Parrot Trade and the Potential Risk of Psittacosis as a Zoonotic Disease in Indonesian Bird Markets

Simple Summary There are clear links between wildlife trade and emerging infectious diseases including zoonotic diseases. In some cases, this leads to global outbreaks or even pandemics as recently seen with SARS and COVID-19 for instance. One of the first properly documented global pandemics caused by the trade of wildlife at a global level was the Great Parrot Fever Pandemic of 1929/1930. This pandemic was caused by psittacosis, a respiratory disease that can be transmitted to humans from infected birds (once transmitted to humans the disease is known as avian chlamydiosis). We assessed the risk of psittacosis becoming a zoonotic disease in Indonesia's bird markets where a wide range of wild-caught species, including parrots, are traded. In 14 markets on the islands of Java and Bali, we recorded almost 4500 parrots of 21 genera from all parts of the world and these were traded alongside each other. Genera offered for sale together did not cluster into geographic groups, were sold during all months of the year, and for 12/21 genera the presence of psittacosis had been reported in the past. We conclude that the omnipresence of wild-caught parrots from various geographic regions in large numbers within the same bird markets (visited by 100 s of people daily) increases the likelihood that psittacosis is indeed present. This poses a real risk for the zoonotic spread of avian chlamydiosis to humans.Abstract Wildlife trade, both legal and illegal, is increasingly recognized as a key factor in the rise of emerging viral infectious diseases, and this is especially apparent in Asia, where large numbers of wildlife are openly offered for sale in bird markets. We here focus on the risk of Psittacosis becoming a zoonotic disease in the wildlife markets of Java and Bali, Indonesia. Psittacosis is particularly prevalent in parrots (hence the name), and the trade in parrots was instrumental in the Great Parrot Fever Pandemic in 1929/1930. Between 2014 and 2023, we conducted 176 surveys of 14 bird markets, during which we recorded 4446 largely wild-caught parrots for sale. On average, each market had nine genera on offer, and the diversity of genera increased with the increasing presence of parrots (up to 16 genera). For most of the bird markets during each survey, parrots from different genera and originating from different parts of the world, were offered for sale alongside each other. Genera offered for sale together did not cluster into natural (geographic) groups. We found no temporal difference in the sale of parrots. We conclude that the omnipresence of wild-caught parrots from various geographic regions in large numbers within the same bird markets increases the risk that psittacosis is present and that this poses a real risk for the zoonotic spread of avian chlamydiosis to humans.