ECDC Epidemiological Update: Increased Echovirus 30 in Denmark, Germany, the Netherlands, Norway & Sweden, June to July 2018

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Earlier this week, in EID Journal: Emerging Enteroviruses In China 2010-2016, we looked at a number of Non-polio Enteroviruses (NPEV's) - including CV-A6, EV-71, and EV-D68 - which have sparked epidemics (particularly in children) around the globe.

Enteroviruses encompass a large family of small RNA viruses that include the three Polioviruses, along with myriad non-polio serotypes of Human Rhinovirus, Coxsackievirus, echovirus, and human, porcine, and simian enteroviruses.

As the chart below indicates, EV-D68 was the most reported NPEV reported in the United States between 2014-2016, but it was joined by a number of other  enteroviruses, including Echovirus 30.

Serious outbreaks tend to be cyclical, and over the past couple of years we've primarily seen EV-D68 and EV-71 reported out of Europe (see ECDC: Rapid Risk Assessment On Recent Enterovirus Outbreaks In Europe), but earlier this month the ECDC reported a jump in Echovirus 30 cases (ramping up in June) which has resulted in an increase in the number of meningitis or meningoencephalitis cases.  

Today the ECDC has published a new epidemiological update on this recent increase in Echovirus 30 infections across Northern Europe.

Epidemiological update - Increase in Echovirus 30 detections in Denmark, Germany, the Netherlands, Norway and Sweden, June to July 2018
epidemiological update

31 Aug 2018

In 2018, Norway [1] and the Netherlands [2] published reports from national public health institutes on increased Echovirus 30 (E30) detections associated with an increase in the number of meningitis or meningoencephalitis cases. Since the beginning of 2018, 407 E30 cases have been reported to ECDC in 10 EU/EEA countries based on an Epidemic Intelligence Information System–Vaccine Preventable Diseases (EPIS-VPD) data call.

Since the beginning of 2018, 407 E30 cases have been reported to ECDC in 10 EU/EEA countries based on an Epidemic Intelligence Information System–Vaccine Preventable Diseases (EPIS-VPD) data call: Austria (6), Belgium (5), Denmark (65), Germany (44), Iceland (1), Latvia (1), Netherlands (122), Norway (37), Sweden (32) and United Kingdom (England, Scotland and Wales, 94) (Figure 1).

This is an increase of 148 patients from the previous update on 3 August 2018. The figures are based on available preliminary data from 1 January to 31 July 2018. An update was also received from Croatia, Czech Republic, Finland and Slovenia, who did not detect any E30 detections in 2018. Certain typing results for enteropositive detections were still pending for July specimens in these countries.

Denmark reported that 41 out of their 65 E30 detections (63%) were from cerebrospinal fluid (CSF) specimens, which can be used as a proxy for severe infection. Germany collected specimens only from aseptic meningitis, encephalitis or acute flaccid paralysis cases, therefore their 44 E30 patients all had central nervous system (CNS) symptoms.

A total of 94 out of 132 patients (71%) were reported with central nervous system symptoms from the Netherlands, Norway and the United Kingdom. For 68 patients, further symptom categories were reported and classified as meningitis (n=36, 53%), meningoencephalitis (n=26, 38%) or other CNS symptoms (n=5, 7%; one additional patient reported with sepsis, fever, tachycardia and groaning respiration).

For the other patients, the specific symptoms were unknown. Up until now, age information was available for 361 of the patients and the epidemic has mostly affected individuals under 3 months (n=86, 24%) and 26–45 years of age (n=145, 40%). Based on available preliminary data, the male (n=208) to female (n=148) ratio was 1.4.

E30 is a non-polio enterovirus that causes aseptic meningitis outbreaks worldwide. Such outbreaks have been detected earlier in Europe [3–10] and occur usually at five- to six-year intervals [11]. The exact transmission route of current infections is unknown. However, non-polio enteroviruses usually transmit through faecal-oral or oral-oral routes.

Unfortunately, specific prevention or control measures are not available for E30 and symptomatic treatment should be applied. Good hygienic practices such as frequent hand washing, avoidance of shared utensils, bottles or glasses and disinfection of contaminated surfaces (e.g. with diluted bleach solution) are recommended to prevent the spread of E30 from person to person.

In affected countries, further transmission of E30 cannot be excluded and all EU/EEA Member States should remain vigilant for the continuing E30 epidemic. Where relevant, national public health authorities should consider informing clinicians of increased numbers of aseptic meningitis cases related to E30 infections and the importance of collecting respiratory, stool and CSF specimens even if white blood cell count is normal, as well as adhering to recommendations on detection of non-polio enteroviruses in laboratories [12].
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EID Journal: Introduction of Eurasian-Origin Influenza A(H8N4) Virus into North America by Migratory Birds

Credit USGS

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Four short years ago there was still a bitter debate over whether migratory birds were A) capable of spreading HPAI viruses over long distances and B) whether migratory birds could bring Eurasian avian flu viruses to North America by crossing the Bering straits.

While it was known that some waterfowl species could carry HPAI viruses asymptomatically, the rallying cry that `Sick birds don’t fly’ was often used to argue that migratory birds couldn't be to blame for the international spread of the virus (see India: The H5N1 & Migratory Birds Debate).

In January of 2014, in response to the South Korean assertion that migratory Birds were the likely source of their H5N8 outbreak, the UN's Scientific Task Force on Avian Influenza and Wild Birds quickly issued a statement saying:

"There is currently no evidence that wild birds are the source of this virus and they should be considered victims not vectors."

