~ Retrospective Identification

~1972

In the month of May in 1972, a doctor that worked at Tandala Hospital was performing an autopsy on a Zairois bible school student who had died of a sudden onset of a hemorrhagic illness (diagnosed as yellow fever). The physician, during the autopsy, accidentally cut his finger. He began feeling ill twelve days after he had received the laceration on his finger.

In February 1977, serum from medical personnel, who may have come in contact with Ebola, were tested for Ebola antibodies. The serum from this same physician tested positive. His hospital records were reviewed, and his symptoms were similar to that of Ebola Hemorrhagic Fever.

~Yambuku, Zaire in Africa

~1976

On August 28, 1976, a 44 year-old male (the index case), who worked at the Mission School, returned from a tour of northern Zaire. He began suffering from a feverish illness, which he believed was malaria. He had no idea he was suffering from Ebola Hemorrhagic Fever. On September 1, 1976, the man went to Yambuku Mission Hospital, to seek medical assistance for his sickness. He was given a parenteral injection of chloroquine (a drug used to fight off malaria). Unfortunately, this Yambuku hospital didn't follow proper safety precautions by reusing needles without sterilization. Also, the hospital mostly used parenteral injections for administering most medications. Therefore, Ebola-Zaire quickly spread throughout the villages serviced by the Yambuku Mission Hospital. September 30, 1976, the hospital shut down, after 11 of the 17 staff members contracted Ebola Hemorrhagic Fever. October 18th, The WHO International Commission was formed, and teams were mobilized October 30th. The last Ebola-Zaire case became terminal, on November 5, 1976. This was the end of the outbreak. · 1977. Tandala, Zaire.

~Tandala, Zaire

~1977

The case was a 9 year-old girl, who lived with her family in a tiny village called Bonduni, which was located 12.4 miles (20 km) from the mission. The child was in good health, and hadn't traveled outside of the Bonduni area. Suddenly, in the month of June, she had an onset of fever, abdominal pain, and hematemesis (the vomiting of blood). Three days later, she was admitted to Tandala Mission Hospital. When she was admitted to the hospital, she had a 103.1°F (39.5°C) body temperature (normal body temperature is 98.6°F (37°C) ). After physical examination, she had a clinical diagnosis of hemorrhagic fever. She later lost consciousness. Twenty-eight hours after admission to the Tandala Mission Hospital, the poor child was pronounced dead. However, none of her family members contracted the Ebola virus. An outbreak did not occur.

~ Minkébé and Makokou, Gabon in Africa

~1994

First Wave, December 1994

All of the cases were from three gold-panning encampments: Andock, Mékouka, and Minkébé. They were located in small forest clearings (2000-3000 square meters), which bordered the rain forest. This region of Gabon has a small population; a total of 350 people lived in the three villages. There was twenty in Andock, thirty in Mékouka, and 300 in Minkébé. A total of thirty-two people from the forest encampments contracted Ebola Hemorrhagic Fever (four from Andock, twenty-three from Mékouka, and five from Minkébé). The ill inhabitants traveled 62 miles (100 km) south, using a boat, to the Makokou General Hospital for medical treatment.

Second Wave, End of December 1994 to February 1995

The patients that were apart of the "second wave" were secondary or tertiary cases from the first wave, and these patients did not originate from the encampments. The "second wave" started at the end of the month of December of 1994. The first case was from Mayela, a small village near Makokou, which was far from the encampments of the "first wave". This person lived near a traditional healer, known as a "nganga," and was probably infected from contact with a hospitalized patient who went to the healer. By mid January, sixteen additional cases occurred near the road that ran south towards Fanceville (twelve more cases from Mayela, two cases from Ekobakoba, one case from Ekatiabe, and one case at Makokou General Hospital). None of these sixteen patients had been near the area affected by the "first wave" of the epidemic in Gabon (the three gold-panning encampments) during the previous three months. All the patients had either been in direct contact with ill relatives (people hospitalized at Makokou General Hospital or staying at a nganga's home), or came in contact with people caring for the patients. On February 9, 1995, the last case was from Ekobakoba, who was infected with Ebola while visiting a sick relative at Makokou General Hospital. Then, on February 17, 1995, the Gabonese health officials declared the epidemic officially over, only eight days after the last case. This left time for additional infections to occur. In previous Ebola outbreaks, an outbreak was not declared over until a period of forty-two days (twice the longest incubation period) had passed since the last known infection.

Result of both waves:

Overall, 49 people were admitted to Makokou General Hospital with suspected HF between December 1994 and February 1995. Twenty-nine of the 49 cases of Ebola Hemorrhagic Fever were fatal (fatality rate: 59%). Twenty-six of the EHF patients were male and 23 were female. The average age of the patients was 37. Whether the number of infected people reflects the true number of Ebola Zaire cases during this epidemic is unknown. Some of the patients with suspected Ebola fever could have had a different type of hemorrhagic fever, or a different disease all together. Some people who did have Ebola could have sought a nganga, without going to a hospital for care. Also, they could have died in their village, or in the rain forest without the investigative team's knowledge. Also, the exact origin of the virus during this epidemic is unknown. During this outbreak, there was more than one point of contact with Ebola. This led to a longer duration of the epidemic than if there was only one point of contact with Ebola (as in the Spring 1996 outbreak; see below).

