The role of zoonoses to the major epidemics of the past and present
People undermine their health with intensive breeding of consumption animals. We remember still a single farm with chickens and pigs on the farm and cows in the pasture. Increasingly we see grain silos appear with large livestock farming, whose pigs, chickens or cows never outside come. Diseases, which can be transmitted from animals to humans, are the result.
Examples of zoonoses are plentiful:
In the 14th century of the early Middle Ages farmers in Mongolia have attracted rats and mice by their grain stocks and consequently have transferred the rats and their fleas pasteurella pestis (bubonic and pneumonic plague) to local people. The marmot is the most common reservoir for pasteurella pestis in eastern Asia. At the siege of a Genoese trade office Kaffa on the Black Sea by the Mongols hundreds of corpses of plague victims were catapults shot into the besieged city to infect the inhabitants of the city. The Genoese seamen were hit by the plague in 1345. The survivors with ships fled to Sicily and Genoa. The disease was so moved over Europe. The Genoese fleet infected first people of Messina in Sicily. From Genoa the disease spread through the extensive trade network throughout Europe. The bubonic and pneumonic plague was so moved to the Mediterranean and the Black Death killed 25 million people, or 50% of the European population.
Tropical birds were imported late in the history, after the colonization of South America and the Caribbean, as public entertainment to Europe. Only with the increase of shipping traffic and air cargo, tropical birds could easily be imported and traded. The largest epidemic occurred in 1929-1930 after the import of infected parrots from Argentina to Europe. Hundreds of people became seriously ill and 20% died after an acute fulminant disease. Initially, in many countries strict import restrictions were set. Not much later parrots were again massively imported. Bird shows and breeders produced an explosive growth of this popular pastime. Tropical bird breeders and pigeon breeders have Chlamydia psittaci and Chlamydia pneumoniae spread over Western Europe. The domestication of parrots in Western Europe has led to the adaptation of the psittacosis "virus", first in the flocks of the pigeon breeders who often kept also tropical birds. With many tropical bird breeders the 'psittacosis virus' adapted and disease that occurred in humans was less violent. Chlamydia psittacosis has adapted in Western Europe and ornithosis and Chlamydia pneumonia were the result of this. Chlamydia pneumoniae is adjusted so that this microorganism now also passes from human to human through the airways and is now so prevalent in society that 98% have been infected. Repeated infections with Chlamydiae, primarily occurring with bird breeders and bird keepers, cause chronic respiratory diseases and cause lung cancer in humans.
Particulate matter with an aerodynamic diameter of around 2.5 micrometers, is the main health hazard of (indoor) air pollution. The amount of particles from 10 to 0.5 micrometer has been proven to be elevated in bird keeping households. Lung cancer is increased in the last century. Recently (2012) has been proven in a laboratory animal model that spraying Chlamydia pneumoniae in the airways caused in 15% of the animals lung cancer.
With Christmas, turkeys and infectious poultry products from the U.S. New Mexico, avian flu (so-called Spanish flu) has been transmitted by the troop transports in World War I to Europe. Two thirds of bacteria and viruses that can cause human disease originate from animals.
Beware All Kinds of Flu
Highly pathogenic viral diseases like bird flu and swine flu have strong links with intensified farming. The highly pathogenic H5N1 virus emerged during a time of massive expansion of the poultry industry in the Far East. Birds are virus disseminators above all other animals. Waterfowl spread avian influenza. Caged birds spread herpes viruses, retroviruses and the smallest bacteria such as Chlamydiae. There have been outbreaks of avian influenza on egg farms. Free-range birds came into contact with the battery egg-layer hens, so one might come to the conclusion that the infection was via virus-shedding wild birds. Wild ducks spread all avian influenza virus strains. The overwhelming majority of studies of different designs (including all the mortality and cancer incident studies) indicate at least a 30% excess risk of lung cancer in meat and poultry plant workers, even after controlling for smoking. Evidence points to animal oncogenic microorganisms as one of main causes. This has important public health implications because the general population is also widely exposed.