A year later they would modify their stance somewhat, by saying that typically the `. . . spread of HPAI virus is via contaminated poultry, poultry products and inanimate objects although wild birds may also play a role'.

The great leap of HPAI H5N8 from Asia to North America in late 2014, and its spread to Europe, the Middle East, and Africa in 2016-17, have pretty much cemented the role of migratory birds in spreading HPAI viruses across long distances (see Migratory Birds & The Spread Of Highly Pathogenic Avian Flu).

In fairness, recent genetic changes in clade 2.3.4.4. HPAI H5 viruses appear to make them more suitable for carriage by wild and migratory birds, although earlier HPAI H5N1 clades managed to mount impressive global geographical gains as far back as  2005-2006.

Less settled continues to be how likely it is that Eurasian avian viruses can cross the Bering Straits and establish themselves in North American birds, although the arrival of HPAI H5N8 to the Pacific Northwest in late 2014 and the resultant record-setting epizootic showed that it was possible.

Alaska is not only the closest American soil to Asia, but is also a major summer roosting spot for hundreds of migratory bird species, making it an ideal spot for surveillance and research. Some we've looked at over the years include:

USGS: Alaska Still A Likely Portal For Introduction Of Avian Viruses

EID Journal: Reassortment in Wild Birds in Alaska before H5 Clade 2.3.4.4 Outbreaks

USGS: Alaska - A Hotspot For Eurasian Avian Flu Introductions Where The Wild Duck Goes

USGS: Genetic Evidence Of The Movement Of Avian Influenza Viruses From Asia To North America

As the map at the top of this blogs shows, the Pacific Americas Flyway meets up with both the Central Pacific and (more importantly) the Asian-Australian Flyways over Alaska and Siberia. 

Primarily north-south migratory routes, these flyways all overlap, and therefore allow for lateral (east-west) movement of birds as well.

With Asia a hotbed of avian flu reassortment - spawning H5N1, H5N2, H5N6, H5N8, H7N9, H9N2, H10N8, and others in recent years - the possibility that these viruses might hitch a ride on a migratory birds and turn up in North America is of considerable concern. 

All of which brings us to a new EID Journal Research Letter, that announces the detection of another Eurasian (LPAI H8N4) virus - the 4th such detection in 7 years - among migratory birds in Alaska, and suggests that international spread may not be as rare as previously thought.

I've only excerpted a few selections from a much longer report, so follow the link to read it its entirety. 

Volume 24, Number 10—October 2018

Research Letter

Introduction of Eurasian-Origin Influenza A(H8N4) Virus into North America by Migratory Birds

Andrew M. Ramey , Andrew B. Reeves, Tyrone Donnelly, Rebecca L. Poulson, and David E. Stallknecht

Author affiliations: US Geological Survey Alaska Science Center, Anchorage, Alaska, USA (A.M. Ramey, A.B. Reeves, T. Donnelly); University of Georgia, Athens, Georgia, USA (R.L. Poulson, D.E. Stallknecht)

Suggested citation for this article

Abstract

We identified a Eurasian-origin influenza A(H8N4) virus in North America by sampling wild birds in western Alaska, USA. Evidence for repeated introductions of influenza A viruses into North America by migratory birds suggests that intercontinental dispersal might not be exceedingly rare and that our understanding of viral establishment is incomplete.

        (SNIP)

During 2010–2016, research and surveillance for influenza A viruses in wild birds inhabiting North America have provided evidence for the intercontinental dispersal of the following 4 viral genome constellations between Eurasia and North America: H16N3 (9), H9N2 (3), highly pathogenic clade 2.3.4.4 H5N8 (10), and H8N4 (this study).

Four reports of independent purported intercontinental dispersal events for influenza A viruses via migratory birds during 7 years of sampling do not disprove the paradigm of restricted viral dispersal between Eurasia and North America. However, repeated detections of these viruses crossing the Bering Strait (3,10; this study) suggest that viral dispersal between East Asia and North America might not be exceedingly rare.

Thus, a lack of selective advantage for comparatively rare foreign-origin influenza A viruses, purifying selection for endemic viruses, or both might be important mechanisms regulating the establishment of these viruses within the wild bird reservoir.

Therefore, additional research directed toward understanding selection pressures regulating the establishment of these viruses might provide useful inference for informing surveillance and response activities for economically costly or potentially pandemic foreign-origin viruses in wild birds inhabiting North America.

Dr. Ramey is a research scientist at the US Geological Survey Alaska Science Center, Anchorage, Alaska. His primary research interests include the maintenance and dispersal of infectious agents by wildlife.

While there is nothing particularly ominous about an LPAI H8N4 virus, its genetic components - which can be shared via reassortment - can help drive increased diversity of local viruses. The discovery of an almost exact copy of the Asian strain in Alaska is also further proof that migratory birds can bring in Eurasian avian flu viruses.

All of this matters because our own Arctic Refuge, where more than 200 bird species spend their summers, serves as a central hub, and funnels migratory birds south each fall via all four North American Flyways.

Credit U.S. Fish & Wildlife

With migratory birds soon to head south from their summer roosting areas, the risk of seeing new reassortants (LPAI or HPAI) emerge along these migratory routes will increase.

Between 2016 and 2017 we saw three novel reassortants, all of which are now on the CDC's IRAT list.

