Thursday, March 22, 2018

Russia Reporting A Late Season Surge In H1N1


Two months ago, in Russia As An Outlier in This Year's Flu Epidemic, we looked at what had been (up to epi week 2) a lackluster flu season in Russia. In late January the rate of ILI & ARI morbidity was nearly 30% below the baseline for that time of year.
By mid-February (epi week 6_, in Russia : A Late Season Flu Surge & 3 NAI Resistant H1N1 Viruses, we saw the ILI & ARI rate finally exceed the baseline (by 6.6%) for the first time this winter. 
By last week (week 10) - after appearing to peak the previous week - the rate fell below the baseline once again.  Now last week's report appears to have been in error or complete, as week 11 has once again jumped to the highest level of activity (94.6 per 10 000 of population) for the season (30.3% over baseline). 
While a far cry from the severe season of 2016, this is the highest level of flu activity to be reported this late in March by the Russian Institute of Influenza in the past 7 years. 
Two months ago, the dominant strain in Russia was A(H3N2), while today H1N1 has now pulled into the lead. 

Given the atypical flu seasons we've been seeing the past 12 months around the globe (summer H3N2 outbreaks in Hong Kong & China, followed by Influenza B this winter, and back-to-back H3N2 seasons in the Northern Hemisphere), the unusually mild, and late arriving flu season in Russia this winter is worth noting. 

Some excerpts from this week's Russian Influenza Epidemiological Report (Week 11) follow:

Influenza and ARI morbidity data. Increase of influenza and other ARI activity was registered during week 11.2018 in Russia. The ILI & ARI incidence rate (94.6 per 10 000 of population) was above by 30.3% the nationalwide baseline.

Etiology of ILI & ARI morbidity. The overall percent of respiratory samples positive for influenza was estimated as 26.5%. Proportion of influenza A(H1N1)pdm09, A(H3N2), type A and type B viruses was estimated as 38.4%, 24.8%, 2.6% and 34.1%, respectively.

Antigenic characterization.
222 influenza viruses were characterized antigenically in Moscow and Saint-Petersburg NICs, including 65 influenza A(H1N1)pdm09 viruses, 44 influenza A(H3N2) strains and 113 influenza type B strains.
All influenza A(H1N1)pdm09 strains were related to influenza A/Michigan/45/2015, influenza A(H3N2) strains to A/Hong Kong/4801/2014 viruses. 97 influenza type B strains belonged to Yamagata lineage and were like B/Phuket/3073/2013 reference virus, 6 influenza type B strains belonged to Victoria lineage and were antigenically related to B/Brisbain/60/2008 strain.

Genetic characterization. Full-genome NGS of 58 influenza positive samples and viruses from 6 cities was conducted. 16 influenza A(H1N1)pdm09 viruses belonged to phylogenetic group 6B.1 with amino acid substitutions in HA S84N, S162N and I216T.
According to phylogenetic analisis of HA 18 of 22 tested influenza A(H3N2) viruses belonged to clade 3C.2a carring aa substitutions L3I, N144S, F159Y, K160T, N225D and Q311H in HA1. Four influenza A(H3N2) viruses belonged to genetic subgroup 3C.2a1 and carried aa substitutions K92R, N121K, T135K and H311Q.
2 influenza B viruses of Victoria-lineage belonged to genetic subgroup 1A (B/Brisbane/60/2008-like). All 18 influenza B viruses of Yamagata-lineage belonged to clade 3 (B/Phuket/3073/2013-like) and had substitution L172Q and M251V in HA1.

Susceptibility to antivirals.Most viruses were susceptible to NA inhibitors excluding three influenza A(H1N1)pdm09 strains isolated in Moscow which had H275Y amino acid substitution in NA responsible for highly reduced susceptibility to oseltamivir and zanamivir.
14 influenza strains tested in MUNANA-assay for antiviral resistance to NA inhibitors in RII NIC, including 3 A(H1N1)pdm09 strains isolated in St.Petersburg, 4 A(H3N2), two B Victoria strains and 5 B Yamagata viruses were susceptible to oseltamivir and zanamivir. All influenza A strains tested were resistant to rimantadine.

