Investigation of infectious laryngotracheitis outbreaks in Namibia in 2018

  • Umberto Molini
  • Gottlieb Aikukutu
  • Siegfried Khaiseb
  • Barbara Kahler
  • Jolandie Van der Westhuizen
  • Giovanni Cattoli
  • William G. DundonEmail author
Short Communications


Between July and August 2018, two outbreaks of infectious laryngotracheitis caused the death of over 116,000 commercial poultry (layers and broilers) near the city of Windhoek, Namibia. A third outbreak occurred in September 2018 in the north of the country approximately 800 km from the original outbreaks. Sample collection and molecular epidemiological analyses revealed that the outbreaks were most likely caused by poor vaccination practices leading to the reversion to virulence of an ILT vaccine strain. The analyses also indicate that inaccurate declarations were made by one of the farms involved and that illegal movement of animals most likely occurred.


Poultry Infectious laryngotracheitis Gallid alphaherpesvirus-1 Namibia Phylogenetic analysis ICP4 Vaccination 



The sequences from this study were generated through the Sequencing Services of the Animal Production and Health Sub-programme of the Joint FAO/IAEA Division in Vienna, Austria.

Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interests.

Ethical approval

This article does not contain studies on live animals.


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© Springer Nature B.V. 2019

Authors and Affiliations

  1. 1.Department of Pathobiology, School of Veterinary Medicine, Faculty of Agriculture and Natural ResourcesUniversity of NamibiaWindhoekNamibia
  2. 2.Central Veterinary Laboratory (CVL)WindhoekNamibia
  3. 3.Department of Nuclear Sciences and ApplicationsAnimal Production and Health Laboratory, Joint FAO/IAEA Division of Nuclear Techniques in Food and Agriculture, International Atomic Energy Agency LaboratoriesSeibersdorfAustria

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