Tropical Medical Entomology in Civil-Military Collaboration
with the Bernhard Nocht Institute for Tropical Medicine

Albert Eisenbarth^a

^a Department of Microbiology and Hospital Hygiene, Bundeswehr Hospital Hamburg

Summary

Tropical medical entomology encompasses both fundamental and applied research aimed at improving the health of impacted populations. Recognising the importance of these issues in a military context, the Bundeswehr Hospital Hamburg has partnered with Germany’s largest institute for tropical medicine, the Bernhard Nocht Institute, for two decades, benefiting both civilian and military sectors.

Keywords: Entomology; Vector; Surveillance; Repellent

Introduction and Background

Entomology, the study of insects and arthropods, is a classical discipline of biology with diverse applications. Since the inception of tropical medicine in the 19th century, it has been a cornerstone of the entire field. Medical entomology has continuously evolved and remains central to the research and prevention of vector-borne diseases. It played a crucial role at the onset of the Bundeswehr’s tropical medical engagement in Hamburg 20 years ago, such as safeguarding soldiers’ health during the Afghanistan deployment by minimising the risk of leishmaniasis [3] and later stabilisation missions in the Sahel, primarily for malaria prevention [4].

In addition to preparing entomological reports for thediagnostics departmentof civilian partners, current focus areas include research collaborations with the Bernhard Nocht Institute for Tropical Medicine (BNITM) and civilian international partners in sub-Saharan Africa and Latin America. A military medical collaboration with the Royal Thai Armed Forces is also being developed. The Bundeswehr Hospital Hamburg benefits from enhanced networking and knowledge exchange with national and international experts, and access to reference materials from tropical and subtropical countries – such as vectors and their pathogens – which are invaluable for surveillance measures in these regions or detecting invasive species in Europe.

The following provides an overview of current research areas related to entomology.

Baseline Transmission and New Intervention ­Practices for Loiasis in Central Africa

A geographic research focus is Gabon, evident from the number of activities there. The primary focus is on studying a parasitic worm disease transmitted by horseflies in its main distribution area in the equatorial rainforest: African eye worm´s disease, also known as loiasis. The BNITM’s Institute of Clinical Research has maintained a research station in collaboration with the Centre de Recherches Médicales de Lambaréné (CERMEL) in an endemic hotspot (Figures 1–2). This station is well-suited for entomological work and is utilised accordingly. Since 2021, the Bundeswehr Hospital Hamburg has supported the establishment, operation, and evaluation of long-term vector surveillance to determine natural loiasis transmission. Continuous data on biting density, infection rates, and transmission potentials of vector species provide valuable insights into the natural transmission dynamics, which remain poorly understood. Additional interesting aspects involve studies on the effectiveness of commercial repellents against the diurnal and relatively large horseflies of the genus Chrysops. The skin repellents showed mixed results, with some failing and others providing only limited protection [1]. New study results comparing skin and clothing repellents separately and in combination are forthcoming and currently being evaluated.

Fig. 1: Research Station Institute de Recherches en Santé de Sindara (ISSA) Exterior View. More information at http://loaloa.org. (Image rights: E. Mehmel)

Fig. 2: Microbiology Laboratory of the ISSA Research Station in Sindara. (Image rights: A. Eisenbarth)

A project aimed at optimising trap development is still in its early stages. Better traps are necessary because market-available models achieve very low catch rates for loiasis vectors. Similar to tsetse flies, the main vectors of loiasis reproduce relatively slowly, so more efficient horsefly traps could significantly reduce the transmission risk for populations in endemic areas. Naturally, such traps would also be highly useful in other climate zones – such as North America, Scandinavia or the Baltics – where Chrysops horsefly traps could potentially reduce significant local nuisances.

Malaria Detection Tool for Mobile Use in Vectors

A military medical research project aimed to enhance the force health protection of deployed personnel in malaria-endemic areas (notably in Mali and Niger) by developing improved pathogen surveillance in vectors. A point-of-care test system for malaria pathogens based on human samples was adapted for use with locally captured malaria mosquitoes. The development and testing phase was successful, both with material from the BNITM’s mosquito breeding and wild captures from Gabon and Colombia. The results were recently published in a scientific journal [2].