Percent of positive ARI cases of non-influenza etiology (PIV, adeno- and RSV) was estimated as 18.3% of investigated patients by IFA and 8.3% by PCR. Last weeks RSV dominated among ARI agents.

In sentinel surveillance system clinical samples from 144 SARI and ILI/ARI patients were investigated by rRT-PCR. 35 (44.3%) influenza cases were detected among SARI patients, including 8 influenza A(H1N1)pdm09 cases, 16 influenza A(H3N2) cases and 11 influenza B cases. Among ILI/ARI patients 20 (30.8%) influenza cases were detected, including 4 influenza A(H1N1)pdm09, 8 influenza A(H3N2) and 8 influenza B cases.

This late season surge in influenza activity - particularly in countries bordering Russia - has also been noted in the latest Joint ECDC - WHO/Europe weekly influenza Update.

Week 10/2018 (5-11 March 2018)

    • Influenza viruses continue to circulate widely in the Region, apart from some eastern European countries that have only recently reported increased activity.
    • Similar to the previous week, 50% of the individuals sampled from primary healthcare settings tested positive for influenza virus, despite the peak rate for the Region occurring in week 05/2018.
    • Both influenza virus types A and B were co-circulating with a higher proportion of type B viruses and with B/Yamagata continuing to be the dominant lineage.
    • Similar proportions of influenza type A and B viruses were reported in patients admitted to ICU, while the majority of severe cases reported this season have been due to influenza type B and occur in persons above the age of 15 years.

Although the Northern Hemisphere's flu season is clearly winding down, what happens over the next few weeks could still have some influence over what happens in the upcoming Southern Hemisphere flu season.

Eur. Resp.J.: Influenza & Pneumonia Infections Increase Risk Of Heart Attack and Stroke


For the past several years we've watched as a growing body of evidence has linked influenza and other respiratory infections to heart attacks and other cardiovascular incidents - particularly in the week following onset of infection.
While in January of this year, in NEJM: Acute Myocardial Infarction After Laboratory-Confirmed Influenza Infection, we looked at a report that found a `significant association' between recent (lab confirmed) influenza infection and Myocardial Infarction. 
In fact, they reported the odds of having a heart attack in the 7 days following influenza diagnosis went up 6-fold among the subjects in that study.
We've another study - published this week in the European Respiratory Journal - that also finds `substantially increased MI rates in the week after S.pneumoniae and influenza' while the risks of stroke was elevated for as much as 28 days.

First a link and the Abstract, followed by excerpts from a press release by the European Lung Foundation.
Laboratory-confirmed respiratory infections as triggers for acute myocardial infarction and stroke: a self-controlled case series analysis of national linked datasets from Scotland 
Charlotte Warren-Gash, Ruth Blackburn, Heather Whitaker, Jim McMenamin, Andrew C. Hayward 

European Respiratory Journal 2018; DOI: 10.1183/13993003.01794-2017


While acute respiratory infections can trigger cardiovascular events, the differential effect of specific organisms is unknown. This is important to guide vaccine policy.

Using national infection surveillance data linked to the Scottish Morbidity Record, we identified adults with a first myocardial infarction (MI) or stroke from 01/01/2004 to 31/12/2014 and a record of laboratory-confirmed respiratory infection during this period. Using self-controlled case series analysis, we generated age- and season-adjusted incidence ratios (IR) for MI (n=1,227) or stroke (n=762) after infections compared to baseline time.

We found substantially increased MI rates in the week after S.pneumoniae and influenza: adjusted IRs for days 1–3 were 5.98, 95% CI 2.47–14.4, and 9.80, 95% CI 2.7–40.5, respectively.
Rates of stroke after infection were similarly high and remained elevated to 28 days: day 1–3 adjusted IRs 12.3, 95% CI 5.48–27.7, and 7.82, 95% CI 1.07–56.9, for S.pneumoniae and influenza. Although other respiratory viruses were associated with raised point estimates for both outcomes, only the day 4–7 estimate for stroke reached statistical significance.

