(Survival Manual/6. Medical/b) Disease/Pandemic timelines)
1. Historic pandemics
• 430 BC, The Peloponnesian War Pestilence: The very first pandemic in recorded history was described by Thucydides. In 430 BC, during the Peloponnesian war between Athens and Sparta, the Greek historian told of a great pestilence (thought to be either Typhus or Bubonic plague) that wiped out over 30,000 of the citizens of Athens (roughly 33%-66% of all Athenians died).
• 165AD, The Antonine Plague: In 165 AD, Greek physician Galen described an ancient pandemic, now thought to be smallpox, that was brought to Rome by soldiers returning from Mesopotamia. The disease was named after Marcus Aurelius Antoninus, one of two Roman emperors who died from it. At its height, the disease killed some 5,000 people a day in Rome. By the time the disease ran its course some 15 years later, a total of 5 million people were dead.
• 541-542 The Plague of Justinian: In 541-542 AD, there was an outbreak of a deadly disease in the Byzantine Empire. At the height of the infection, the disease, named the Plague of Justinian after the reigning emperor Justinian I, killed 10,000 people in Constantinople every day. With no room nor time to bury them, bodies were left stacked in the open. By the end of the outbreak, nearly half of the inhabitants of the city were dead. Historians believe that this outbreak decimated up to a quarter of human population in the eastern Mediterranean.
• In 1200 AD, China’s population was reliably reported to be about 123 million; 200 years later it had plummeted to some 65 million (47% reduction, 1 of 2). Reportedly, vast country sided was empty. No crops were being raised. Now 800 years later it’s difficult to be sure, but this dramatic dieback was probably due to the effects of plagues and famines that followed.
• 1340s, The Black Death (Plague): After the Plague of Justinian, there were many sporadic outbreaks of the plague, but none as severe as the Black Death of the 14th century. The Black Death took a heavy toll on Europe. The fatality was recorded at over 25 million people or 25% of the entire population. The Black Death came in three forms: the bubonic, pneumonic, and septicemic plague. The first, the bubonic plague, was the most common: people with this disease have buboes or enlarged lymphatic glands that turn black (caused by decaying of the skin while the person is still alive). Without treatment, bubonic plague kills about half of those infected within 3 to 7 days.
• Ca 1500, During the 3 decade prior to 1520, when Hernan Cortez landed in Mexico, Smallpox wiped out an estimated 15 million Aztecs.
• Between 1500 until about 1520, some 10 million Europeans died from a more virulent form of Syphilis than exists today.
• 1700s: Influenza pandemics in 1729-1730, 1732-1733, 1781-1782.
• 1781: Major epidemic causing high mortality among the elderly spreads across Russia from Asia.
• 1817-2011 (and continuing) Cholera: 8 pandemics; hundreds of thousands killed worldwide. In the 19th century, Cholera became the world’s first truly global disease in a series of epidemics that proved to be a watershed for the history of plumbing. The major cholera pandemics are generally listed as: First: 1817-1823, Second: 1829-1851, Third: 1852-1859, Fourth: 1863-1879, Fifth: 1881-1896, Sixth: 1899-1923: Seventh: 1961- 1970, and some would argue that we are in the Eighth: 1991 to the present. Each pandemic, save the last, was accompanied by many thousands of deaths. As recently as 1947, 20,500 of 30,000 people infected in Egypt died.
• 1830: A 2nd major epidemic (previous similar pandemic 39 years earlier, in 1781) causing high mortality among the elderly spread across Russia from Asia.
• 1793, Yellow Fever killed 15% of Philadelphia’s population in 1793.
• 1918, The Spanish Flu: In March 1918, during the last months of World War I, an unusually virulent and deadly flu virus was identified in a US military camp in Kansas. Just 6 months later, the flu had become a worldwide pandemic in all continents. When the Spanish Flu pandemic was over, about 1 billion people or half the world’s population had contracted it. It was perhaps, the most lethal
pandemic in the history of humankind: between 20 and 100 million people were killed, more the number killed in the war itself.
• Between 1917-1921, rural Russia lost an estimated 10 million people out of a population of 85 million (12% reduction, 1 in 8), not as battlefield casualties, but as a direct result of famine and disease.
