhtunkhwa province of Pakistan, which is now governed by Imran Khan’s PTI party. Direct appeals to Khan are coming from the World Health Organization and from Bill Gates. A major conference of Islamic scholars also came out with a statement backing polio immunization and providing push-back against the view that immunization campaigns aim to sterilize Muslims or are run by Western intelligence agencies.
Dawn gives us the details of the WHO push:
World Health Organisation, Pakistan polio chief Dr Elias Durry on Thursday apprised Pakistan Tehreek-i-Insaf chairman Imran Khan in Lahore of the threat to the health of Khyber Pakhtunkhwa children due to non-vaccination, it is learned. PTI, which has the most seats in the Khyber Pakhtunkhwa Assembly, leads a coalition government in the province.
According to the relevant officials, the meeting has coincided with the confirmation of three fresh polio cases from Federally Administered Tribal Areas by National Institute of Health.
They said Fata had reported five, Khyber Pakhtunkhwa four and Sindh two of this year’s 13 countrywide polio cases.
Khan is eager to help in the campaign and has taken part in promoting immunization before his party was elected to govern KP:
The officials said WHO had publicly recorded its reservations about polio eradication efforts in Khyber Pakhtunkhwa, especially in Peshawar.
They said the PTI chairman, who had inaugurated various polio campaigns in the country’s several cities, apprised the WHO, Pakistan polio chief of his eagerness to see fight against polio succeed.
The officials said Imran Khan carefully listened to Dr Elias Durry’s concerns about Khyber Pakhtunkhwa children’s vaccination and assured him that he would convey them to the PTI-led provincial government for necessary action on emergency basis.
“Imran Khan said he would issue special instructions to the provincial chief minister (who belongs to PTI) to ensure vaccination of all children under five as ensuring better health care in the province is his government’s top priority,” an official said.
Also joining the push for immunization is Bill Gates, as we learn from the Express Tribune:
Famous American business magnate Bill Gates has sought Imran Khan’s cooperation to eradicate polio in Khyber-Pakhtunkhwa, as the province apparently failed to provide security to polio workers.
Gates sent a personal letter through his emissary to chairman Pakistan Tehreek-e-Insaf (PT) Imran Khan asking for his party’s cooperation in furthering the anti polio vaccination programme in Khyber Pakhtunkhwa, said an official statement.
Imran Khan is scheduled to speak to him on the phone to discuss modalities of moving against polio which takes the lives of so many children in Pakistan especially in Khyber Pakhtunkhwa.
Especially welcome news comes from a meeting held by Islamic scholars who produced a statement in favor of immunization and condemning the killing of vaccination workers. They also condemned Dr. Shakil Afridi and any other participation of intelligence agencies in vaccination programs: Continue reading
With the winter flu season now over in the Northern Hemisphere, we can safely say that the feared global pandemic from the newly emerged H7N9 flu virus did not occur. As the weather in China warms up, cases are dwindling in the manner usually seen for any flu virus:
After months of mounting concern, Chinese health officials are breathing a sigh of relief: no new human cases of H7N9 have been reported in the country in more than a week. The milestone marks the first time since March, when the H7N9 outbreak first began, that human cases haven’t continued to increase.
In the week beginning May 13, one previously infected patient succumbed to the virus, according to a statement issued on Monday by China’s National Health and Family Planning Commission. That death brings the H7N9 fatality toll to 36, with 130 confirmed cases in total.
Vigilance will be needed next fall to see if the virus is now lurking, ready to re-emerge once weather conditions are more favorable.
Unfortunately, the situation with another emerging virus is not improving. The newly named (pdf) Middle East Respiratory Syndrome Coronavirus (MERS-CoV) still bears watching since the death toll from this virus has now reached 30:
Three more people have died in Saudi Arabia from the new SARS-like coronavirus, bringing the worldwide death toll to 30, the World Health Organization (WHO) said on Friday.
Saudi health officials also told the WHO of a new case in the eastern province of al-Ahsa, increasing the number of cases worldwide to 50, WHO spokesman Glenn Thomas told reporters at a news conference in Geneva.
As shown in the schematic above, coronaviruses get their name from the crown-like spikes on their surface. The common cold is caused by various members of the coronavirus family.
Another coronavirus that got headlines in the past was the virus causing Severe Acute Respiratory Syndrome, or SARS. That virus was first identified in 2003. This otherwise informative description of the virus and its outbreak that resulted in over 8000 cases and 750 deaths states that SARS is “here to stay”, but the CDC, in this backgrounder on coronaviruses, notes that there have been no reported cases of SARS since 2004.
From the link above where MERS-CoV was given its new name, we get more information on the virus (references removed): Continue reading
A steady, but slow and at least for now, not accelerating, spread of the new H7N9 bird flu virus continues. Although infection of poultry in markets in Shanghai has been confirmed and thousands of birds culled, ongoing work on the virus has yet to provide what appears to be a full description of how the virus spreads in animal hosts and gets transmitted to humans.
The latest figures from China put the death toll at 9 and the number of confirmed cases at 28 people infected. The question of whether the virus can be passed from one person to another is still under intense investigation, and two possible family clusters are being investigated. WHO spokesman Gregory Hartl was quoted by Xinhua:
“At this point, there is no evidence of sustained human to human transmission,” he said, adding that there are some “suspected but not yet confirmed cases of perhaps very limited transmission between close family members.”
“They are still being investigated,” he said.
Hartl told Xinhua one of the suspected family clusters was in Shanghai, with three family members having similar symptoms and one of them being confirmed of H7N9.
The confirmed case died, so has another suspected family member, according to Hartl.
The other suspected family cluster, which included two family members with one of them being confirmed, was in Jiangsu Province, he said.
Hartl said that even if the infection of H7N9 is confirmed in other family member, further investigations are still needed to make sure whether that’s a human to human transmission between constant and close contacts or an infection with virus from the same environmental source.
That final point from Hartl illustrates the difficulties that scientists face in developing a full description of how the disease is transmitted. At the same time that we do not yet know fully which animals are the reservoir from which humans are infected, we are simultaneously trying to determine whether family members are passing the virus to one another. That question is complicated by the fact that because the family members live in close proximity to one another but by definition also are exposed to the same local environment, multiple family members could have been infected from the same animal source or one family member could have passed the disease to another.
Moving to the question of the animal host, the same Xinhua article that quotes Hartl also informs us that no pigs have been found to be infected with the virus. Recall that large numbers of pig carcasses had been disposed of in rivers in the same areas of China around the same time H7N9 emerged, so some scientists wondered whether the virus arose in pigs and caused those deaths. There were also observations of dead birds. Xinhua has new information on analysis of bird infections: Continue reading