Category Archives: Africa

Grandes Chroniques de France The Death of Saint Louis.

The Schistosoma in the Reliquary

The 800th anniversary of the birth of Saint Louis, King of France, in 2014 provided an opportunity to obtain a sample of his relics for “scientific identification”. With all relics the chain of custody and its backstory are critical for evaluation. Most of Louis’ relics held in the Basilica of Saint-Denis  were destroyed during the religious violence of  sixteenth century Paris. Fortunately the process of preserving and transferring Louis home to France from the site of death on crusade in Tunis, North Africa left bits of him in several locations.  Part of the preservation process used at the time removed his intestines and other internal organs to be embalmed separately while the remainder of the body was boiled to clean the bones to return to Paris. The bones were enshrined in Paris, while the heart and some viscera were enshrined at the abbey of Monreale near Palermo by his brother Charles, King of Sicily, who oversaw the preparation of the body and its transport back to France.

13th century Reliquary of Saint Louis, Basicilla of St. Dominic, Bologna Italy. (Source: Photo of Georges Jansoone, public domain on Wikipedia)

During a stop over at Bologna en route to Lyon and then Paris, some of his viscera were removed and interned in the Basilica of Saint Dominic. In 1297 Louis, who had died on 25 August 1270, was officially canonized as Saint Louis of France.  A portion of these visceral relics were given for the consecration of the cathedral of Turin in 1895, and these were transferred to the cathedral of Versailles in 1985. It is from this visceral relic that the 2 g specimen was obtained for scientific evaluation.

Microscopic Examination

The plan is to do a full “medical and forensic anthropological analysis” of the remains. The first result released by Phillipe Charlier’s team is the discovery of a semicircular parasite viewed by Scanning Electron Microscope (SEM) analysis, identified as a male Schistosoma based on its size and morphology.  Schistomsoma are a sexually dimorphic flat worm, also known as a blood fluke, that inhabit the capillaries of the abdomen (mesentery or bladder plexus depending on species) and release their eggs into either feces or urine. The eggs hatch in fresh water and must pass through a fresh water snail before emerging as larvae that can inhabit a mammalian host. Only about 50% of the eggs produced actually exit the body.  The adult worms and eggs that do not reach the feces or urine can cause extensive inflammation resulting in granulomas and fibrosis (scar tissue) to the abdominal organs (liver, spleen, intestines, bladder) and the blood vessels of the abdomen causing an accumulation of fluid in the peritoneal cavity.  Eggs that do breach into the lumen of the intestine cause chronic blood loss into the lumen producing chronic bloody stools. In the worst cases the blood loss can cause anemia.

Saint Louis
Source: Charlier, Bouchet, Weil & Bonnet, 2015.

Compare to a SEM preparation of a modern (non-mummified) male Schistosoma:

A C-shaped male schistosoma; the smaller female resides in the canal. (Source: David Williams, Illinois State University made public domain, Wikipedia)

King Louis had not been in Tunis long enough for him to contracted schistosomiasis upon his arrival only a month before his death. When and where he contracted the flat worm infestation is open to more speculation.  Schistosoma have been observed in archaeological remains of one individual from 9th century France, but have not yet been commonly observed. Charlier et al. (2015) suggest that Louis’ previous crusade in North Africa between 1250 and 1254, spending some time imprisoned in Damietta, Egypt, is the most likely period for start of the infection. If this is true, then Louis would have had a chronic infection for about 20 years at the time of his death. Charlier’s team do not believe that Schistosomiasis contributed to his death.

So far they have not observed any other parasites in the sample. This is not necessarily surprising considering that they have not yet identified the anatomic source of the specimen. It is not possible to even guess at the anatomic source from the crumbling, blackened specimen pictured in their study (fig. 1). Their analysis is continuing.

Debating Saint Louis’ Cause of Death

As soon as the schistosoma report was published, the debate on the cause of Louis’ death began in the letters of Forensic Science, Medicine and Pathology (where the report was published). So lets begin with the best account of Louis’ death, and go from there.

Beyond skirmishing and entrenching the camp nothing was done, as King Louis was awaiting the arrival of his brother Charles of Anjou (now King of Sicily). Whilst they were waiting encamped, John Tristan fell sick, and died on board one of the ships on August 3rd. A few days later the Legate also died and many other persons, some of fever, some of dysentery. Philip, the King’s eldest son, fell sick with fever; and the King was taken with dysentery (the complaint to which he nearly succumbed in his first Crusade) and died on August 25th. (Guillaume de Nangis account in the Memoirs of Lord Joinville, Book 4, Ch. 4)

Strangely, the plague has traditionally been claimed as Louis’ cause of death. This is completely unfounded since the Black Death will not bring epidemic Yersinia pestis back to the Mediterranean for another 77 years! There is nothing in the account above to suggest plague. This has rightly been dismissed as Louis’ cause of death.