We showed a marked cardiovascular triggering effect of S.pneumoniae and influenza, which highlights the need for adequate pneumococcal and influenza vaccine uptake. Further research is needed into vascular effects of non-influenza respiratory viruses.


Laboratory-confirmed respiratory infections are linked to strokes and heart attacks in a Scottish population

 From the European Lung Foundation:

Flu and pneumonia infections increase risk of having a heart attack and stroke

European Lung Foundation

People who have had flu or pneumonia may be six times more likely to suffer from a heart attack or stroke in the days after infection, according to new research published in the European Respiratory Journal [1].
The research, funded by the Academy of Medical Sciences, is the largest study to look at the risk of heart attacks and strokes due to specific respiratory infections. It found that several different organisms that cause respiratory infections also increase heart attack and stroke risk, including S. pneumoniae bacteria and influenza.
The researchers say that the findings suggest that getting vaccinated against these two infections could also have a role in preventing heart attack and stroke, along with preventing infection in the first place.
In general, respiratory infections are thought to increase the risk of heart attack and stroke by causing inflammation, which can lead to the development of blood clots. The influenza virus and S.pneumoniae, the most common pneumonia causing bacteria, can also have harmful effects on the heart muscle.
The new research found that having flu or pneumonia increases the risk of having a heart attack for up to a week after infection, and the risk of having a stroke is increased for one month.
        (Continue . . . . )

As any paramedic, ER nurse, or doctor can tell you, heart attacks are more common during the winter than in the summer.

In fact, a 1998 study looked at the rate of heart attacks in the United States, and found that Acute Myocardial Infarctions (AMIs) run as much 53% higher during the winter months than than during the summer.
While cold weather combined with strenuous physical activity (like clearing snow from sidewalks) have often been blamed for this spike, even in balmy Southern California, studies have shown a 33% increase in heart attacks over the winter holidays.
Increasingly, the evidence points to a previously under appreciated side effect of our annual winter respiratory illness epidemic as being behind this increase in excess winter mortality.

All reasons why I am a proponent of getting the flu vaccine every year, and why I elected to take the Pneumovax 23 vaccine when it was offered by my doctor. 
While recommended for everyone over 65, the CDC has a long list of qualifying conditions (which includes smoking, diabetes, and a litany of immunocompromising conditions , etc.) for those under the age of 65.  
To see if you fall into any of these groups and should consider getting the vaccine, either visit the CDC's Pneumococcal Vaccination webpage or talk with your doctor. 

ECDC RRA On Measles In EU & Harvard Study On Mumps Vaccine

Credit ECDC


Measles, which was once almost a youth’s `rite of passage’, was declared `eliminated' (defined as `absence of continuous disease transmission for 12 months or more in a specific geographic area') in the United States in 2000, more than 35 years after the introduction of the first measles vaccine in 1963.
During the 1950s the US saw roughly 4 million infections which hospitalized nearly 50,000, and contributed to the deaths of several hundred every year.
Nevertheless, cases still occur, and in 2017 the CDC recorded 118 cases from 15 states and the District of Columbia who contracted the disease. They cite:
  • The majority of people who got measles were unvaccinated.
  • Measles is still common in many parts of the world including some countries in Europe, Asia, the Pacific, and Africa.
  • Travelers with measles continue to bring the disease into the U.S.
  • Measles can spread when it reaches a community in the U.S. where groups of people are unvaccinated.
As noted, measles is less controlled outside of the United States, and Europe continues to report large surges of cases every few years, involving not hundreds - but thousands - of cases.

Since 1999 EU countries have reported nearly 200,000 cases.

 With measles on the rise again early in 2018, the ECDC has published a new RRA (Rapid Risk Assessment).  First we've the ECDC news report, followed by a link to the full 13 page PDF report, after which I'll return with a postscript on new research on the Mumps vaccine.

ECDC Rapid Risk Assessment highlights young adults and healthcare workers as groups that are susceptible to measles, 21 March 2018

21 Mar 2018

ECDC assesses the risk of measles transmission in the EU/EEA in latest rapid risk assessment.

