Category Archives: Malaria

Summer reading


summer 2

The summer is officially over this week so its time for my quarterly reading update. I read a more eclectic mix of topics this summer than usual. These are just those that really stood out as being useful for my purposes. I hope you find something of interest!


  • Gregory Aldrete. Floods of the Tiber in Ancient Rome. 2006.
  • Robert Sallares, Malaria and Rome: A History of Malaria in Ancient Italy, 2002
  • Nukhet Varlik. Plague and Empire in the Early Modern Mediterranean: The Ottoman Experience 1347-1600. Cambridge UP, 2015
MA Thesis

Katharine Dean. Modeling plague transmission in Medieval European cities. (2015, June 1). MA Thesis.  Oslo.


  • Kimura, H., Saitoh, M., Kobayashi, M., Ishii, H., Saraya, T., Kurai, D., et al. (2015). Molecular evolution of haemagglutinin (H) gene in measles virus. Scientific Reports, 1–10. doi:10.1038/srep11648
  • Scheidel, W. (2015). Death and the City: Ancient Rome and Beyond. Available at SSRN 2609651.
  • Smith-Guzmán, N. E. (2015). The skeletal manifestation of malaria: An epidemiological approach using documented skeletal collections. American Journal of Physical Anthropology, n/a–n/a.
  • Sigl, M., Winstrup, M., McConnell, J. R., Welten, K. C., Plunkett, G., Ludlow, F., et al. (2015). Timing and climate forcing of volcanic eruptions for the past 2,500 years. Nature.

  • Kostick, C., & Ludlow, F. (2015). The dating of volcanic events and their impact upon European society, 400-800 CE (Vol. 5, pp. 7–30). Post-Classical Archaeologies.

  • Schats, R. (2015). Malaise and mosquitos: osteoarchaeological evidence for malaria in the medieval Netherlands. Analecta Praehistoricaleidensia, 45, 133–140.
  • Eisen, R. J., Dennis, D. T., & Gage, K. L. (2015). The Role of Early-Phase Transmission in the Spread of Yersinia pestis. Journal of Medical Entomology, tjv128–10.

Spring Reading

It has been a busy spring. I haven’t had a chance to blog as much as I would have liked to, but I have done quite a bit of reading. Some of my reading has been on the complex world of the first plague pandemic. To say that it was transformative would be an understatement.  One of the social questions for the first plague pandemic is how does plague and other natural disasters effect a population that is the midst of conversion?  When the Black Death came it encountered a fully Christian and Muslim world, but not so during the first pandemic. Most of Europe was not yet Christian in 541. There were some Jews, Christians of several varieties, Roman pagans, Germanic pagans, Celtic pagans, Zoroastrians, North African and Middle Eastern pagans, etc. Yet at the end of the pandemic period, Islam is born (and fast growing) and Christianity is dominant in Europe (and united by Rome). The plague began in a polytheistic world and ended in a monotheistic one. What role did the plague play, if any? Yet to be determined. This really isn’t a peripheral issue. Every writer of the first pandemic was involved in this transformation (winners and losers) in some way and it effected how they wrote about the plague and other calamities. So I have a lot of reading to do; below is a start and a few other things that caught my attention.


Marilyn Dunn. (2010) The Christianization of the Anglo-Saxons, c. 497- c.700: Discourses of Life, Death and Afterlife.

Marilyn Dunn (2013) Belief and Religion in Barbarian Europe, c. 350-700. Bloomsbury.

Peter Brown (2015) The Ransom of the Soul: Afterlife and Wealth in Early Christianity. Harvard University Press.

Peter Heather (2013) The Restoration of Rome: Barbarian Popes and Imperial Pretenders. Oxford University Press.


Balbir Singh and Cyrus Saneshvar (2013) Human Infections and Detection of Plasmodium knowlesi. Clinical Microbiology Reviews. 26 (2): 165-184.

Runfola, J. K., House, J., Miller, L., Coltron, L., Hite, D., Hawley, A., et al. (2015). Outbreak of Human Pneumonic Plague with Dog-to-Human and Possible Human-to-Human Transmission — Colorado, June–July 2014. MMWR. Morbidity and Mortality Weekly Report, 64(16), 429–434.

