From the Black Death to the Age of Epidemics

Two health headlines just caught my eye:

Life Improved After Black Death, Study Finds
and
Are We At The Dawn Of The Age of Epidemics?

A new study shows surviving Europeans lived longer after the Black Death ravaged the population. Before the plague, only 10% of people lived past age 70 - but after the Black Death, more than 20% of people lived to be over 70.

"The Age of Epidemics" reviews just 11 current outbreaks and epidemics (there are more), from Mers and Ebola to polio and bovine leukemia. [Did you know about 38% of beef herds, 84% of dairy herds, and 100% of large-scale dairy operation herds are infected with bovine leukemia in the United States - and it's found in human breast tissue?] Never mind dengue fever and the bird flu's.

So what's the real message here? There's a black cloud on the horizon but it has a silver lining? The fit survive -or- Survivors are more fit than they were before infection?

What do YOU think? …I have a feeling people are stronger -in every way- after they assimilate diseases. As painful as that may be.

It Got Better: Life Improved After Black Death, Study Finds

The Black Death, a plague that first devastated Europe in the 1300s, had a silver lining. After the ravages of the disease, surviving Europeans lived longer, a new study finds.

….In the centuries before the Black Death, about 10 percent of people lived past age 70, said study researcher Sharon DeWitte, a biological anthropologist at the University of South Carolina. In the centuries after, more than 20 percent of people lived past that age.

Are We At The Dawn Of The Age of Epidemics?

Over the past several weeks and months, we've seen a startling number of disease outbreaks pop up around the globe. It's a trend that's not completely surprising — one that could characterize the coming decades as the Age of Epidemics. Here are some of the scariest new diseases you need to know about.

The First Case of MERS in the U.S.

WHO Declares Polio a Public Health Emergency

Measles On the Rise

Chikungunya Virus is Proliferating Rapidly in the Caribbean

Dengue Fever Continues to Spread

Ebola Ravages West Africa

The H5N1 Avian Flu Is Mutating in Bangladesh

New Kind of Bird Flu Has Been Found in Antarctic Penguins

Bovine Leukemia Is Transmissible to Humans

A Mysterious Kidney Disease Is Afflicting Male Farmworkers in Central America

MRSA and the Pending Antibiotic Apocalypse

a reply to: soficrow

Fascinating. Funnily enough, this article that you quoted seems very similar to what Jehovah's Witnesses say is a sign of the end times. Not to say that you should research Jehovah's Witnesses, but that there is a parallel.

More like, the strong survive and they breed to create more strong offspring.

Look at what happens in populations of organisms regularly treated with toxins that wipe nearly all of them out. Nearly. The ones who are left are super resistant, super strong and breed more like themselves. I'm not just talking about bacteria, but look at common household pests like cockroaches. There are roaches in NY that can't easily be killed by pesticides anymore and rats that are Coumadin resistant.

originally posted by: ketsuko
More like, the strong survive and they breed to create more strong offspring.

Look at what happens in populations of organisms regularly treated with toxins that wipe nearly all of them out. Nearly. The ones who are left are super resistant, super strong and breed more like themselves. I'm not just talking about bacteria, but look at common household pests like cockroaches. There are roaches in NY that can't easily be killed by pesticides anymore and rats that are Coumadin resistant.

The organisms treated with toxins develop resistance (they mutate) and become "stronger." Exposure is essential to the process.

Also of note: Once successful resistance develops in a single individual organism, the resistance genes spread horizontally in the population like a cold - not vertically from generation to generation in the bloodline.

Not sayin' resistance and immunity works the same way with complex organisms, but the fact is, we do not know how the immune system works.

a reply to: soficrow

So what's the real message here? There's a black cloud on the horizon but it has a silver lining? The fit survive -or- Survivors are more fit than they were before infection?

The Black death was spread by overcrowding. After it wiped out a massive part of the population the ones who were left were not swimming around in as much filth as before. Many of the survivors carries a gene mutation that made them almost immune to the disease. The same gene mutation make those people less likely to catch HIV.

originally posted by: PhoenixOD
a reply to: soficrow

So what's the real message here? There's a black cloud on the horizon but it has a silver lining? The fit survive -or- Survivors are more fit than they were before infection?

...Many of the survivors carries a gene mutation that made them almost immune to the disease.