Eric Faure wrote a letter arguing that malaria was a possible cause based on reports of Louis’ history of tertian fevers dating back to the 1242. Faure suggests that Louis went on his first crusade in thanksgiving for surviving “cerebral malaria with a coma” after a relapse in 1244. Cerebral malaria is usually caused by Plasmodium falciparum, which is not a chronic (relapse causing) infection. If Louis suffered relapses of malaria contracted in France then it was most likely Plasmodium vivax, which rarely causes cerebral malaria. Whether or not Louis had cerebral malaria in the 1240s, this doesn’t really inform of his his health in 1270.  Faure also notes that some of the men on Louis’ last crusade had intermittent fevers suggestive of malaria. Faure reaches too far suggesting that the dysentery was a symptom of malaria. Gastrointestinal symptoms are possible but rare in malaria and usually then in children. Philippe Charlier responded with a letter dismissing Faure’s suggestion to look for Plasmodium in the remains, because they would not have caused Louis’ death. Following the report in Lord Joinville’s memoir (quoted above), Charlier reports in his letter that his team is now looking for evidence of bacteria, viruses or amoeba in the embalmed “intestines” that are more likely to be the cause of the “dysenteric syndrome” reported in “Louis and his court”.

I will be watching for the final report, but the idea of a single enteric pathogen being the cause of death may not really represent reality. Based on Joinville’s memoir is appears that the “court” was suffering from a variety of camp diseases found in most medieval armies on prolonged campaigns. In such a situation, co-infection is highly likely particularly with chronic parasites. Indeed, Louis was probably not the only one in camp with schistosomiasis lingering from previous travels.  Although I doubt malaria caused Louis’ dysentery, it is quite possible he was suffering from chronic malaria and that it contributed to weakening his health, making him more susceptible to other pathogens. Indeed co-infection with Schistosoma and Plasmosdium could have made him quite anemic.  It would still be worth knowing if Louis had an active malaria infection, even if Shigella or another enteric pathogen was the primary cause of death.


Charlier, P., Bouchet, F., Weil, R., & Bonnet, B. (Oct. 2015). Schistosomiasis in the mummified viscera of Saint-Louis (1270 AD). Forensic Science, Medicine, and Pathology, 1–2.

Faure, E. (Dec. 2015). The infections of Saint-Louis: possible involvement of malaria.[Letter]  Forensic Science, Medicine, and Pathology, 1–1.

Charlier, P. (2016). Neither plague nor malaria, but dysentery as a cause of death for St. Louis. [Letter]  Forensic Science, Medicine, and Pathology, 1–1.

The Memoirs of Lord Joinvilletranslated by Ethel Wedgwood, E-text. University of Virginia library

Louis IV of France, Wikipedia.

WHO fact sheet: Schistosomiasis

Schistosoma, Wikipedia

Michael Walsh, Schistosomiasis on the Infection Landscapes blog. See this page for the best description of the medical effects of schistosomiasis.

A Synopsis of an Unusual Pneumonic Plague Outbreak in Madagascar, 2011

Plague appears in Madagascar every year, but it can still come as a surprise. It did in the January of 2011 when it appeared in an area of northern Madagascar that had never had an outbreak before. Not only was it a new area, but all of the cases were pneumonic. Not one case of bubonic plague. Eleven people were dead before antibiotics were given to the first patients on January 28. Vincent Richard and colleagues describe the outbreak in the forthcoming January issue of Emerging Infectious Diseases.

The index case was a thirteen year old boy who worked in a copper mine and developed a headache, fever and chills on a trip to his home village on January 6. He progressed to a fever, headache, a cough, severe chest pain and bloody sputum before dying at home on January 14. By January 22, his mother, her husband, daughter and granddaughter had died. Three other family members were showing symptoms of pneumonic plague when a neighboring family began to care for them beginning the second round of infections in twelve other people.  Visitors to the second household transmitted it to three more households. The last two fatal cases (19 & 20) were the brother who carried his sister to a traditional healer who was the last fatal case dying on February 9.