H7N8 [A/turkey/Indiana/1573-2/2016]
H7N9 [A/chicken/Tennessee/17-007431-3/2017]
H7N9 [A/ chicken/Tennessee /17-007147-2/2017]

Although HPAI reassortant viruses have historically posed a much bigger threat to Asia and Europe, the experience of 2014-15 shows that North America is not immune, and so poultry interests along the flyways will want to ramp up their biosecurity as fall approaches.

China MOA: 5th Province (Anhui) Reports Outbreak Of African Swine Fever (ASF)

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For the fifth time in less than a month China's MOA has announced a new outbreak of African Swine Fever (ASF), involving yet another province (Anhui).  This comes just 24 hours after China's MOA warned that additional outbreaks were possible (more on that after today's announcement).

First the (translated) announcement from the MOA:

An African swine fever epidemic occurred in Nanling County, Wuhu City, Anhui Province

Date: 2018-08-30 20:23 Author: Source: Ministry of Agriculture and Rural Press Office

The news office of the Ministry of Agriculture and Rural Affairs was released on August 30, and a pig swine epidemic occurred in Nanling County, Wuhu City, Anhui Province.

On August 29, the Anhui Provincial Animal Husbandry and Veterinary Department discovered that pigs from a farm in Nanling County, Wuhu City died of unknown causes during the investigation of the African swine fever epidemic. On August 30th, it was diagnosed as an African swine fever epidemic by the China Center for Animal Health and Epidemiology (National Center for Animal Diseases Research). The field coexisted 459 pigs, and as of now, there are 185 cases and 80 deaths.

After the outbreak, the Ministry of Agriculture and Rural Affairs immediately dispatched a steering group to Anhui Province. The local authorities have started the emergency response mechanism according to the requirements, and adopted measures such as blockade, culling, harmless treatment, disinfection, etc., and have culled 379 hair sick pigs and the same group of pigs. All the sick and culled pigs have been harmlessly treated. . At the same time, all live pigs and susceptible animals and products are prohibited from entering or leaving the blockade. At present, the epidemic has been effectively disposed of.

Yesterday China's MOA released a long Q&A on ASF on their website, where they announced the Ministry would `Go All Out' to control the epidemic, but cautioned that additional outbreaks were possible.

Below you'll find a (translated) excerpt.

Go all out to African swine fever epidemic prevention and control

The Ministry of Agriculture and Rural Animal Husbandry and Veterinary Bureau answered reporters' questions on African swine fever epidemic

Date: 2018-08-29 10:57 Author: Source: Agriculture and Rural Department of Public Information Office

Since August this year, China 4 cases of African swine fever outbreak has occurred, the Ministry of Agriculture and Rural Animal Husbandry and Veterinary Bureau to answer questions from reporters on issues related to African swine fever epidemic prevention and control.

　　Q: Can you tell us about the current situation of African swine fever epidemic prevention and control?

　　A: Since August this year, Shenbei Shenyang, Zhengzhou Economic Development Zone, Lianyungang, Jiangsu Haizhou District, Yueqing City, Wenzhou, Zhejiang has four cases of African swine fever outbreak, which was first introduced into China African swine fever. After the outbreak, the Ministry of Agriculture and Rural start Ⅱ level emergency response according to "African swine fever epidemic contingency plan", the first time to the public the epidemic situation and early warning information, make every effort to epidemic prevention and control.

• First, quickly and decisively disposal epidemic. Local guide immediately launched the emergency response, taking blockade, culling, harmless treatment, disinfection and other measures, also asked to strengthen supervision over the movement of live pigs, pause pig out high-risk areas, strengthening biosafety management.
• Second, the depth retrospective epidemic. Provincial Department set up a joint working group, in close cooperation with public security organs, carry out a comprehensive epidemiological investigation.
• Third, the full deployment of prevention and control. Has issued a notification, video conferencing, comprehensive arrangements for national African swine fever prevention and control work. At the same time, convene an expert committee judged the epidemic situation.
• 4 is a comprehensive arrangements for monitoring the investigation. Carry out a comprehensive investigation and guidance around monitoring to ensure that farming, trading, slaughtering link full coverage of key areas and key links to sample monitoring full coverage, pig farms in high-risk areas sample monitoring coverage. Up to now, the country has a total field investigation point 16,348,300 times, pig 721,494,600 times; sample collection has accumulated 16970 copies, 16965 copies inspection.
• 5 is to strengthen scientific propaganda. In a timely manner to the public, outbreak information to the authorities and international organizations to promote African swine fever scientific knowledge through a variety of channels, the elimination of public panic.
• 6 is to strengthen coordination among various departments. General Administration of Customs released the first time the warning notification, departments will convene Chamber of Commerce, a clear division of labor, detailed measures to further the formation of a joint prevention and control of the force.

Currently 4 outbreaks have been effectively disposed of. But the present situation, the virus contaminated surfaces to be further investigation of the epidemic, there are many uncertainties subsequent epidemic situation, do not rule out continued to appear may contain new outbreaks. In addition, the disease in neighboring countries, long-term me popular, constantly spreading, passing again the risk is still great.

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While ASF does not infect humans it has the potential to cause great harm to China's pork industry, and by extension to China's economy, food supply, and potentially its political stability.  