Laying hens, chickens and eggs are contaminated with oncogenic viruses
Battery laying hens have retroviruses attracted of the mice on the grain stocks. Eggs were therefore permanently infected. By consumption of undercooked egg-proteins, there is an increase of ovarian cancer, breast cancer and prostate cancer in humans. Retrovirus secreting mice also come into contact with free-range chickens. Free-range chickens are often kept outdoors so that the risk of contamination through the pollution of food on the ground may be greater from mice feces. In the winter months, mice more than likely go to aviaries and poultry farms to collect scraps of food. Virus bearing and virus-secreting mice, cereals, chicken feed, poultry infection, vertical transmission of retroviruses via eggs and processing of raw protein in Bavarian cream and other confectionery products occur, man being the terminus. In practically all poultry farms retroviruses, which are closely related to mouse mammary tumor retrovirus (MMTV), can be found. Laying hens have a high rate of ovarian tumors (Johnson 2013), but such tumors are uncommon in hens less than 2 years old. Oviductal and ovarian tumors are generally not differentiated, and genital tumors occur mainly in hens above the age at which most are slaughtered. In commercial poultry operations, hens are usually sacrificed after their first year as layers, aged between 22 and 24 months. Humans are commonly exposed to potentially oncogenic viruses that naturally infect and are frequently endemic in animals, which are part of the food chain, such as laying hens, chickens and eggs. Raw egg proteins very often contain retrovirus. Egg protein is often undercooked.There is now widespread immune tolerance in humans to retrovirus. Latent persistent mammary infections with retrovirus are very common. Practically all milk contains retrovirus antigen. After the menopause biological regression occurs with immune reduction, which may result in tumor growth. Retrovirus has been found in breast cancer cells, removed from women but not in healthy breast tissue. Recently it was shown that the retrovirus is able to lodge itself in human mammary gland cells and to multiply.
Broiler chickens spread multi-drug resistant bacteria
The meat of broilers is increasingly infected with antibiotic-resistant bacteria such as MRSA staphylococcal and VRE intestinal bacteria. More antibiotics are given to farm animals than to sick humans. Intensive pig and poultry farmers and their household members, chicken meat and pig meat are increasingly infected with multi-resistant bacteria.
Repeated urinary tract infections in women are often the result of a zoonosis
Chicken is contaminated with coliform bacteria and infection in the kitchen is hardly to prevent. Bloody diarrhea after eating undercooked chicken or pork, for example, after a barbecue, is a dangerous phenomenon. In some cases, bloody diarrhea is caused by multi-drug resistant Coli bacteria. Especially in women these intestinal bacteria reach the bladder (Yamamoto S 1997). The bacteria attach to the bladder wall, and hardly respond to treatment with antibiotics. The urine is bloody. Not infrequently, these bacteria go higher and reach the kidneys via the ureter. Entero Hemolytic E. coli bacteria (EHEC) can cause severe renal failure.
The mad cow disease (BSE ) was spread through infected meat in Europe At the end of last century meat and bone meal, as sheep heads, were given to British cows. Natural herbivores – grass and hay eating cows – turned into carnivores, feeding them meat and bone meal, in stead of grass, for faster growing and more financial profit.
Fatter beef, chicken and pig meat contains more saturated animal fat
Anchovies from the southeastern Pacific Ocean are sold for animal feed in Europe’s factory farms. Chicken nuggets or pork chops can have a strange aroma. Around one third of the total fish catch is being fed to farmed animals, usually farmed fish, pigs and chickens. The animals fatten and grow faster in order to gain more profit and to shorten the slaughter time. Over the last decades, the production of fish oil and meal has removed around 20-30 million tons of fish from the south-eastern Pacific Ocean, anchovies, herring, mackerel and sprat species.
Intensive cattle, pig and poultry farming by feeding the animals with soya meal and even fish meal and low doses of antibiotic growth promoters fatten the animals and let them grow faster. Fatter beef meat, chicken meat and pig meat contains more saturated animal fat and cause more welfare diseases like cerebro-vascular disease, obesity and diabetes.
Colistin-resistant E.coli bacteria are already found in China
Colistin is widely used in Chinese livestock food, and this use probably led bacteria to evolve and gain resistance to the drug. The deadly pandrug resistant strain was later discovered in Europe, Afriaca, South America and Canada.
Intensive goat farming causes spread of Q fever
Goat feces and dirty bedding straw were shoveled up and carried outside by the farmers to fertilize their fields. In this way the Coxiella bacteria became airborne and infected people in the Netherlands.
Bush meat and slaughter of chimpanzees are seen as the cause of the global spread of AIDS (SIV/HIV viruses) HIV spread to humans through human consumption of the meat of wild animals (chimpanzee and gorilla) in Central Africa. During the 20th century, commercial hunting using firearms and wire snares to supply lodging and oil exploration operation concessions along new roadway networks has dramatically increased the catch in Central African forests. Annually, it is estimated that 579 million wild animals are caught and consumed in the Congo basin, equaling 4.5 million tons of bushmeat.
