Sunday, April 23, 2017

Community Pandemic Mitigation's Primary Goal : Flattening The Curve














#12,404


When the next influenza pandemic virus emerges and begins to spread around the world, the CDC, HHS, WHO and other partners will work to contain the outbreak at its source (if possible), to slow its spread internationally (again, if possible), and begin to work on a vaccine.
A vaccine - while viewed as the best response to a pandemic, will take time. How much time, will depend on a lot of factors.
Despite improved vaccine manufacturing technologies, we would have to get very lucky to have any significant quantity of vaccine available for the general public in less than six months.

A novel virus may require 2 shots - a month apart - to invoke an adequate immune response, and that assumes an effective vaccine can be made at all.
Add in the inevitable global scramble for a limited supply of any vaccine, the logistics of deploying said vaccine to billions of people in a short period of time . . .   and well - the TV and movie cliche where some valiant scientist creates, tests, and distributes a vaccine in the nick of time is a pretty optimistic scenario.

This isn't to dismiss the importance of a vaccine.  Pandemics tend to come in waves.  The 1918 pandemic - which killed between 50 and 100 million people - came in three distinct waves, over an 18 month period. 
Even if a vaccine isn't available for the first wave, it could save millions of lives in the waves that follow.
But until a vaccine is widely available, the goal is to slow the spread of a pandemic virus, to limit its impact, and to try to save as many lives as possible through the use of NPIs - Nonpharmaceutical Interventions.
 
The CDC’s Nonpharmaceutical Interventions (NPIs) webpage defines NPIs as:
Nonpharmaceutical interventions (NPIs) are actions, apart from getting vaccinated and taking medicine, that people and communities can take to help slow the spread of illnesses like influenza (flu). NPIs are also known as community mitigation strategies.

While some may scoff at their effectiveness, we have a real-world example during the worst flu pandemic in recorded history  - the 1918 Spanish flu.



The chart above, taken from the PNAS journal article entitled Public Health Interventions and Pandemic Intensity During the 1918 Influenza Pandemic, illustrates what happened in two American cities during the 1918 pandemic. 
  • The sharp, but much shorter pandemic wave depicted by the solid line occurred in Philadelphia, where relatively few steps were taken by the public health department to slow the spread of the disease (they even ok'd a massive Liberty Loan parade on September 28th).   
  • The dotted line represents St. Louis, which closed schools early and where the Health Department prohibited public gatherings in places like theaters, churches, and restaurants. 
As you can see, the percentage of cases reported on a daily basis were far fewer in St. Louis, but their pandemic wave lasted nearly twice as long as in Philadelphia. 
 
At its worst, the percentage of excess of people afflicted in the city of Philadelphia was 5 times greater than what St. Louis experienced. The burden on hospitals, mortuaries, and practically all segments of the economy was certainly far greater.  
None of this is a new concept, and we were discussing these issues 10 years ago when the previous Community Mitigation Guidelines were released.

This is why the primary goal of the HHS/CDC's 2017 revised Community Mitigation Guidelines to Prevent Pandemic Influenza - which we've already looked at twice yesterday (see here, and here)is to slow the spread of any pandemic outbreak, in hopes of limiting its impact on hospitals, essential workers, infrastructure, and ultimately reducing the death toll. 

An excerpt from the summary reads:

Purpose

The purpose of these guidelines is to help state, tribal, local, and territorial health departments with prepandemic planning and decision-making by providing updated recommendations on the use of NPIs. 

These recommendations have incorporated lessons learned from the federal, state, and local responses to the influenza A (H1N1)pdm09 virus pandemic (hereafter referred to as the 2009 H1N1 pandemic) and findings from research. Communities, families and individuals, employers, and schools can create plans that use these interventions to help slow the spread of a pandemic and prevent disease and death.

Specific goals for implementing NPIs early in a pandemic include slowing acceleration of the number of cases in a community, reducing the peak number of cases during the pandemic and related health care demands on hospitals and infrastructure, and decreasing overall cases and health effects ( Figure 1).
When a pandemic begins, public health authorities need to decide on an appropriate set of NPIs for implementation and to reiterate the importance of personal protective measures for everyday use (e.g., voluntary home isolation of ill persons [staying home when ill], respiratory etiquette, and hand hygiene) and environmental cleaning measures (e.g., routine cleaning of frequently touched surfaces), which are recommended at all times for prevention of respiratory illnesses ( Table 1).