Over the past week we've looked at a number of analyses of ASF in China - and in Europe - including:

DEFRA: Update On African Swine Fever (ASF) In Eastern EU

FAO: African swine fever (ASF) threatens to spread from China to other Asian countries

EID Journal: Molecular Evolution, Diversity, and Adaptation of Influenza A(H7N9) Viruses in China

Although only first reported in China less than a month ago, 5 outbreaks of ASF in 5 different provinces in just under 4 weeks raises questions about how this virus is spreading so quickly, and long this virus may have been circulating unnoticed in China. 

Stay tuned. 

EID Journal: Emerging Enteroviruses In China 2010-2016

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Non-polio Enteroviruses (NPEV's) - of which there are literally scores - typically spread in the summer and early fall, and generally produce mild or even asymptomatic infections, mostly in children under the age of 10. 

Symptomatic cases can range from just a mild fever or a runny nose - to Hand Foot Mouth Disease (HFMD), a generally mild childhood disease characterized by blisters on the hand, feet, and mouth - to (in rare cases) a polio-like paralysis and sometimes even death. 
 
For several decades - particularly in Asian and Western Pacific nations - we've monitored yearly NPEV epidemics, with the most severe illness linked to Human Enterovirus 71 (EV-71).

• In 2009 China reported 1,155,525 HFMD cases, including 13,810 severe cases and 353 deaths. Among laboratory confirmed cases, EV71 was responsible for 41% of cases, 82% of severe cases, and 93% of the deaths (cite WHO HFMD Guide Pg.6).
• In 2012, we saw an outbreak of EV-71 in Cambodia that claimed the lives of dozens of children (see Updating The Cambodian EV71 Story).
• In 2013 in Australia: Acute Flaccid Paralysis & EV71, we looked at a report that described 5 cases of acute flaccid paralysis (AFP) in children who tested positive for the EV71 virus.

Less well known, but rapidly coming up in the ranks, is Coxsackievirus A6  (CV-A6) which was only first described about a decade ago. In 2009, the CDC’s EID Journal carried a dispatch regarding an outbreak of HFMD in Finland due to an unusual, and apparently emerging, viral cause; the CV-A6.

Since then, we’ve seen a growing number of reports of HFMD outbreaks around the world attributed to this emerging coxsackievirus, including outbreaks in Europe, Asia and North America (see Nevada: HFMD Coxsackievirus A6 Outbreak).

Earlier this year we looked at a Virology journal report that indicated CVA6 has overtaken both EV71 and CV-A16 as the primary cause of HFMD in China, and that it continues to evolve.

Today we've a new report in the EID Journal, that confirms that CV-A6 has emerged as a substantial driver of severe enterovirus infection in China since 2010.

Dispatch

Emerging Enteroviruses Causing Hand, Foot and Mouth Disease, China, 2010–2016

Yu Li1, Zhaorui Chang1, Peng Wu1, Qiaohong Liao, Fengfeng Liu, Yaming Zheng, Li Luo, Yonghong Zhou, Qi Chen, Shuanbao Yu, Chun Guo, Zhenhua Chen, Lu Long, Shanlu Zhao, Bingyi Yang, Hongjie Yu2, and Benjamin J. Cowling

Abstract

Coxsackievirus A6 emerged as one of the predominant causative agents of hand, foot and mouth disease epidemics in many provinces of China in 2013 and 2015. This virus strain accounted for 25.9% of mild and 15.2% of severe cases in 2013 and 25.8% of mild and 16.9% of severe cases in 2015.

Hand, foot and mouth disease (HFMD) is a common childhood infectious disease caused by enteroviruses (1). In China, HFMD cases must be reported to the Notifiable Infectious Diseases Reporting Information System. Apart from clinical and demographic information, case notifications also include etiologic results, if available, classified into 3 categories: enterovirus A71 (EV-A71), coxsackievirus (CV) A16, and other enteroviruses.

However, not all cases have etiologic results, the Notifiable Infectious Diseases Reporting Information System (NIDRIS) does not indicate cases that tested negative for enteroviruses, and testing methods vary among hospitals (2). To capture more information on the etiologic spectrum of HFMD in China, a laboratory surveillance network has been established in provincial-level centers for disease control and prevention (CDCs).

EV-A71 and CV-A16 were previously believed to be the main causative viruses for HFMD in Asia, but several studies have suggested that other enteroviruses appear to be increasing since 2008 (3–9).

Nevertheless, these past studies in China could not provide an overview at the national level because of limitations in geographic locations or study settings; furthermore, none of them systematically examined proportions of specific enteroviruses testing positive among tested HFMD cases. We analyzed data from this laboratory network to examine causative pathogens of HFMD cases and epidemiologic differences associated with various pathogens.

(SNIP)

Conclusion

Data from national laboratory network surveillance of HFMD in China show that detection of enteroviruses other than EV-71 and CV-A16 has been increasing in both mild and severe cases and that CV-A6 has been emerging as another predominant serotype recently, but not in every province.

Serotyping of individual enteroviruses apart from currently tested EV-71 and CV-A16 is suggested for routine virologic surveillance. Further studies may be needed to investigate potential cross immunity between EV-A71 and other enteroviruses such as CV-A6, CV-A10, and others.

Dr. Li is a doctoral candidate at School of Public Health, The University of Hong Kong. His primary research interests include epidemiology and transmission dynamics of zoonotic and vectorborne diseases, and hand, foot and mouth disease.

Although outbreaks of CV-A6 in the United States have been limited, in 2012, in EID Journal: HFMD Cluster Due To CVA6 we looked at a report on cluster of 8 patients who were treated CVA6 HFMD at Boston Children’s Hospital.

