How does interspecies transmission of influenza occur and what is the genus epidemicus for the 2009 swine influenza?

“about the end of April, suddenly a distemper arose, as if sent by some blast of the stars, which laid hold on very many together; that in the space of a week, above a thousand people fell sick together.”

~Willis 1658

Introduction

A new H1N1 influenza (Homeopathy Treatment for H1N1 Influenza) A with human, avian and swine genes (MacKenzie 2009) spread to humans this year, and is said to have pandemic potential.

Homeopaths treat epidemics and pandemic by establishing the genus epidemicus or epidemic similimum; that is, the medicine or small group of medicines which are the similimum to the epidemic disease rather than the individual. This is the most efficacious way of treating an epidemic/pandemic because the disease is of external origin and overcomes most people’s immune systems in much the same way (O’Reilly 1996, p. 139). The sooner the genus epidemicus for this influenza is established the better, as treating this influenza quickly and effectively is the best solution to curbing the spread of the infection.

There are two sections to this research. In the first section, a literature review of influenza A research and influenza pandemics will be conducted in order to establish how multi-strain, inter-specie influenzas occur and what factors stimulate concern for a pandemic. The time period to be covered is from the 1918 Spanish influenza to the present day. Influenzas prior to the 1918 influenza may not be included because very little is known about the genetic make-up of the virus cells, owing to the fact that influenza was not discovered to be a virus until 1932 (Potter 2008) and preserved samples from previous influenzas have not been found.

Since 1900 there have been three pandemics and three pandemic threats. The three pandemics were the 1819 Spanish influenza, the 1957 Asian influenza and the 1968 Hong Kong influenza. The three pandemic threats were the 1976 Swine influenza, the 1977 Russian influenza and the 1997 Avian influenza (U.S Department of Health and Human Services 2009).

The second section will be devoted to looking at the available symptomatology of the current H1N1 influenza to try to establish the epidemic similimum.

Interspecies transmission of influenza

The natural hosts of influenza are wild waterfowl, shore birds and gulls, but humans, swine, chickens, turkeys, mink and horses have developed influenza strains of their own over time (Reeves & Black 2001, p. 103) and recently influenza have been seen in other mammals such as cats and leopards (Nicholls 2006). Interspecies transmission of influenza does not occur easily between most species; swine are the exception (Reeves and Black 2001, p. 103). Swine are the key to interspecies influenza transmission as they are susceptible to influenzas from other species and can therefore act as a mixing vessel (Vivek and colleagues 2005-2009). Given that swine are the mixing vessel and that influenza is by nature a rapidly evolving virus (Nicholls 2006), it was only a matter of time before three genes mixed together to create a ‘triple re-assortment’ influenza.

See also

A Question on Homeoprophylaxis

Pandemics occur when an influenza mutates into a new strain which is easily transmitted between the target specie (Nicholls 2006). New influenza mutations are able to spread to a pandemic level because nobody has immunity to the virus from previous exposure (Mackenzie 2009). This information can be illustrated in characteristics of influenza A pandemics over the last century

The 1918 Spanish influenza was a H1N1 human/avian influenza (Nicholls 2006), and appears to have mutated directly from avian sources, as opposed to mutating from a circulating influenza. This is known because Jeffery Taubenberger and colleagues, in 2005, were able to put together the genetic sequence of the 1918 influenza from soldiers found in a preserved state from World War I who died of the Spanish influenza (Nicholls 2006).

The 1957 H2N2 Asian influenza and the 1968 H3N2 Hong Kong influenza were human/avian influenzas (Reeves & Black 2001, p. 103). However, they were circulating influenzas with multiple new avian genetic segments (Nicholls 2006).

The 1976 H1N1 Swine influenza threat was human/swine influenza combination (Enserink 2009), which erupted amongst soldiers at a New Jersey Army base but never spread any further (Gaydos, Top, Hodder and Russell 2006).

The 1977 H1N1 Russian influenza threat was of human/avian origin which affected people under 25 years of age in Russia and China. It was hypothesized that it affected this group because they had not been previously exposed to an H1N1 influenza; the 1918 H1N1 circulated until the mid 1950s, therefore people over 25 years of age had some immunity to the H1N1 influenza (Kilbourne 2005).

