Ancient genomes reveal a high diversity of Mycobacterium leprae in medieval Europe.

Studying ancient DNA allows us to retrace the evolutionary history of human pathogens, such as Mycobacterium leprae, the main causative agent of leprosy. Leprosy is one of the oldest recorded and most stigmatizing diseases in human history. The disease was prevalent in Europe until the 16th century and is still endemic in many countries with over 200,000 new cases reported annually. Previous worldwide studies on modern and European medieval M. leprae genomes revealed that they cluster into several distinct branches of which two were present in medieval Northwestern Europe. In this study, we analyzed 10 new medieval M. leprae genomes including the so far oldest M. leprae genome from one of the earliest known cases of leprosy in the United Kingdom-a skeleton from the Great Chesterford cemetery with a calibrated age of 415-545 C.E. This dataset provides a genetic time transect of M. leprae diversity in Europe over the past 1500 years. We find M. leprae strains from four distinct branches to be present in the Early Medieval Period, and strains from three different branches were detected within a single cemetery from the High Medieval Period. Altogether these findings suggest a higher genetic diversity of M. leprae strains in medieval Europe at various time points than previously assumed. The resulting more complex picture of the past phylogeography of leprosy in Europe impacts current phylogeographical models of M. leprae dissemination. It suggests alternative models for the past spread of leprosy such as a wide spread prevalence of strains from different branches in Eurasia already in Antiquity or maybe even an origin in Western Eurasia. Furthermore, these results highlight how studying ancient M. leprae strains improves understanding the history of leprosy worldwide.

Tuberculosis and leprosy associated with historical human population movements in Europe and beyond - an overview based on mycobacterial ancient DNA.

Context: Tuberculosis and leprosy are readily recognised in human remains due to their typical palaeopathology. Both Mycobacterium tuberculosis (MTB) and Mycobacterium leprae (ML) are obligate pathogens and have been detected in ancient human populations. Objective: To demonstrate historical tuberculosis and leprosy cases in Europe and beyond using molecular methods, as human populations are associated with different mycobacterial genotypes. Methods: MTB and ML ancient DNA (aDNA) has been detected by DNA amplification using PCR, or by whole genome sequencing. Mycobacterial cell wall lipids also provide specific markers for identification. Results: In 18th century Hungary, the European indigenous MTB genotype 4 strains have been found. However, many individuals were co-infected with up to three MTB sub-genotypes. In 8th-14th century Europe significant differences in ML genotypes were found between northwest Europe compared with central, southern, or eastern Europe. In addition, several co-infections of MTB and ML were detected in historical samples. Conclusion: Both MTB and ML strain types differ between geographically separate populations. This is associated with ancient human migration after an evolutionary bottleneck and clonal expansion. The absence of indigenous leprosy in Europe today may be due to the greater mortality of tuberculosis in individuals who are co-infected with both organisms.

Ready Experimental Translocation of Mycobacterium canettii Yields Pulmonary Tuberculosis.

Mycobacterium canettii, which has a smooth colony morphology, is the tuberculous organism retaining the most genetic traits from the putative last common ancestor of the rough-morphology Mycobacterium tuberculosis complex. To explore whether M. canettii can infect individuals by the oral route, mice were fed phosphate-buffered saline or 106M. canettii mycobacteria and sacrificed over a 28-day experiment. While no M. canettii was detected in negative controls, M. canettii-infected mice yielded granuloma-like lesions for 4/4 lungs at days 14 and 28 postinoculation (p.i.) and positive PCR detection of M. canettii for 5/8 mesenteric lymph nodes at days 1 and 3 p.i. and 5/6 pooled stools collected from day 1 to day 28 p.i. Smooth M. canettii colonies grew from 68% of lungs and 36% of spleens and cervical lymph nodes but fewer than 20% of axillary lymph nodes, livers, brown fat samples, kidneys, or blood samples throughout the 28-day experiment. Ready translocation in mice after digestive tract challenge demonstrates the potential of ingested M. canettii organisms to relocate to distant organs and lungs. The demonstration of this relocation supports the possibility that populations may be infected by environmental M. canettii.