Personal protective measures reserved for pandemics (e.g., voluntary home quarantine of exposed household members [staying home when a household member is ill] and use of face masks by ill persons) also might be recommended (Table 1). A more difficult decision is how and when to implement community-level NPIs that might be warranted but are more disruptive (e.g., temporary school closures and dismissals, social distancing in workplaces and the community, and cancellation of mass gatherings) (Table 1).

These decisions are made by state and local officials on the basis of conditions in the applicable jurisdictions, with guidance from CDC (according to pandemic severity and potential efficacy) and governing authorities (1). Prepandemic planning, along with community engagement, is an essential component of these decisions ( Table 2).
         (Continue . . . .)



Although there may be other pharmaceutical options - like antivirals - available at the start of a pandemic, those will be in finite supply and are not a panacea for infection.  Prevention is always better than treatment, but never more so than during a pandemic, when treatment options may quickly become limited.

Hospital beds, ventilators, even hospital staff - may all be in short supply during a pandemic (nurses get sick, too) - which makes it all the more imperative we flatten the curve - even if it means extending the duration of a pandemic wave.

While telling people to wash their hands, cover their coughs, avoid crowds, and stay home while sick may seem like a weak response to a pandemic - in truth, they (and other more disruptive measures like school closures, cancellation of public events, etc.) may be our most powerful weapons in any pandemic.
But they must be properly applied, else they could do more harm than good.
It's neither practical or desirable to simply shut everything down at the first sneeze, and try to wait out what could be a year (or longer) pandemic. Very few are equipped to do so, and besides, someone has to keep the lights on, deliver the food, refine the fuel, police the streets,  take care of the sick and injured . . . and do the thousands of other things that hold civilization together.
We'll have to find ways to live and work as safely as possible during a pandemic. Else the virus could quickly become the least of our problems.

Which is the point of these new guidelines. A severe pandemic will require some difficult, and likely unpopular, decisions on the part of public health and government officials. If those decisions were easy, or clear cut, I suspect it wouldn't take near 160 pages to help explain the scientific rationale behind them.  
It's not an exact science, and no one should expect that all will go smoothly during a pandemic, even with these new guidelines.
But at least we have the experience of the 2009 pandemic under our belts, along with 10 years of additional science, to augment and improve the previous set of guidelines. For a look as some of the research on NPIs over the past few years, you may wish to revisit:

Study: Effectiveness of NPIs Against ILI's

Michigan NPI Study: A Closer Look


Study: Efficacy Of Hand Hygiene Alone Against Influenza Infection
NPI’s and Influenza

Study: NPI's Can Help Prevent Spread Of Flu-Like Illnesses



Saturday, April 22, 2017

PSAF Is The New Pandemic Severity Index




















#12,403

In this, our first close look at the revised 2017 CDC/HHS Community Pandemic Mitigation Plan, published yesterday in the MMWR, we look at the new gauge of pandemic intensity; the PSAF (Pandemic Severity Assessment Framework). 

The Pandemic Severity Index (see graphic below) was adopted in the 2007 Community Strategy for Pandemic Influenza Mitigation plan as a way to quantify the likely impact of any pandemic outbreak.  It was based on the initial CFR (Case Fatality Ratio) of the virus, and was modeled in many respects after the 5 category Saffir-Simpson wind scale used for hurricanes. 


While a familiar format to most Americans, it ran into some of the same problems during the 2009 pandemic that the Saffir-Simpson scale has run into with Hurricane Katrina in New Orleans, Superstorm Sandy in New York, and Hurricane Mathew along Florida's east coast.

A single metric (be it CFR or wind speed) doesn't always accurately predict the impact of a pandemic or a hurricane.

In 2009, early reports (where the most seriously ill are most likely to be identified) suggested an elevated case fatality rate. Not unexpectedly, people were taking that number, and multiplying it times 30% of the population, and coming up with horrendous death tolls (see Categorically Speaking).
And just as there can be a huge difference in damage between a Cat 3 hurricane hitting Miami (as Wilma did in 2005), and a Cat 3 hitting New Orleans (as Katrina did the same year), what may turn out to be a CAT 1 pandemic in Ottumwa, Iowa could well end up being a CAT 2+ pandemic in Mumbai, India.
A one size-fits-all rating, based on a single (easily misjudged) metric, can go quickly awry.  Add in the fact that pandemic viruses are constantly evolving, and what might start out as a mild pandemic could strengthen over time, while a severe pandemic might weaken greatly after the opening weeks or months.