Zika virus was first identified in 1947
Yellow fever researchers working in the Zika forest in Uganda stumbled onto it. They had a macaque in a cage and it developed a febrile illness from something that was transmissible. The virus was described as Zika virus in 1952 and then found in people a couple of years later. Monkeys are susceptible for the virus. When it was a flu-like illness confined to some regions in Africa, Zika wasn’t a high priority so research hasn’t been extensive. The health risk for humans in areas where the virus is circulating (areas where there are Aedes egpyti, malaria mosquitoes) was very low. Most people that are infected don’t get sick at all, and when they do, they usually get only mild signs of illness that resolve on their own. In the past few years, Zika virus has emerged in the Americas, particularly Brazil. Very recently, a link between infection of pregnant women and birth defects - babies born with small heads and brains (microcephaly) has been reported, predominantly in Brazil.
The severe Acute Respiratory Syndrome (SARS) is provoked by a coronavirus and emerged in southern Chinese province of Guangdong (Canton) in November 2002. The worldwide outbreak of SARS was seeded from a single person on a single day on a Hong Kong hotel. A physician from Guangdong, had attended a wedding. As guests departed, the virus coughed by one man spread to five countries within 24 hours. Within months, the virus spread to 30 countries on six continents, causing 8,096 probable cases and 774 deaths (WHO2004). In the past, a trip around the world took a year; today, we and our viral baggage can circle the globe in 24 hours. Guangdong authorities cull thousands of civet cats and other wild animals in January 2004 and permanently ban their trade and human consumption. The researchers found that human and civet cat viruses had the same genetic profile after testing six SARS-carrying civet cats from a restaurant in early 2004, where a female employed had been found infected with SARS virus. WHO experts also discovered evidence of the virus in cages in a restaurant where a SARS patient ate civet meat. Sadly, Chinese people have a taste for a large array of wild animals, fact that threatens a lot the biodiversity but also exposes people disease transmitted from animals to humans, and the civet cat is considered a delicacy in Southern China. In fact, in rural China, the animals are still being sold in markets.
Dromedary Camel Flu
from virus spreading young dromedary camels, is possibly the latest outcome of dromedary camel breeding in the Arabian Peninsula. There is a rapid rise in reported infections with Middle East Respiratory Syndrome Coronavirus (MERS-CoV). MERS-CoV infected today (3 Feb 2016) over 1,290 people and caused 551 deaths (fatality rate 42%).The disease has been seen primarily in the Arabian Peninsula countries with Saudi Arabia and the United Arab Emirates. The WHO Emergency Committee on MERS-CoV announced that its concern had “significantly increased”, with particular worries over recent evidence that the infection is spreading in hospitals and close patient contacts.
In 2013, flying over the Arabian Peninsula, I saw the integrated crop circles of Saudi Arabia. Saudi farmers are fueling the production of grains in the desert by mining underground reserves of water. Some of that water dates back 20,000 years, to the last ice age, when more temperate conditions filled aquifers. On the ground, these circles are as wide as the aquifers are deep, about a kilometer, and are formed by the use of center-pivot irrigation sprinklers that draw on the groundwater. Many of the crops are grown to feed a bustling cattle industry. Camels are rarely used as a means of transport. Dromedary camels are bred for their milk and meat and to participate in camel races. The Saudi Kingdom has implemented a multifaceted program to provide vast supplies of water, necessary to achieve the spectacular growth of the agricultural sector. Vast underground waterreservoirs have been tapped through deep wells. So the desert was transformed into fertile farmland.
Dromedary camel flu is endemic amongst young dromedary camels in Saudi Arabia. Sick dromedary camels shed corona viruses from their nose and sometimes in stool. Only recently people and dromedary camels share the same corona viruses. Could it be that the corona virus first adapted in the herds of the camel breeders, with greater concentrations of young livestock dromedary camels. The breeding and weaning season could be a factor. Young camels are more susceptible to camel flu, because of their lower immunity status, and they facilitate virus amplification. Nowadays the MERS-CoV circulates from human to human and is less virulent. These humanized corona viruses pass through the airways and become more and more prevalent in society. Without stopping transmission from camels, we will continue to see more human cases in the Middle East, some of whom will travel outside of the region. With the annual Hajj Pilgrimage to Mecca in October, more than 2 millions of Muslims, from more than 180 countries, are at risk to catch MERS-CoV and spread it out. Saudi authorities are warning their citizens not to drink unpasteurized camel milk and to wear gloves when caring for the beasts. The ubiquity of the animals, their importance to the region’s economy and their popularity suggest camel-to-person transmission of MERS-CoV will continue to occur.