Leprosy in a Lombard-Avar cemetery in central Italy (Campochiaro, Molise, 6th-8th century AD): ancient DNA evidence and demography.

BACKGROUND: The study of past infectious diseases increases knowledge of the presence, impact and spread of pathogens within ancient populations. AIM: Polymerase chain reaction (PCR) was used to examine bones for the presence of Mycobacterium leprae ancient DNA (aDNA) as, even when leprosy is present, bony changes are not always pathognomonic of the disease. This study also examined the demographic profile of this population and compared it with two other populations to investigate any changes in mortality trends between different infectious diseases and between the pre-antibiotic and antibiotic eras. SUBJECTS AND METHODS: The individuals were from a site in Central Italy (6th-8th CE) and were examined for the presence of Mycobacterium leprae aDNA. In addition, an abridged life mortality table was constructed. RESULTS: Two individuals had typical leprosy palaeopathology, and one was positive for Mycobacterium leprae aDNA. However, the demographic profile shows a mortality curve similar to that of the standard, in contrast to a population that had been subjected to bubonic plague. CONCLUSIONS: This study shows that, in the historical population with leprosy, the risk factors for health seem to be constant and distributed across all age classes, similar to what is found today in the antibiotic era. There were no peaks of mortality equivalent to those found in fatal diseases such as the plague, probably due to the long clinical course of leprosy.

Insights from paleomicrobiology into the indigenous peoples of pre-colonial America - a review.

This review investigates ancient infectious diseases in the Americas dated to the pre-colonial period and considers what these findings can tell us about the history of the indigenous peoples of the Americas. It gives an overview, but focuses on four microbial pathogens from this period: Helicobacter pylori, Mycobacterium tuberculosis, Trypanosoma cruzi and Coccidioides immitis, which cause stomach ulceration and gastric cancer, tuberculosis, Chagas disease and valley fever, respectively. These pathogens were selected as H. pylori can give insight into ancient human migrations into the Americas, M. tuberculosis is associated with population density and urban development, T. cruzi can elucidate human living conditions and C. immitis can indicate agricultural development. A range of methods are used to diagnose infectious disease in ancient human remains, with DNA analysis by polymerase chain reaction one of the most reliable, provided strict precautions are taken against cross contamination. The review concludes with a brief summary of the changes that took place after European exploration and colonisation.

The two extremes of Hansen's disease-Different manifestations of leprosy and their biological consequences in an Avar Age (late 7th century CE) osteoarchaeological series of the Duna-Tisza Interfluve (Kiskundorozsma-Daruhalom-dulo II, Hungary).

To give an insight into the different manifestations of leprosy and their biological consequences in the Avar Age of the Hungarian Duna-Tisza Interfluve, two cases from the 7th-century-CE osteoarchaeological series of Kiskundorozsma-Daruhalom-dulo II (Hungary; n = 94) were investigated. Based on the macromorphology of the bony changes indicative of Hansen's disease, KD271 (a middle-aged male) and KD520 (a middle-aged female) represent the two extremes of leprosy. KD271 appears to have an advanced-stage, long-standing near-lepromatous or lepromatous form of the disease, affecting not only the rhinomaxillary region but also both upper and lower limbs. This has led to severe deformation and disfigurement of the involved anatomical areas of the skeleton, resulting in his inability to perform the basic activities of daily living, such as eating, drinking, grasping, standing or walking. The skeleton of KD520 shows no rhinomaxillary lesions and indicates the other extreme of leprosy, a near-tuberculoid or tuberculoid form of the disease. As in KD271, Hansen's disease has resulted in disfigurement and disability of both of the lower limbs of KD520; and thus, the middle-aged female would have experienced difficulties in standing, walking, and conducting occupational physical activities. KD271 and KD520 are amongst the very few published cases with leprosy from the Avar Age of the Hungarian Duna-Tisza Interfluve, and the only examples with detailed macromorphological description and differential diagnoses of the observed leprous bony changes. The cases of these two severely disabled individuals, especially of KD271 -who would have required regular and substantial care from others to survive-imply that in the Avar Age community of Kiskundorozsma-Daruhalom-dulo II there was a willingness to care for people in need.