What is needed is a more comprehensive and encompassing method of assessing a pandemic virus and predicting its likely impact. To that end, we have the PSAF.  

Pandemic Severity Assessment Framework (PSAF)
 
Assessing Pandemic Severity and Health Impact


When a novel influenza virus emerges that can spread easily and efficiently and cause a pandemic, CDC and partners must gauge its projected impact and recommend rapid action to reduce virus transmission, protect vulnerable population groups, and minimize societal disruption (5). Historically, the severity of influenza pandemics has been estimated by calculating case-fatality ratios.§§ However, as we learned during the 2009 H1N1 pandemic (Box 1), case-fatality ratios may be difficult to measure early in a pandemic because of care-seeking behavior and testing practices (i.e., not everyone will seek care for their illness, and not everyone will be tested and diagnosed with pandemic influenza). As a result, severe and fatal cases may be more likely to be reported, creating a bias.


Due to such limitations, reliance on any single measure of viral transmission or clinical outcomes is unlikely to provide an accurate estimate of the potential impact of an emerging pandemic. CDC has, therefore, developed a new assessment framework that uses multiple clinical and epidemiologic indicators to create a comprehensive picture of the potential impact of an emerging pandemic (3). As indicated in Tables 5 and 6, the Pandemic Severity Assessment Framework (PSAF) estimates pandemic severity (or health impact) by synthesizing multiple measurements of:

  •  Viral transmissibility, including school, workplace, and/or community attack rates, secondary household attack rates, school and/or workplace absenteeism rates, and rates of emergency department and outpatient visits for ILI.
  •  Clinical severity, including case-fatality ratios, case-hospitalization ratios, and deaths-hospitalizations ratios.
Additional PSAF data may be obtained by characterizing genetic markers in a pandemic virus and by conducting animal studies on its transmissibility and virulence.





No matter how well designed the algorithm, getting good numbers out of a formula requires plugging `good' numbers in. And getting those numbers - particularly through the `fog of flu' common in the early days of a pandemic - may not be possible.

But once reasonably accurate data becomes available, this method ought to provide us with a much better idea of what we are facing and must prepare for.

CDC/HHS Community Pandemic Mitigation Plan - 2017














#12,402


Just over 10 years (Feb. 1st, 2007), at a time when H5N1 was the hot pandemic topic, the CDC & HHS unveiled their 2007 Community Strategy for Pandemic Influenza Mitigation plan. This 108 page document covered a variety of topics, including the creation of a pandemic severity scale, and the expected role of NPI's (Non Pharmaceutical Interventions) in combating any pandemic outbreak (see The CDC Does NPI).
Two years later, the 2009 H1N1 pandemic erupted, and while not the virus (or the severity) originally feared, these guidelines provided an important set of tools for the incoming administration to use - particularly in the early days and weeks  of the outbreak. 
Fast forward a full decade, and with the experiences of a moderate pandemic under our belts, and a far more complex line up of novel flu viruses (H5N1, H5N8, H7N9, H5N6, H3N2v, H1N2v, H1N1v, etc) in play, the CDC/HHS has decided to revise and hone the previous document, and replace it with a 2017 Community Mitigation Guidelines to Prevent Pandemic Influenza.

The overview was published yesterday in the MMWR, and while lengthy, is but a fraction of the entire document.  When you add in the two supplemental documents, this new set of guidelines runs over 160 pages, starting with:

Community Mitigation Guidelines to Prevent Pandemic Influenza — United States, 2017 
Recommendations and Reports / April 21, 2017 / 66(1);1–34
Noreen Qualls, DrPH1; Alexandra Levitt, PhD2; Neha Kanade, MPH1,3; Narue Wright-Jegede, MPH1,4; Stephanie Dopson, ScD5; Matthew Biggerstaff, MPH6; Carrie Reed, DSc6; Amra Uzicanin, MD1 (View author affiliations)

This HTML version contains only about half of the full PDF file (https://www.cdc.gov/mmwr/volumes/66/rr/pdfs/rr6601.pdf).

The two supplemental documents are:

Published Date: April 21, 2017 
Source: Qualls N, Levitt A, Kanade N, et al. Community Mitigation Guidelines to Prevent Pandemic Influenza — United States, 2017. MMWR Recomm Rep 2017;66(No. RR-1):1–34.

