20110306-leprosy cdc mdb_aspergillos.jpg
leprosy bacteria
Leprosy is a disfiguring infection that attacks the central nervous system and is caused by a bacteria in the skin and nerve tissues. How the bacteria infects is still unknown It may enter the body through respiratory tract or threw open cuts. Unlike most bacteria, which like warm places, the leprosy bacteria prefers cool places, and thrives in the skin, nerves near the skin and the surface membranes of the mouth

Leprosy, now more commonly known as Hansen’s disease, strikes several hundred thousand people every year. The number of new cases has decreased from 5.4 million cases worldwide in 1987 to 940,000 cases in 1997 to 760,000 in 2002.Brazil, Madagascar, Mozambique, Tanzania and Nepal had 90 percent of all new cases. The disease is still found in India and Southeast Asia but has largely been eradicated from the developed world. Leprosy is expected to be wiped out soon. There are hopes that the disease will be eradicated early in the 21st century.

Leprosy was originally thought to have originated on the Indian subcontinent and was carried to the west by Alexander the Great’s armies. Recent genetic research however seems to indicate that the disease originated in northern Africa or the Middle East. Described as a curse from God, it was given a fair amount of coverage in the Bible and other religious texts. Among the miracles performed by Jesus was the curing of lepers. Leper colonies existed in the West until relatively recently.

Most people who have leprosy don't know they have it do and have few symptoms. Early symptoms include skin lesions and tender joints. Later symptoms include nerve damage, thickening and folding of the skin, and atrophy of hands and feet.

Leprosy victims lose their feeling as a result of nerve damage. They do not fell pain and don't notice burns, cuts, bruises or the pressure sores caused by the disease. Victims often lose their fingers and toes and facial features because they don’t feel injuries to them. Untreated leprosy can cause blindness and serious disfigurement. In severe cases, hands and feet curl inward, hair disappears, the lips drop and the nose flattens and collapses. The face of many victims resembles lion.

More than 95 percent of people who get leprosy can fight the disease with their immune systems. Otherwise the disease can be cured with a prolonged treatment of multiple-drug therapy (dapsone, rifampin and ciofazimine). In many places this treatment is provided free by the World Health Organization. A cheap, one-dose leprosy treatment has recently been made available.

Buruli ulcer is an infection from the bacterium family that causes leprosy and tuberculosis. Symptoms include severely deforming ulcers in limbs, which can lead to amputation.

Websites and Resources Centers for Disease Control and Prevention (CDC) cdc.gov/DiseasesConditions ; World Health Organization (WHO) fact sheets who.int/news-room/fact-sheets ; National Institute of Health (NIH) Library Medline Plus medlineplus/healthtopics ; Merck Manuals (detailed info many diseases) merckmanuals.com/professional/index


The bubonic plague, known as the "Black Death" in the Middle Ages, is a highly infectious and often fatal disease that is spread mostly by rodents. It killed around 25 million people worldwide in the 1300s. The disease is spread largely through flea bites. The bacteria that causes the diseases can cause gangrene, seizures and fever. Pneumonic plague is the deadlier variant of plague. It is spread by coughing and can kill victims in 24 hours. Pneumonic plague often affects rural areas. It is closely related to bubonic plague. “ivian Tan, the spokeswoman for the World Health Organization in China, said the disease is curable if treated early with antibiotics.

Plague is enzootic in rural rodent population in several continents with occasional outbreaks among commensal rodents in villages and small towns. Urban outbreaks are rare and limited. Plague is deadly in 100 percent of cases if not treated with antibiotics with 12 to 24 hours after the onset of symptoms. It is highly contagious. There is a plague vaccine consisting of three shots (dose 2 is given four weeks after dose 1 and dose 3 is given 3 to 6 months after dose 2). The data on the efficacy of the vaccination is still incomplete.

The World Health Organization (WHO) reports about 1,000 to 3,000 plague cases each years. In the 2000s they were mostly in Madagascar, Tanzania. Mozambique, Malawi, Uganda and the Democratic Republic of Congo. Only 100 to 200 people have died of the plague over the past 20 years but doctors say the disease should not be underestimated. It has popped up in different countries in recent years and has been shifting to Africa and is virtually impossible to wipe because of the way it is transmitted among animals. Michael Begon, a plague expert at Liverpool University, wrote in a medical journal: “Although the number of human cases of plague is relatively low, it would be a mistake to overlook its threat to humanity, because of the disease’s inherent communicability, rapid spread, rapid clinical course and high mortality rate if left untreated.