Verification of tuberculosis infection among Vác mummies (18th century CE, Hungary) based on lipid biomarker profiling with a new HPLC-HESI-MS approach.

Tuberculosis (TB) was a large burden of infections that peaked during the 19th century in Europe. Mummies from the 18th century CE, discovered in the crypt of a church at Vác, Hungary, had high TB prevalence, as revealed by amplification of key fragments of TB DNA and genome-wide TB analysis. Complementary methods are needed to confirm these diagnoses and one approach uses the identification of specific lipid biomarkers, such as TB mycocerosic acids (MCs). Previously, MC derivatives were profiled by specialised gas chromatography-mass spectrometry (GC-MS), so an alternative more direct approach has been developed. Underivatized MCs are extracted and analysed by high-performance liquid chromatography linked to a mass spectrometer, in heated electrospray ionisation mode (HPLC-HESI-MS). The method was validated using representatives of the Mycobacterium tuberculosis complex and other mycobacteria and tested on six Vác mummy cases, previously considered positive for TB infection. Analysing both rib and soft tissue samples, four out of six cases gave profiles of main C32 and major C29 and C39 mycocerosates correlating well with those of M. tuberculosis. Multidisciplinary methods are needed in the diagnosis of ancient tuberculosis; this new protocol accesses important confirmatory evidence, as demonstrated by the confirmation of TB in the Vác mummies.

Tuberculosis in Dr Granville's mummy: a molecular re-examination of the earliest known Egyptian mummy to be scientifically examined and given a medical diagnosis.

'Dr Granville's mummy' was described to the Royal Society of London in 1825 and was the first ancient Egyptian mummy to be subjected to a scientific autopsy. The remains are those of a woman, Irtyersenu, aged about 50, from the necropolis of Thebes and dated to about 600 BC. Augustus Bozzi Granville (1783-1872), an eminent physician and obstetrician, described many organs still in situ and attributed the cause of death to a tumour of the ovary. However, subsequent histological investigations indicate that the tumour is a benign cystadenoma. Histology of the lungs demonstrated a potentially fatal pulmonary exudate and earlier studies attempted to associate this with particular disease conditions. Palaeopathology and ancient DNA analyses show that tuberculosis was widespread in ancient Egypt, so a systematic search for tuberculosis was made, using specific DNA and lipid biomarker analyses. Clear evidence for Mycobacterium tuberculosis complex DNA was obtained in lung tissue and gall bladder samples, based on nested PCR of the IS6110 locus. Lung and femurs were positive for specific M. tuberculosis complex cell-wall mycolic acids, demonstrated by high-performance liquid chromatography of pyrenebutyric acid-pentafluorobenzyl mycolates. Therefore, tuberculosis is likely to have been the major cause of death of Irtyersenu.

Oldest evidence of tuberculosis in Argentina: A multidisciplinary investigation in an adult male skeleton from Saujil, Tinogasta, Catamarca (905-1030 CE).

The Mycobacterium tuberculosis complex (MTC) has affected South American populations since ca. 200 years BCE. In Argentina, possible cases date from ca. 1000-1400 Common Era (CE). This paper describes the oldest (905-1030 CE) confirmed case of tuberculosis (TB) in a young adult male from Lomitas de Saujil (Tinogasta, Catamarca, Argentina). Osteolytic lesions on the bodies of the lower spine were macroscopically and radiographically identified. Bilateral new bone formation was seen on the visceral vertebral third of several ribs and in long bones, compatible with hypertrophic osteoarthropathy. Representative rib and hand bones gave profiles for MTC-specific C27-C32 mycocerosic acid lipid biomarkers; these were strongest in one heavily-lesioned lower rib, which also had MTC-diagnostic C76-C89 mycolic acids and positive amplification of MTC-typical IS6110 aDNA fragments. During the first millennium CE, the intense social interaction, the spatial circumscription of villages among the pre-Hispanic societies in the mesothermal valleys of Catamarca and the fluid contacts with the Eastern lowlands, valleys and puna, were factors likely to favor disease transmission. It is proposed that TB arrived from northern Chile and dispersed towards the northeast into the Yocavil valley, where several cases of TB infection were macroscopically identified for a later chronology.