         Published Date: April 21, 2017 
Source: Qualls N, Levitt A, Kanade N, et al. Community Mitigation Guidelines to Prevent Pandemic Influenza — United States, 2017. MMWR Recomm Rep 2017;66(No. RR-1):1–34.
If it sounds as if there is a lot to read and absorb here, you're right.   I've only just begun to dig into the details. Over the next week or two I hope to flesh out some of the highlights, and compare this new document to the old one.

A couple of months ago, in Probably Not The Worst Idea In The World . . ., we discussed how now might be a good time for businesses and agencies to take out their old pandemic plans, dust them off, and revise them as needed. 

Perhaps this latest release from the MMWR will help to inspire other entities - both public and private - to follow suit.



WHO Avian Flu Risk Assessment - April 2017

















#12,401



The World Health Organization has released an updated Influenza at the human-animal interface report - one that reflects H7N9 cases officially notified to WHO by the Chinese government through April 20th of this year, along with a single H9N2 infection reported in a child from Gansu Province, China. 
This report is dated April 20th, but since China doesn't always notify WHO immediately of cases, today's report is running roughly 30 behind Hong Kong's most recent tally. 
Two HPAI H5 viruses with a track record of infecting humans (H5N1 & H5N6) were not diagnosed during this latest reporting period, with only 2 H5N1 cases reported thus far in 2017, and the last human H5N6 infection reported last November in China.


First some excerpts from today's report, then I'll return with a bit more.

Influenza at the human-animal interface

Summary and assessment, 16 March to 20 April 2017

  • New infections1: Since the previous update, new human infections with influenza A(H7N9) and A(H9N2) viruses were reported.
  • Risk assessment: The overall public health risk from currently known influenza viruses at the human-animal interface has not changed, and the likelihood of sustained human-to-human transmission of these viruses remains low. Further human infections with viruses of animal origin are expected.
  • IHR compliance: All human infections caused by a new influenza subtype are required to be reported under the International Health Regulations (IHR, 2005).2 This includes any animal and non-circulating seasonal influenza viruses. Information from these notifications is critical to inform risk assessments for influenza at the human-animal interface.

Avian Influenza Viruses

 
Avian influenza A(H5) viruses

 
Current situation:
Since the last update, no new laboratory-confirmed human cases of influenza A(H5) virus infection were reported to WHO. Influenza A(H5) subtype viruses have the potential to cause disease in humans and thus far, no human cases, other than those with influenza A(H5N1) and A(H5N6) viruses, have been reported to WHO. According to reports received by the World Organisation for Animal Health (OIE), various influenza A(H5) subtypes continue to be detected in birds in Africa, Europe and Asia.


Avian influenza A(H7N9) viruses


Current situation: During this reporting period, 86 laboratory-confirmed human cases of influenza A(H7N9) virus infection were reported to WHO from China. Case details are presented in the table in the Annex of this document. For additional details on these cases, public health interventions, and the recently detected highly pathogenic avian influenza (HPAI) A(H7N9) viruses, see the Disease Outbreak News.


As of 20 April 2017, a total of 1393 laboratory-confirmed cases of human infection with avian influenza A(H7N9) viruses, including at least 534 deaths3, have been reported to WHO (Figure 1).


1 For epidemiological and virological features of human infections with animal influenza viruses not reported in this assessment, see the yearly report on human cases of influenza at the human-animal interface published in the Weekly Epidemiological Record. www.who.int/wer/en/
2 World Health Organization. Case definitions for the four diseases requiring notification in all circumstances under the International Health Regulations (2005). www.who.int/ihr/Case_Definitions.pdf

3 Total number of fatal cases is published on a monthly basis by China National Health and Family Planning Commission.

According to reports received by the Food and Agriculture Organization (FAO) on surveillance activities for avian influenza A(H7N9) viruses in China4, positives among virological samples continue to be detected mainly from live bird markets, and some commercial and backyard farms.

Risk Assessment

1. What is the likelihood that additional human cases of infection with avian influenza A(H7N9) viruses will occur? Most human cases are exposed to the A(H7N9) virus through contact with infected poultry or contaminated environments, including live poultry markets. Since the virus continues to be detected in animals and environments, further human cases can be expected. Additional sporadic human cases of influenza A(H7N9) in other provinces in China that have not yet reported human cases are also expected.
2. What is the likelihood of human-to-human transmission of avian influenza A(H7N9) viruses? Even though small clusters of cases have been reported, including those involving healthcare workers, currently available epidemiological and virological evidence suggests that this virus has not acquired the ability of sustained transmission among humans, thus the likelihood is low.