Infection with the Black Death may have resulted in the gene mutation (genetic integration and assimilation) and thus, made survivors stronger and more "fit."

....As you may know, the human genome contains genetic material from many viruses and bacteria. Much of the assimilation dates back as long ago as 40 million years but some may be more recent. For example:

Unexpected Inheritance: Multiple Integrations of Ancient Bornavirus and Ebolavirus/Marburgvirus Sequences in Vertebrate Genomes

….In 19 of the tested vertebrate species, we discovered as many as 80 high-confidence examples of genomic DNA sequences that appear to be derived, as long ago as 40 million years, from ancestral members of 4 currently circulating virus families with single strand RNA genomes. Surprisingly, almost all of the sequences are related to only two families in the Order Mononegavirales: the Bornaviruses and the Filoviruses, which cause lethal neurological disease and hemorrhagic fevers, respectively. ….The conservation of relatively long open reading frames for several of the endogenous sequences, the virus-like protein regions represented, and a potential correlation between their presence and a species' resistance to the diseases caused by these pathogens, are consistent with the notion that their products provide some important biological advantage to the species. ….the examples described here should be considered a low estimate of the number of such integration events that have persisted over evolutionary time scales. Clearly, the sources of genetic information in vertebrate genomes are much more diverse than previously suspected.

…..a separately derived primate lineage (comprising marmosets, macaques, chimps, and humans) contains endogenous BDV gene N-related sequences integrated into seven different places in the genomes. …..In the primate line these sites first appear in the present day marmosets and have been retained over forty million years from a common ancestor of marmosets and humans (Figure 2). ……several integrations show signs of strong positive selection, namely those related to the BDV N gene in humans, microbats, rodents, and other animals, and both the EBOV/MARV NP and VP35 gene-related integrations in bats and tarsier. Some integration events, including the BDV N-like sequences in humans (e.g. hsEBLN-1) and the EBOV VP35-like sequences in microbats (mlEEL35) have maintained nearly full-length open reading frames (Table 2). The probability of having no stop codon in the longest of these, the BDV gene N-like integration in humans, is one in eight hundred, suggesting that at some time, past or present, there was strong selective pressure to keep and express this ancestral viral gene.

a reply to: soficrow

Its a possibility but just being immune to a disease and being more 'fit' because of it isn't a given.

Whats interesting about the black death is that a bunch of bodies were discovered not long ago (in the UK i think) that had been put in mass graves because they dies of the plague. So they extracted the teeth and ran DNA analysis on the virus and found that it was exactly the same as the strain of black death that keeps popping up nowadays. So the scientists were left with the question of why this strain isnt currently wiping out half the world. They came up with the hypothesis that over crowding and bad sanitation was the missing factor.

a reply to: PhoenixOD

They may have missed the obvious.

Lateral gene transfer (LGT) from bacteria to animals occurs more frequently than was appreciated prior to the advent of genome sequencing.

Bacterial DNA in Human Genomes

A new study finds strong evidence that bacteria can transfer genes into human genomes

….Danchin agrees that the results need to be validated but said, “…. I think LGT happens much more frequently than we imagine but, most of the time, is just not detectable.”

Bacteria-Human Somatic Cell Lateral Gene Transfer Is Enriched in Cancer Samples

….There are 10× more bacterial cells in the human body than there are human cells that are part of the human microbiome. Many of those bacteria are in constant, intimate contact with human cells. We sought to establish if bacterial cells insert their own DNA into the human genome. Such random mutations could cause disease in the same manner that mutagens like UV rays from the sun or chemicals in cigarettes induce mutations. We detected the integration of bacterial DNA in the human genome more readily in tumors than normal samples.

Infectious Disease as an Evolutionary Paradigm

The basic principles of genetics and evolution apply equally to human hosts and to emerging infections, in which foodborne outbreaks play an important and growing role. However, we are dealing with a very complicated coevolutionary process in which infectious agent outcomes range from mutual annihilation to mutual integration and resynthesis of a new species.

a reply to: PhoenixOD

...just being immune to a disease and being more 'fit' because of it isn't a given

Depends how you define "fit" of course - but I would say being immune to common and even rare diseases definitely qualifies as 'fitness.'

As well, given that disease organisms respond to environmental change and mutate far more quickly than humans, and accepting that "everything is connected," seems not so bad in the large view that they can share their adaptations with us.