Intestinal tuberculosis.

PURPOSE OF REVIEW: Intestinal tuberculosis (TB) is increasing due partly to the HIV pandemic. Its clinical presentation mimics inflammatory conditions such as Crohn's disease and malignancies, which are becoming more prevalent, so the diagnosis is problematic. RECENT FINDINGS: Greater awareness of intestinal TB is needed, both in countries where TB is endemic and developed countries with immigrant populations. Some strains of Mycobacterium tuberculosis are associated with more extrapulmonary disease and greater dissemination, thereby exacerbating the rise in HIV-associated extrathoracic TB. Recent retrospective and prospective studies are leading to the development of diagnostic algorithms. A wide range of imaging techniques is available for sampling and diagnosis. New biochemical, immunological and molecular diagnostic methods are being developed but must be standardized and validated. Developments in drug delivery will facilitate oral therapy even in patients suffering from malabsorption. SUMMARY: There is an increasing consensus on the risk factors and clinical presentations of intestinal TB. Imaging techniques, coupled with fine needle biopsies, are useful aids to diagnosis, but most important is a greater awareness of the condition by clinicians.

Osteoarcheological and biomolecular evidence of leprosy from an 11-13th century CE Muslim cemetery in Europe (Orosháza, Southeast Hungary).

Orosháza site no. 10 (Southeast Hungary) contains the partially excavated archaeological remains of an 11-13th century CE Muslim merchant village and its cemetery located in close proximity to Christian villages of the same era. The skeleton of a young woman (grave no. 16) from the last phase of the cemetery use was identified with rhinomaxillary lesions associated with lepromatous leprosy. The right parietal bone also exhibited signs of cranial trauma, possibly caused by symbolic trepanation, a well-known ritual practice in the 9-11th century CE Carpathian Basin. The retrospective diagnosis of the disease was supported by ancient DNA analysis, as the samples were positive for Mycobacterium leprae aDNA, shown to be of genotype 3. Contrary to the general practice of the era, the body of the young female with severe signs of leprosy was interred among the regular graves of the Muslim cemetery in Orosháza, which may reflect the unique cultural background of the community.

In situ PCR for Mycobacterium tuberculosis in endoscopic mucosal biopsy specimens of intestinal tuberculosis and Crohn disease.

Tuberculosis and Crohn disease are granulomatous disorders affecting the intestinal tract with similar clinical manifestations and pathologic features. We evaluated the use of in situ polymerase chain reaction (PCR) using Mycobacterium tuberculosis complex-specific primers for IS 6110 to differentiate these 2 disorders in archival mucosal biopsy specimens. In situ PCR was positive in 6 of 20 tuberculosis biopsy specimens and 1 of 20 Crohn disease biopsy specimens. Staining was localized to a site of granulomatous inflammation in 3 of the tuberculosis specimens and in the Crohn disease specimen. In the other tuberculosis biopsy specimens, positive staining was localized to inflammatory granulation tissue and to a focus of intact mucosa without granulomatous inflammation. The presence of M tuberculosis DNA in Crohn disease could be due to coexisting latent tuberculosis or indicate a role for these bacteria in triggering an abnormal immune response. Therefore, in situ PCR is potentially useful to differentiate intestinal tuberculosis from Crohn disease, if the sensitivity is improved.

Insights gained from ancient biomolecules into past and present tuberculosis-a personal perspective.

Ancient and historical tuberculosis (TB) can be recognized by its typical paleopathology in human remains. Using paleomicrobiology, it is possible to detect many more individuals infected with TB but with no visible lesions. Due to advances in molecular analysis over the past two decades, it is clear that TB was widespread in humans from the Neolithic period and has remained so until the present day. Past human populations were associated with different lineages of the Mycobacterium tuberculosis complex, thereby elucidating early human migrations. Using paleomicrobiology, it is possible to detect individuals infected with TB who are also co-infected with other bacteria or parasites. TB is also found in hosts with co-morbidities such as neoplasms, or metabolic disorders such as rickets and scurvy. In well-preserved human skeletal or mummified tissue, whole genome sequencing has detected individuals with multiple infections of different M. tuberculosis strains. Such studies put modern findings into context and emphasize the importance of human population density in such circumstances.