 
3. What is the risk of international spread of avian influenza A(H7N9) virus by travellers? Should infected individuals from affected areas travel internationally, their infection may be detected in another country during travel or after arrival. If this were to occur, further community level spread is considered unlikely as this virus has not acquired the ability to transmit easily among humans.
4 Food and Agriculture Organization. H7N9 situation update. www.fao.org/ag/againfo/programmes/en/empres/H7N9/situation_update.html

Avian influenza A(H9N2) viruses
Current situation:

 
One new laboratory-confirmed human case of A(H9N2) virus infection was reported to WHO from China in an eleven-month-old boy from Gansu province. The case developed mild illness on 6 February 2017, was hospitalized and has recovered. He had exposure to backyard poultry prior to illness onset. This is the first human case of avian influenza A(H9N2) virus infection reported to WHO since December 2016 and the first human case reported from Gansu province. Avian influenza A(H9N2) viruses are enzootic in poultry in China.

Risk Assessment:
1. What is the likelihood that additional human cases of infection with avian influenza A(H9N2) viruses will occur? Most human cases are exposed to the A(H9N2) virus through contact with infected poultry or contaminated environments. Human infection tends to result in mild clinical illness. Since the virus continues to be detected in poultry populations, further human cases can be expected.
2. What is the likelihood of human-to-human transmission of avian influenza A(H9N2) viruses? No case clusters have been reported. Currently available epidemiological and virological evidence suggests that this virus has not acquired the ability of sustained transmission among humans, thus the likelihood is low.
3. What is the risk of international spread of avian influenza A(H9N2) virus by travellers? Should infected individuals from affected areas travel internationally, their infection may be detected in another country during travel or after arrival. If this were to occur, further community level spread is considered unlikely as this virus has not acquired the ability to transmit easily among humans.
(Continue . . . )


While the risk assessments for H7N9 remains unchanged - and the virus has not demonstrated the ability to transmit efficiently from human to human -  it is fair to say that  recent developments with this virus have raised concerns world wide.

  1. This year's surge in human cases not only ends a two year decline in the number of  human infections, it is well on its way to more than doubling the size of its biggest previous epidemic (320 cases in the winter 2013-14).  
  2. H7N9 has recently split into two major lineages - Pearl River Delta and Yangtze River Delta - (see MMWR:Increase in Human Infections with Avian Influenza A(H7N9) In China's 5th Wave) This new (Yangtze River Delta) lineage will require a new vaccine - meanwhile the virus continues to evolve at an impressive rate.
  3. Previously only an LPAI virus, a new virulent (in birds) HPAI version of H7N9 emerged in Guangdong province this winter, and has demonstrated the ability to infect humans. 
  4. In a recent Eurosurveillance Research Article it was reported that despite better medical treatment for patients, the mortality rate remains high (30%+), and the authors report an`accelerated disease progression of H7N9 patients', which they note  `suggests that the viral pathogenicity might have become stronger'.
  5. The authors also noted  ` . . .  increased detection rate of H7N9 in environmental samples suggests that the virus might become more resistant to high ambient temperature.' - which you may recall was a concern raised last summer (see HK CHP: Additional Details On China's July H7N9 Cases) when we saw a dozen `out of season H7N9 cases'. 


While none of this guarantees that H7N9 will spark the next pandemic, the CDC's IRAT ( Influenza Risk Assessment Tool) ranks H7N9 as having the highest pandemic potential of 11 novel viruses currently being tracked.
And earlier this month renown virologist Dr. Guan Yi at the University of Hong Kong, in a recent interview (see NPR: A Pessimistic Guan Yi On H7N9's Evolution),  was quoted as saying  "I think this virus poses the greatest threat to humanity than any other in the past 100 years."
Add in the recent expansion of H7N9 to the north (Beijing) and west (Tibet) of China, and you have ample reasons to put H7N9 at the very top of our influenza pandemic threats list.


