Plague: expert says, ‘The pulmonary form has a 100 per cent mortality rate, which falls to 50 per cent with “old” antibiotics’

The latest figures were released by the World Health Organisation as recently as 29 September: the report covering the period from 2019 to 2025 across 10 countries records 3,847 suspected cases and 423 deaths, corresponding to a mortality rate of 11 per cent. Most cases were in the Democratic Republic of the Congo and Madagascar, where the plague remains endemic in certain areas. However, “the plague can also occur in countries that do not report cases, and the annual number of cases varies depending on the timing, location and scale of outbreaks”, the WHO emphasises, a point that fits perfectly with the case of the 28-year-old researcher who died in Siberia at Shelekhov Hospital, following an incident possibly involving the opening of an infected vial. ‘In 2018 alone, I am aware of 248 cases, 98 per cent of which were in Madagascar and the DRC’, explains Antonio Cascio, Professor of Infectious Diseases at the University of Palermo, Director of Infectious Diseases and the Regional AIDS Reference Centre at the Giaccone Polyclinic in Palermo, and a member of the Italian Society of Infectious Diseases (SIMIT). He outlines the causes, risks and possible treatments for the disease, which, in the Italian collective imagination, is forever etched by Alessandro Manzoni’s description of it in *The Betrothed*.

How is the disease transmitted?
‘The plague is generally transmitted by the bite of an infected flea, the rat flea known as Xenopsylla cheopis, but it can also be contracted through direct contact with infected animals or people, or via the air.’ Listed in descending order of likelihood of transmission, it is then spread through direct contact with infected animals or people, for example through scratches or handling of carcasses; through inhalation of droplets – that is, infected droplets transmitted by a sick animal or person; finally, and this is the rarest case, by eating contaminated raw meat. The clinical forms can vary: in the most common form, which is the bubonic plague described by Manzoni, large swollen lymph nodes form in the neck and armpits, accompanied by a high fever and headache, and the condition can progress to septicaemia if left untreated. Then there is a form that manifests as septicaemia, a haemorrhagic form that causes gangrene in the extremities and is therefore known as the ‘Black Death’. Finally, there is pneumonic plague.

This is the case with the Siberian researcher...
We are talking here about a fulminant form of pneumonia characterised by a cough and bloody sputum. It has a 100 per cent mortality rate and the mortality rate exceeds 50 per cent even when treated with the correct antibiotics. It is fulminant because the incubation period ranges from a few hours to six days, depending on the bacteria inhaled, and death occurs within 24–48 hours.

He mentioned treatments: what options do we have? 
Do the classic, ‘old’ and inexpensive antibiotics such as gentamicin, ciproxin or tetracyclines work? so there is no problem with the availability of medicines, but if you are far from a medical centre – as is often the case in developing countries – time is lost and the disease progresses. In the case of the scientist who died in Siberia, I imagine she took antibiotics straight away upon infection, but the pulmonary form is the most lethal. As for ‘bubonic’ plague, the estimated mortality rate stands at 15–17 per cent, but in the pre-antibiotic era, 75 per cent of cases were fatal.

Are there any useful tests?
There are accurate and reliable diagnostic tests such as PCR, but it is difficult to carry them out in settings such as the Savannah. In practice, therefore, the diagnosis is clinical: if a bubo appears, or in the event of gangrene of the nose or fingers, there is no time to wait for a diagnosis.