Prevalence of Coxiella burnetii in Human, Animal Hosts and Hard Ticks in West Mazandaran Province Iran, 2003-4

Query (Q) fever is caused by hard ticks infected by Coxiella burnetii. It belongs to a group of diseases, classified as zoonosis, that are common between human-beings and animals. This study was conducted with the objective of defining the prevalence of Coxiella burnetii in humans, animal hosts and hard ticks in the western part of the Mazandaran province.

Blood samples were collected from subjects randomly selected from individuals working in professions that brought them in close contact with animals. We also obtained blood samples from randomly selected farm animals, and a limited number of samples from stray dogs in the community. Hard ticks were collected from the bodies of farm animals and also from the shrubs around the farms. The ticks were identified by genus, species and developmental stage. All blood samples were tested by PCR. With the aid of two pairs of primers especially designed 16S rRNA for Coxiella burnetii, PCR and then Nested–PCR was done on each sample.

A total of 2417 hard ticks were removed from: animal bodies (1644) and from the shrubbery (773). The hard tick species were identified as follow: • Ixodes ricinus (72%) • Hyalomma anatolicum anatolicum (15%) • Boophilus annulatus (9%) • Haemaphysalis sulcata (3%) • Dermacentor marginatus (1%) No positive case of Coxiella burnetii was observed in 1052 investigated samples in this study (120 humans, 135 sheeps, 102 cows, 60 goats, 20 dogs, 10 hedgehogs and 605 hard ticks).

This study did not find any evidence of contamination with Coxiella burnetii in the samples collected from the rural areas of Western Mazandaran. To define the prevalence of this microorganism in different parts of northern Iran further epidemiological studies are necessary.