Although the system’s general deployability has been proven after successful testing, it is still unknown whether zoonotic malaria pathogens – i.e., species originating from animal reservoirs that can also infect humans – can be reliably detected. In some regions of Southeast Asia, so-called “monkey malaria” is relatively common, prompting the Bundeswehr Hospital Hamburg to collaborate with the Armed Forces Research Institute for Medical Sciences (AFRIMS) of the Royal Thai Armed Forces to empirically answer this question through on-site testing in endemic zones in Thailand.

Ectoparasite and Pathogen Screening of „Bush Meat,“ Domestic Animals, and Humans in the Tropics

Another area of activity in the tropical medical entomology of the Bundeswehr Hospital Hamburg involves ectoparasites from the tropics, including bedbugs, mites, fleas, lice, and especially ticks. Extensive sample material, particularly from hard ticks, was collected from various host animals (wild and domesticated) and from humans, identified, and examined for transmissible pathogens. Little is known about many tick species found, especially those from sub-Saharan Africa. This is even more true for partially undescribed pathogen species detected via molecular methods. The results are being compiled in several independent publications and will be published soon.

Characterisation of Blood-Sucking Vectors from Sample Collections in Tropical and Subtropical Partner Countries

In addition to the above-described research projects, various vector group samples were collected for biodiversity studies and the epidemiology of vector-borne diseases. The spectrum is broad, including mosquitoes, sandflies, blackflies, biting midges, tsetse flies, horseflies, and the aforementioned ectoparasites from Gabon, Nigeria, the Democratic Republic of the Congo, Cameroon, Mauritania, Colombia, and the Italian Mediterranean island of Sardinia. Such data complement our understanding of the regional occurrence of different vector groups in an ever-changing environment.

Conclusion

(Tropical) medical entomology makes a significant contribution to force health protection. The close cooperation of the Bundeswehr Hospital Hamburg with both the BNITM and partners in tropical and subtropical countries leads to the development of capabilities and expertise that are essential not only for deployments in the tropics. Particularly in light of climate change and the sometimes alarming changes in insect and arthropod populations in Europe, these medical capabilities are also crucial for national and alliance defence.

References

1. Doumba Ndalembouly AG, Boussougou-Sambe ST, Ngossanga B, et al. Protective efficacy of skin-applied arthropod repellents against Chrysops bites in a Loa loa hyperendemic region in Gabon: A placebo-controlled randomized clinical trial of DEET, icaridin, citriodiol, and IR3535. Travel Med Infect Dis. 2025 Sep-Oct;67:102899. read more
2. Eisenbarth A, Adegnika AA, Boussougou-Sambe ST, et al. Assessment of automated loop-mediated isothermal amplification-(LAMP-)based xenomonitoring for Plasmodium spp. in Anopheles mosquitoes. Malaria J. 2026 Apr 28;25(1):183. read more
3. Krüger A, Strüven L, Post RJ, Faulde M. The sandflies (Diptera: Psychodidae, Phlebotominae) in military camps in northern Afghanistan (2007-2009), as identified by morphology and DNA 'barcoding'. Ann Trop Med Parasitol. 2011 Mar;105(2):163-176. read more
4. Maaßen W, Frey C, Frickmann H, Erkens K. [Specialists in tropical medicine of the German Armed Forces: operational experience in Mali].Flugmedizin Tropenmedizin Reisemedizin – FTR. 2017;24(02): 81–88. (Article in German language) read more

Manuscript Data

Citation

Eisenbarth A. Tropical Medical Entomology in Civil-Military Collaboration with the Bernhard Nocht Institute for Tropical Medicine. WMM 2026;70(9E):5.

DOI: https://doi.org/10.48701/opus4-964

Author

Senior Government Councilor Dr. rer. nat. Albert Eisenbarth

Department of Microbiology and Hospital Hygiene

Division Tropical Medical Microbiology and Entomology

Bundeswehr Hospital Hamburg

Branch at Bernhard Nocht Institute for Tropical Medicine

Bernhard-Nocht-Str. 74, D-20359 Hamburg

E-Mail: alberteisenbarth@bundeswehr.org