The latest ECDC rapid risk assessment on the risk of measles transmission in the EU/EEA highlights that vaccination coverage and occurrence of cases vary within countries and population groups. It points to the need for systems to identify and vaccinate young adults, who are increasingly affected and therefore increase measles circulation, but who may not be aware of their vaccination status. Finally, ECDC signals the frequency of cases amongst healthcare workers as a matter of concern and suggests that Member States may consider specific interventions to ensure this group is vaccinated.

    Measles cases occur unequally within countries

Data showing the distribution of measles cases within countries (Figure 1) highlights the importance of vaccination coverage of at least 95% of the general population throughout a whole country with two doses of measles-containing vaccine. This is recommended and necessary to ensure that measles circulation is interrupted, and that introduction of measles cases does not result in secondary cases. The availability of data at subnational level allows identification of geographical areas where measles cases are occurring and where targeted actions may be needed to identify unvaccinated individuals, increase coverage rates and carry out response activities.
    Measles increasingly affects young adults who may not be aware of their vaccination status

Some countries have seen an increasing proportion of cases among adults, prompting the need to consider actions to identify people or pockets of susceptible individuals who are incompletely vaccinated or not vaccinated at all. In light of current outbreaks in several EU countries, individuals who have not been vaccinated with two doses of measles-containing vaccine are at risk of contracting and further spreading measles, especially to infants who are too young to be vaccinated and are more vulnerable to complications from the disease.

Healthcare providers should consider recommending vaccination for all eligible individuals who are not immunised, or not fully immunised, in line with national recommendations. Any encounter with the healthcare system should be used as an opportunity for a catch-up vaccination against measles as well as other vaccine-preventable diseases.

    Frequency of measles cases amongst healthcare workers a matter of concern

The frequent occurrence of measles among healthcare workers in several EU/EEA countries is a matter of concern and Member States may consider specific interventions to address this, such as ensuring that all healthcare workers are immune to measles, with proof/documentation of immunity or immunization as a condition of enrolment into training and employment.

ECDC Rapid Risk Assessment highlights young adults and healthcare workers as groups that are susceptible to measles, 21 March 2018

21 Mar 2018

Given the current extent of measles circulation in the EU/EEA, the trend in recent years, and the fact that vaccination coverage for the first and second dose is suboptimal, there is a high risk of continued measles transmission with mutual exportation and importation between EU/EEA Member States and third countries.

Risk of measles transmission in the EU/EEA - EN - [PDF-1.44 MB]

Along with measles, another highly transmissible `childhood' disease - mumps - has been making a comeback in the United States in recent years, and not just in children.  Until 2005 - the mumps vaccine had been credited with reducing the incidence of mumps by about 99%. 

A study, published yesterday in Science Translational Medicine, suggests waning effectiveness of the mumps component in the MMWR vaccine may be behind the dramatic resurgence in mumps cases over the past dozen years. 
They report: `Synthesizing data from six studies of mumps vaccine effectiveness, we estimated that vaccine-derived immune protection against mumps wanes on average 27 years (95% confidence interval, 16 to 51 years) after vaccination.
First a link to the study, and then some excerpts from a Harvard Crimson report on the study.

Vaccine waning and mumps re-emergence in the United States

Joseph A. Lewnard1,* and  Yonatan H. Grad2,3,*

Science Translational Medicine 21 Mar 2018:
Vol. 10, Issue 433, eaao5945
DOI: 10.1126/scitranslmed.aao5945

Harvard Study Links Mumps Outbreaks to Waning Vaccine Immunity 

The recent spate of mumps outbreaks across the country, including one at Harvard, may be due to the waning effectiveness of the mumps vaccine, according to a new study published by two researchers at the Harvard School of Public Health.
Cases of mumps have been on the rise nationwide, according to the Centers for Disease Control and Prevention. In 2017, more than 5,000 people contracted the disease, up from fewer than 1,000 in 2012. College campuses have been hit particularly hard, which experts have previously attributed to the close contact between students.
Grad said he wanted to discover whether the increase in mumps cases was due to a new strain of mumps resistant to the vaccine—or due to the vaccine’s effectiveness wearing off as patients aged. Currently, federal recommendations call for two vaccinations: one between 12 and 15 months of age, and a second between four and six years.
“In our analysis, we saw that waning was consistent with what we were observing, whereas the appearance of a new strain that escaped the vaccine was not,” he said.
In the research paper, the authors suggest a third vaccination around age 18 as a possible means to reduce cases of mumps. The scientists are not the first to consider this idea: In light of recent research, the CDC recommended a third dose for at-risk populations in a January report.
Still, official recommendations do not call for all people to be routinely vaccinated at 18, which the authors say “should be assessed in clinical trials.”