Possible cases of leprosy from the Late Copper Age (3780-3650 cal BC) in Hungary.

At the Abony-Turjányos dulo site, located in Central Hungary, a rescue excavation was carried out. More than 400 features were excavated and dated to the Protoboleráz horizon, at the beginning of the Late Copper Age in the Carpathian Basin, between 3780-3650 cal BC. Besides the domestic and economic units, there were two special areas, with nine-nine pits that differed from the other archaeological features of the site. In the northern pit group seven pits contained human remains belonging to 48 individuals. Some of them were buried carefully, while others were thrown into the pits. The aim of this study is to present the results of the paleopathological and molecular analysis of human remains from this Late Copper Age site. The ratio of neonates to adults was high, 33.3%. Examination of the skeletons revealed a large number of pathological cases, enabling reconstruction of the health profile of the buried individuals. Based on the appearance and frequency of healed ante- and peri mortem trauma, inter-personal (intra-group) violence was characteristic in the Abony Late Copper Age population. However other traces of paleopathology were observed on the bones that appear not to have been caused by warfare or inter-group violence. The remains of one individual demonstrated a rare set of bone lesions that indicate the possible presence of leprosy (Hansen's disease). The most characteristic lesions occurred on the bones of the face, including erosion of the nasal aperture, atrophy of the anterior nasal spine, inflammation of the nasal bone and porosity on both the maxilla and the bones of the lower legs. In a further four cases, leprosy infection is suspected but other infections cannot be excluded. The morphologically diagnosed possible leprosy case significantly modifies our knowledge about the timescale and geographic spread of this specific infectious disease. However, it is not possible to determine the potential connections between the cases of possible leprosy and the special burial circumstances.

Leprosy Associated with Atypical Cutaneous Leishmaniasis in Nicaragua and Honduras.

In Central America, few cases of leprosy have been reported, but the disease may be unrecognized. Diagnosis is based on clinical criteria and histology. Preliminary field work in Nicaragua and Honduras found patients, including many children, with skin lesions clinically suggestive of atypical cutaneous leishmaniasis or indeterminate leprosy. Histology could not distinguish these diseases although acid-fast organisms were visible in a few biopsies. Lesions healed after standard antimicrobial therapy for leprosy. In the present study, patients, family members, and other community members were skin-tested and provided nasal swabs and blood samples. Biopsies were taken from a subgroup of patients with clinical signs of infection. Two laboratories analyzed samples, using local in-house techniques. Mycobacterium leprae, Leishmania spp. and Leishmania infantum were detected using polymerase chain reactions. Mycobacterium leprae DNA was detected in blood samples and nasal swabs, including some cases where leprosy was not clinically suspected. Leishmania spp. were also detected in blood and nasal swabs. Most biopsies contained Leishmania DNA and coinfection of Leishmania spp. with M. leprae occurred in 33% of cases. Mycobacterium leprae DNA was also detected and sequenced from Nicaraguan and Honduran environmental samples. In conclusion, leprosy and leishmaniasis are present in both regions, and leprosy appears to be widespread. The nature of any relationship between these two pathogens and the epidemiology of these infections need to be elucidated.

Paleomicrobiology of Human Tuberculosis.

Tuberculosis is a significant global disease today, so understanding its origins and history is important. It is primarily a lung infection and is transmitted by infectious aerosols from person to person, so a high population density encourages its spread. The causative organism is Mycobacterium tuberculosis, an obligate pathogen in the M. tuberculosis complex that also contains closely related species, such as Mycobacterium bovis, that primarily infect animals. Typical bone lesions occur in about 5% of untreated infections. These can be recognized in historical and archaeological material, along with nonspecific paleopathology such as new bone formation (periostitis), especially on ribs. Based on such lesions, tuberculosis has been found in ancient Egypt, pre-Columbian America, and Neolithic Europe. The detection of M. tuberculosis ancient DNA (aDNA) by using PCR led to the development of the new field of paleomicrobiology. As a result, a large number of tuberculosis cases were recognized in mummified tissue and bones with nonspecific or no lesions. In parallel with these developments, M. tuberculosis cell wall lipid biomarkers have detected tuberculosis suggested by paleopathology and confirmed aDNA findings. In well-preserved cases, molecular typing has identified M. tuberculosis lineages and genotypes. The current interest in targeted enrichment, shotgun sequencing, and metagenomic analysis reveals ancient mixed infections with different M. tuberculosis strains and other pathogens. Identification of M. tuberculosis lineages from samples of known age enables the date of the emergence of strains and lineages to be calculated directly rather than by making assumptions on the rate of evolutionary change.