The authors cautioned:

Given the numerous CVA6 outbreaks in multiple countries in 2008 and a US population that may be relatively naïve to this serotype, CVA6 is likely to spread throughout North America.

In 2014 a North American outbreak of another emerging enterovirus - EV-D68 - was linked to a concurrent spike in AFP (Acute Flaccid Paralysis) cases across the United States, and since then we've seen a number of EV-D68 outbreaks around the world (see here, here & here).

While a causal link between EV-D68 and AFM hasn't been fully established, last January's Eurosurveillance Review: Association Between Acute Flaccid Myelitis (AFM) & Enterovirus D68 (EV-D68), presented a pretty good argument for causation.

Just as with influenza, these non-polio enteroviruses continue to evolve - and while not as deadly as flu - they are fully capable of causing large epidemics. 
 
Some of my earlier blogs NPEVs include:

MMWR: Cluster of Acute Flaccid Myelitis in Five Pediatric Patients - Arizona, 2016

CDC Acute Flaccid Myelitis Update - January 2017

EID Journal Upsurge In EV-D68 In The Netherlands, 2016

ECDC: Rapid Risk Assessment On Recent Enterovirus Outbreaks In Europe

EID Journal: New Introductions Of EV-71 Subtype C4 To France – 2012

 

DEFRA: Update On African Swine Fever (ASF) In Eastern EU

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While the arrival of African Swine Fever to China earlier this month - followed by 3 more outbreaks - has been the big ASF story of late, the virus continues to spread widely through Eastern Europe as well.

Yesterday the OIE reported 23 new outbreaks (since Aug 2nd) in Romania, which will require the culling of more than 170,000 pigs.  

Three of those outbreaks occurred on the 2nd largest pig farm in Europe, located in Tufesti, Braila.

While the OIE lists the source of this outbreak as `unknown or inconclusive', a report appearing two days ago in Pig's Progress (ASF on Romania’s largest pig farm: 140,000 pigs culled) suggests some smallholders in the region may  have been dumping dead pigs into the river, and the virus has infected downstream farms drawing water from the Danube.

Whatever the cause, since it first arrived from Africa in 2007, ASF has been spreading inexorably across Eastern Europe and Russia, often aided and abetted by poor farm biosecurity and sometimes by the illegal sale and transport of swine or pork products. 

While Western Europe remains unscathed by these outbreaks, they remain wary, knowing how easily the virus could be imported in their direction. 

The UK's DEFRA has released a new update (written before the latest Romania Outbreak), which details ASF's geographic expansion, including some recent yet-to-be-explained large leaps in Romania and a trend towards larger commercial farms being struck in places like Russia, Latvia, Lithuania, Poland and Ukraine.

Much like we saw in Sunday's report (see South Korea Detects ASF Gene In Chinese Food Products: Additional Testing Underway), the authors warn of the dangers of travelers returning from ASF endemic areas carrying contaminated food items. 

I've only included some excerpts from a larger report, so follow the link to read it in its entirety.

Updated Outbreak Assessment #16
African Swine fever in Eastern Europe
23 August 2018
Ref: VITT/1200 ASF in Eastern Europe

Disease report

Since our last update on 25 th June 2018, cases of African Swine Fever (ASF) have continued to be reported in wild boar and outbreaks in domestic pigs in Eastern Europe and western Eurasia (see map). While ASF has not moved substantially westward across Europe since the reports in wild boar in the Czech Republic in June 2017, outbreaks in backyard pigs in Romania have increased exponentially and the disease has recently jumped west within Romania, likely from the south-east part of the country near the border with Ukraine and there are now 9 regions reporting outbreaks in backyard domestic pigs (Bihor, Braila, Calarasi, Constanta, Galati, Ialomita, Ilfov, Satu Mare and Tulcea). 

In addition outbreaks have occurred in pig farms in northern Poland along the border with Kaliningrad. During July and August, ASF outbreaks have been reported in some large pig farms (>1,000 pigs) particularly in the northern parts of Eastern Europe (non-EU and EU).

Table. Numbers of outbreaks in domestic pigs (i.e. backyard and commercial) in July andAugust 2018

        (SNIP)

Situation assessment
 
ASF is continuing to spread within Eastern Europe, although there is no evidence of spread westwards in the EU. There are two trends observed which are cause for concern. 

First is the spread and number of outbreaks in the large non-commercial backyard pig sector in Romania; the latest reports indicate a large jump into Ilfov county some 200 km west of Tulcea county where the number of cases in non-commercial backyard pigs has increased exponentially. Understanding how disease is spreading so rapidly in the backyard sector in the area is vital to designing effective control measures. 

The second is the increase in outbreaks in large commercial pig farms (>1,000 pigs) in countries including Russia, Latvia, Lithuania, Poland and Ukraine. An outbreak of ASF has also been reported in late July for the first time in a large pig farm (>1,000 pigs) along the northern border of Poland near the Russian exclave of Kaliningrad, therefore controls on the commercial production of pork products will rely heavily on effective ante and post mortem inspections.

Some 95,000 kg of total pork meat has been legally imported to the UK in 2018 to date from Romania and a similar amount from Poland (HMRC Trade Stats). Commercially produced meat from the ASF-affected regions cannot be traded as fresh or frozen meat to other member states.

However there are concerns around ASF-contaminated or infected pork products from non-EU countries entering the EU in passenger luggage and then being discarded in areas where wild boar or outdoor pigs are present. Publicity campaigns are in place to discourage EU nationals from bringing pork products into UK, but keepers should also be aware of this high risk activity.

