Q fever serologic surveillance program for sheep and goats at a research animal facility

Since Q fever is a potential risk to personnel working with small ruminants, the serologic status of sheep and goats received at a medical school animal facility for research was evaluated. A total of 104 sheep and 102 goats were subjected to blood sample-collection procedures on arrival, as well as after a 2-week quarantine period, and the sera were tested for Q fever specific antibodies by complement-fixation (CF) and microagglutination (MA) tests. The results from the 2 tests were compared and analyzed for seroconversion. On the basis of the CF test, 14 sheep and 3 goats were considered positive; these included 7 sheep and 2 goats that seroconverted during the quarantine period. In contrast, 1 sheep and 5 goats were found positive by the MA test, which also detected seroconversion of 1 sheep and 1 goat. The use of both tests for serologic surveillance of Q fever in sheep and goats increased the likelihood of detection. Management safety practices are also required to minimize the risk of disease transmission.     

A serologic study on Toxoplasma gondii infection in slaughtered sheep and goats in Qazvin Province,Iran

Background

Toxoplasma gondii is a common protozoan parasite among all mammals, in particular small ruminants, worldwide. Traditional husbandry can be a major risk factor for infection of sheep and goats with this parasite.

Objectives

The present study aimed to determine the current status of the prevalence for T. gondii in livestock of Qazvin Province.

Methods

In this cross-sectional study, the sera of 455 sheep and 375 goats were examined to detect anti-Toxoplasma IgG antibodies by using in-house indirect ELISA.

Results

Overall, 33.62% (153/455) of sheep and 36.41% (130/375) of goats were positive for anti-Toxoplasma IgG antibodies with no statistically significant difference. The prevalence rate of T. gondii among the sheep of Qazvin County was significantly higher than in Abyek and Abhar counties (p < 0.001).

Conclusions

The results of the present study indicate that the prevalence of T. gondii in sheep and goats of the study area is high. Therefore, the meat of the animals reared in this area can be a potential source of human infections by this parasite.

     

The seroprevalence of coxiellosis (Q fever) in Ontario sheep flocks.

A serological survey for Coxiella burnetii was undertaken on a randomly selected population of 103 Ontario sheep flocks. Twenty-two flocks had at least one positive ewe; seven flocks had two or more reactors. The positive flocks were geographically clustered northwest of Guelph. Crutch-clipping of the ewe's wool prior to lambing, and total confinement housing at lambing in winter and spring seemed to lower the probability of seroreactivity of the flock (p less than 0.05). The study suggests that sheep are not a major reservoir for Coxiella burnetii in Ontario.     

Q fever vaccination of sheep: challenge of immunity in ewes

Adult ewes (17 months of age) were vaccinated against Coxiella burnetii, using a formalin-inactivated whole cell (WC) phase I Henzerling strain vaccine or a chloroform methanol residue (CMR) vaccine. Nineteen pregnant ewes were placed in 3 categories [(i) unvaccinated, (ii) WC vaccine, and (iii) CMR vaccine] and were challenge exposed at approximately the 100th day of gestation with 210,000 plaque-forming units of C burnetii inoculated subcutaneously. Shedding of rickettsiae was measurably reduced, but was not prevented in vaccinated groups, as shown by inoculating ewes' placental tissues, amniotic fluid, and colostrum into mice, as well as by histopathologic lesions of placental tissues. The rickettsiae were shed in the placenta, amniotic fluid, or colostrum in 6 nonvaccinated ewes. In comparison, rickettsiae were detected in placental inoculations from 2 of 6 ewes in the WC vaccine group and 1 of 6 in the CMR group. In contrast to those in the vaccinated ewes, placentitis, high concentrations of rickettsiae in microscopic preparations, and weak lambs were typical for the nonvaccinated ewes.     

Seroepidemiological study of Q fever,brucellosis and tularemia in butchers and slaughterhouses workers in Lorestan,western of Iran

Most zoonoses are occupational diseases. Q fever, brucellosis and tularemia are major zoonotic diseases for butchers and slaughterhouse workers. However, little information is available about these infectious diseases in such professional populations in western of Iran. The aim of this study was to investigate the seroprevalence and risk factors associated with these three zoonoses among butchers and slaughterhouse workers in the Lorestan province of Iran. In 2017, 289 individuals (144 butchers or slaughterhouse workers, and 145 people from the general population) were enrolled in 11 different counties of this province. Collected serum samples were tested by ELISA for detection of IgG antibodies against Coxiella burnetii, Brucella spp. or Francisella tularensis antigens. The seroprevalence of Q fever, brucellosis and tularemia among all participants were 23.5%, 31.8% and 3.8%, respectively. The seroprevalence of brucellosis and Q fever among butchers and slaughterhouse workers (43.7% and 29.8%, respectively) were significantly higher (p < 0.05) than those of the general population (20% and 17.2%, respectively). A contact history with small ruminants (sheep and goats) was associated with a higher risk of positive serology for all three studied zoonoses. The high seroprevalence for Q fever and brucellosis we found among butchers and slaughterhouse workers suggests that both diseases are common in these populations of the Lorestan province. Since these two infectious diseases are clinically unspecific, they must be systematically included in the etiological diagnosis of infectious diseases occurring in these at-risk populations. In addition, we recommend specific training programs as well as the use of personal protective equipment in these occupational groups to reduce the occurrence of these zoonotic diseases.     