(Continue . . . )

For more on measles, mumps, and the third element of the childhood disease trifecta - Pertussis - you may wish to revisit these blogs:

AMA Statement Supporting Stricter Requirements For School Vaccinations
CDC Telebriefing: Worst US Measles Outbreak In 20 Years

California: Pertussis Rising (Again)

NYC Health Department Investigating Measles Outbreak

ECDC: Risk Assessment On Measles Outbreak Aboard Cruise Ship

Wednesday, March 21, 2018

Germany: Schleswig-Holstein Ag Minister Confirms H5N6 On Hallig Suederoog


Although Germany reported the new H5N6 virus for the first time in a wild duck during the first week of January (see OIE Report), it hadn't - until today - reported this recent reassortment in poultry. 

The following announcement from the Schleswig-Holstein Government website, and describes an outbreak on the small island of Hallig Suederoog (pop. 2) off the northwest coast of Germany.

Avian Influenza on Hallig Süderoog

datum 03.21.2018
In a poultry farm with 57 chickens, turkeys, ducks and geese the avian influenza virus of subtype H5N6 has been detected.
Approximately one year after the last detection of avian influenza in Schleswig-Holstein has come again to an outbreak of notifiable animal disease. In a small animal husbandry on the holm Süderoog in the district of North Friesland experts from the Friedrich Loeffler Institute had detected the pathogen subtype H5N6. The 57 chickens, turkeys, ducks and geese must now be killed.
Restricted zones established

On the holm a restricted area was established after the outbreak. A complementary observation area includes the island of Pellworm. In these zones, strict security measures such as an obligation to keep poultry apply. In addition, the transport of live birds in the area is prohibited.
Strict security measures

The Environment Ministry urged all poultry farmers to comply with the prescribed safety regulations and for example, to feed their animals where wild birds do not have access. Feed, bedding and other items with which the poultry can come into contact should be kept away from wild birds. If it comes in a stable to increased animal deaths must be called a veterinarian to determine the cause. Dead wild birds such as ducks, geese, gulls and raptors should be reported to the veterinary or town clerk's office.

new subtype

The now proven pathogen subtype H5N6 is very similar to the subtype H5N8, which infected many animals in Europe in winter 2016/2017. H5N6 has so far been detected in Switzerland, the United Kingdom, Ireland, Sweden and Denmark. In January, the pathogen first appeared in a wild duck in Bavaria. It is not known that the virus can be transmitted to humans.

With migratory birds now headed north for the spring, countries along the flyways will need to stay alert for additional outbreaks.