Conclusion

The risk of ASF introduction to the UK was previously raised to “low” in August 2017. This was because despite the relatively low level of legal trade in live pigs or commercially produced pig products, there could be a risk from the fomite pathway involving movement of people and vehicles from affected Eastern EU countries and the evidence around the findings of contaminated / infected non-EU origin pig products detected in the EU (according to presentations by Hungary and Slovakia at PAFF this year).

This risk is showing no sign of decreasing, and it is vital that visitors to the EU Member States understand the impact of bringing personal food items which are discarded for wildlife to pick up. Similarly, visitors to affected areas that have any contact with the environment around wild boar cases should be vigilant about cleaning and disinfecting any vehicles, clothing, footwear or equipment, including hunting equipment, which may be contaminated. Hunters visiting affected areas should not bring back “trophies” as these could be contaminated.

The current risk of ASF introduction to the UK is therefore still considered to be “low”, although the situation is being kept under review.

We would like to highlight to all pig keepers and the public to ensure pigs are not fed catering waste, kitchen scraps or pork products, thereby observing the swill feeding ban.

All pig keepers should be aware that visitors to their premises should not have had recent contact with affected regions. Anybody returning from the affected EU MSs should avoid contact with domestic pigs, whether commercial holdings or smallholdings, areas with feral pigs or wild boar, until they are confident they have no contaminated clothing, footwear or equipment. Pig keepers and veterinarians should remind themselves of the clinical signs for ASF, which may not always be immediately obvious, as this virus appears to have reduced pathogenicity according to some disease reports. Any suspect cases must be reported promptly.

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FAO: African swine fever (ASF) threatens to spread from China to other Asian countries

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Sunday's report (see South Korea Detects ASF Gene In Chinese Food Products: Additional Testing Underway) highlights how easily African Swine Fever could spread from China - where it was only first reported just over 3 weeks ago - to neighboring countries.

While not able to infect humans, ASF is highly lethal and contagious in swine, and has been steadily making its way across Eastern Europe and Russia since it arrived in Georgia in 2007.

For a country like China, the biggest pork raising and consuming country in the world - with hundred of millions of people to feed - its spread could prove devastating.

As we've discussed often in this blog, food insecurity - whether due to disease, floods, droughts, or other causes - can pose both severe economic and societal challenges (see Iran: Bird Flu, Food Insecurity & Civil Unrest).

A national security threat the central Chinese government is keen to avoid.

The FAO's report The State of Food Security and Nutrition in the World 2017 shows a sharp rise in food insecurity around the world since 2014 (see chart below), and warns:

 

AFTER A PROLONGED DECLINE, WORLD  HUNGER APPEARS TO BE ON THE RISE AGAIN

Today the FAO has a fresh warning, and is calling for regional collaboration, to try to help stave off the greater spread of ASF across China and the rest of Asia.

Outbreak of African swine fever threatens to spread from China to other Asian countries 

FAO urges regional collaboration including stronger monitoring and preparedness measures

There is no effective vaccine to protect swine from the disease.

28 August 2018, Rome/Bangkok - The rapid onset of African Swine Fever (ASF) in China, and its detection in areas more than one thousand kilometres apart within the country, could mean the deadly pig virus may spread to other Asian countries anytime, the UN's Food and Agriculture Organization (FAO) warned today.

There is no effective vaccine to protect swine from the disease. And, while the disease poses no direct threat to human health, outbreaks can be devastating with the most virulent forms lethal in 100 percent of infected animals.

So far, in efforts to control the spread of the disease, Chinese authorities have culled more than 24,000 pigs in four provinces. China is a major pig producing country and accounts for approximately half the global population of swine, estimated at 500 million. Its value chain involves a very large and wide range of producers from small family holdings to large-scale commercial operators.

While this is not the first time African Swine Fever has been detected outside of Africa - outbreaks in Europe and the Americas date back to the 1960s - its detection and diverse geographical spread of the outbreaks in China have raised fears that the disease will move across borders to neighbouring countries of Southeast Asia or the Korean Peninsula where trade and consumption of pork products is also high.

A robust virus with a long life

The ASF virus is very hardy and can survive long periods in very cold and very hot weather, and even in dried or cured pork products. The strain detected in China is similar to one that infected pigs in eastern Russia in 2017 but, so far, and while the investigations continue, the China Animal Health and Epidemiology Center has found no conclusive evidence of this latest outbreak's source or linkages.

"The movement of pig products can spread diseases quickly and, as in this case of African Swine Fever, it's likely that the movement of such products, rather than live pigs, has caused the spread of the virus to other parts of China," explained Juan Lubroth, FAO's Chief Veterinarian.

FAO's Emergency Centre for Transboundary Animal Diseases (ECTAD) is communicating closely with authorities in China to monitor the situation and to respond effectively to the outbreak inside the country, as well as with authorities in neighbouring countries, to raise the importance of preparedness to respond to the threat of further spread.

(Continue . . . )

It would be bad enough if African Swine Fever and Avian flu were the only threats to agricultural production in China, but to these you can add:

Anthrax,  Foot & Mouth Disease (FMD), a bevy of porcine viruses (including Porcine Reproductive and Respiratory Syndrome (PRRS), Porcine epidemic diarrhea (PED) & porcine enteric alphacoronavirus [PEAV]), and an increasingly erratic global climate spawning floods, droughts, and heat waves.