Minimally, 3 million are thought to have died from Typhus.
• In 1947, during the chaos of their struggle for independence, an estimated 1 million Indians died in the world’s worst Malaria epidemic.
• As late as 1940, immediately before the wise spread introduction of antibiotics, some 13,000 Americans still died annually from Syphilis. AIDS by contrast killed about 16,000 people in the US in 1999.
• 1981 – 2011 (and continuing) AIDS: Has killed 25 million people worldwide. Acquired Immune Deficiency Syndrome (AIDS) has led to the deaths of more than 25 million people since it was first recognized in 1981, making it one of the most destructive epidemics in recorded history.
Note: The highest historical death rates in an community from plagues and disease is 60%.
Note: While the following articles were written about the H1N1 Swine Flu, they should be understood as a metaphor for communicable human diseases in general.
__A. History of swine flu, H1N1
In 2009 the swine flu emerged as a massive threat to global health. It seemed to come out of nowhere, but our timeline explains how the origins of the H1N1 pandemic go back more than a century to 1889.
Prior to 1889
The main flu virus circulating in humans has been from the H1 family. But in 1889, a new strain of H2 flu emerged in Russia and spread around the world, killing about 1 million people. Thereafter, H2 replaced H1 in humans. Such replacements seem to be a regular feature of flu pandemics. People born before 1889, who had been exposed to H1 flu, had some immunity to it. This afforded them some protection in the deadly H1N1 epidemic of 1918. Those born after 1889 did not have any immunity to H1.
The “Spanish flu” epidemic of 1918 kills at least 50 million people worldwide. It is caused by an H1N1 virus which evolves directly from a bird flu into a human flu.
After a mild wave of infections in the summer, the epidemic goes global: one-third of the population eventually get sick. Although most cases are mild, any sufferers develop a rapidly fatal infection deep in their lungs. People born before 1889 are less susceptible, thanks to their previous exposure to H1N1.
Most deaths are caused by bacterial lung infections that move in after the virus.
Modern antibiotics might mean that a re-run of the 1918 pandemic would be less dangerous.
After 1919, the descendants of the H1N1 virus continue to circulate and cause seasonal flu outbreaks in humans – and pigs.
Swine flu is first isolated from a pig in Iowa.
The first human flu virus is isolated at Mill Hill in London. When given to ferrets, it produces a disease whose symptoms are all but identical to the Iowan pig virus. But ferrets that have had the human virus are not fully immune to the pig virus, showing that the two viruses have already started to evolve apart.
An H2N2 virus causes the “Asian” flu pandemic, completely displacing the H1N1 viruses that have been circulating in humans since 1918. The pandemic is fairly mild, killing 1 to 1.5 million people worldwide.
The virus is produced by a reassortment, in which human-adapted H1N1 swaps genes with an H2N2 bird flu. The new H and N surface proteins mean most people do not have antibodies to the virus, allowing it to go pandemic. However, its human-adapted genes mean it is not as lethal to humans as the 1918 virus, which came, with few changes, from birds.
People tend to mount the best immune response to the first kind of flu virus they experience. Because of this, people born before 1957, whose first experience of flu would have been the H1N1 viruses then in circulation, have some immunity to the 2009 H1N1 strain causing the current pandemic. People born after the 1957 pandemic do not have this immunity.
An H3N2 virus causes the “Hong Kong” flu pandemic, which is even milder than the Asian flu, killing an estimated 0.75 million to 1 million people worldwide. (I contracted the Hong Kong flu and am fortunately still here to tell you, that in no way, did I consider it ‘milder’ than any other instance of the ‘flu’ I’ve had in the following 43 years. -Mr Larry).
The virus only differs from H2N2 in one of its surface proteins, the H; since many people still have antibodies to the unchanged N2 protein, its effects are less severe. But because H3N2 completely replaces H2N2 in people, no one born since 1968 has any immunity to H2.
Researchers Graham Laver and Robert Webster discover that waterfowl are the natural hosts of influenza viruses. The birds harbour strains unknown in humans that could reassort with human strains and give rise to new human pandemics.
An H1N1 virus jumps from pigs to humans and kills a US army recruit. However the virus does not spread beyond the army base and fizzles out without triggering a pandemic.