Smith-Guzmán, N. E. (2015). Cribra orbitalia in the ancient Nile Valley and its connection to malaria. International Journal of Paleopathology, 10, 1–12. doi:10.1016/j.ijpp.2015.03.001

Benovitz, N. (2014). The Justinianic plague: evidence from the dated Greek epitaphs of Byzantine Palestine and Arabia. Journal of Roman Archaeology. doi:10.1016/S1473-3099(13)70323-2)

Bernard Bachrach, (2007) Plague, Population, and Economy in Merovingian Gaul. Journal of the Australian Early Medieval Association. 3: 29-57.

Sarris, P. (2002). The Justinianic plague: origins and effects. Continuity and Change, 17(02), 169–182. doi:10.1017/S0268416002004137

Newfield, T. P. (2015). Human–Bovine Plagues in the Early Middle Ages. Journal of Interdisciplinary History, 46(1), 1–38. doi:10.1179/146141010X12640787648612

Inskip, S. A., Taylor, G. M., Zakrzewski, S. R., Mays, S. A., Pike, A. W. G., Llewellyn, G., et al. (2015). Osteological, Biomolecular and Geochemical Examination of an Early Anglo-Saxon Case of Lepromatous Leprosy. PLoS ONE, 10(5), e0124282. doi:10.1371/journal.pone.0124282.s001

Shanks, G. D., & White, N. J. (2013). The activation of vivax malaria hypnozoites by infectious diseases. The Lancet Infectious Diseases, 13(10), 900–906. doi:10.1016/S1473-3099(13)70095-1

Dick, H. C., Pringle, J. K., Sloane, B., Carver, J., Haffenden, A., Stephen Porter, H. A., et al. (2015). Detection and characterisation of Black Death burials by multi-proxy geophysical methods. Journal of Archaeological Science, 1–50. doi:10.1016/j.jas.2015.04.010

Lowell, J. L., Antolin, M. F., Andersen, G. L., Hu, P., Stokowski, R. P., & Gage, K. L. (2015). Single-Nucleotide Polymorphisms Reveal Spatial Diversity Among Clones of Yersinia pestis During Plague Outbreaks in Colorado and the Western United States. Vector Borne and Zoonotic Diseases (Larchmont, N.Y.), 15(5), 291–302. doi:10.1089/vbz.2014.1714

Neil, B. (2013). The Papacy in the Age of Gregory the Great. A Companion to Gregory the Great, 3–28.

Brogiolo, G. P. (2015). Flooding in Northern Italy during the Early Middle Ages: resilience and adaption. Post-Classical Archaeologies, 5, 47–68.

Kostick, C., & Ludlow, F. (2015). The dating of volcanic events and their impact upon European society, 400-800 CE. Post-Classical Archaeologies.  5, 7–30.

Riehm, J. M., Projahn, M., Vogler, A. J., Rajerison, M., Andersen, G., Hall, C. M., et al. (2015). Diverse Genotypes of Yersinia pestis Caused Plague in Madagascar in 2007. PLoS Neglected Tropical Diseases, 9(6), e0003844. doi:10.1371/journal.pntd.0003844.s002

Makundi, R. H., Massawe, A. W., Borremans, B., Laudisoit, A., & Katakweba, A. (2015). We are connected: flea–host association networks in the plague outbreak focus in the Rift Valley, northern Tanzania. Wildlife Research, 42(2), 196. doi:10.1071/WR14254

Plasmodium knowlesi: A New Ancient Malaria Parasite

There are over a hundred different species of the malaria-causing Plasmodium parasites in reptiles, birds and mammals. Being so widespread among terrestrial vertebrates, zoonotic transfer of Plasmodium has come at humans from multiple different sources. Plasmodium knowlesi had been known for some time as a parasite of long-tailed macaques but was not considered a significant human parasite until 2004 when a large number of human infections were identified in Borneo. Molecular analysis implies that Plasmodium knowlesi is as old as Plasmodium vivax and Plasmodium falciparum.

Cover image the phases of Plasmodium knowlesi from the April 2013 issue of Clinical Microbiology Reviews.

Diagnosis is complicated by the histological similarity between Plasmodium knowlesi and Plasmodium malariae. They can’t be distinguished in blood smears like those shown here, so infections were most often misdiagnosed as P. malariae even though they cause a quotidian (daily) fever. The WHO recommends that microscopic detection in areas where P. knowlesi is found report positive results as “P. malariae/P. knowlesi”.  It can only be securely diagnosed by molecular methods  that can distinguish all five human malarial species. PCR based detection methods have shown promise but no one method has been clinically tested with a large enough number of cases to become the standard of care. Antibody-based Rapid Diagnostic Tests (RDT dipstick tests) for malaria do not reliably detect knowlesi malaria which was discovered in humans after the RDT tests were developed. For now in resource poor areas, microscopic analysis followed by molecular testing where available is the only way to detect knowlesi malaria. Clinical research continues for a RDT test that can be employed areas with poor laboratory resources.