Friday, April 21, 2017

HK CHP Notified Of 27 New H7N9 Cases From The Mainland

Fifth Wave - FAO - April 12th



#12,400


After weeks of declining numbers following the mandated closure of many live bird markets, China's NHFPC has notified Hong Kong's CHP of 27 new H7N9 infections, the largest weekly report we've seen since the end of February. 
Seven of these cases are from Beijing, a story we've been following closely all week (see here, here, and here).
Aside from the obvious concern that H7N9 may have gotten a foothold in poultry inside one of China's largest cities (pop. 21 million) - its first major appearance in the nation's seat of power, just months before their 19th National Congress of the Communist Party of China - may have some political implications as well.

Even without Beijing's 7 cases, today's tally is the highest in a month, with hard-hit Hunan Province adding 5 more cases, and 3 each from Hebei and Sichuan. These three are the first reported from Hebei Province this year, and brings Sichuan Province - which until February of this year had never reported a case - up to 17 cases.
Somewhat surprisingly, and for the fourth week running, Guangdong Province has not reported any H7N9 cases.
As for what may account for this abrupt increase in cases, we simply don't have enough information to say. It could be as simple as - after 2 months of forced market closures - live markets in some areas may be operating again (legally, or illegally).

One week's report, however, it too small of a sample to make much of.  The next few weeks will tell us if this week's report is an aberration, or something more serious.
Today's report moves us solidly over the 620 case mark for the year (614 mainland, 5 Hong Kong, 2 Macao, 1 Taiwan), which is nearly double the largest yearly total ever recorded (2014- 320 cases).
While any revival in this year's epidemic would be concerning, we've seen no evidence of sustained or efficient transmission of the virus between humans, and the lack of recently imported cases to either Hong Kong or Macao remains reassuring.

That said, H7N9 is a continually evolving and adapting, and this year has shown subtle behavioral changes (see Eurosurveillance: Preliminary Epidemiology & Analysis Of Jiangsu's 5th H7N9 Wave), which makes it a virus we dare not ignore.

This from HK's CHP:

The Centre for Health Protection (CHP) of the Department of Health today (April 21) received notification from the National Health and Family Planning Commission that 27 additional human cases of avian influenza A(H7N9), including seven deaths, were recorded from April 14 to 20, and strongly urged the public to maintain strict personal, food and environmental hygiene both locally and during travel.
 

The 16 male and 11 female patients, aged from 34 to 79, had onset from March 22 to April 18, of whom seven were from Beijing, five from Hunan, three each from Hebei and Sichuan, two each from Shandong and Zhejiang, and one each from Anhui, Gansu, Guangxi, Jiangxi and Liaoning. Among them, 21 were known to have exposure to poultry, poultry markets or mobile stalls.

Travellers to the Mainland or other affected areas must avoid visiting wet markets, live poultry markets or farms. They should be alert to the presence of backyard poultry when visiting relatives and friends. They should also avoid purchase of live or freshly slaughtered poultry, and avoid touching poultry/birds or their droppings. They should strictly observe personal and hand hygiene when visiting any place with live poultry.

 Travellers returning from affected areas should consult a doctor promptly if symptoms develop, and inform the doctor of their travel history for prompt diagnosis and treatment of potential diseases. It is essential to tell the doctor if they have seen any live poultry during travel, which may imply possible exposure to contaminated environments. This will enable the doctor to assess the possibility of avian influenza and arrange necessary investigations and appropriate treatment in a timely manner.

While local surveillance, prevention and control measures are in place, the CHP will remain vigilant and work closely with the World Health Organization and relevant health authorities to monitor the latest developments.

The CHP's Port Health Office conducts health surveillance measures at all boundary control points. Thermal imaging systems are in place for body temperature checks on inbound travellers. Suspected cases will be immediately referred to public hospitals for follow-up.

The display of posters and broadcasting of health messages in departure and arrival halls as health education for travellers is under way. The travel industry and other stakeholders are regularly updated on the latest information.
 