J. Virology: Analysis Of A Swine Variant H1N1 Virus Associated With A Fatal Outcome


Novel flu viruses (like H5N1, H5N6, H7N9, and H10N8), are particularly worrisome because - while they haven't yet figured out how to spread efficiently among humans  - when they do jump to humans they tend to have a very high mortality rate. 
But going back 130 years, we've only seen human influenza pandemics (and seasonal flu epidemics) sparked by H1, H2, and H3 viruses (see  Are Influenza Pandemic Viruses Members Of An Exclusive Club?).
Granted, we've no clue what influenza subtypes might have circulated in humans before 1890, and there is some guesswork surrounding those prior to 1918.  But based on a relatively limited sample size - H1, H2, and H3 viruses are the most likely to produce a human pandemic.
Which is why, even though they tend to produce far lower mortality than novel flu, we keep a close eye on human, avian, and swine-origin H1, H2, and H3 viruses. 
Between 2005 and the end of 2010, the CDC  documented 19 human infections by swine origin influenza viruses (SOIV) across the United States, 12 of which were trH1N1 viruses, 6 were trH3N2, and 1 was trH1N2.
During the summer of 2011 a new strain of swine influenza  - originally dubbed trH3N2 but renamed H3N2v (swine variant influenza) – was discovered to have evolved in pigs. 
What made this virus different from the earlier trH3N2 novel strains was that it was a reassortant swine H3N2 which had acquired the matrix (M) gene from the 2009 H1N1 pandemic virus. The CDC has speculated that:
`This M gene may confer increased transmissibility to and among humans, compared to other variant influenza viruses.CDC HAN 2012
The CDC’s MMWR  in November of 2011 detailed the Iowa cases in a dispatch called Limited Human-to-Human Transmission of Novel Influenza A (H3N2) Virus — Iowa, November 2011.
By then  it was pretty apparent that this swine H3N2 virus had a greater affinity to human hosts than most of the other SOIVs we’d seen in the past (excluding the 2009 H1N1pdm virus).
A few more scattered cases occurred in Minnesota and West Virginia by year's end, and the virus was given a new name WHO/FAO/OIE: Call It A(H3N2)v, which raised the total for 2011 to a dozen cases reported around the country.
This was, in all likelihood, a substantial undercount with at least one estimate putting the number 200 times greater (see CID Journal: Estimates Of Human Infection From H3N2v (Jul 2011-Apr 2012).
The following summer (2012) the floodgates opened - and while still likely badly under counted - over a little more than two months more than 300 human swine variant infections were reported across 10 states.
Again, nearly all had direct contact with pigs at state and local fairs (see CID Journal: H3N2v Outbreaks In United States – 2012).
Although the number of reported swine variant infections dropped back to single digits for each of the next three years (2013, 2014, 2015) in 2016 we saw a renewed surge of cases (20+), and last year (2017) 67 cases were reported (see FluView Wk 49: Influenza Increasing - 1 Novel H3N2v Report From Iowa).

These swine variant viruses have also continued to evolve. Eighteen months ago an MMWR: Investigation Into H3N2v Outbreak In Ohio & Michigan - Summer 2016 revealed that 16 of the 18 cases analyzed belonged to a new genotype not previously detected in humans.

While most human infections have been either mild or moderate, a couple of deaths have been reported, including a fatal case in Ohio in 2015 (see FluView Week 17: Fatal Swine Variant (H1N1v) Case In Ohio).
Often the severity and outcome of an influenza infection is based on a person's preexisting conditions, or even host genetics (see  A Genetic Predisposition To Severe Flu Infection), but sometimes a severe outcome can be due to subtle changes in the virus. 
All of which brings us to a study by researchers at the Influenza Division, National Center for Immunization and Respiratory Diseases, CDC -  published this week in the Journal of Virology - that looks at the genetics and infectivity and transmissibility (in ferrets) of the swine origin virus that caused the death of the patient in Ohio in 2015.

Antigenically diverse swine-origin H1N1 variant influenza viruses exhibit differential ferret pathogenesis and transmission phenotypes

Joanna A. Pulit-Penaloza1, Joyce Jones1, Xiangjie Sun1, Yunho Jang1, Sharmi Thor1, Jessica A. Belser1, Natosha Zanders1, Hannah M. Creager1, Callie Ridenour1, Li Wang1, Thomas J. Stark1, Rebecca Garten1, Li-Mei Chen1, John Barnes1, Terrence M. Tumpey1, David E. Wentworth1, Taronna R. Maines1# and C. Todd Davis1#


Influenza A(H1) viruses circulating in swine represent an emerging virus threat as zoonotic infections occur sporadically following exposure to swine. A fatal infection caused by an H1N1 variant (H1N1v) virus was detected in a patient with reported exposure to swine and who presented with pneumonia, respiratory failure, and cardiac arrest. 

To understand the genetic and phenotypic characteristics of the virus, genome sequence analysis, antigenic characterization, and ferret pathogenesis and transmissibility experiments were performed. 