~Kikwit, Zaire

~1995

The first case-patient of this outbreak was "GM", a 42-year-old male charcoal worker, a Seventh-Day Adventist. Prior to his illness, he had not eaten monkey meat, or was in contact with another Ebola patient (which usually transmits Ebola). However, his charcoal plot was on the edge a dense forest, and was, in fact, under a dense canopy of the forest. While working on his charcoal plot, he was probably exposed to a wide variety of possible vectors, or even the natural reservoir of the Ebola virus. On January 6, 1995, he was admitted to Kikwit General Hospital. He directly, and fatally, infected at least three members of his family, and ten members of his extended family. An area encompassing Kikwit, and three surrounding villages, were also infected, in a period of nine weeks. Some of the infected people from his family, and secondary and tertiary cases of other families (who provided nursing care or had been apart of the burial rituals of GM's family) went to Kikwit II Maternity Hospital.

On April 9, a 36 year-old male laboratory technician, who worked at Kikwit II Maternity Hospital, went to the Kikwit General Hospital, in Zaire, due to an onset of fever and bloody diarrhea. Suspecting a perforated bowel due to typhoid fever, he underwent surgery on April 10 and 11. However, he died April 13, four days after the onset of symptoms. On April 14, the medical personnel (who had cared for the laboratory worker in the operating room, or hospital wards) became ill with back, joint, and muscle aches, extreme asthenia (clinical term for physical weakness), headache, fever, and, in some cases, hemorrhagic manifestations. Over 70% of the first generation cases were on the hospital staff. One of the ill members of the staff was transferred to a hospital in Mosango, which was 75 miles (121 km) west of Kikwit. Some of the people who provided medical care for this individual developed similar symptoms on April 20 (approximately). Ten days after the first-generation cases, a second generation of cases occurred among the family and friends of the first-generation cases. During this outbreak, the virus was transmitted mainly person-to-person through contact with bodily fluids and ritual cleansing of corpses before burial (usually performed by women). The government of Zaire closed all schools in Kikwit, in order to limit the spread of the outbreak. However, the Kinshasa airport remained open during most of the outbreak. (Kikwit is located about 240 miles (386 km) east of Kinshasa.

The unusual nature of the laboratory technician's death, and the condition of the medical personnel who cared for him, prompted a local ad hoc committee to meet to discuss the cause of these deaths. J.J. Muyembe-Tamfun, Ministry of Health, Zaire, who had participated in the follow-up of the 1976 outbreak of Ebola-Zaire, suggested that these illnesses may be caused by a viral hemorrhagic fever. Specimens were obtained for analysis, and on May 4th, they were sent to the Institute of Tropical Medicine, Antwerp, Belgium. On May 6, 1995, based on the preliminary findings of the Institute for Tropical Medicine, the Zairian government sought the assistance of the Center for Disease Control with an outbreak of a viral hemorrhagic fever-like illness that was erupting in Kikwit, Zaire. On May 9th, the CDC received portions of these samples for diagnostic analysis. The CDC confirmed Ebola as the agent responsible for the disease in all fourteen patients (the index patient and the medical personnel who subsequently contracted it from him).

Four separate hospitals were involved in the outbreak. The first hospital (the center of the outbreak) was Kikwit General Hospital (the hospital that treated the laboratory technician). The second was Kikwit II Maternity Hospital, and the third was the hospital in Mosango, where one of the members of the medical staff who cared for the laboratory technician was transferred. The fourth hospital was in Yassa Bonga, approximately 155 miles (250 km.) from Kikwit.

The last identified case of Ebola Hemorrhagic Fever during this outbreak was a 27-year-old housewife from Nzinda, Kikwit. She was admitted to Kikwit II Maternity Hospital on June 24,1995, for the management of a septic abortion. She was discharged on July 14 and died in her home on July 16. August 24, 1995, the 1995 outbreak was declared over, twice the maximum known incubation period (which is 42 days) lapsed without any new cases of Ebola-Zaire.

(Over 1,400 samples of various fauna were collected for reservoir testing.)

Overall, 149 cases were male and 166 were female. 121 male cases were fatal (81% fatal) and 123 female cases were fatal (74% fatal). The ages of the cases ranged from three days to 71 years, with an average age of 35 years. Twenty-six of the Ebola Hemorrhagic Fever cases were less than 17 years old, and thirteen were over 60. The median age of the survivors was 29 years; median age of the fatal cases was 35 years. Of the 286 cases (where the professional occupations were known), 90 (32%) were health care workers and 61 (21%) were housewives (usually nursed the sick or performed the ritual cleansing and burial preparation for dead family members). Approximately 73% of the first 70 patients in the epidemic were medical workers, and the fatality rate among them was high.