Plague transmission (Richard et al, 2015)
Plague transmission (Richard et al, 2015)

The epidemiological investigation identified 41 contacts: 17 from infected households and 25 who had more fleeting contact with a fatal case. None of these contacts had plague specific symptoms. All contacts were serum tested for plague with the Rapid Diagnostic Test (RDT, ‘the dipstick’) and all, but two who refused, were given prophylactic antibiotics. Details of how the contacts are connected are shown in the graphic above and narrated in the report by Richards et al in Emerging Infectious Diseases. Only two of these carriers were seropositive; one had a cough and refused antibiotics (c25) but did not progress. He is not considered a symptomatic case in the report. Three other contacts had mild pulmonary symptoms but were seronegative. They are not considered plague cases.  The wife of a fatal case cared for her husband and shared his bed until his death; she never turned seropositive.

Public health response followed the WHO protocols but was hampered by the outbreak being spread over seven villages 30 km from the index household in an area where plague had not been previously reported. This slowed the identification of contacts and dispensing antibiotics. Unfortunately postmortem specimens were not collected so there were only five specimens from symptomatic cases  to analyze. Initial sputum samples for three cases were positive for the Yersinia pestis F1 antigen by the RDT dipstick and all five specimens were transported about 900 km to the Institut Pasteur de Madagascar in Antananarivo to be analyzed. All attempts to culture Yersinia pestis from the specimens in bacterial media and mice failed.  Diagnoses were confirmed and titers quantitated by an ELISA based immunological detection for three cases. Cases were classified as suspected (17), presumptive (2) and confirmed (3) based on the WHO diagnostic criteria. The two presumptive cases were the seropositive non-symptomatic contacts. This highlights a problem with the WHO criteria since one seropositive case refused antibiotics and never developed plague specific symptoms. Presumptive should be a higher standard than suspected, which is based on clinical symptoms alone.

All cases that developed symptomatic pneumonic plague had the same symptoms: fever, chest pain, a cough, and bloody sputum. They were infectious for 48-72 hours after a 4-6 day latency period. This relatively long latency period allowed antibiotics to prevent the development of symptomatic plague in contacts. The effect of antibiotics on symptomatic patients was stark; five treated patients survived while all fifteen untreated patients died. With such a drastic difference between treated and untreated, the overall 75% case fatality rate is not really reflective of the virulence of the pathogen. Antibiotics alone determined the survival of symptomatic cases. Of the 36 people living in infected households, 20 developed symptomatic plague for an attack rate of 55% within the households; non-household contacts are excluded from the attack rate calculation.

Investigation of the presumptive focus is not begin until two months after the beginning of the plague response. Trapping of rodents in the area around the initial two villages,  Ambakirano and Ankatakata, produced 64 rodents and five dogs were sampled. Only one greater hedgehog (1 of 6) and two dogs were seropositive for Yersinia pestis by ELISA.  As wide ranging carnivores who are fairly resistant to plague, seroconversion in dogs is considered to be a good sentinel indicator. No fleas were collected; no dead rats were observed. All 51 black rats collected were seronegative, but Yersinia pestis DNA was isolated from the spleens of five rats. All strains fit the Malagasy specific 1.ORI3-k SNP pattern. There was enough minor variation in CRISPRs (a type of genetic fingerprinting information) to suggest a pre-existing enzootic focus is present. With such benign animal evidence, there is no reason to think that there was an epizootic that spilled over to humans. This is not surprising considering there were no bubonic cases. All of the human cases appear to be connected to the index case and to have passed human to human. Unfortunately, there is no mention of investigating a potential plague focus near the copper mine where the index case was working before symptoms appeared on his way to his home village.

While the survivors of the 2011 outbreak responded well to streptomycin, resistant strains were reported in the 2011 outbreak to Richards et al (2015) as personal communication. It is unclear if this means in an animal isolate from the region or another outbreak in 2011. Resistant strains have been reported in Madagascar since 1995 and are now apparently persistent.

This outbreak highlights how difficult it is to initially identify a pneumonic only outbreak. Spread by droplets, transmission can be broken by simple masks or, the Malagasy team suggests, even hygiene like turning away from others while coughing or covering the mouth and nose. People were able to care for and bury their dead without contracting disease.  On the other hand, antibiotics alone stopped the outbreak. Whether or not it would have ended on its own, we will never know. Although only two contacts were seropositive, prophylactic antibiotics likely prevented more infections.


Richard V, Riehm JM, Herindrainy P, Soanandrasana R, Ratsitoharina M, Rakotomanana F, et al. Pneumonic plague outbreak, northern Madagascar, 2011. Emerg Infect Dis [Internet]. 2015 Jan [ahead of print publication 5 Dec 2014].

See my previous post for more information on antibiotic resistant Yersinia pestis in Madagascar.

Ebola’s Chain of Infection

Chain of Infection A chain of infection is a method for organizing the basic information needed to respond to an epidemic.  I’ve gathered the best information I’ve been able to find. As the current epidemic is analyzed, there is no doubt some of the recommendations and basic knowledge will change.