Antigenic analysis of the virus isolated from the fatal case, A/Ohio/09/2015, demonstrated significant antigenic drift away from classical swine H1N1 variant viruses and H1N1 pandemic 2009 viruses. A substitution in the H1 hemagglutinin (G155E) was identified that likely impacted antigenicity, and reverse genetics was employed to understand the molecular mechanism of antibody escape. 

Reversion of the substitution to 155G, in a reverse genetics A/Ohio/09/2015 virus, showed that this residue was central to the loss of hemagglutination inhibition by ferret antisera raised against a prototypical H1N1 pandemic 2009 virus (A/California/07/2009), as well as gamma lineage classical swine H1N1 viruses, demonstrating the importance of this residue for antibody recognition of this H1 lineage. 

When analyzed in the ferret model, A/Ohio/09/2015 and another H1N1v virus (A/Iowa/39/2015), as well as A/California/07/2009, replicated efficiently in the respiratory tract of ferrets.
The two H1N1v viruses transmitted efficiently among cohoused ferrets, but respiratory droplet transmission studies showed that A/California/07/2009 transmitted through the air more efficiently. Pre-existing immunity to A/California/07/2009 did not fully protect ferrets from challenge with A/Ohio/09/2015.

Human infections with classical swine influenza A(H1N1) viruses that circulate in pigs continue to occur in the United States following exposure to swine.
To understand the genetic and virologic characteristics of a virus (A/Ohio/09/2015) associated with a fatal infection and a virus associated with a non-fatal infection (A/Iowa/39/2015), we performed genome sequence analysis, antigenic testing, and pathogenicity and transmission studies in a ferret model. 

Reverse genetics was employed to identify a single antigenic site substitution (HA G155E) responsible for antigenic variation of A/Ohio/09/2015 compared to related classical swine influenza A(H1N1) viruses. Ferrets with pre-existing immunity to the pandemic A(H1N1) virus were challenged with A/Ohio/09/2015 demonstrating decreased protection. 

This data illustrates the potential for currently circulating swine influenza viruses to infect and cause illness in humans with pre-existing immunity to H1N1 pandemic 2009 viruses and a need for ongoing risk assessment and development of candidate vaccine viruses for improved pandemic preparedness.

Although swine-variant infections have been reported year-round, the prime `season' appears to be from early summer and into the fall, when millions of people visit state fairs and agricultural exhibits across the country.  
While most human infections are reported in the United States, that is likely due to our relatively high level of surveillance and testing, and not due to a paucity of porcine influenza around the globe. 
For more on swine-origin influenza, and the public health risks they pose, you may wish to revisit:
oonosis & PH: Survey Of Animal Exhibitor's KAP During Swine Variant Outbreak

EID Journal: Transmission Of Swine H3N2 To Humans At Agricultural Exhibits - Michigan & Ohio 2016
J. Virol: Novel Reassortant Human-like H3N2 & H3N1 Influenza A Viruses In Pigs
J. Virology: A Single Amino Acid Change Alters Transmissability Of EAH1N1 In Guinea Pigs

I&ORV: Triple-Reassortant Novel H3 Virus of Human/Swine Origin Established In Danish Pigs

Taiwan's Counterfeit AI Vaccine Trade


Taiwan - which  lies under the East-Asian Migratory Flyway - has been plagued with (mostly LPAI H5N2) outbreaks for years. But in 2015 Taiwan saw the arrival of at least 3 new HPAI strains of H5 - all apparently related to the H5N8 virus which first erupted in South Korea 12 months earlier.
Unlike Mainland China - which is the world's largest consumer of poultry AI vaccines - Taiwan prefers instead to use the OIE recommended methods of strict quarantine and culling.
That hasn't stopped desperate poultry farmers from circumventing the law - something we looked at a little over two years ago in Taiwan COA Warns Against Importation & Use Of AI Vaccines.

Last summer Taiwanese police arrested 9 people accused of making and selling - or buying - counterfeit pig vaccines At least 7,800 vials of this fake porcine  vaccine had been sold to 32 farmers, and nearly 400,000 pigs had  been injected.
Not only were these vaccines diluted to the point of being useless to prevent porcine circovirus (PCV), they were also contaminated with bacteria, and many of the vaccinated pigs died.
This report from Focus Taiwan.
Nine people charged in fake pig vaccine case 
2017/06/06 18:32:01
Taipei, June 6 (CNA) Nine people have been charged in a case involving the supply of fake vaccines to pig farmers, the Yunlin District Prosecutors' Office said Tuesday.