Co-infection of Mycobacterium tuberculosis and Mycobacterium leprae in human archaeological samples: a possible explanation for the historical decline of leprosy.

Both leprosy and tuberculosis were prevalent in Europe during the first millennium but thereafter leprosy declined. It is not known why this occurred, but one suggestion is that cross-immunity protected tuberculosis patients from leprosy. To investigate any relationship between the two diseases, selected archaeological samples, dating from the Roman period to the thirteenth century, were examined for both Mycobacterium leprae and Mycobacterium tuberculosis DNA, using PCR. The work was carried out and verified in geographically separate and independent laboratories. Several specimens with palaeopathological signs of leprosy were found to contain DNA from both pathogens, indicating that these diseases coexisted in the past. We suggest that the immunological changes found in multi-bacillary leprosy, in association with the socio-economic impact on those suffering from the disease, led to increased mortality from tuberculosis and therefore to the historical decline in leprosy.

Ancient DNA analysis - An established technique in charting the evolution of tuberculosis and leprosy.

Many tuberculosis and leprosy infections are latent or paucibacillary, suggesting a long time-scale for host and pathogen co-existence. Palaeopathology enables recognition of archaeological cases and PCR detects pathogen ancient DNA (aDNA). Mycobacterium tuberculosis and Mycobacterium leprae cell wall lipids are more stable than aDNA and restrict permeability, thereby possibly aiding long-term persistence of pathogen aDNA. Amplification of aDNA, using specific PCR primers designed for short fragments and linked to fluorescent probes, gives good results, especially when designed to target multi-copy loci. Such studies have confirmed tuberculosis and leprosy, including co-infections. Many tuberculosis cases have non-specific or no visible skeletal pathology, consistent with the natural history of this disease. M. tuberculosis and M. leprae are obligate parasites, closely associated with their human host following recent clonal distribution. Therefore genotyping based on single nucleotide polymorphisms (SNPs) can indicate their origins, spread and phylogeny. Knowledge of extant genetic lineages at particular times in past human populations can be obtained from well-preserved specimens where molecular typing is possible, using deletion analysis, microsatellite analysis and whole genome sequencing. Such studies have identified non-bovine tuberculosis from a Pleistocene bison from 17,500 years BP, human tuberculosis from 9000 years ago and leprosy from over 2000 years ago.

Evolutionary changes in the genome of Mycobacterium tuberculosis and the human genome from 9000 years BP until modern times.

The demonstration of Mycobacterium tuberculosis DNA in ancient skeletons gives researchers an insight into its evolution. Findings of the last two decades sketched the biological relationships between the various species of tubercle bacilli, the time scale involved, their possible origin and dispersal. This paper includes the available evidence and on-going research. In the submerged Eastern Mediterranean Neolithic village of Atlit Yam (9000 BP), a human lineage of M. tuberculosis, defined by the TbD1 deletion in its genome, was demonstrated. An infected infant at the site provides an example of active tuberculosis in a human with a naïve immune system. Over 4000 years later tuberculosis was found in Jericho. Urbanization increases population density encouraging M. tuberculosis/human co-evolution. As susceptible humans die of tuberculosis, survivors develop genetic resistance to disease. Thus in 18th century Hungarian mummies from Vác, 65% were positive for tuberculosis yet a 95-year-old woman had clearly survived a childhood Ghon lesion. Whole genome studies are in progress, to detect changes over the millennia both in bacterial virulence and also host susceptibility/resistance genes that determine the NRAMP protein and Killer Cell Immunoglobulin-like Receptors (KIRs). This paper surveys present evidence and includes initial findings.