Seroepidemiological studies on the detection of Q fever in sheep in middle Thuringia]

In a random samples test altogether 4337 sheep of varying ages from several herds of different sizes in the middle region of Thuringia were investigated with complement fixing test for the existence of Q fever. In 47.1 per cent of the tested herds and in 5 from 8 of the included districts Q fever reagents were provable. The serological detection quota of all tested sheep amounts to 1.11 per cent, but the percentage of serological reagents in mother-sheep was 1.36 per cent, in the female young sheep 1.04 per cent and in the lambs 0.74 per cent. The investigations of rams and sheep for slaughter were negative. Serological testing in 7 sheep showed a Q fever antibody persistence about 6 until 10 months. Increased animal concentration and adverse conditions led to an increase of the Q fever seroprevalence in the herds.     

Spread of Coxiella burnetii infection in a flock of sheep after an episode of Q fever

In October 1998, two abortions associated with Coxiella burnetii occurred in a group of 34 pregnant ewes in the sheep flock belonging to INRA Tours-Nouzilly. The flock was kept in groups of approximately 40 ewes, which were housed together in the same accommodation. The prevalence of C burnetii infection in the groups was investigated by using ELISA and PCR tests, which revealed a high prevalence of C burnetii. The ewes were treated with oxytetracycline to reduce the shedding of C burnetii and to prevent further abortions. Nevertheless, five abortions attributed to C burnetii occurred in January and March 1999 in three groups of ewes, and 24 of the ewes still shed the bacteria into their vaginal tracts. In addition, a serological study was carried out during the first year of life of the female lambs born in 1999 and 2000; 12 per cent of 113 lambs born in 1999 were seropositive for C burnetii by ELISA, and half of the ELISA-positive lambs were born either to serologically positive ewes or to dams that excreted the pathogen into their vaginal tracts. However, all the 150 lambs born in 2000 were ELISA-negative, suggesting that the preventive measures undertaken had suppressed both the abortions and the shedding of C burnetii, and reduced the transmission of the agent.     

Seroprevalence of Q fever (coxiellosis) in sheep from the Southern Marmara Region, Turkey

Little information is available in Turkey on Q fever, a zoonose caused by Coxiella burnetii and transmitted from domestic ruminants. This study aimed at investigating the seroprevalence in sheep flocks from three provinces (Bursa, Balikesir and Canakkale). Serosurvey was undertaken on 42 flocks, which were categorised by sizes. Sera were collected randomly from specific age groups within the young population. CHEKIT Q-fever ELISA kit was used to identify the infection in sheep. The results showed that 20% (n=151) of sheep were seropositive. A total of 34 flocks (81%) revealed at least one seropositive animal. Higher seroprevalence was observed in Balikesir region. Larger flocks resulted more infected than medium and small flocks. An association was found between seropositivity and age, when the primiparous ewes (1-year old) had higher antibodies rates than newborn sheep (aged less than 10 months) or biparous ewes (2 years old). These results showed that Q fever infection was common and circulating in the studied region, hence encourage efforts to propose measures that could reduce the spread and the zoonotic risk.     

Q fever in Greece: Findings of a 13 years surveillance study

Q fever is an endemic disease in different parts of Greece. The current study aimed to investigate the prevalence of acute Q fever disease in Greece through the operation of the national reference centre for Q fever.A total of 5397 sera were received from febrile patients under the suspicion of Q fever infection during a 13 years period (2001–20013). A questionnaire was filled in by the clinicians containing certain clinical/epidemiological/demographic information.The diagnosis was based both on IFA (IgG and IgM phase II antibodies against Coxiella burnetii) and on molecular means.A total of 685 (12.7 %) samples were initially tested positive for acute Q fever. The mean (±SD) age of patients was 55.3 years (±18.7). Out of the 489 convalescent samples, 134 (27.4 %) samples indicated a minimum of a four-fold seroconversion and were considered as laboratory confirmed cases of acute Q fever. Pneumonia was the most frequently encountered clinical symptom with presence in 6.8 % of all positive samples. Forty six (46) patients were laboratory confirmed as chronic Q fever cases.Climate seemed to influence the distribution of Q fever cases throughout the years. The findings of the current study comply with past studies carried out elsewhere that had demonstrated a clear relation of the disease with temperature, south winds, etc.This study represents the first large scale attempt to gather a long period information on Q fever infection in Greece. The findings of the current study support the fact that Q fever is an important endemic zoonotic disease in Greece and needs increased awareness by clinical physicians and health care system.