The 1997 and 1999 H5N1 Avian influenza affected a handful of people in Hong Kong and mutated directly from chickens; pigs were not the mixing vessel in this case. However, human-to-human transmission was poor and the virus fizzles out quickly (U.S Department of Health and Human services 2009).

The current H1N1 influenza is the first ‘triple re-assortment’ influenza which has human-to-human transmissibility (MacKenzie 2009). The surface proteins, haemagglutinin (H) and neuraminidase (N) are swine proteins, but the genes inside the virus cells are of swine, avian and human origin (MacKenzie 2009). This triple re-assortment has been circulating in hog farms since 1998, so it has been known for some time now that this mutation of influenza would affect humans eventually (MacKenzie 2009). Scientists have theorized that this influenza spread from a local pig farm at ground zero in Mexico. The local pigs did not display symptoms though because they have already developed immunity to this strain (Aldhous 2009).

The Genus epidemicus

The following homeopathic forums were searched for postings from homeopaths who have seen cases of the current 2009 H1N1 influenza:

abchomeopathy
Hpathy Homeopathy Forums
www.homeopathyworldcommunity.ning.com/forum
www.youtube.com

So far no-one has posted any reliable differentiating symptoms. There is one posting in homeopathyworldcommunity.ning.com, in a swine flu thread, in which a woman details her symptoms. However, she never specifies whether she was diagnosed as having swine flu.

The best information available as of 26 May 2009 is Dr Manish Bhatia’s posting on hpathy.com in which he comments that the 2009 swine influenza appears to have strong gastrointestinal symptoms and therefore suggests that the genus epidemicus could be Aconite, Baptisia, Arsenicum album, Ipecac, Eupatorium perfoliatum or Gelsemium.

The symptomatology so far is: (Bhatia 2009)

·Fever
·Muscles aches
·Lethargy
·Coughing
·Headache
·Sore throat
·Runny nose
·Nausea
·Vomiting
·Diarrhea
·Lack of appetite

All of these symptoms are common influenza symptoms and therefore useless when searching for the genus epidemicus. At this point, repertorising these symptoms would be a waste of time as the rubrics are still too general (see Appendix A for list of possible rubrics).

Typically, influenza mutates over the course of the flu season and affects groups of people in waves. If the flu does not fizzle out after the first wave, subsequent waves can be more aggressive. This is particularly a problem with pandemics, as the new virus adapts to the new host over the course of the season. This was certainly the case with the 1918 pandemic (MacKenzie 2009).

With only a few cases in Australia at the moment (16 as of 25 May (World Health Organization 2009)), Australian homeopaths may not have the opportunity to treat this Swine influenza unless a second wave affects the greater population. Furthermore, viruses are prone to change over the course of the flu season, so the genus epidemicus would have to be reassessed continuously.

Results

Interspecies transmission
Interspecies transmission of influenza occurs mainly through pigs, as they appear to be susceptible to many species strains and act as a mixing vessel and ideal source for generating a new pandemic. Influenzas have developed directly from birds and not involved pigs at all, but they do not appear to spread amongst humans effectively enough to generate a pandemic yet. Therefore, while pigs remain the key to spreading new influenza pandemics between species, pandemics directly from other species may be possible in the future.

Genus Epidemicus
Homeopaths can still only speculate on the genus epidemicus as there are too few postings of specific symptoms to be able to properly differentiate between possible genus epidemicus medicines.
The most likely medicines at this stage are: Aconite, Baptisia, Arsenicum album, Ipecac, Eupatorium perfoliatum and Gelsemium. However, none has yet been confirmed to have successfully treated the H1N1 swine influenza. At any rate, as the influenza season progresses, the genus epidemicus may have to be reassessed.

Conclusion

Through a literature review of influenza A and Influenza pandemics it has been established that interspecies transmission of influenza occurs mainly via swine. Swine are susceptible to the influenzas of many species, and therefore act as a mixing vessel. At this stage swine also appear to be the key ingredient in the development of an influenza pandemic amongst humans. An avian influenza, without the aid of swine, infected humans in 1997 and 1999 in Hong Kong, but the human-to-human transmission of the virus was too poor to cause a pandemic. However, avian influenza remains a future threat as the virus will continue to mutate.