266 of the Ebola cases were reported to have lived in Kikwit North and South Zones de Sante, the remaining in Mosango (23), the Zones de Sante of Bulungu (13 cases), Vanga (6), Gungu (4), Idiofa (1), Mokala (1), and Feshi (1). All of the cases were in the Kikwit and Kwilu administrative Sub-Regions, except for 1 case in the Kwango Sub-Region, Bandundu Region.

To see a graph of the deaths, click here.

~Mayibout, Gabon

~1996

On January 24, two men butchered a chimpanzee they found dead in the forest. On February 5 and 6, nineteen original cases showed signs of Ebola Hemorrhagic Fever (high fever, bloody diarrhea, and severely reddened eyes), were admitted to Makokou provincial hospital. Quick identification and the implementation of appropriate control measures brought the outbreak rapidly under control and further amplification was prevented. The last case died on March 12, 1996. The outbreak was officially declared over by the WHO (World Health Organization) on April 23, 1996; 42 days (twice the incubation period) after the last patient death. A total of 17 females and 20 males were infected, and the average age of the patients was 27 years (range of ages was seven months to 70 years).

~Booué, Gabon (and transported to Johannesburg, South Africa)

~1996

Outbreak in Booué

First case occurred on July 23, 1996 in Booué; a 39-year-old hunter who lived in a forest camp. He died on August 7. The second case was a close friend of the index case and died sometime in August. The third and the fourth cases of Ebola Hemorrhagic Fever (EHF) occurred in late September and were a traditional healer and his assistant (both cases were fatal). During the beginning of this outbreak, a dead chimpanzee was found in the forest. When tested for Ebola, the results were positive. On October 18, three of four new cases were in children who had been in close contact with previous cases. Some of those infected were transported to Libreville for treatment. The outbreak was brought under control by the international team by November 13, 1996, and the last patient died on January 18, 1997. World Health Organization declared the outbreak over March 2, 1997.

(Bernard Massika, with wife and ill child)

Out of the sixty cases, 44 were from the Booué area (33 fatal), 14 from Libreville (10 fatal), and one fatal case from Lambarene. There was no documented secondary transmission.

Transport from Libreville to Johannesburg

On October 27, a 40 year-old male Gabonese doctor, who was infected with Ebola in Libreville from a patient (who died November 5, 1996) who was linked to the Booué outbreak, flew to Johannesburg, South Africa to be treated. The doctor worked as a "resuscitator" at the 300 bed hospital in Libreville. On October 19, he developed a fever-like illness, which he treated with anti malarial drugs. A few days later, he developed a high fever and diarrhea. He was not aware that any of the patients he had treated had carried the Ebola virus. The physician was flew on a commercial plane to South Africa, accompanied by a nurse. He arrived to Morningside Medi Clinic with a diagnosis of rhabdomyolysis (a clinical and biochemical syndrome resulting from an injury which damages skeletal muscle, leading to the release of potentially toxic muscle cell components into the circulation). He had temperatures of 107.6°F (42°C) and was very ill. He also had signs of hepatitis. During his treatment, a muscle biopsy was performed (to test for rhabdomyolysis). It was later discover he was suffering from Ebola Hemorrhagic Fever. However, he recovered from EHF, and on November 20, 1996, he returned home to Gabon.

Mrs. Marilyn Lahana, a 46-year-old theater/anesthesia nursing sister, treated the Gabonese physician at Morningside Clinic, Johannesburg and became infected with the Ebola virus he carried. She was exposed to his blood when she performed a procedure for placing a central line on him. She was also exposed to a great deal of blood cleaning up after the procedure. November 2nd she became ill with a small fever. She began to have a severe headache on November 6 and was admitted to Sandton Medi Clinic with suspected encephalitis (inflammation of the brain). Doctors discovered she had a moderately low platelet count (105x10E9/L). Believing she had a bacterial infection, doctors placed her on antibiotics. Over the next few days in the hospital, she developed a skin rash and diarrhea, which the medical personnel believed to be a possible reaction to the antibiotics. By the 9th, her platelet count fell from 105 to 37; suspecting viral hemorrhagic fever (due to low platelets, rash, and fever), her blood was submitted for analysis. November 14, her blood tested positive for Ebola. Mrs. Lahana had developed hematemesis (bloody vomit), her liver was malfunctioning, and had slightly elevated white blood cell counts by November 14. On November 16, she was moved to Johannesburg Hospital, where strict barrier-nursing care was implemented. She died on November 24 from a brain hemorrhage.

*Due to the fact that these outbreaks occurred before Zaire was changed to the Democratic Republic of the Congo, the country that is currently known as the Democratic Republic of the Congo is referred to as Zaire on these Ebola pages.