The public should maintain strict personal, hand, food and environmental hygiene and take heed of the advice below while handling poultry:
 

  • Avoid touching poultry, birds, animals or their droppings;
  • When buying live chickens, do not touch them and their droppings. Do not blow at their bottoms. Wash eggs with detergent if soiled with faecal matter and cook and consume them immediately. Always wash hands thoroughly with soap and water after handling chickens and eggs;
  • Eggs should be cooked well until the white and yolk become firm. Do not eat raw eggs or dip cooked food into any sauce with raw eggs. Poultry should be cooked thoroughly. If there is pinkish juice running from the cooked poultry or the middle part of its bone is still red, the poultry should be cooked again until fully done;
  • Wash hands frequently, especially before touching the mouth, nose or eyes, before handling food or eating, and after going to the toilet, touching public installations or equipment such as escalator handrails, elevator control panels or door knobs, or when hands are dirtied by respiratory secretions after coughing or sneezing; and
  • Wear a mask if fever or respiratory symptoms develop, when going to a hospital or clinic, or while taking care of patients with fever or respiratory symptoms.

     The public may visit the CHP's pages for more information: the avian influenza page, the weekly Avian Influenza Reportglobal statistics and affected areas of avian influenza, the Facebook Page and the YouTube Channel.
Ends/Friday, April 21, 2017
Issued at HKT 17:00

Thursday, April 20, 2017

WHO H7N9 Update - April 20th

Lhasa, Tibet













#12,399


For the second time this week the WHO has published an H7N9 update, this time covering 15 cases announced by China's NHFPC on April 15th (see HK CHP Notified Of Another 14 New H7N9 Cases From The Mainland).

This report contained details of the 2nd and 3rd H7N9 cases from Tibet, which are listed as a cluster in today's report.  The first case was reported in Tuesday's WHO update.

 I've only included some excerpts, follow the link for the full report.


Disease outbreak news
20 April 2017
On 14 April 2017, the National Health and Family Planning Commission of China (NHFPC) notified WHO of 15 additional laboratory-confirmed cases of human infection with avian influenza A(H7N9) virus in mainland China.
Details of the cases

Onset dates ranged from 27 March to 11 April 2017. Of these 15 cases, three were female. The median age is 58 years old (age range among the cases is 39 to 81 years old). The cases were reported from Anhui (1), Beijing (1), Gansu (1), Henan (2), Hunan (1), Shandong (2), Sichuan (3), Tianjin (1), Tibet (2), and Zhejiang (1).

This is the first time a human case with avian influenza A(H7N9) has been reported from Gansu Province and the first time a human case with avian influenza A(H7N9) has been reported in the fifth epidemic wave in Tianjin (previously two cases were reported to WHO in July 2016).

At the time of notification, of the 11 cases with information on the condition of the case, there were two deaths, eight cases were diagnosed as having either pneumonia (1) or severe pneumonia (7), and one case was mild. Twelve cases were reported to have had exposure to poultry or live poultry market and one case had exposure to live poultry sold by street vendors or the environment near the street vendor which might have been contaminated by avian influenza A(H7N9) virus. At the time of notification, there was no information available regarding poultry exposure for two cases.


One cluster was reported and includes:
  • A 39-year-old male from Lhasa, Tibet Autonomous Region. He had symptom onset on 28 March 2017 and was admitted to hospital on 1 April 2017. He had severe pneumonia and was still in hospital until 18 April 2017. He worked at a live poultry market and was involved in the slaughter and selling of live poultry.
  • A 41-year-old male from Lhasa, Tibet Autonomous Region who was notified to WHO on 8 April 2017. He had symptom onset on 27 March 2017 and was admitted to hospital on 1 April 2017. At the time of the report he had severe pneumonia and he was still in hospital until 18 April 2017. He worked at the same live poultry stall as the 39-year-old male. He was also involved in the slaughter and selling of live poultry.

To date, a total of 1393 laboratory-confirmed human infections with avian influenza A(H7N9) virus have been reported through IHR notification since early 2013.

(SNIP)


WHO risk assessment


The number of human infections with avian influenza A(H7N9) in the fifth epidemic wave (i.e. onset since 1 October 2016) is greater than the numbers of human cases reported in earlier waves.
Human infections with the avian influenza A(H7N9) virus remain unusual. Close observation of the epidemiological situation and further characterization of the most recent human viruses are critical to assess associated risk and to adjust risk management measures in a timely manner.

Most human cases are exposed to avian influenza A(H7N9) virus through contact with infected poultry or contaminated environments, including live poultry markets. Since the virus continues to be detected in animals and environments, and live poultry vending continues, further human cases can be expected. Although small clusters of cases of human infection with avian influenza A(H7N9) virus have been reported including those involving patients in the same ward, current epidemiological and virological evidence suggests that this virus has not acquired the ability of sustained transmission among humans. Therefore the likelihood of further community level spread is considered low.