Infections have now been confirmed in all of the countries of southeast Asia. Between 2000 and 2011, 881 cases of local P. knowlesi local transmission have been identified in Borneo, with only 8 cases of P. malariae.  It is now suspected that past diagnoses of P. malariae in the region were actually P. knowlesi. Unlike other forms of malaria, P. knowlesi infects more adults than children, although actual infection rates are still not known.

Long-tailed and pig-tailed macaques are the reservoirs for P. knowlesi. In some areas of Malaysia the macaques are around 90% seropositive for malaria, in one study 87% were P. knowlesi. The malaria vector for P. knowlesi and other malarial parasites is Anopheles leucosphyrus group which is also concentrated in southeastern Asia.  Anopheles balabacensis is the most efficient vector, capable of transmitting P. knowlesi from monkey-to-human, human-to-human and human-to-monkey. A. latens, on the other hand, has been most commonly indicated as the vector to humans in Borneo, where it feeds in the high elevation canopy.  As the map below shows, the macacque reservoir and the mosquito vectors are limited to  the islands and peninsulas south-east Asia. It has been hypothesized, based on genetic diversity, that P. knowlesi has caused human malaria as long as  humans, macaques and the Anopheles vectors have all been on the islands of south-east Asia.

Source: Singh, B., & Daneshvar, C. (2013). Human Infections and Detection of Plasmodium knowlesi. Clinical Microbiology Reviews, 26(2), 165–184. doi:10.1128/CMR.00079-12

Difficulty in diagnosis has made it made it challenging to study the full spectrum of knowlesi malaria across the population. What studies have been done show that it produces a full spectrum of malarial disease from mild to fatal. Most cases reported to-date are in adult males, making an occupational exposure a significant possibility.

Symptoms are representative of other malarial infections: fever, chills and rigor, headache, along with a cough, abdominal pain and diarrhea. Gastrointestinal symptoms correlate with high levels of the parasite in the blood. Thrombocytopenia (low platelet counts) is the most common clinical finding and more severe than in either vivax or falciparum malaria, while anemia appears to be mild in knowlesi malaria. In the few pediatric cases that have been observed, they all responded to anti-malarial therapy. In the few cases of severe disease reported, abdominal symptoms have been so severe in some that malaria was not initially suspected. Acute Respiratory Distress Syndrome (ARDS) has been reported in about 50% of severe cases and acute renal failure in approximately 40%. There have not yet been enough confirmed cases of knowlesi malaria to accurately determine the case fatality rate. Although it appears to respond to a wide range of anti-malarial drugs, an optimized treatment based on a sufficient number of cases was not yet available in 2013.

The discovery of Plasmodium knowlesi in humans comes in the context of increasingly successful control of vivax and falciparum malaria in southeastern Asia. Some of the latest epidemiology from Malaysia suggest that 50-60% of the cases of malaria are now knowlesi. There are fears that knowlesi will jeopardize regional malaria elimination efforts. Is the rate really increasing or is it only apparent as levels of falciparum and vivax decrease? Does a real increase represent an opening niche for knowlesi as vivax and falciparum decrease? Only time and more data will answer our questions.

Primary Reference:

Singh, B., & Daneshvar, C. (2013). Human Infections and Detection of Plasmodium knowlesi. Clinical Microbiology Reviews, 26(2), 165–184. doi:10.1128/CMR.00079-12

For additional epidemiology from Malaysia:

Yusof, R., Lau, Y. L., Mahmud, R., Fong, M. Y., Jelip, J., Ngian, H. U., et al. (2014). High proportion of knowlesi malaria in recent malaria cases in Malaysia, Malaria Journal 13(1), 1–9. doi:10.1186/1475-2875-13-168

William, T., Jelip, J., Menon, J., Anderios, F., Mohammad, R., Mohammad, T. A. A., et al. (2014). Changing epidemiology of malaria in Sabah, Malaysia: increasing incidence of Plasmodium knowlesi, Malaria Journal 13(1), 1–11. doi:10.1186/1475-2875-13-390