The plague is very rare but occurs in the United States. In 2013, a 7-year-old girl in Colorado contracted the disease — and survived — after she came in contact with a dead squirrel while camping in southwest Colorado. A similar infection, pneumonic plague, was reported in a patient in Colorado in July 2014

Leptospira is a disease that causes fever, jaundice, blood in the urine and inflammation of the kidneys. It is often transferred to humans by rodents.


Poliomyelitis, or polio, is a contagious viral disease that can invade the spinal cord and brain and can cause muscle weakness and atrophy. In severe cases it can cause paralysis in a matter of hours, difficulty breathing or result in death. There are three types of the disease: 1,2 and 3. The name poliomyelitis comes from the Greek terms “polios” , meaning gray, and “myelon” , for marrow, a reference to the gray area of the spinal chord that affected by the disease.

Polio is usually transmitted through contaminated food and water. It invades the nervous system and often leads to permanent paralysis. It can be prevented by immunization. The polio virus lives and reproduces in the intestines and is spread from person to person by ingestion of anything contaminated with infected fecal matter. It often found in places where people live in crowded conditions with poor sanitation and is spread through waterways in which children play or drinking or bathing water tainted with contaminated feces. The highest transmission rates typically have taken place in the summer or when the weather has been hot. One problem with polio is that is it highly infectious but only a few sufferers have symptoms and those that don’t can transmit the disease.

Polio has been around for some time. Club feet, shortened legs and shrunken femurs found on 5,000-year-old ancient Egyptian mummies are believed to have been caused by the disease. Up until a vaccine for polio was invented by Jonas Salk in 1954, polio crippled and killed thousands of children and condemned thousands more to iron lungs. Among its victims was U.S. President Franklin Roosevelt. Polio has been eradicated in most of the developed world but remains in some places in the developing world.

The polio vaccine can be taken orally, often in form drops administered from an eye dropper. It is made from a live, weakened strain of the virus. In 1957, Dr, Albert Sabin developed oral vaccines for each of the three types of polio. The most common type used today is a vaccine first used in the 1960s that combines three vaccines invented by Sabin. At least four doses of the vaccine are needed to reach maximum effectiveness. In rare cases outbreaks of polio can be caused by the vaccine.

Eradicating Polio

WHO Director General Chan and Bill Gates lead
discussion on Polio
Polio has nearly been eradicated but wiping it off the map completely has proved to be problematic and expensive. A campaign to eradicate polio was launched in 1988. the original goal was to eradicate the disease by 1998. That goal proved to be elusive, then the goal was extended to 2005 but still not reached. In the process $5 billion was consumed, which probably could have been better spent fighting other diseases.

The last wild case of polio in the United States was in 1979. In South America the disease was eradicated in 1994. In Europe it was eradicated in 2002. In 2004, there were only 1,200 wild cases worldwide. They were mostly type 1 and to a lesser extent type 2. The last cases of type 2 polio were reported in 1999.

The Global Polio Eradication Initiative — a partnership of WHO, UNICEF, Rotary International, and CDC — was launched in 1988 with the goal of eliminating polio by 2000. More than $4 billion has been spent and more than billion children have been immunized in an aggressive vaccination programs and number of new cases worldwide from decreases from 350,000 cases in 1988 to fewer than 2,000 cased in four countries — India, Pakistan, Nigeria and Afghanistan — as of 2005. But it has not been eradicated. If polio is eradicated it will be only the second disease to be eliminated from the face of the earth. The first was smallpox.

Polio was eradicated in Egypt and Niger in 2005. This was regarded as major victory because the diseases had held on their for a long time in spite of a great efforts to wipe out. India reported only 64 cases on polio in 2005, compared to 130 in 2004. Pakistan reported 27 cases in 2005, compared to 48 in 2004. Polio is getting close enough to complete eradications that health officials are beginning to make plans of where to stockpile the virus if it is wiped out. Remaining trouble spots are in northern Nigeria,, remote regions of Pakistan and Afghanistan.

Come Back of Polio

In recent years polio has made a come back in India, Pakistan, and Nigeria. Particularly alarming was an outbreak in Nigeria in 2003 that spread to Sudan, Ethiopia, other places in Africa, Yemen and Indonesia. were caused by strains brought in from Nigeria. The disease is though to have been carried from Nigeria to Sudan by workers and from there was carried by Hajj pilgrims to Mecca in Saudi Arabia, who transmitted it to other pilgrims who took the disease to their homes in Yemen and Indonesia, where it took hold in places where immunization rates were only 25 percent to 30 percent.