To put it gently, the challenges of the 21st century continue to mount.

EID Journal: Molecular Evolution, Diversity, and Adaptation of Influenza A(H7N9) Viruses in China

Credit FAO

#13,467


While H7N9 activity in China has been greatly suppressed these past 12 months (see chart above) - likely due to an aggressive national poultry vaccination campaign - the virus continues to circulate and evolve in poultry, and its pandemic threat has not gone away.

The CDC's IRAT (Influenza Risk Assessment Tool) Rankings, places two separate LPAI H7N9 strains at the very top of their list of novel viruses with pandemic potential, and the WHO continues to refine their Candidate Vaccines For Pandemic Preparedness.

The runaway outbreak of 2016-2017, which saw nearly as many human infections as had been reported in the previous four outbreaks combined, was notable for not only its size, but for its geographic expansion across China and the emergence of new strains and lineages of the virus.

During this 5th wave, a new HPAI (highly pathogenic) H7N9 virus emerged in Guangdong province, and quickly began to spread to other provinces. 

Although case reports are limited, some early evidence has suggested this HPAI version might pose an even greater threat to human health than its LPAI cousin (see Eurosurveillance: Epidemiology of Human HPAI H7N9 Infection - Guangdong Province).

This recent increase in viral diversity is one of the reasons why there is so much concern over the refusal of China to share virus samples with the United States (see New York Times China Has Withheld Samples of a Dangerous Flu Virus).

Chinese researchers do, however, continue to publish information on H7N9 (and other) avian flu viruses - and while no substitute for the CDC having access to the actual virus - it does provide us with some valuable data.

Yesterday, the CDC's EID Journal published a new study which has found even more diversity among 5th wave H7N9 viruses than was previously known, and presents evidence of a high rate of adaptive molecular evolution.

This is a long, detailed study, and so I've only excerpted some highlights (bolding mine). Follow the link to read it in its entirety. When you return, I'll have a bit more.

Volume 24, Number 10—October 2018
Research

Molecular Evolution, Diversity, and Adaptation of Influenza A(H7N9) Viruses in China
 
Jing Lu1 , Jayna Raghwani1, Rhys Pryce, Thomas A. Bowden, Julien Thézé, Shanqian Huang, Yingchao Song, Lirong Zou, Lijun Liang, Ru Bai, Yi Jing, Pingping Zhou, Min Kang, Lina Yi, Jie Wu2, Oliver G. Pybus2, and Changwen Ke2
Author affiliations: Guangdong Provincial Center for Disease Control and Prevention, Guangzhou, China (J. Lu, Y. Song, L. Zou, L. Liang, R. Bai, Y. Jing, P. Zhou, M. Kang, L. Yi, J. Wu, C. Ke); Guangdong Provincial Institution of Public Health, Guangzhou (J. Lu, P. Zhou, L. Yi); University of Oxford, Oxford, UK (J. Raghwani, R. Pryce, T.A. Bowden, J. Thézé, O.G. Pybus); Beijing Normal University, Beijing, China (S. Huang)

Abstract

The substantial increase in prevalence and emergence of antigenically divergent or highly pathogenic influenza A(H7N9) viruses during 2016–17 raises concerns about the epizootic potential of these viruses.

We investigated the evolution and adaptation of H7N9 viruses by analyzing available data and newly generated virus sequences isolated in Guangdong Province, China, during 2015–2017. Phylogenetic analyses showed that circulating H7N9 viruses belong to distinct lineages with differing spatial distributions.

Hemagglutination inhibition assays performed on serum samples from patients infected with these viruses identified 3 antigenic clusters for 16 strains of different virus lineages. We used ancestral sequence reconstruction to identify parallel amino acid changes on multiple separate lineages. We inferred that mutations in hemagglutinin occur primarily at sites involved in receptor recognition or antigenicity.

Our results indicate that highly pathogenic strains likely emerged from viruses circulating in eastern Guangdong Province during March 2016 and are associated with a high rate of adaptive molecular evolution.

        (SNIP)

Discussion

Our results show that H7N9 viruses of lineage C, which were prevalent in the recent fifth influenza epidemic wave in China, comprise 2 geographically distinct clades (C1 and C2) that have undergone adaptive evolution.

Clade C1 is found primarily in eastern and central China and clade 2 in Guangdong Province, and both clades appear to have circulated in bird populations for ≈3 years. Our ancestral state reconstruction analysis provides crucial evidence that 2 successful lineages of H7N9 viruses (lineages B and C) have experienced multiple parallel amino acid changes (Figures 4, 5), suggesting the possible action of convergent molecular evolution.

We also observed a higher rate of virus adaptation in the eastern Guangdong Province (C2 clade compared with C1). Although clades C1 and C2 are phylogenetically closely related, serum from a clade C1 virus-infected patient has moderate reactivity with C2 strains from 2015–2016 and poor reactivity to the HP virus from 2016–2017.

The higher adaptation rate and antigenic changes in clade C2 are of concern from a public health perspective. Introduction of HP avian influenza into domestic poultry might constitute a serious risk, as demonstrated by emergence of goose–Guangdong lineage HP H5N1 viruses, which spilled back into wild birds and caused the longest global outbreak of HP avian influenza to date (33).

