Haemorrhagic Fever In search of the “culprit” CASE STUDY Study case presentedbyDaniele de Meneghi: UNITO_FMV, Italy; Carla Rosenfeld: UACH, Chile; LudovinaPadre: UEVORA, Portugal; Carolina Pujol: UABC, Mexico, SAPUVETNET IIImembers of group VII.
There was an outbreak of hemorrhagic leptospirosis, in a Balkan country, a year ago. The epidemiological study identified infected cattle as the probable source. This outbreak in animals was related to the floods that were caused by the heavy seasonal rains. As a precautionary measure all cattle in the area were vaccinated. ANTECEDENTES
Therefore, the hospital has requested the collaboration of a veterinarian (you) in assessing the situation. A child with hemorrhagic syndrome has infected other people and the doctors suspect a zoonotic disease but have ruled out leptospirosis, whereby they have requested your help in investigating the cause. ANTECEDENTES
A child called Pedro presented the following symptoms • on May 2: chills, myalgia, cough, nausea, anorexia, • vomiting, headache and backache. • On May 28 he was taken to the General Practitioner at the local health centre, where he was treated with antibiotics, antipyretics and corticosteroids. • On May 29, as he had not improved, Pedro was taken to a private paediatrician. He was prescribed a wide range of antibiotics and it was recommended that he should be hospitalized if he does not respond to the treatment. • On May 31, he was hospitalized in the university paediatric clinic of the capital. • At this time the child continues to present the same initial symptoms in addition to pain in the legs. Five days later there is massive haemorrhage, hematemesis, melena and petechiae. Antecedentes
The most serious symptoms included : petechiae, epistaxis and haemorrhage.
FAÇA UMA ANAMNESIS including: • Individual/time/place • Environemental factors Discuss and answer (1)
The child lives in a cattle breeding agricultural region in a Balkan country. More background (1)
More background(1) The area has an altitude of 500 to 1500 m above sea level with warm climate, fragmented settlements and alternating forest and cultivated lands. The area is mainly used for family farm production (80%), with approximately 2500 inhabitants in the municipality. The municipality has 2,500 inhabitants, 80% of which are engaged in agriculture.
According to the information, which laboratory tests would you request? Discuss and answer (2) QUETIONS
Blood analysis has indicated changes in coagulation parameters, among others. • Toxicological results are negative . Discuss and answer (2)
5 days before a tick had been removed from the child’s head. More background (2)
More background (2) Two days later the grandfather became sick with similar symptoms. In a neighbouring area of the same municipality five farmers have shown symptoms similar to those of Pedro.
A week later, the nurse that was attending the child presented similar symptoms. • Neither the farmers nor the breeders have reported diseases in animals.
Discuss and answer (3) Which diseases could be considered for differential diagnosis (Dx)? Is it important to determine if there is a history of any of them in the area? Which tests are to be carried out and for which infectious agents?
Diseases that cause haemorrhagic syndrome / Dx. differential Lassa fever Marburg Ebola fever Yellow fever Hantavirus infections Rift Valley fever Omsk haemorrhagic disease Kyasanur jungle disease Crimea-Congo Haemorrhagic fever (CCHF) Haemorrhagic Dengue
Otherdiseases: Leptospirosis Shigellosis Recurrent fever
Serological test results: negative Requested tests: Serological Molecular
Discuss and answer (3) Are the negative results of the serological test conclusive?
Results of molecular tests: PCR tests of blood obtained during paracentesis are positive for Crimean-Congo haemorrhagic Fever (CCHF).
Discuss and answer (4) • What kind of common information should be looked for between Pedro and the other individuals who have been affected? • Usual means of infection • Relation with the cattle • Increase in the Hyalomma sp. population • Possible direct infection through contact with infected blood.
Discuss and answer (5) -How should the epidemiologic situation be studied / presented? -Make an epidemiologic questionnaire.
No. of cases = • No. of deaths= • Lethality rate = • Population at risk = • Mortality rate= • Rate of attack =
No. of cases = 7 • No. of deaths= 1 • Lethalityrate= 1/7 16% • Population at risk= 2 000 (farmers) • Mortalityrate= 0.05% (1/100,000) • Rate of attack= 7/2000 = 0.35% or3 in 1000
Discuss and answer (6) • - What was the most probable source of infection? • - What studies would you carry out on the animals and the vector population? • What would be the control and preventive measures for this disease? • - Should the infected cattle be slaughtered? • - Do you think this outbreak is related to environmental and climatic changes?
Case studypreparedbymembers of SAPUVETNET III project GroupVIIDaniele de Meneghi: UNITO_FMV, ItalyCarla Rosenfeld: UACH, ChileLudovina Padre: UEVORA, Portugal Carolina Pujol: UABC, Mexico