The nine individuals were indicted on June 2 on charges of fraud, making and selling counterfeit veterinary drugs, and forging or altering documents - offenses that violate the Veterinary Drugs Control Act and the Criminal Code, according to the prosecutors.

The investigation was launched following the sudden death of a number of piglets in Yunlin and Changhua and after prosecutors received a tipoff in March that dubious pig vaccines were being sold to farmers.

During the investigation, prosecutors found that two men had been purchasing genuine vaccines at a cost of NT$3,750 (US$124) per vial, diluting them with distilled water, and repackaging them.
(Continue . . . )

Aside from the bacterial contamination issue and the lack of protection afforded these `vaccinated' pigs, diluted vaccines pose an incredible risk of allowing viruses to replicate and evolve away from the vaccine strain, putting the entire pig population at risk.
But the story gets even worse today.
Based on Chinese language media reports overnight, last summer's arrests lead to an even larger investigation into counterfeit poultry vaccines, and this week additional arrests have been made.

According to multiple reports (see here, here, and here), the scheme involved the illicit collection of blood from (supposedly) previously infected and recovered poultry at a slaughterhouse.
The harvested blood was reportedly `centrifuged', and the serum collected - and after adding antibiotics and `other drugs' - injected as a vaccine.
It isn't clear how many birds already received this fake vaccine, but enough of this witch's brew vaccinate 500,000 birds was recovered by authorities.

Based on the video of the premises (see below), this operation was conducted under absolutely squalid and primitive conditions, and the resultant `vaccine' appears to have undergone absolutely no testing for purity, contents, or strength.

Frankly, if you wanted to spark a new  epizootic (or worse, a pandemic), it would be hard to come up with a better scheme.  One wonders how much this operation has contributed to the ongoing AI epizootic on the island.

Some (translated) excerpts from one the media reports follow:
Taiwan's unscrupulous peddlers made fake tens of millions of yuan worth of fake poultry flu
March 21, 2018 16:05 Taiwan , China

Unscrupulous traders sold fake black bird flu fake drugs, and the group "injection team" peddled them to the poultry industry and profited tens of millions of yuan. (Source: Taiwan "China Times")

China Taiwan Network March 21st According to Taiwan’s “China Times” report, Yunlin DPA seized two groups of illegal elements in Yunlin, Taoyuan, and Changhua. They made black heart avian influenza counterfeit drugs and formed “injection teams” everywhere. Selling to poultry farms will earn millions of dollars (NT, the same below). The whole case continued to expand in investigations.

The report said that when the prosecutor of the Yunlin Land Prosecutor's Office investigated the black heart pig vaccine case in 2017, he discovered that there were unscrupulous people who formed an "injection team" to sell black duck avian influenza animal counterfeit medicines to duck raisers and immediately reported to the Attorney General Cheng Mingqian, Zheng Mingqian. Instruct immediately to initiate investigation.

After prosecutor He Jinsheng directed the case handlers to conduct long-term cabling and search, on March 15 this year, the owner of Wu Xing, Dongzhi Township, Yunlin County was found to have collected bird blood from poultry farms that had survived the bird flu since 2015. The use of centrifuges to separate serum from blood and blood clots, and then add antibiotics and other unknown drugs to make bird flu known to prevent bird flu virus counterfeit animal drugs.

The prosecutor stated that a total of 544 fake drugs for black-hearted bird flu animals have been detained and estimated to be injectable with 1,000 birds per bottle. The quantity of counterfeit drugs could allow 540,000 birds to become poison-protected animals with viruses. Virus-infected animals that do not have the disease on their face, if found in the market, will cause more serious bird flu outbreaks. (China Taiwan Net Juanzi)

This investigation is reportedly ongoing, and more arrests appear likely.  Hopefully laboratory testing will provide additional information on virological legacy of this illicit operation.