Nevertheless, fears of a replay of the 1918 pandemic lead to 48 million people being hastily vaccinated against the swine flu virus. The vaccine is associated with an unusual number of cases of Guillain-Barré syndrome: 532 people get it, and 25 die.
An H1N1 virus appears in north-east China and starts circulating in humans. It causes seasonal flu in every subsequent year. No one knows where it came from, though it looks like an H1N1 that circulated in the Soviet Union in 1950 and some suspect it escaped in a laboratory accident.
The virus causes a mild flu pandemic, which mainly affects people born after H1N1 flu disappeared in 1957. However, the real surprise is that it does not displace the previous, and more virulent, seasonal flu, H3N2. Instead, it continues circulating alongside it.
The antibodies people produce after being infected by this new seasonal H1N1 do not protect against 2009 H1N1. However, infections also trigger another reaction called cell-mediated immunity, in which certain white blood cells target and destroy infected cells. Tests of the 2009 H1N1 pandemic vaccine show that, unlike antibodies, cell-mediated immunity to seasonal H1N1 may help protect against the pandemic virus. This does not prevent disease altogether, but can reduce its severity
The predecessor of the 2009 H1N1 swine flu virus emerges in the US . It is a hybrid of human, bird and swine flu viruses, and by 1999 it is the dominant flu strain in US pigs.
US pig farms try to control it with vaccines, but these attempts are largely ineffective because the virus evolves too rapidly, changing the surface proteins targeted by the vaccine while keeping its internal genes unchanged. The 2009 pandemic virus is a variant on this 1998 flu, and behaves the same way.
H5N1 flu, first identified as a threat to humans in Hong Kong in 1997, spreads from Asia around the world, apparently carried by wild birds. While this “bird flu” proves deadly to humans, killing more than half of its victims, it is kept in check by its inability to spread readily from human to human. H5N1 is also found in pigs in Indonesia, raising fears that it might reassort with other human flu viruses that pigs can harbor.
The threat posed by bird flu leads to the first real efforts to be made at pandemic planning: governments start to stockpile antiviral drugs, and the world’s drug companies start doing serious research on pandemic vaccines. These plans are made with the highly lethal H5N1 in mind, meaning that they are not always appropriate for the 2009 pandemic.
__B. Flu pandemics come in three waves… (and so did the Black Plague, but in waves separated by years instead of months)
The graph (see top of page) comes from a CDC analysis of the 1918 Spanish flu pandemic. As you can see from the graph, there were three waves: June 1918, Oct-Dec 1918, and Feb-Mar 1919. The worst was the Fall 1918 wave.
If we look back at the four previous major flu pandemics: 1) 1889, 2) Spanish flu pandemic of 1918, 3) Asian flu pandemic of 1957, and 4) Hong Kong flu pandemic of 1968 — they all followed the same pattern. A spring wave of relatively mild illness was followed by a second wave, a few months later, of a much more virulent disease. However, in all but the 1918 case, the Fall wave was still fairly mild.
Thus, based on history, we can expect the modern pandemics to fizzle around July (except in the Southern Hemisphere), but then return in a more virulent form in the fall. The fear is that we’ll follow the 1918 pattern, and the Fall wave will be extremely virulent (easily spread and highly lethal).
2. Timeline of Human Flu Pandemics
(Including human cases of avian and swine influenza viruses.)
Recent major pandemics
The appearance of new influenza strains in the human population:
“Spanish flu” H1N1 The most devastating flu pandemic in recent history, killing more than 500,000 people in the United States, and 20 million to 50 million people worldwide.
“Asian flu” H2N2 First identified in China, this virus caused roughly 70,000 deaths in the United States during the 1957-58 season. Because this strain has not circulated in humans since 1968, no one under 30 years old has immunity to this strain.
“Hong Kong flu” H3N2 First detected in Hong Kong, this virus caused roughly 34,000 deaths in the United States during the 1968-69 season. H3N2 viruses still circulate today.
Four soldiers in a US army base in New Jersey are infected with swine influenza, resulting in one death.
