Q fever and prevalence of Coxiella burnetii in milk

Background Q fever is a zoonosis caused by Coxiella burnetii. In humans, although it has been predominantly considered an occupational hazard, in the last decades, Q fever outbreaks have also been reported in various countries, indicating its importance as an emerging public health threat. Domestic ruminants are considered as the most important sources of human infection. In fact, both symptomatic and asymptomatic infected ruminants shed the bacterium into the environment with birth products, but also in urine, faeces, vaginal mucus and milk. Q fever in humans is mainly asymptomatic, but it also may manifest itself as an acute or chronic disease with long-term sequelae. Inhalation of infectious aerosols usually causes the disease in humans, but the presence of C. burnetii in raw milk raises concern over the role of milk as a source of infection. Scope and approach In this review data on Q fever in humans are summarized and the possible transmission of C. burnetii to humans by consumption of unpasteurized milk is discussed. In addition, an overview of the published data on the prevalence studies of C. burnetii in raw milk in various countries is provided. Key findings and conclusions Recent surveys conducted in many countries have revealed that the prevalence of C. burnetii in raw milk can vary over a wide range from 0% to as high as 95%. Based on recent survey data, the risk of C. burnetii infection by consuming unpasteurized milk and raw milk products cannot be considered negligible. © 2017 Elsevier Lt

Prevalence of methicillin-resistant Staphylococcus aureus in milk and dairy products

Staphylococcus aureus is an opportunistic Gram positive pathogen and the causative agent of many human and animal diseases. It is also an important human foodbome pathogen. Certain strains of S. aureus can produce staphylococcal enterotoxins (SEs) in foods and cause staphylococcal food poisonings (SFP). In recent years S. aureus has been increasingly associated with antibiotic resistance. Methicillin-resistant S. aureus (MRSA) includes those strains that have acquired genes conferring resistance to methicillin and essentially all other beta-lactam antibiotics. MRSA was initially reported as a nosocomial pathogen in human hospitals (or hospital-associated MRSA, HA-MRSA). Since the 1990s, community-acquired or community-associated MRSA (CA-MRSA) infections have also been reported to affect people having no epidemiological connection with hospitals. More recently, MRSA has been isolated from most food-producing animals and foods of animal origin, raising public health concerns. MRSA strains have been isolated from cows' or small ruminants' milk and various dairy products in many countries. The MRSA prevalence in milk and dairy products recorded in different countries or even regions of the same country differs significantly. High MRSA prevalence have been recorded in milk produced in most African countries, for instance as high as 60.3% in Ethiopia. The MRSA prevalence in Asian countries varies from high e.g. 28.3% in Iran to low (e.g. in Korea and Japan). In most European countries, the MRSA prevalence in milk and dairy products has been generally found to be low. In the US and Canada, zero to low MRSA prevalence estimates have been reported. The investigation of MRSA prevalence in milk may serve as a tool for assessing both the sanitary conditions employed in dairy herds and the health risks that humans may encounter when infected with antibiotic-resistant strains

Q fever and seroprevalence of Coxiella burnetii in domestic ruminants

Q fever is a zoonosis caused by Coxiella burnetii, an obligate intracellular gram‑negative bacterium. Infection by C. burnetii has been demonstrated in many animal species, but ruminants are the major reservoirs and the main sources of human infection. In ruminants, C. burnetii infection is often asymptomatic, but it has been also associated with infertility and abortions. In humans, Q fever was considered predominately an occupational hazard due to close contact with infected ruminants by means of their contaminated birth products, urine, feces or milk. Q fever has recently gained renewed attention after the large outbreak in the Netherlands in 2007‑2009, indicating its importance as an emerging public health threat. The seroprevalence of C. burnetii in ruminants is commonly detected by various tests but no official standard technique is still available. According to surveys conducted in many countries of the five continents, a relatively high proportion of farm ruminants are found seropositive to C. burnetii. The only country with an apparent zero prevalence is New Zealand. The seroprevalence in goats and sheep is usually higher than cattle

Vibrio parahaemolyticus in seafood - associated outbreaks

Among the 30 species of the genus Vibrio, only 13 of them are pathogenic to humans. All pathogenic vibrios have been reported to cause foodborne diseases, although V. parahaemolyticus is considered the most important pathogenic Vibrio. V. parahaemolyticus is a halophilic bacterium that occurs naturally in aquatic environments worldwide. The pathogen caused sporadic diarrhoea mainly associated with the consumption of raw or undercooked seafood up to recent years. Since 1996, the incidence of V. parahaemolyticus infections has increased dramatically. V. parahaemolyticus is the leading cause of seafood-associated bacterial gastroenteritis in the United States and of the half foodborne outbreaks in some Asian countries. This increase in incidence has been related to the emergence of the O3:K6 serovar. The pathogenic V. parahaemolyticus strains can produce a thermostable direct hemolysin or a thermostable direct hemolysin-related hemolysin, which are encoded by the tdh and trh genes, respectively. Vibrio parahaemolyticus has not been included in the microbiological criteria of E.U. Food legislation, probably because the risk by this pathogen was considered rather low in Europe. However, climate changes favour the growth of the pathogen in seawater. Recent studies in Spain and France have shown that V. parahaemolyticus infections from seafood consumption have been increased. The emergence of the pathogen in Europe is of public health concern and emphasizes the importance of microbiological surveillance and control programs for V. parahaemolyticus