The Ebola Virus (EBOV)

img8The Ebola virus is a Filovirus, an enveloped RNA virus containing only eight genes. Three of the five ebola virus species are highly pathogenic to humans: Zaire ebolavirus (Case fatality rate (CFR) 70-90%), Sudan ebolavirus (CFR ~50%) and Bundibugyo ebolavirus (CFR 25%). The 2014 epidemic is caused by the  Zaire ebolavirus.

Ebola attaches to the host cell via glycoproteins that trigger absorption of the virus. Once inside the cell it uncoats and begins replicating the eight negative sense RNA genes (seven structural genes and one non-structural gene). It initially targets immune cells that respond to the site of infection; monocytes/macrophages carry it to lymph nodes and then the liver and spleen. It then spreads throughout the body producing a cytotoxic effect in all infected cells. Death occurs an average of 6-16 days after the onset of symptoms from multi-organ failure and hypotensive shock.

Symptoms present 2-21 days after infection and the patient is contagious from the onset of symptoms.  Symptoms include a fever, fatigue, headache, nausea and vomiting, abdominal pain, diarrhea, coughing, focal hemorrhaging of the skin and mucus membranes, skin rashes and disseminated intravascular coagulation (DIC). In the 2014 epidemic, abnormal bleeding has only occurred in 18% of cases and late in the disease process.

The Reservoir

Fruit bats in Africa are believed to be the primary reservoir. Transmission between bats and other animals is poorly understood.


Portal of Exit

Ebola leaves its reservoir by contact with body fluids of an infected animal, often by bushmeat hunters. The spill-over is usually very small with the vast majority of human cases being caused by human to human transmission.


Transmission between humans occurs by contact of skin or mucus membranes with the body fluids of an infected person. Viral particles are found in all body fluids: blood, tears, saliva, sputum, breast milk,  diarrhea, vomit, urine, sweat and oil glands of the skin, and semen. Ebola can be found in semen three months after recovery from an infection but transmission by this route is poorly understood. Viral particles are found in other body fluids for 15 days or less after the onset of symptoms. It lasts the longest in convalescent semen and breast milk. All fluids from dead bodies are highly infectious.

All materials touched by the infected person, body fluids, medical waste, and used PPE must be discarded and destroyed as infectious medical waste. Non-disposable items like rubber boots, furniture, and building structures must be professionally decontaminated.

Ebola virus is a Biosafety Level 4 pathogen and a category A bioterrorism agent along with other viral hemorrhagic fevers.

Portal of Entry

Ebola enters the human body through breaks in the skin, including micro-abrasions and splashes on mucus membranes. Personal protective equipment (PPE) includes full body coverage including hood, mask or face shield, a tight fitting respirator, boots or shoe coverings, and double gloving. A buddy system should be used for dressing and disrobing. Removing PPE is a point of frequent contamination and should be done with help from another robed person.

Vulnerable populations

The most vulnerable populations for ebola are defined by their occupation. Care givers in medical facilities are at the highest risk because the viral titers reach the highest levels in fatal cases shortly before death. Mortuary and burial workers are also at high risk. The infectiousness of the bodies means that the usual burial practices can not be done in any setting or country. Home caregivers and decontamination workers would also be at a higher risk.

Information is lacking on survival vulnerabilities such as age, gender, pregnancy, or pre-existing conditions. More information on these aspects should be available in the post-epidemic analysis of the current epidemic.


References and further reading:

Martines, R. B., Ng, D. L., Greer, P. W., Rollin, P. E., & Zaki, S. R. (2014). Tissue and cellular tropism, pathology and pathogenesis of Ebola and Marburg Viruses. The Journal of Pathology, n/a–n/a. doi:10.1002/path.4456 [in press]

Chowell, G., & Nishiura, H. (2014). Transmission dynamics and control of Ebola virus disease (EVD): a review. BMC Medicine, 12(1), 196. doi:10.1186/s12916-014-0196-0

Toner, E., Adalja, A., & Inglesby, T. (2014). A Primer on Ebola for Clinicians. Disaster Medicine and Public Health Preparedness, 1–5. doi:10.1017/dmp.2014.115

Bausch, D. G., Towner, J. S., Dowell, S. F., Kaducu, F., Lukwiya, M., Sanchez, A., et al. (2007). Assessment of the Risk of Ebola Virus Transmission from Bodily Fluids and Fomites. Journal of Infectious Diseases, 196(s2), S142–S147. doi:10.1086/520545

CDC: Ebola Virus Disease portal