1977 Appearance of a new influenza strain in humans,
“Russian flu” H1N1. Isolated in northern China, this virus was similar to the virus that spread before 1957. For this reason, individuals born before 1957 were generally protected; however children and young adults born after that year were not because they had no prior immunity.
1997 Appearance of a new influenza strain in humans
H5N1 The first time an influenza virus was found to be transmitted directly from birds to people, with infections linked to exposure to poultry markets. Eighteen people in Hong Kong were hospitalized, six of whom died.
1999 Appearance of a new influenza strain in humans
H9N2 Appeared for the first time in humans. It caused illness in two children in Hong Kong, with poultry being the probable source.
2002 Appearance of a new influenza strain in humans
H7N2 vidence of infection is found in one person in Virginia following a poultry outbreak.
2003 Appearance of a new influenza strain in humans
H5N1 Caused two Hong Kong family members to be hospitalized after a visit to China, killing one of them, a 33-year-old man. (A third family member died while in China of an undiagnosed respiratory illness.)
• H7N7 In the first reported cases of this strain in humans, 89 people in the Netherlands, most of whom were poultry workers, became ill with eye infections or flu-like symptoms. A veterinarian who visited one of the affected poultry farms died.
• H7N2 Caused a person to be hospitalized in New York.
• H9N2 Caused illness in one child in Hong Kong.
2004 Appearance of a new influenza strain in humans
• H5N1 Caused illness in 47 people in Thailand and Vietnam, 34 of whom died. Researchers are especially concerned because this flu strain, which is quite deadly, is becoming endemic in Asia.
• H7N3 Is reported for the first time in humans. The strain caused illness in two poultry workers in Canada.
• H10N7 Is reported for the first time in humans. It caused illness in two infants in Egypt. One child’s father is a poultry merchant.
H5N1 The first case of human infection with H5N1 arises in Cambodia in February. By May, WHO reports 4 Cambodian cases, all fatal. Indonesia reports its first case, which is fatal, in July. Over the next three months, 7 cases of laboratory-confirmed H5N1 infection in Indonesia, and 4 deaths, occur.
On December 30, WHO reports a cumulative total of 142 laboratory-confirmed cases of H5N1 infection worldwide, all in Asia, with 74 deaths. Asian countries in which human infection with H5N1 has been detected: Thailand, Vietnam, Cambodia, Indonesia and China.
H5N1 In early January, two human cases of H5N1 infection, both fatal, are reported in rural areas of Eastern Turkey, while cases in China continues to spread. As of January 25, China reports a total of
10 cases, with 7 deaths. On January 30, Iraq reports its first case of human H5N1 infection, which was fatal, to the WHO.
• In March, the WHO confirmed seven cases of human H5N1 infection, and five deaths, in Azerbaijan. In April, WHO confirmed four cases of human H5N1 infection, and two fatalities, in Egypt.
• In May, the WHO confirmed a case of human H5N1 infection in the African nation of Djibouti. This was the first confirmed case in sub-Saharan Africa. Throughout 2006, 115 human cases of H5N1 infection occur, with 79 deaths.
• H5N1 In early January, two human cases of H5N1 are confirmed in Indonesia. By the end of 2007, 88 confirmed cases occur in Indonesia, Cambodia, China, Lao People’s Democratic Republic, Myanmar, Nigeria, Pakistan and Vietnam, with 59 deaths.
• H7N7 In May, four cases of H7N7 avian influenza were confirmed in the United Kingdom among individuals exposed to infected poultry.
H5N1 On May 28, Bangladesh reports its first case of human H5N1 infection to the WHO. By the end of the year, 40 cases are confirmed in Bangladesh, Cambodia, China, Egypt, Indonesia and Vietnam.
• H5N1 On January 7, Indonesia confirmed a new case of human infection with H5N1 influenza. Since that time, new cases have been identified in Egypt, China, Indonesia and Vietnam.
• Appearance of a new influenza strain in humans: H1N1 In April, human infection with a new strain of H1N1 influenza is confirmed in Mexico. Within weeks, human infections spread to the United States and cases begin occurring in other regions around the world.
3. One Flu Season: The Timeline of a mild H1N1 Influenza outbreak
GENEVA, Aug 10, 2010 – The following is a timeline of the spread of swine flu, officially known as influenza A(H1N1), after the World Health Organization announced the end of the pandemic, more than a year after it was declared.