        (SNIP)

Recent studies have shown that the HP H7N9 virus is more pathogenic in mice, and more thermally stable, than low pathogenicity A/Anhui/1/2013 virus (47,48). Current surveillance indicates that HP H7N9 viruses have spread to several provinces in China and are responsible for large influenza outbreaks in poultry in central and northern China, that show high mortality rates (http://www.fao.org/ag/againfo/programmes/en/empres/H7N9/situation_update.html).

This finding raises the possibility of global dissemination of H7N9 viruses through migration of wild birds, in a manner similar to that observed for HP H5N1 viruses first identified in Guangdong Province (32). Although vaccination of poultry against H7N9 virus has been now implemented in some regions of China, virus adaptation and spatial distribution should be more closely monitored.

Dr. Lu is a virologist at the Guangdong Provincial Center for Disease Control and Prevention, Guangzhou, China. His primary research interests are epidemiology, evolution, and transmission of viruses associated with emerging infectious diseases.

While China's massive poultry vaccination campaign over the summer of 2017 appears to have been a huge success, the rapid molecular evolution of the H7N9 virus could allow new, antigenically different strains, to evade its effects.

Over its first 5 years, H7N9 has been a primarily a Mainland China poultry problem, and we've seen relatively little information on it in wild birds.

But its recent morphing into a more heat tolerant HPAI version could make it better adapted to wild and migratory birds, which might lead to its regional or even global spread, such as we've seen previously with HPAI H5N1 and HPAI H5N8/H5N6.

Although the year-long respite in H7N9 outbreaks and human infections has been a welcome development, today's report is a reminder that that status is unlikely to last forever.

But whether it is H5 or H7, or some other novel flu, another pandemic is pretty much guaranteed. The only real questions are how soon? How bad? And how ready will we be when it comes. 

UK: PHE Advice To Travelers Returning From The Middle East

Credit ECDC

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While the the total number of MERS-CoV cases exported from the Middle East since 2012 has remained small, their impact - such as we saw in South Korea during the summer of 2015 - can be tremendous (see Study: Burnout & PTSD Among Nurses Working During A Large MERS-CoV Outbreak - Korea, 2015).

Last week's report of an imported case in England (see UK PHE: Imported MERS Case In England (Leeds)) is reminder that - with an incubation period of up to 15 days - a MERS infected individual can often have a sizable window in which to travel before symptoms appear.

With the Hajj just ended, over the next couple of weeks hundreds of thousands of religious pilgrims will be leaving Saudi Arabia and flying to back to their home countries around the globe.

And if past years are any gauge, many will return home with mild respiratory infections. A 2012 study in Clinical Infectious Diseases (co-authored by Ziad Memish) - called Unmasking Masks in Makkah: Preventing Influenza at Hajj – found:

Each year more than 2 million people from all over the world attend the Hajj pilgrimage to Saudi Arabia. At least 60% of them develop respiratory symptoms there or during outward or homebound transit [1, 2]

Since the initial signs of MERS infection are often similar to a cold or the flu, differentiating who is - and who isn't - infected can be a extremely difficult, even for doctors used to seeing cases (see Evaluation of a Visual Triage for the Screening of MERS-CoV Patients).

All of which means that airport screeners and thermal cameras have little hope in preventing entry of MERS infected travelers  (see Why Airport Screening Can’t Stop MERS, Ebola or Avian Flu).

Which has prompted many countries - including England - to advise travelers returning from the Middle East to be aware of changes in their health in the two weeks following their return, and to report any fevers, coughs, or respiratory illness to their doctor immediately. 

PHE Twitter Feed

The PHE blog Public Health Matters has more information in Middle East Respiratory Syndrome (MERS): Who is at risk?

Despite our annual concerns, we've never seen a major outbreak of MERS linked to religious pilgrims returning from the Hajj. Whether this has been a matter or luck, or is due to limitations in how well MERS circulates in the community, remains an open question. 

That said, three years ago we watched the tragic results of a single MERS  infected business traveler returning from the Middle East to South Korea.

Sparked by a just one case, MERS spread like wildfire due to a handful of `super spreaders', whose impact was magnified by overcrowded hospital Emergency Rooms and hospital wards (see Superspreaders & The Korean MERS Epidemiological Report).

This unprecedented nosocomial outbreak spread across 16 hospitals in South Korea, where more than 185 patients, family members and staff were infected (see June 2015 WHO MERS Situation Assessment For Korea), with at least 37 deaths.

Additionally, thousands of exposed individuals - while not infected - found themselves quarantined at home and undergoing daily medical checks for the 14 day incubation period.

While 99.999% of all returning Hajjis with respiratory symptoms will almost certainly have something far less exotic or dangerous than MERS, the experience of South Korea shows that it only takes one infected individual to slip through the cracks to spark a national crisis.

For more on the Korean experience, and how France handled their clinical management of suspected MERS cases in Paris between 2013 and 2016, you may wish to revisit last month's BMC Inf. Dis.: Clinical Management Of Suspected MERS-CoV Cases. 

And you'll find the CDC's advice to travelers, and clinicians, at MERS in the Arabian Peninsula.

While our focus today is on MERS, similar risks exist for a variety of emerging and re-emerging infectious diseases, including Ebola, Lassa Fever, Avian Flu, Nipah, and even Virus X  . . . the one that isn't on our radar screen yet.

In 2015. in TFAH Issue Brief: Preparing The United States For MERS-CoV & Other Emerging Infections, we looked at some of the steps that the United States needs to take to prepare for the arrival of MERS and other Emerging infections.   

Because, in our increasingly mobile and interconnected global society, it is really just a matter of time.