H5N1 is considered one of the most pathogenic flu viruses on the planet killing more than 50% of those who contract it. So far there have only been clusters of human to human transmission, usually amounts family members or those living within close proximity to each other. Even amongst these clusters the original source has always been bird, usually poultry.
Since the experiments on H5N1 back in 2012, where the virus was manipulated in a lab there have been hundreds more human cases, again the mortality rate has been upwards of 50%.
Although those experiments were slated as dangerous they did show that the virus only needs a few mutations to turn into a flu virus that spreads as easily as other flu viruses. These mutations can occur spontaneously over time, or they can occur by genetic reassortment. Put simply genetic reassortment occurs when two flu viruses get together and swap genetic material. If H5N1 is in the same household as a circulating flu strain and both get into the same person at the same time that would provide a pathway for the mutations to occur. By the infected person passing on the circulating flu to another person, a further chance for mutation would occur and so on until the H5N1 virus either: combines completely with the circulating strain to form a totally new flu strain or the two strains swap some genetic material. Neither is good news.
There are three types of flu, A, B and C. A is the worst, B the one in the middle and C the mildest. The virus looks like a spike ball under the microscope. The A and B flu viruses have two types of spikes that cover their surface – the haemagglutinin (H) and the neuraminidase (N). You get infected by flu because the spikes on the H are like microscopic grappling hooks and they attach themselves to receptor cells. At the appropriate time the N takes out the receptor cells from these newly formed balls of virus, which bursts the package open allowing the virus to ‘escape’ and proliferate and that’s what makes you sick.
Among influenza A viruses there are 17 different types of H, haemagglutinin, from H1 to H17 and nine different types of N, neuraminidase, from N1 to N9. Each virus has one type of H (such as H1) and one type of N (such as N1).
For classification and risk assessment purposes H5 influenza strains are considered to be HPAI – Highly Pathogenic Avian Influenzas. Many reports even from the government just refer to H5 HPAI without listing which N they are. It is the H that causes the trouble, the N just spreads it around.
Right that’s the science. Now the problem.
Some of the required mutations that will make H5N1 transmissible from human to human are taking place in nature…which puts the virus a step closer to having epidemic, (local clusters) endemic, (constantly in the area) and pandemic potential.
H5N1 is spreading. Most people think that China and some areas of the Middle East are the main areas affected but that’s not the case. They are the areas that most human cases have occurred in but it has been recorded in many countries. This is a list of the countries that USDA APHIS (United States Department of Agriculture: Animal and Plant Health Inspection Service) consider at risk from H5N1:
Regions APHIS considers affected with highly pathogenic avian influenza (HPAI) of any subtype.
9 CFR 94.6 (a)(2)
China, People’s Republic of
Hong Kong (Special Administrative Region of the People’s Republic of China)
Korea, Democratic People’s Republic of
Korea, Republic of
Lao People’s Democratic Republic
Macau (Special Administrative Region of the People’s Republic of China)
South Africa, Republic of
South Sudan, Republic of
This list was last updated on September 1st 2016. Since then there has been a worrying addition… Syria.
CIDRAP (Center for Infectious Disease Research and Policy) published a report yesterday (26/09/16) from the FAO (Food and Agriculture Organisation) that states:
Recent highly pathogenic H5N1 avian influenza outbreaks in Iraq and Lebanon pose a risk to other countries because of political instability and a host of other factors, such as wild bird migration and wintering habits. Countries at highest risk are Iran, Israel, Jordan, Syria, and Turkey, according to the group’s recent 8-page report.
Meanwhile, Lebanon confirmed H5N1 in April, affecting several farms in the eastern part of the country close to the Syrian border where refugees are settled. The investigation suggested illegal poultry movement as the source of the outbreak.
Given earlier H5N1 outbreaks in the region and high levels of poultry production in the countries surrounding Iraq, there is a risk that H5N1 could become established and spread in the region, the FAO said.
ALL diseases spread far easier in overcrowded and unsanitary conditions, and refugee camps are both. These countries are on the migratory path for birds, birds that can pick up H5N1 and carry it with them around the world. The overcrowding in these camps means that people are living in very close contact with thousands, sometimes tens of thousands of other people. Lack of adequate nutrition also means their immunity to disease is not as good as it could be and this makes them far more susceptible to viruses. When the circulating flu strain hits the refugee camps, or cities such as Aleppo that have no effective infrastructure the circumstances are bordering on ideal for the circulating flu and H5N1 to co-exist in close proximity and ultimately for patient zero ( the first person in which a genetic reassortment takes place) to contract both flu viruses in the same timeframe.
Massive migration from Syria and the surrounding area, is a problem across Europe. The United States and Canada have also agreed to take refugees from the area. Without a trace of xenophobia any country accepting refugees from these areas could be allowing a hell of a lot more than people cross their borders.
Syria itself most likely already has H5N1, but we don’t know about it because the monitoring is not in place due to the conditions in the country.
The CIDRAP report goes on to say:
Political instability has resulted in a large displacement of people and animals, with most refugees settling in agricultural areas. The FAO also said that continuing violence in the area has hampered farmers’ cross-border trade.
Other factors the FAO noted are that migratory birds concentrate in Iraq and Lebanon as they prepare to fly to wintering areas in the Middle East. Drier weather patterns in Mediterranean coastal areas could also push birds toward wetter areas of Iraq and Kurdistan, where congregating flocks could spread avian flu viruses. In Lebanon, migratory bird hunting is an important socioeconomic activity, which could pose a threat of virus transmission to people or domestic poultry.
The FAO also pointed out several other vulnerabilities, including differences in veterinary capacity, ranging from the prompt response to H5N1 by Lebanese authorities to weak services in Syria because of civil unrest.
For the region as a whole, the FAO said the overall risk was medium, with medium uncertainty. However, it put Iran, Jordan, Syria, and Turkey at highest risk. Though no outbreaks have been reported in Syria, it is likely that H5N1 has already been introduced to poultry populations there, according to the report.
The CDC reports that H5 (sub-type not listed) HPAI infections have been reported in 21 states since December 2014. To clarify, 21 states have reported cases of the H5 strain of Highly Pathogenic Avian Influenza since December 2014.
These H5 HPAI viruses can also mutate in exactly the same way as any other virus mutates, there is no difference at all to the mechanisms that cause them to move from ‘bird flu’ to human flu. Like seasonal circulating flu they appear more often in the birds in the winter.
As the incidence of these viruses continue to increase it’s imperative that you take precautions to protect yourself as best you can from getting any form of flu and I’ll be writing an article about how to do that tomorrow.