Other outbreaks have occurred. In 2005, polio was recorded in 27 countries, including 21 where it was reintroduced by people who had traveled to infected areas . In places where it was reintroduced countrywide vaccination campaigns quickly stopped transmission in 15 of the 21 countries. Progress has also been made in some places using vaccines from the 1950s designed for each of the three different types of polio.

About 93 percent of the cases reported in 2005 were either in Nigeria or originated there. The campaign to eradicate polio in Nigeria has been hampered by rumors that the polio vaccine caused sterilization in children and was part of a campaign by Western governments to depopulate Muslim countries. Although the rumors were quelled with help of health acre people from Indonesia, a Muslim country, immunizations were stopped for 11 months and that allowed polio to take hold in certain areas and from there travel around the globe.

Progress is being made in Nigeria. The government in northern Nigeria has stepped up their involvement. Now Somalia is a concern. Before 2005 not cases had been recorded since 2002. More than 150 cases were reported in 2005 and lawlessness in Somalia make reaching areas where the disease may be taking hold a big problem.


Smallpox is a disease caused by an airborne agent. It was one of the serious diseases before the 20th century. Highly contagious, it killed 30 percent of those who contacted it and usually inflicted terrible facial scars on those that survived. Over the centuries it ravaged Roman armies and nearly wiped out entire cities and towns.

Smallpox victims died a miserable and painful death. Early on victims had spots that could be mistaken for chicken pox. As times went on these develop into pustules that spread over the body, hardened and resemble infected bee stings. People that survived were left with terrible scars.

Smallpox is the only disease to have ever been eradicated. It was officially eradicated in 1980. The United States and Russia are the only places that have kept the smallpox virus. Vaccinations have stopped and people are vulnerable to it as they were in the past.

Smallpox was eradicated in 10 year campaign that lasted from 1967 to 1977. In the late 2000s there were reports of smallpox in eastern Uganda. A WHO investigation revealed that the disease was most likely chicken pox.

Smallpox Vaccination

In 1796, England's Edward Jenner administered the first safe smallpox vaccine on one of his servants. At the age of eight Jenner was one of 800 people who underwent a series of experiments developed by Lady Mary Wortley Montagu, a once beautiful noblewoman who survived but was badly scarred by smallpox in Turkey, where she was told by a Turkish doctor about the folk practice in his country in which healers scraped children with the fluid from smallpox blister to give them life-long immunity.

Montagu used the procedure on her children, who suffered no ill effects, and convinced the Princess of Wales to do the same with her daughters. The only problem with Montagu's experiment was that 10 percent of those who received the procedure caught smallpox and died.

As a grown man Jenner was obsessed with finding a cure for smallpox. While doing his medical apprenticeship, he was told a story about milkmaids who suffered from cow pox but were immune to smallpox. His first vaccine contained material from cow pox pustules collected from the milk maid's hands. The method was not as dangerous as Montagu’s smallpox procedure because the antibodies developed as protection against cow pox also stopped smallpox and cow pox was not as dangerous as smallpox.

Jenner's vaccine not only offered protection against smallpox it also was the beginning of a disease-fighting strategy that has been used to tackle a host of diseases. The word "vaccination" comes from the Latin word for "cow."

Jenner was also a passionate ornithologist and accomplished amateur musician. He could have made a fortune from his procedure if he kept it secret but he chose to promote its use around the world for free while others around him profited from it. Before he was awarded a grant by Parliament he was called "the most poverty-stricken great man in Europe."

Book: “Edward Jenner: The Cheltanham Years 1795-1823" by Paul Saunders (University Press of New England)

Image Sources:

Text Sources: Centers for Disease Control and Prevention (CDC), U.S. Department of Health and Human Services; World Health Organization (WHO) fact sheets; National Geographic, New York Times, Washington Post, Los Angeles Times, The New Yorker, Time, Reuters, Associated Press, AFP, Lonely Planet Guides and various websites books and other publications.

Last updated May 2022

This site contains copyrighted material the use of which has not always been authorized by the copyright owner. Such material is made available in an effort to advance understanding of country or topic discussed in the article. This constitutes 'fair use' of any such copyrighted material as provided for in section 107 of the US Copyright Law. In accordance with Title 17 U.S.C. Section 107, the material on this site is distributed without profit. If you wish to use copyrighted material from this site for purposes of your own that go beyond 'fair use', you must obtain permission from the copyright owner. If you are the copyright owner and would like this content removed from factsanddetails.com, please contact me.