2009: April 24: The WHO announces that around 800 suspected cases of so-called swine flu have been recorded in Mexico, along with seven cases in the United States.
April 25: The WHO warns that the virus, identified as a member of the H1N1 family, has “pandemic potential.”
April 26: Health authorities step up vigilance measures around the world.
April 27: First three cases are confirmed in Europe. The WHO raises its level of alert to four from three on a scale of six.
April 28: The first cases in the Middle East.
April 29: A 23-month-old Mexican child is the first confirmed fatality in the United States. The WHO raises its alert level to five and calls for preparations for an “imminent” pandemic.
April 30: WHO adopts the term “influenza A(H1N1)” after veterinary experts point out that the virus is not occurring among pigs.
May 2: The virus makes its appearance in Asia.
May 20: The WHO says that A(H1N1) has officially contaminated 10,243 people in 41 countries and killed 80 people.
June 11: The WHO raises its alert to the maximum level six and declares A(H1N1) the first flu pandemic of the 21st century. The UN body calls on pharmaceutical laboratories to produce vaccines against the virus.
June 14: One death in Scotland, the first death outside the American continent.
June 29: Denmark reports the first case of resistance to Tamiflu, considered to be the most effective treatment for the flu by the WHO. The virus continues to spread throughout the world with 11,000
new cases in three days.
July 17: The WHO says that the swine flu pandemic is moving around the globe at an “unprecedented” speed.
August 28: The WHO says that the swine flu virus has supplanted other viruses to establish itself as the most prevalent strain of flu.
September 21: China becomes the first country in the world to launch a mass vaccination campaign.
September 24: The WHO drops its forecast of needed vaccines to three billion doses from five billion a year.
October 30: The flu has killed at least 5,700 people around the world, hitting in particular the northern hemisphere where vaccination campaigns are being put into place with the approach of winter.
December 18: The number of dead passes 10,000, according to the WHO.
January 22: The WHO says the pandemic is in decline. It has killed at least 14,000 people around the world since emerging.
April 21: A year after the outbreak, the epidemic has spread to 213 countries and territories. The WHO and national health authorities come under criticism for dramatizing the threat of the flu and for the billions of dollars (euros) spent on buying medicines and vaccines.
June 8: WHO chief Margaret Chan denies that she has been influenced by pharmaceutical firms in managing the flu crisis and denies allegations of a conflict of interest.
August 10: The WHO declares the pandemic over.
4. The Seasonal Flu Vaccine
A seasonal vaccine is distributed routinely every year.
• Unlike during the 2009 flu season, when you needed to get two vaccines, the 2009 H1N1 and the seasonal vaccine, during the 2010 and 2011 flu season you only need the seasonal vaccine.
• The 2010-2011 flu vaccine protects against an influenza A H3N2 virus, an influenza B virus and the 2009 H1N1 virus that caused so much illness last season.
• Everyone 6 months of age and older should get vaccinated against the flu.
• Vaccination of high risk persons is especially important to decrease their risk of severe flu illness.
• Vaccination is important for health care workers, and other people who live with or care for high risk people to keep from spreading flu to high risk people.
• Children younger than 6 months are at high risk of serious flu illness, but are too young to be vaccinated. People who care for them should be vaccinated.
• As the flu season approaches, many people are wondering if they are in jeopardy of catching H1N1. At this stage in the game, the Centers for Disease Control (CDC) predict that the H1N1 virus will continue to spread along with the regular seasonal viruses. Because viruses can and do mutate, it also is possible for new flu strains to appear during the 2010-2011 season.
• The CDC said that H1N1, also known as swine flu, was responsible the first influenza pandemic in 40 years. According to the World Health Organization (WHO), an influenza pandemic occurs when a new influenza virus emerges and spreads across the world at a time when most people don’t have immunity to that strain.
• On a more positive note, scientists at the NationalInstitute of Allergy and Infectious Diseases (NIAID) estimate that 183 millionAmericans have developed some immunity to the 2009 H1N1 virus, either throughexposure, infection or immunization during the previous flu season.